Geotechnical Report

File No.494-64 March 24, 2007

Page 2 10,000 Santa Monica Blvd.

EXECUTIVE SUMMARY An evaluation of the proposed construction of a multi-story condominium building over several levels of subterranean parking was performed by this office. The evaluation consisted of historical aerial photographic research, review of geotechnical reports for surrounding buildings, an extensive subsurface investigation including laboratory testing, geologic analysis of seismic hazards, and soil engineering analysis of potential settlement and liquefaction effects on the proposed building. Based on our findings the site is free from hazards associated with landsliding, slippage, soil erosion, subsidence, and liquefaction. The Design Basis Earthquake and estimated peak ground acceleration for the site are average and will not necessitate unusual structural design. Affects from typical settlement or seismic hazards can be mitigated with standard foundation design. There are no known active faults located close to the property. Heavy seepage was encountered at depths between 35 and 50 feet (227’ to 216’ elevation) below the ground surface and is likely representative of groundwater. The shallowest seepage (closest to the ground surface) was encountered along the south side of the site. If the below grade portion of the building is proposed deeper than the current groundwater level then permanent dewatering of the site or a special foundation and slab design will be required. Based on the geometry of the surrounding building foundations and the depth of the groundwater there will be no detrimental affect to adjacent structures during permanent or temporary dewatering (if it is needed). Although dependant upon the final building design, preliminary analysis indicates that the new condominium building will be founded on a conventional mat foundation.

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1.0 1.1


INTRODUCTION PURPOSE

The purpose of this investigation was to evaluate the existing geotechnical conditions at the subject site and to provide design and construction criteria for the construction of a multi-story condominium tower of approximately forty stories in height with approximately four subterranean levels of parking. 1.2

SCOPE OF SERVICES

The scope of work performed during this investigation involved the following; •

Research and review of available pertinent geotechnical literature;

• Subsurface exploration consisting of the excavation of four borings (B1, B2, B3, B4) and advancing four CPT (CPT1, CPT2, CPT3, CPT4); •

Sampling and logging of the subsurface soils;

• Laboratory testing of selected soil samples collected from the subsurface exploration to determine the engineering properties of the soil; •

Engineering and geologic analysis of the field and laboratory data; and

• Preparation of this report presenting our findings, conclusions and recommendations for the proposed construction. 1.3

SITE DESCRIPTION

The project site is located in the City of Los Angeles just north of Beverly Hills High School at the southwest corner of Moreno Drive and Santa Monica Boulevard (Figure 1). An aerial photograph is included as Figure 2 and a topographic map is included as Figure 3. Figure 3 also shows the locations of a storm drain line and a sewer line easement located along the east side of the property. The site is currently vacant following demolition of the previous office building. Santa Monica Boulevard descends gently to the east and Moreno Drive descends to the south. From the northwest corner to the southeast corner of the property the site elevation varies by 15 feet. 1.4

PROPOSED CONSTRUCTION

It is our understanding that conceptually, site development will consist of construction that may include approximately four subterranean levels of parking and a condominium tower of approximately forty stories in height.

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Figure 1. Location map of the site.


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Figure 2. Aerial Photograph of subject lot and surrounding area.


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Figure 3. Topographic map of the subject site and surrounding area. The red star is located on the subject property. The location of the storm drain is shown by the blue line and the sewer line easement is shown by the red hachured area.

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Previous Reports Research at the Los Angeles City Building and Safety Department yielded geological and soil reports for several of the surrounding high-rise developments and for the subject property. The reports for the surrounding properties indicated that the natural alluvium is relatively uniform, dense, and can support high structural loads. None of the boring logs that were reviewed and none of the reports indicated that there were any environmental concerns in the area. The reports for the surrounding buildings indicate that they are all founded on conventional foundations consisting of spread footings, driven piles, or cast-in-place caissons. The original soil and geology report prepared by Leroy Crandall and Associates for the subject property in 1958 was obtained. The report stated that old, dense, alluvium underlies the majority of the subject site except for the eastern side along Moreno Drive where 15 feet of loose fill was found. The old fill contained trash and oil saturated sand. The report stated that the older fill would be partially removed during excavation for a basement and recommended that the remaining fill be removed and new fill compacted during development. Conventional spread footings were recommended for the building foundation and caissons were used under the perimeter, property-line block wall. In 1960, a report was issued for the foundation of a proposed 14-story tower that was to be constructed along the north side of the property. Because the construction of the office building was already underway and grading for the tower foundation was not possible, cast-in-place caissons up to 48 feet in depth were reportedly going to be installed. However, the towers were never constructed and the pile clusters that were proposed were never constructed and were not found during the recent site demolition. A methane report included within the due diligence documents stated that groundwater was encountered 5 feet below the bottom of a probe drilled to 45 feet (no logs of the drilling were provided within the report); a call to the principal engineer for the project verified that groundwater was encountered at 50 feet below the ground surface. Site Demolition A site visit was conducted on May 26th, 2006. Discussion with the demolition contractor, Holcomb Engineering Contractors, Inc., revealed that no unusual subsurface conditions were encountered. Mr. Holcomb stated that the 14-story towers were never constructed and he has searched for but has not found any pile clusters.

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INVESTIGATION GENERAL

Our field investigation was performed on January 18-20, 2007, and consisted of a review of site conditions and exploration involving excavation of four borings; advancing four CPT soundings and soil sampling. Our investigation also included laboratory testing of selected soil samples. A brief summary of these various tasks are provided below. 2.2

FIELD EXPLORATION

The subsurface investigation performed at the site consisted of excavating four borings by use of a hollow-stem auger drill rig and four electronic piezocone soundings (CPT). The purpose of the borings and CPT soundings was to determine the existing subsurface conditions and to collect subsurface soil in the areas of the proposed construction and throughout the site. The borings were excavated to a maximum depth of 100.5’ below the existing ground surface. The CPT’s were pushed to a maximum depth of 100.21’ below the existing ground surface. The soil materials encountered in Borings 1-4 consisted of fill over Older Alluvium. A review of geological maps1,2 indicates that the material underlying the subject site is comprised of Alluvium of Quaternary age (Figure 4). The borings were logged by our field geologist using both visual and tactile means. Both bulk and relatively undisturbed soil samples were obtained. The approximate locations of the borings are shown on the attached site plan included in Appendix A. Detailed boring and CPT logs are presented in Appendix B. 2.3

LABORATORY TESTING

Laboratory testing was performed on representative samples obtained during our field exploration. Samples were tested for the purpose of estimating material properties for use in subsequent engineering evaluations. Testing included in-place moisture and density, maximum density, optimum moisture content, hydro-response-swell/collapse, and shear strength testing. A summary of the laboratory test results is included in Appendix C. The physical properties of the soils were tested at Soil Labworks, LLC. The undersigned geologist and engineer have reviewed the data and concur and accept it.

1

Dibblee, Thomas, 1991, Geologic Map of the Beverly Hills and Van Nuys (south ½) Quadrangles, Los Angeles County, California Map #DF-31. 2 Hoots, H.W., 1931, Geology of the eastern part of the Santa Monica Mountains, Los Angeles County, California: United States Geological Survey Professional Paper 165-C.

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Figure 4. Portion of Dibblee Geologic Map. Site is designated by a red star.

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SITE GEOLOGY, SEISMICITY, POTENTIAL HAZARDS SITE GEOLOGY

Regional geologic maps and the subsurface exploration indicated that the property is underlain by Quaternary Age Older Alluvium (Figure 4) overlain by variable amounts of fill. Descriptions of the materials encountered in our exploratory borings are described below. 3.2.1

Fill

The fill consists of fine to coarse grained silty and gravelly sand with minor amounts of clay. The color varies from light brown to brown. The fill is medium dense, moist and contains occasional construction spoils. The fill on site varied from between 2 to about 6 feet with the exception of boring four where it was found down to a depth of about thirteen feet; this is consistent with the findings of the previous site investigation reports. 3.2.2 Quaternary Alluvium The alluvium consists of admixtures of gravel, sands, silts and clays which vary from light to dark brown, gray, greenish-gray, orange-brown. The alluvium was moist to saturated, medium dense to dense, firm to stiff, containing caliche and mica. The alluvium is generally weakly horizontally layered with no significant structural planes.

3.2.3

Groundwater

Groundwater was encountered during the recent excavations and soundings at depths ranging from 35 to 50 feet below the ground surface. Historically, the highest groundwater in this area of Los Angeles is estimated to be about 25 feet below the ground surface Figure 5 (Plate 1.2, Historically Highest Groundwater Contours and Borehole Log Data Locations, Beverly Hills 7½ Minute Quadrangle in Seismic Hazard Zone Report for the Burbank Quadrangle, SHZR-023). Feffer Boring Designation B-1 B-2 B-3 B-4

Elevation of Boring 272’ 261’ 262’ 261’

Depth to Groundwater 50’ 45’ 35’ 35’

Groundwater Elevation 222’ 216’ 227’ 226’

A monitoring well/piezometer has been installed within Boring 4 so that groundwater levels can be monitored over time. A measurement taken on February 27, 2007 indicated that groundwater was 35’ below the surface level at B-4.

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3.3


SEISMICITY

A risk common to all areas of Southern California that should not be overlooked is the potential for damage resulting from seismic events (earthquakes). The site is located within a seismically active area, as is all of Southern California. Although we are not aware of any active faults on or within the immediate vicinity of the site, earthquakes generated on large regional faults such as the San Andreas and Santa Monica-Hollywood, Verdugo, Newport Inglewood and Raymond Faults could affect the site. The closest known potentially active faults to the site are the east-west trending Santa MonicaHollywood, Newport Inglewood, Verdugo and Raymond Faults. The Santa Monica Fault is located within two kilometers of the site. Since no active faults cross the property, the surface rupture hazard at the site is very low. Due to the distance from the coastline the site is not susceptible to the effects of tsunamis and seiches. Figure 3.3 of the Seismic Hazard Zone Report for the Beverly Hills Quadrangle contains ground motion values assigned by the California Geological Survey (CGS) for this area of Los Angeles. The Design Basis Earthquake (10% Exceedance in 50 years) for the study area is peak ground acceleration (PGA) of about 0.50g. The de-aggregated predominant earthquake magnitude (Mw) is 6.5. These values are average and will not necessitate unusual structural design. Groundwater maps within the referenced report indicate that historical groundwater is deeper than 25 feet. Liquefaction Liquefaction is a process that occurs when saturated sediments are subjected to repeated strain reversals during an earthquake. The strain reversals cause increased pore water pressure such that the internal pore pressure approaches the overburden pressure and the shear strength approaches zero. Liquefied soils may be subject to flow or excessive strain, which can cause settlement. Liquefaction occurs in soils below the groundwater table. Soils commonly subject to liquefaction include loose to medium dense sand and silty sand that are normally consolidated and Holocene in age. Predominantly fine-grained soils, such as silts and clay, are less susceptible to liquefaction. Generally, soils with a clay content of greater than 15 percent and/or a fines content (percent passing the 200 sieve) greater than 30 percent, are not considered subject to liquefaction. The subject property is not included within a State of California Seismic Hazard Zone for earthquake liquefaction or seismic ground deformation. This investigation has determined the clay content of the soils too high for liquefaction. Therefore, the liquefaction potential of the site is low. Similarly, hazards associated with liquefaction, such as lateral spreading, ground failure and dynamic settlement are considered low to nil. Mitigation of the liquefaction hazards are not indicated for the site.

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4.0 4.1


GEOTECHNICAL CONSIDERATIONS SUBSURFACE SOIL CONDITIONS

Subsurface materials at the site consist of older alluvium below variable amounts of fill. On the subject property there was up to thirteen feet of fill over older alluvium. Laboratory testing indicates that the alluvium at a shallow depth has a moderate to high potential for consolidation and hydrocollapse. The older alluvium at the depth of the lowest level of the subterranean garage has a low potential for consolidation and hydrocollapse. The alluvium at the subject site is competent and not subject to liquefaction or earthquake induced ground deformation. The following paragraph provides general discussions about settlement and expansive soil activity. 4.2

SETTLEMENT

Our investigation indicated that the consolidation and hydrocollapse potential of the older alluvium at the depth of the proposed subterranean garage is low. The dry densities and blow counts were high for the samples taken at depth and it is our experience that these soils have a very low potential for consolidation. Recommendations are presented below to mitigate the settlement hazard associated with consolidation of the near surface soils. 4.3

EXPANSIVE SOIL

The on-site, near surface soil was found to possess low to moderate expansive characteristics based upon expansion index testing and field soil classifications.

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CONCLUSIONS AND RECOMMENDATIONS BASIS

Conclusions and recommendations contained in this report are based upon information provided, information gathered, laboratory testing, engineering and geologic evaluations, experience, and judgment. Recommendations contained herein should be considered minimums consistent with industry practice. More rigorous criteria could be adopted if lower risk of future problems is desired. Where alternatives are presented, regardless of what approach is taken, some risk will remain, as is always the case. 5.2

SITE SUITABILITY

The site is within an area including completed housing and building developments. Geotechnical exploration, analyses, experience, and judgment result in the conclusion that the proposed development is suitable from a geotechnical standpoint. It is our opinion that the site can be improved without hazard of landslide, slippage, or settlement, and improvement can occur without similar adverse impact on adjoining properties. Realizing this expectation will require adherence to good construction practice, agency and code requirements, the recommendations in this report, and possible addendum recommendations made after plan review and at the time of construction. 5.3

SEISMIC DESIGN CONSIDERATION

It is not known if the proposed structures are going to be designed using dynamic or static analyses. Feffer Geological has not performed a site-specific seismic ground motion study or produced seismic response spectra. The following recommendations may be used for static design. As discussed before, the nearest known potentially active seismic source are the Santa MonicaHollywood, Newport Inglewood, Verdugo and Raymond Faults. These faults are Type B faults. The soil profile of the site is characterized as SD (stiff soil). The following seismic design parameters are recommended according to Chapter 16 of the 2002 Edition of the County of Los Angeles Building Code. Soil Profile Type : SD Seismic Zone Factor (z)

: 0.4

Seismic Source Type

:B

Near-Source Factor, Na

: 1.3

Near-Source Factor, Nv

: 1.6

Seismic Coefficient, Ca Seismic Coefficient, Cv

: 0.44Na : 0.64Nv

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It should be realized that the purpose of the seismic design utilizing the above parameters is to safeguard against major structural failures and loss of life, but not to prevent damage altogether. Even if the structural engineer provides designs in accordance with the applicable codes for seismic design, the possibility of damage cannot be ruled out if moderate to strong shaking occurs as a result of a large earthquake. This is the case for essentially all structures in Southern California. 5.4

EARTHWORK

5.4.1

General

Demolition of the previous structures disturbed the upper five to fifteen feet of existing fill and alluvium; all foundations should be founded on firm undisturbed older alluvium. Remedial grading is not anticipated for subterranean levels that penetrate the existing disturbed earth materials and are founded in competent older alluvium. Portions of the proposed floor slabs and structures that penetrate the surficial materials may be founded on firm undisturbed older alluvium. Where a compacted fill cap is used it should extend at least two feet below the building slabs. If it is anticipated that the proposed construction may require grading of the site, it should be done in accordance with good construction practice, minimum code requirements and recommendations to follow. Grading criteria are included within Appendix E. 5.4.2 Site Preparation and Grading Based on our understanding of the proposed development, we recommend that footings be founded in firm older alluvium. Prior to the start of grading operations, utility lines within the project area, if any, should be located and marked in the field so they can be rerouted or protected during site development. All debris and perishable material should be removed from the site. No permanent cut and fill slopes should be constructed steeper than a 2:1 gradient. If fill is to be placed the upper six to eight inches of surface exposed by the excavation should be scarified; moisture conditioned to two to four percent over optimum moisture content, and compacted to 95 percent relative compaction3. If localized areas of relatively loose soils prevent proper compaction, over-excavation and re-compaction will be necessary.

3

Relative compaction refers to the ratio of the in-place dry density of soil to the maximum dry density of the same material as obtained by the "modified proctor" (ASTM D1557) test procedure.

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5.5.1


New Structures

All proposed footings shall be embedded within approved firm older alluvium, in accordance with the recommendations below. Formal design parameters, such as the anticipated structural loads and the depth of the basement have not been provided. Foundations loads are anticipated to be very high. The following design parameters assume that the lower subterranean level will extend 40 feet below existing grade. Based on the anticipation of high structural loads conventional column foundations and slabs are not feasible and a mat foundation is likely. Based upon the recently measured groundwater levels of 35 to 50 feet below grade, and the historically highest groundwater reported for the site of 25 feet, either permanent dewatering or a hydrostatic design will be required. Since it is not likely tenable to permanently pump groundwater to maintain the static level below the elevation of the deepest foundation and slab, a hydrostatic design is appropriate. Mat Foundations A mat foundation may be used to distribute concentrated loads to the bearing soils to mitigate differential settlement. The thickness of the mat should be determined by the structural engineer. For capacity of the mat, a net dead-plus-live load pressure of 6,000 pounds per square foot may be assumed for the native alluvium at the basement level. A ⅓ increase may be used for wind or seismic loads. For bearing calculations, the weight of the concrete in the footing may be neglected. A coefficient of subgrade reaction of 335 kips per cubic foot may be used for the mat to compute deflections. The recommended subgrade modulus has already been factored to reflect the anticipated size.

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5.6


RETAINING WALL AND SHORING

Retaining Wall Cantilevered retaining walls up to 20 feet high that support older alluvium and approved retaining wall backfill, may be designed for an equivalent fluid pressure of 45 pounds per cubic foot (calculations included within Appendix D). Restrained basement walls that are pinned at the top by a non-yielding floor should be designed for a trapezoidal distribution of pressure. The design earth pressure on restrained basement wall is 30H psf, where H is the height of the basement wall in feet. Retaining walls should be provided with a subdrain or weepholes covered with a minimum of 12 inches of ¾ inch crushed gravel.

28H

Basement retaining walls surcharged by existing foundations or vehicular traffic should be designed to withstand the surcharge. Feffer Geologic would be happy to assist the structural engineer in evaluating the magnitude of the surcharge pressure and the point of application. Backfill Retaining wall backfill should be compacted to a minimum of 90 percent of the maximum density as determined by ASTM D 1557-02. Where access between the retaining wall and the temporary excavation prevents the use of compaction equipment, retaining walls should be backfilled with ¾ inch crushed gravel to within 2 feet of the ground surface. Where the area between the wall and the excavation exceeds 18 inches, the gravel must be vibrated or wheel-rolled, and tested for compaction. The upper 2 feet of backfill above the gravel should consist of a compacted fill blanket to the surface. Retaining wall backfill should be capped with a paved surface drain or a concrete slab. It should be pointed out that the use of heavy compaction equipment in close proximity to retaining walls can result in excess wall movement and/or soil loadings exceeding design values. In this regard, care should be taken during backfilling operations.

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Waterproofing Where retaining walls form portions of the building interiors, very special consideration should be given to waterproofing the walls to prevent damage to the building interior. Unless dampness is acceptable on exterior wall faces, waterproofing should also be incorporated into the exterior retaining wall design. Although the project architect is the party who should provide actual waterproofing details, it is suggested the waterproofing consist of a multi-layered system such as an initial generously applied layer of hot-mopped asphalt over which a layer of construction felt could be applied, then thoroughly mopped again with hot asphalt. In the case of all retaining walls, it is suggested that a layer of 10-mil Visqueen be placed as a finish layer. The multi-layered system should be covered with protective foam board, or similar, to prevent damage during the backfilling operation. Extreme care should be exercised in sealing walls against water and water vapor migration. Where retaining walls are planned against interior space, continuity should be provided between the aforementioned wall moisture-proofing on the back of the retaining wall and the moisture barrier typically placed under slab areas. This waterproofing is necessary to prevent the foundation concrete from acting as a wick through which moisture migrates to the interior space despite wall moisture proofing. As aforementioned, the architect or structural engineer should develop the actual waterproofing details. 5.6.2 TEMPORARY EXCAVATIONS Temporary excavations will be required to construct the proposed subterranean levels. The excavations could be up to 50 feet in height and will expose scattered fill over Older Alluvium. Where not surcharged by existing footings or structures, the Older Alluvium is capable of maintaining vertical excavations up to 5 feet. Where vertical excavations in the Older Alluvium exceed 5 feet in height, the upper portion should be trimmed to 1:1 (45 degrees). Vertical excavations removing lateral or vertical support from existing structures or the public right-of-way will require the use of temporary shoring. Any excavation that encroaches within a 1:1 plane projected downward from the edge of the footing is considered to remove lateral support from the footing. Shoring Shoring may consist of drilled, cast-in-place concrete piles with wood lagging. Shoring piles should be a minimum of 24 inches in diameter and a minimum of 8 feet into native soils below the base of the excavation. Piles may be assumed fixed at 3 feet below the base of the excavation. The concrete placed in the soldier pile excavations may be a lean-mix concrete. However, the concrete used in that portion of the soldier pile, which is below the planned excavated level, should be of sufficient strength to adequately transfer the imposed loads to the surrounding soils. Cantilevered shoring up to a height of 20 feet may be designed for an equivalent fluid pressure of 35 pcf. The recommended design pressure on shoring in excess of 20 feet is 40 pcf. For the vertical forces, piles may be designed for a skin friction of 200 pounds per square foot for that portion of pile

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in contact with the soil. Soldier piles should be spaced a maximum of 8 feet on center. Due to arching on the soils, the design fluid pressure should be multiplied by the pile spacing. Shoring that is restrained by tie-back anchors, rakers or struts should be designed for a trapezoidal distribution of soil pressure. The design earth pressure on restrained shoring wall is 22H psf, where H is the height of the shored excavation wall in feet. The recommended soil pressures do not include surcharge pressures from traffic or existing structures. The shoring engineer should add appropriate surcharge pressures to account for existing structures, property line retaining walls and vehicular traffic. Feffer Geological can assist the shoring engineer in determining the surcharge pressure and the point of application. Lateral Design of Shoring The friction value is for the total of dead and frequently applied live loads and may be increased by one third for short duration loading, which includes the effects of wind or seismic forces. Resistance to lateral loading may be provided by passive earth pressure within the Older Alluvium below the base of the excavation. Passive earth pressure may be computed as an equivalent fluid having a density of 300 pounds per cubic foot. The maximum allowable earth pressure is 6,000 pounds per square foot. For design of isolated piles, the allowable passive and maximum earth pressures may be increased by 100 percent. Piles spaced more than 2½ pile diameters on center may be considered isolated. Lagging Lagging is required between shoring piles. The lagging should be designed for a maximum pressure of 400 pounds per square foot. Earth Anchors Earth anchors (tie backs) may be employed to assist the shoring system. Pressure grouted friction anchors are recommended. For design purposes, it is assumed that the active wedge adjacent to the shoring is defined by a plane drawn at 30 degrees with the vertical through the bottom excavation. Friction anchors should extend at least 20 feet beyond the potential active wedge, or to a greater length if necessary to develop the desired capacities. The capacities of the anchors should be determined by testing of the initial anchors as outlined in a following section. For shallow conventional, straight-shaft friction anchors (less than 15 feet of over-burden) the estimated skin friction is 300 pounds per square foot. Deeper anchors will develop an average value of 550 to 750 pounds per square foot. Post-grouted anchors are expected to achieve capacities of 3 to 8 kips/ft, depending on the depth. Only the frictional resistance developed beyond the active wedge would be effective in resisting lateral loads. If the anchors are spaced at least six feet on center, no reduction in the capacity of the anchors need be considered due to group action. The anchors may be installed at angles of 20 to 40 degrees below the horizontal. Caving and sloughing of the anchor hole should be anticipated and provisions made to minimize such caving and

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sloughing. To minimize chances of caving and sloughing, that portion of the anchor shaft within the active wedge should be backfilled with sand before testing the anchor. This portion of the shaft should be filled tightly and flush with the face of the excavation. The sand backfill should be placed by pumping; the sand may contain a small amount of cement to facilitate pumping. The frictional resistance between the soldier piles and the retained earth may be used in resisting a portion of the downward component of the anchor load. The coefficient of friction between the soldier piles and the retained earth may be taken as 0.25. (This value is based on the assumption that uniform full bearing will be developed between the steel soldier beam and the lean-mix concrete and between the lean-mix concrete and the retained earth). In addition, the soldier piles below the excavated level may be used to resist downward loads. The downward frictional resistance between the concrete soldier piles and the soils below the excavated level may be taken as equal to 200 pounds per square foot. The initial anchors should be performance tested to verify the design assumptions and capacities. The shoring engineer should specify a testing program that is acceptable to the geotechnical engineer. The following may be used as a guide. Three of the initial anchors should be scheduled for a 24-hour 200 percent test and 10 percent of the remaining anchors for quick 200 percent tests. The specific anchors selected for the 200 percent test should be representative and acceptable to the geotechnical engineer. The purpose of the 200 percent tests is to verify the friction value assumed in design and the bond length. Anchor rods of sufficient strength should be installed in these anchors to support the 200 percent test loading. Where satisfactory tests are not achieved on the initial anchors, the anchor diameter and/or length should be increased until satisfactory test results are obtained. The total deflection during the 24-hour 200 percent test should not exceed 12 inches. During the 24-hour test, the anchor deflection should not exceed 0.75 inches, measured after the 200 percent test load is applied. If the anchor movement after the 200 percent load has been applied for 12 hours is less than 0.5 inches, and the movement over the previous four hours has been less than 0.1 inches, the 24-hour test may be terminated. For the quick 200 percent tests, the 200 percent test load should be maintained for 30 minutes. The total deflection of the anchor during the 200 percent quick tests should not exceed 12 inches; the deflection after the 200 percent test load has been applied should not exceed 0.25 inch during the 30minute period. All of the anchors should be proof tested to at least 150 percent of the design load. Total deflection during the test should not exceed 12 inches. The rate of creep under the 150 percent test should not exceed 0.1 inch over a 15-minute period for the anchor to be approved for the design loading. After a satisfactory test, each anchor should be locked-off at the design load. The locked-off load should be verified by rechecking the load in the anchor. If the locked-off load varies by more than 10 percent from the design load, the load should be reset until the anchor is locked-off within 10 percent of the design load. The installation of the anchors and the testing of the completed anchors should be observed by a representative of the geotechnical engineer.

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Deflection Monitoring Some deflection is expected for a well designed and constructed shoring system. Where offsite structures or the public right-of-way are located within 10 feet of the shored excavation, it is recommended that the deflection be limited to ½ inch or less. Where offsite structures and the public right-of-way are located within more than 10 feet of the shored excavation, it is recommended that the deflection be limited to 1 inch or less. Prior to construction and excavation for the subterranean levels, it is recommended that the existing conditions along the property line be documented and surveyed. Documentation should include photographs and descriptions of the offsite structures and conditions. Survey monuments should be affixed to representative structures and to points along the property line and offsite. The survey points should be measured prior to construction to form a baseline for determining settlement or deformation. Upon installation of the soldier piles, survey monuments should be affixed to the tops of representative piles so that deflection can be measured. The shored excavation and offsite structures should be visually inspected every day. Survey monuments should be measured once a month during the construction process. Should the surveys reveal offsite deformation or excessive deflection of the shoring system, the shoring engineer and geotechnical engineer should be notified. Excessive deflection may require additional anchors, postgrouting and re-tensioning or internal bracing to restrain the shoring system. Excavation Characteristics The borings and CPT soundings did not encounter hard, cemented bedrock. Groundwater was encountered at depths of 35 to 50 feet and should be anticipated for drilled shafts and deep excavations. Drilled foundations and anchors below the groundwater level may be subject to caving and casing, drilling muds or special drilling techniques may be required. Water should be pumped from foundation excavations prior to placing concrete. As an alternative, water may be displaced from drilled foundation shafts by placing the concrete from the bottom up. The compressive strength of concrete placed below the water table should be increased by 1,000 psi over the design strength. A dewatering consultant should be retained to evaluate the feasibility of lowering the groundwater table to facilitate construction. 5.7

EXTERIOR FLATWORK

Whenever planned, the exterior flatwork should be placed over at least a two foot blanket of approved compacted fill. Five inch net sections with #4 bars at 18 inches o.c.e.w. are also advised. Control joints should be planned at not more than twelve foot spacing for larger concrete areas. Narrower areas of flatwork such as walkways should have control joints planned at not greater than 1.5 times the width of the walkway. Recommendations provided above for interior slabs can also be used for exterior flatwork, but without a sand layer or Visqueen moisture barrier. Additionally, it is also recommended that at least 12-inch deepened footings be constructed along the edges of larger concrete areas.

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Movement of slabs adjacent to structures can be mitigated by doweling slabs to perimeter footings. Doweling should consist of No. 4 bars bent around exterior footing reinforcement. Dowels should be extended at least two feet into planned exterior slabs. Doweling should be spaced consistent with the reinforcement schedule for the slab. With doweling, 3/8-inch minimum thickness expansion joint material should be provided. Where expansion joint material is provided, it should be held down about 3/8 inch below the surface. The expansion joints should be finished with a color matched, flowing, flexible sealer (e.g., pool deck compound) sanded to add mortar-like texture. As an option to doweling, an architectural separation could be provided between the main structures and abutting appurtenant improvements. 5.8

CONCRETE

Based on our experience soils at the site have low levels of sulfates. As such, no special sulfate resistant cure mix design is required for the project. However, we recommend that the low permeable concrete be utilized at the site to limit moisture transmission through slab and foundation. For this purpose, the water/cement ratio to be used at the site should be limited to 0.5 (0.45 preferred). Limited use (subject to approval of mix designs) of a water reducing agent may be included to increase workability. The concrete should be properly cured to minimize risk of shrinkage cracking. The code dictates at least seven days of moist curing. Two to three weeks is preferred to minimize cracking. One-inch hard rock mixes should be provided. Pea gravel mixes are specifically not recommended but could be utilized for relatively non-critical improvements (e.g., flatwork) and other improvements provided the mix designs consider limiting shrinkage. Contractors/other designers should take care in all aspects of designing mixes, detailing, placing, finishing, and curing concrete. The mix designers and contractor are advised to consider all available steps to reduce cracking. The use of shrinkage compensating cement or fiber reinforcing should be considered. Mix designs proposed by the contractor should be considered subject to review by the project engineer. 5.9

DRAINAGE

Drainage should be directed away from structures via non-erodible conduits to suitable disposal areas. Two percent drainage is recommended directly away from structures. Two percent minimum is recommended for drainage over soil areas. In pipes or paved swales, one percent should be adopted as the minimum unless otherwise recommended by the project civil engineer. For area drains, a six inch minimum pipe diameter is recommended because experience has shown that three and four-inch pipes tend to clog. All enclosed planters should be provided with a suitably located drain or drains and/or flooding protection in the form of weep holes or similar. Preferably, structures should have roof gutters and downspouts tied directly to the area drainage system. 5.10

PLAN REVIEW

When detailed grading and structural plans are developed, they should be forwarded to this office for review and comment.

File No.494-64 March 24, 2007

5.11


AGENCY REVIEW

All soil, geologic, and structural aspects of the proposed development are subject to the review and approval of the governing agency(s). It should be recognized that the governing agency(s) can dictate the manner in which the project proceeds. They could approve or deny any aspect of the proposed improvements and/or could dictate which foundation and grading options are acceptable.

5.12

SUPPLEMENTAL CONSULTING

During construction, a number of reviews by this office are recommended to verify site geotechnical conditions and conformance with the intentions of the recommendations for construction. Although not all possible geotechnical observation and testing services are required by the governing agencies, the more site reviews requested, the lower the risk of future site problems. The following site reviews are advised, some of which will probably be required by the agencies. Preconstruction/pregrading meeting ................................................ Advised Continuous observation and testing during any grading.................Required Shoring Observation .......................................................................Required Reinforcement for all foundations ................................................... Advised Slab subgrade moisture barrier membrane ...................................... Advised Slab subgrade rock placement ......................................................... Advised Presaturation checks for all slabs in primary structure areas..........Required Presaturation checks for all slabs for appurtenant structures........... Advised Slab steel placement, primary and appurtenant structures............... Advised Compaction of utility trench backfill............................................... Advised Unless otherwise agreed to in writing, all supplemental consulting services will be provided on an as-needed, time-and-expense, fee schedule basis. 5.13

PROJECT SAFETY

The contractor is the party responsible for providing a safe site. This consultant will not direct the contractor's operations and cannot be responsible for the safety of personnel other than his own representatives on site. The contractor should notify the owner if he is aware of and/or anticipates unsafe conditions. If the geotechnical consultant at the time of construction considers conditions unsafe, the contractor, as well as the owner's representative, will be notified. Within this report the terminology safe or safely may have been utilized. The intent of such use is to imply low risk. Some risk will remain, however, as is always the case.

File No.494-64 March 24, 2007

6.0


REMARKS

Only a portion of subsurface conditions have been reviewed and evaluated. Conclusions, recommendations and other information contained in this report are based upon the assumptions that subsurface conditions do not vary appreciably between and adjacent to observation points. Although no significant variation is anticipated, it must be recognized that variations can occur. This report has been prepared for the sole use and benefit of our client. The intent of the report is to advise our client on geotechnical matters involving the proposed improvements. It should be understood that the geotechnical consulting provided and the contents of this report are not perfect. Any errors or omissions noted by any party reviewing this report, and/or any other geotechnical aspect of the project, should be reported to this office in a timely fashion. The client is the only party intended by this office to directly receive the advice. Subsequent use of this report can only be authorized by the client. Any transferring of information or other directed use by the client should be considered "advice by the client." Geotechnical engineering is characterized by uncertainty. Geotechnical engineering is often described as an inexact science or art. Conclusions and recommendations presented herein are partly based upon the evaluations of technical information gathered, partly on experience, and partly on professional judgment. The conclusions and recommendations presented should be considered "advice." Other consultants could arrive at different conclusions and recommendations. Typically, "minimum" recommendations have been presented. Although some risk will always remain, lower risk of future problems would usually result if more restrictive criteria were adopted. Final decisions on matters presented are the responsibility of the client and/or the governing agencies. No warranties in any respect are made as to the performance of the project.

File No.494-64 March 24, 2007


REFERENCES 1.

Blake, T., 2000, EQFault, Version 3.00b, Program for Deterministic Estimation of Peak Acceleration from Digitized Faults.

2.

Blake, T., 2000, EQSearch, Version 3.00b, Program for Estimation of Peak Acceleration from California Earthquake Catalogs.

3.

Blake, T., 2000, UBCSEIS, Version 1.03, Program for Computation of 1997 Uniform Building Code Seismic Design Parameters.

4.

Jennings, C.W., 1994, “Fault Activity Map of California and Adjacent Areas,” Scale – 1:750,000, California Division of Mines and Geology, California Geologic Map Data Series.

5.

State of California, Seismic Hazard Zone Mapping, 1998, Beverly Hills Quadrangle.

APPENDIX ‘A’ Site Plan

LARGE GRAVEL PILE

CPT-1

FILL OVER OLDER ALLUVIUM

B-1 CPT-3

B-3

CPT-2 B-2

B-4

PROPOSED FORTY-STORY BUILDING OVER FOUR LEVELS OF SUBTERRANEAN PARKING

CPT-4

SITE PLAN JB:

494-64

NAME:

SUNCAL CO.

BY:

YH

10000 SANTA MONICA BLVD BASE MAP FROM S.E.C. CIVIL ENGINEERS SURVEY

DATE:

3/24/07 SCALE:1”=30’

SITE:

REF:

LEGEND B-4 LOCATION OF BORING CPT-4 LOCATION OF CPT

APPENDIX ‘B’ Boring Logs & CPT Logs

LOG OF EXPLORATORY BORING Job Number: Project: Sun

494-64 Cal Co

Boring No: 1 Boring Location: See Drill Type:

Site Plan for location

8” Hollow Stem Rig

Moisture

Density

Bulk

Color

Sample Type Undisturbed

Blows per Foot

Date Performed: 1/20/07

Depth in Feet

Sheet 1 of 3

Bedrock/ Soil Description

brown

Fill: Silty sand, fg

5

8 9 R 11

10

4 7 11

15

10 12 R 16

20

4 5 8

SPT

SPT

Silty sand with gravel, mg-cg

brown

Alluvium: Silty sand, with gravel, fg-mg, clay binder

Silty sand to clay sand, fg

medium dense

moist

dense

mottled orange, brown dense to firm greenish-gray

Sandy silt, fg

dense

25

7 12 R 14

Interbedded silty sand and silty clay, fg

orange gray-brown

30

7 11 14

Silty sand, fg-mg, with gravel

brown red-brown

35

17 20 R 22

SPT

slightly moist

mottled brown, gray

Clayey silt, fg

40

Feffer Geological Consulting

Figure


494-64 Cal Co




Moisture

Density

Bulk

Color


Blows per Foot


Depth in Feet

Sheet 2 of 3


40

6 9 10

SPT

45

16 22 R 25

50

6 10 11

55

4 5 8

SPT

R

Silty sand, mg-cg, with clay binder

Silty clay to clay silt, fg

mottled brown green-brown

Water, interbeded gravelly sand and silty sand, mg-fg

brown red-brown

Gravelly sand, cg, cohesionless

brown

60

5 8 13

65

22 50 R

sandy clay, fg, calèche

70

5 10 13

75

21 27 R 30

SPT

SPT

brown

dense

moist

saturated

medium dense medium dense to dense

Interbeded silty sand, fg, and gravelly sand, cg, gravelly sand is cohesionless gray

stiff

Silty sand to sandy silt, fg-mg, with occasional gravel, calèche

mottled orange-brown gray-brown

dense

Silty sand to sandy silt, fg, calèche

mottled brown gray-green

moist

80


Figure


Boring No: 1 Boring Location: See

494-64 Cal Co

Drill Type:



Moisture

Density

Bulk

Color


Blows per Foot


Depth in Feet

Sheet 3 of 3


80

12 15 22

SPT

Sandy silt to silty sand, fg, calèche

85

25 R 50

Sandy silt, fg, calèche

90

13 15 17

Interbeded sandy clay and sand, fg, calèche

95

22 R 50

100

105

7 8 15

SPT

SPT

brown

dense

moist

gray brown

Clay, fg, poor recovery

brown

Silty clay, fg

mottled gray-green brown

stiff

End at 100’ Fill to 10’ Water at 50’, No Caving

110

115

120


Figure



494-64 Cal Co

Drill Type:



Moisture

Density

Bulk

Color


Blows per Foot


Depth in Feet

Sheet 1 of 3


brown

Fill: Silty sand, fg

5

10 15 R 17

Alluvium: Interbedded sandy silt and silty sand with gravel, fg-mg, clay binder

10

5 6 9

Silty clay, fg

15

9 12 R 15

20

4 5 7

SPT

SPT

dense

moist

firm to stiff

Silty sand, fg, clay binder

mottled orange-brown greenish-gray brown

Sandy silt, fg

25

8 12 R 15

Sandy silt to clayey silt, fg, occasional gravel & slate chips

30

14 18 30

Silty sand grades into gravelly sand, mg-cg, gravel up to 1/2”

35

20 22 R 28

SPT

brown, gray brown, green brown

slightly moist

Silty sand to sandy silt, fg, occasional gravel

dense medium dense

dense

brown

brown orange-brown

40


Figure


494-64 Cal Co




Moisture

Density

Bulk

Color


Blows per Foot


Depth in Feet

Sheet 2 of 3


40

6 8 11

SPT

Clayey silt, fg, occasional gravel

mottled orange-brown gray-green brown

dense

45

14 20 R 28

Water, No recovery

50

50 for 6”

Gravelly sand, cg, rock fragments up to 1”

brown red-brown

55

23 R 30

Gravelly sand, mg, grades into sandy clay, mg

green-gray

dense to firm

60

15 18 25

Silty sand to clay sand, fg-mg

mottled green-gray red-brown brown

dense

65

25 55 R

Gravelly sand, cg, clay binder, slate chips up to 3/4”

red-brown gray-brown brown

70

10 15 19

75

20 23 R 28

SPT

SPT

SPT

Silty sand with gravel, mg-cg, slate chips, calèche

Silty sand to clay sand with gravel up to 1/16”, calèche

moist

saturated

moist

brown

dense to stiff

80


Figure



494-64 Cal Co

Drill Type:



Density

brown green-brown

dense

Moisture

Color

Bulk


Blows per Foot


Depth in Feet

Sheet 3 of 3


80

13 19 20

SPT

85

17 20 R 23

90

12 14 19

R

95

100

105

SPT

29 50

SPT

Sandy silt to silty sand, fg, clay binder

moist

mottled orange-brown gray-green brown

Silty sand, fg-mg

Silty sand, fg-mg, calèche, occasional gravel Silty sand to sandy silt, fg

Interbeded silty sand, fg, and gravelly sand, cg

mottled green-gray brown brown

saturated

End at 100’ Fill to 5’ Water at 45’, No Caving

110

115

120


Figure


494-64 Cal Co




Color

Density

Moisture

Bulk


Blows per Foot


Depth in Feet

Sheet 1 of 2

orange-brown gray, brown

dense

moist


Fill: Silty sand with gravel 5

10

26 55 R

Alluvium: Gravelly sand, cg, gravel up to ½”

15 17 R 19

Interbeded clay sand and silty sand

brown

15

10 12 R 15

Silty clay, fg, with occasional gravel

mottled gray orange-brown green-brown

20

13 15 R 17

Silty clay, fg

mottled orange-brown brown

25

17 19 R 20

Clayey silt to silty clay, fg

30

14 17 R 18

Silty sand to sandy silt, fg-mg, with gravel up to 3/4”

mottled red-brown black, gray

35

20 21 R 23

Water, Gravely sand, mg-cg, clay binder, gravel up to 3/4”

brown red-brown

firm to dense

firm to stiff

green-gray

dense

saturated

40


Figure


494-64 Cal Co




Density

Moisture

Bulk

Color


Blows per Foot


Depth in Feet

Sheet 2 of 2

dense

saturated


40

45

50

55

21 R 24 28 9 15 R 18 14 16 R 20

Gravely sand, cg, cohesionless, clay inclusions, gravel up to 1/2”

brown

Gravely sand, cg, cohesionless, clay inclusions, gravel up to ½”no recovery,

Clay sand, cg, with gravel

dense to stiff

End at 50’, Fill to 5’ Water at 35’, No Caving

60

65

70

75

80


Figure


494-64 Cal Co




Density

Moisture

Bulk

Color


Blows per Foot


Depth in Feet

Sheet 1 of 2

dense

moist


Fill: Silty sand with gravel 5

14 15 R 17

Gravelly sand, cg, cohesionless

10

26 50 R

Gravelly sand, cg, cohesionless, concrete debris

15

12 14 R 17

Alluvium: Silty sand, mg-cg, with gravel

20

14 15 R 16

Sandy silt, fg, with clay binder

25

8 10 R 11

Clayey silt, fg

30

7 12 R 14

Gravely sand, mg-cg, cohesionless, clay inclusions

35

17 23 R 28

brown, tan

mottled orange brown gray brown greenish gray-brown

Water, Gravely sand, mg-cg, cohesionless, gravel up to 1/4”

slightly moist to moist

light brown gray

brown black orange brown

moist

dense to firm dense

saturated

40


Figure


494-64 Cal Co




Density

Moisture

Bulk

Color


Blows per Foot


Depth in Feet

Sheet 2 of 2

dense

saturated


40

45

21 R 24 28 9 15 R 18

50

14 16 R 20

55

14 17 R 22

60

14 15 R 19

Gravely sand, mg-cg, cohesionless, gravel up to 1/4”

brown

Gravely sand, cg, cohesionless, poor recovery in rings, bag sample only

Gravely sand, cg, cohesionless, clay inclusions, poor recovery in rings, bag sample only Gravelly sand, mg-cg, clay inclusions, cohesionless

Gravelly sand, mg-cg, clay inclusions, cohesionless End at 60’, Fill to 15’ Water at 35’, No Caving

65

70

75

80


Figure

Kehoe Testing & Engineering Office: (714) 901-7270 Fax: (714) 901-7289 [email protected] Tip Stress COR 0

(tsf)

0

CPT Data 30 ton rig Customer: Feffer Geological Job Site: Vacant Lot

Sleeve Stress 700

0

(tsf)

Date: 18/Jan/2007 Test ID: CPT-1 Project: LosAngeles

Pore Pressure 10

-1

(tsf)

Ratio COR 30

0

(%)

SBT FR 8

2

(Rob. 1986) 12 Interbedded

0

Sand Mix Silt Mix Clay Organics Clay Silt Mix

10

10

Clay Sand Mix Silt Mix

Clay

20

20

Depth (ft)

Silty Clay

Clay

30

30 Silty Clay

40

40 Silt Mix

50

50 Maximum depth: 100.09 (ft) Page 1 of 3

Test ID: CPT-1

File: Z18J0707C.ECP


(tsf)


Sleeve Stress 700

0

(tsf)


Pore Pressure 10

-1

(tsf)

Ratio COR 30

0

(%)

SBT FR 8

2

(Rob. 1986) 12

50

50 Silt Mix Silty Sand Sand

60

60 Sandy Silt

Silt Mix VS Fine Gr

70

70

Depth (ft)

Silt Mix

Sandy Silt

80

80

VS Fine Gr Silt Mix

Sandy Silt

90

90

Sandy Silt

Silt Mix

100


Test ID: CPT-1

File: Z18J0707C.ECP


(tsf)


Sleeve Stress 700

0

(tsf)


Pore Pressure 10

-1

(tsf)

Ratio COR 30

0

(%)

SBT FR 8

2

(Rob. 1986) 12 100

110

110

120

120

130

130

140

140

Depth (ft)

100

150


Test ID: CPT-1

File: Z18J0707C.ECP


(tsf)


Sleeve Stress 700

0

(tsf)


Pore Pressure 10

-1

(tsf)

Ratio COR 30

0

(%)

SBT FR 8

2

(Rob. 1986) 12

0

0 Interbedded Silt Mix Clay Silty Clay Sandy Silt Silty Clay Sandy Silt

10

10

Silt Mix Silty Clay Silt Mix Silty Clay

20

20

Depth (ft)

Silt Mix

Silty Clay Clay

Silt Mix

30

30

Clay

Silt Mix

Silty Clay

40

40

Silt Mix

Sandy Silt Gr Sand Sandy Silt Sand

50


Test ID: CPT-2

File: Z18J0703C.ECP


(tsf)

50


Sleeve Stress 700

0

(tsf)


Pore Pressure 10

-1

(tsf)

Ratio COR 30

0

(%)

SBT FR 8

2

(Rob. 1986) 12 Sand

50

Silt Mix

Sandy Silt

60

Silt Mix

60

Sandy Silt Silt Mix VS Fine Gr

70

70

Depth (ft)

Silt Mix

80

Sandy Silt

80

Silt Mix Sandy Silt

90

90 Silt Mix

Sandy Silt

100


Test ID: CPT-2

File: Z18J0703C.ECP


(tsf)


Sleeve Stress 700

0

(tsf)


Pore Pressure 10

-1

(tsf)

Ratio COR 30

0

(%)

SBT FR 8

2

(Rob. 1986) 12 100

110

110

120

120

130

130

140

140

Depth (ft)

100

150


Test ID: CPT-2

File: Z18J0703C.ECP


(tsf)


Sleeve Stress 700

0

(tsf)


Pore Pressure 10

-1

(tsf)

Ratio COR 30

0

(%)

SBT FR 8

2

(Rob. 1986) 12

0

0 Sand Sandy Silt Clay Sand Mix Silty Clay Sandy Silt Silt Mix Sandy Silt Silty Clay

10

10

Silty Clay Silt Mix

Silty Clay

20

20

Depth (ft)

Silty Sand Sandy Silt Silty Clay Silt Mix

30

30 Clay Silty Clay Clay Sand Mix Silty Sand Sand Mix

40

40

Silty Sand Clay

Silt Mix

50


Test ID: CPT-3

File: Z18J0705C.ECP


(tsf)

50


Sleeve Stress 700

0

(tsf)


Pore Pressure 10

-1

(tsf)

Ratio COR 30

0

(%)

SBT FR 8

2

(Rob. 1986) 12 Silt Mix Sand

50

VS Fine Gr Clay Sand VS - Sandy

60

Silty Sand Gr Sand Sand

70

60

70

Depth (ft)

Silt Mix

80

80

Sandy Silt

90

90 Silt Mix

Sandy Silt

Silt Mix

100


Test ID: CPT-3

File: Z18J0705C.ECP


(tsf)


Sleeve Stress 700

0

(tsf)


Pore Pressure 10

-1

(tsf)

Ratio COR 30

0

(%)

SBT FR 8

2

(Rob. 1986) 12 100

110

110

120

120

130

130

140

140

Depth (ft)

100

150


Test ID: CPT-3

File: Z18J0705C.ECP


(tsf)

0


Sleeve Stress 700

0

(tsf)


Pore Pressure 10

-1

(tsf)

Ratio COR 30

0

(%)

SBT FR 8

2

(Rob. 1986) 12 Silt Mix

0

Clay

Silty Clay

10

10

Sand Mix VS - Sandy VS Fine Gr

20

20

Depth (ft)

Silty Clay

Clay

30

30 VS Fine Gr Silty Sand Sand Mix VS - Sandy VS Fine Gr

40

40

VS - Sandy

Silty Sand VS Fine Gr Silty Sand VS Fine Gr

50

50

Maximum depth: 100.17 (ft) Page 1 of 3

Test ID: CPT-4

File: Z18J0706C.ECP


(tsf)


Sleeve Stress 700

0

(tsf)


Pore Pressure 10

-1

(tsf)

Ratio COR 30

0

(%)

SBT FR 8

2

(Rob. 1986) 12

50

50 VS Fine Gr Silty Sand Sandy Silt

60

60

Silt Mix

70

Depth (ft)

70 VS Fine Gr

Silt Mix

80

80 Sandy Silt

Silt Mix

90

90 Sandy Silt

Silt Mix

100


Test ID: CPT-4

File: Z18J0706C.ECP


(tsf)


Sleeve Stress 700

0

(tsf)


Pore Pressure 10

-1

(tsf)

Ratio COR 30

0

(%)

SBT FR 8

2

(Rob. 1986) 12 100

110

110

120

120

130

130

140

140

Depth (ft)

100

150


Test ID: CPT-4

File: Z18J0706C.ECP

APPENDIX ‘C’ Laboratory Testing

APPENDIX ‘D’ Engineering Calculations

NAVFAC DENSITY IC: CLIENT:

CONSULT: 494-64 SUNCAL COMPANIES

GRAPH #

1

JAI

ESTIMATED COMPACTNESS FROM SPT BLOW COUNTS MODIFIED FROM NAVFAC FIG. 1 7.1-14 140 CPT-1 CPT-2

N60 BLOW COUNTS (blows/ft)

69.104 101.477

80

1.432 0.449

0.471 1.426 1.825 2.562 3.413 3.42 3.734 4.024

40 FEET

1.492 CPT-4 2.861 2.26 1.019 0.678 0.433 0.485 0.599

30 FEET

CPT-3

12024.073 28.675 24.334 14.66 13.211 10.214 10012.815 13.529

VERY DENSE

3.758 -3.528

DENSE

60

40 MEDIUM

20 LOOSE

VERY LOOSE

0 0.0

0.5

1.0 1.5 2.0 2.5 3.0 VERTICAL EFFECTIVE STRESS (tsf)

3.5

4.0

SHEAR WAVE VELOCITY JN: CLIENT:

CONSULT: 494-64 SUNCAL COMPANIES

GRAPH #

INTERNAL SHEAR WAVE VELOCITY 1700 CPT-2 - SEISMIC

1500

S-WAVE VELOCITY (ft/sec)

1300

SOIL PROFILE TYPE S C 1100

SOIL PROFILE TYPE S D

900

700

500

300 0

20

40

DEPTH (feet)

60

80

100

JF

CPT/SPT BLOW COUNT CONSULT: 494-64 SUNCAL COMPANIES

IC: CLIENT:

CORRELATION SHEET #

JAI

1

SPT N60 BLOW COUNT CORRELATION

100 CPT-1 Boring 1

90

BLOW COUNTS (N60)

80 70 60 50 40 30 20 10 0 0

20

40

60

DEPTH (feet)

80

100

CPT/SPT BLOW COUNT CONSULT: 494-64 SUNCAL COMPANIES

IC: CLIENT:

CORRELATION SHEET #

JAI

2

SPT N60 BLOW COUNT CORRELATION

100 CPT-2 Boring 2

90

BLOW COUNTS (N60)

80 70 60 50 40 30 20 10 0 0

20

40

60

DEPTH (feet)

80

100

FOUNDATION SETTLEMENT CONSULT: 494-64 SUNCAL COMPANIES

IC: CLIENT:

JAI

CALCULATION SHEET #

TOTAL SETTLEMENT-CONSTRAINED MODULUS MAT FOUNDATION (40' DEEP - 6,000 PSF) 0.80

CPT-1 CPT-2 0.70

CPT-3 CPT-4

TOTAL SETTLEMENT (inches)

0.60

0.50

0.40

0.30

0.20

0.10

0.00 0

20

40

60

DEPTH (feet)

80

100

RETAINING WALL IC: CLIENT:

CONSULT: JF 494-64 FEFFER/SUNCAL COMPANIES

CALCULATION SHEET #

1

CALCULATE THE DESIGN MINIMUM EQUIVALENT FLUID PRESSURE (EFP) FOR PROPOSED RETAINING WALLS. THE WALL HEIGHT AND BACKSLOPE AND SURCHARGE CONDITIONS ARE LISTED BELOW. ASSUME THE BACKFILL IS SATURATED WITH NO EXCESS HYDROSTATIC PRESSURE. USE THE MONONOBE-OKABE METHOD FOR SEISMIC FORCES.

CALCULATION PARAMETERS EARTH MATERIAL: ALLUVIUM WALL HEIGHT B-1 SHEAR DIAGRAM: BACKSLOPE ANGLE: SURCHARGE: COHESION: 280 psf PHI ANGLE: SURCHARGE TYPE: 27 degrees DENSITY INITIAL FAILURE ANGLE: 125 pcf SAFETY FACTOR: 1.5 FINAL FAILURE ANGLE: 0 degrees INITIAL TENSION CRACK: WALL FRICTION CD (C/FS): 186.7 psf FINAL TENSION CRACK: PHID = ATAN(TAN(PHI)/FS) = 18.8 degrees HORIZONTAL PSEUDO STATIC SEISMIC COEFFICIENT (k h) 0 %g VERTICAL PSEUDO STATIC SEISMIC COEFFICIENT (k v) 0 %g

20 0 1000 P 10 70 4 40

CALCULATED RESULTS CRITICAL FAILURE ANGLE AREA OF TRIAL FAILURE WEDGE TOTAL EXTERNAL SURCHARGE WEIGHT OF TRIAL FAILURE WEDGE NUMBER OF TRIAL WEDGES ANALYZED LENGTH OF FAILURE PLANE DEPTH OF TENSION CRACK HORIZONTAL DISTANCE TO UPSLOPE TENSION CRACK CALCULATED HORIZONTAL THRUST ON WALL CALCULATED EQUIVALENT FLUID PRESSURE DESIGN EQUIVALENT FLUID PRESSURE

56 130.3 1000.0 17288.1 2257 19.7 3.7 11.0 8773.4 43.9 45.0

degrees square feet pounds pounds trials feet feet feet pounds pcf pcf

THE CALCULATION INDICATES THAT THE PROPOSED CANTILEVERED RETAINING WALLS MAY BE DESIGNED FOR AN EQUIVALENT FLUID PRESSURE OF 45 POUNDS PER CUBIC FOOT.

feet degrees pounds Point degrees degrees feet feet

APPENDIX ‘E’ Grading Specifications

STANDARD GRADING SPECIFICATIONS These specifications present the usual and minimum requirements for grading operations performed under our supervision. GENERAL 1) The Geotechnical Engineer and Engineering Geologist are the developer's representative on the project. 2) All clearing, site preparation or earth work performed on the project shall be conducted by the contractor under the supervision of the Geotechnical Engineer. 3) It is the contractor's responsibility to prepare the ground surface to receive the fills to the satisfaction of the Geotechnical Engineer and to place, spread, mix, water, and compact the fill in accordance with the specifications of the Geotechnical Engineer. The contractor shall also remove all material considered unsatisfactory by the Geotechnical Engineer. 4) It is the contractor's responsibility to have suitable and sufficient compaction equipment on the job site to handle the amount of fill being placed. If necessary, excavation equipment will be shut down to permit completion of compaction. Sufficient watering apparatus will also be provided by the contractor, with due consideration for the fill material, rate of placement and time of year. 5) A final report shall be issued by our firm outlining the contractor's conformance with these specifications. SITE PREPARATION 1) All vegetation and deleterious materials such as rubbish shall be disposed of off-site. Soil, alluvium or rock materials determined by the Geotechnical Engineer as being unsuitable for placement in compacted fills shall be removed and wasted from the site. Any material incorporated as a part of a compacted fill must be approved by the Geotechnical Engineer.

Page 2 Standard Grading Specifications 2) The Engineer shall locate all houses, sheds, sewage disposal systems, large trees or structures on the site or on the grading plan to the best of his knowledge prior to preparing the ground surface. Any underground structures such as cesspools, cisterns, mining shafts, tunnels, septic tanks, wells, pipe lines, or others not located prior to grading are to be removed or treated in a manner prescribed by the Geotechnical Engineer. 3) After the ground surface to receive fill has been cleared, it shall be scarified, disced or bladed by the contractor until it is uniform and free from ruts, hollows, hummocks or other uneven features which may prevent uniform compaction. The scarified ground surface shall then be brought to optimum moisture, mixed as required, and compacted as specified. If the scarified zone is greater than twelve inches (12") in depth, the excess shall be removed and placed in lifts restricted to six inches (6"). Prior to placing fill, the ground surface to receive fill shall be inspected, tested and approved by the Geotechnical Engineer. PLACING, SPREADING AND COMPACTION OF FILL MATERIALS 1) The selected fill material shall be placed in layers which when compacted shall not exceed six inches (6") in thickness. Each layer shall be spread evenly and shall be thoroughly mixed during the spreading to insure uniformity of material and moisture of each layer. 2) Where the moisture content of the fill material is below the limits specified by the Geotechnical Engineer, water shall be added until the moisture content is as required to assure thorough bonding and thorough compaction. 3) Where the moisture content of the fill material is above the limits specified by the Geotechnical Engineer, the fill materials shall be aerated by blading or other satisfactory methods until the moisture content is adequate.


Page 3 Standard Grading Specifications COMPACTED FILLS 1) Any material imported or excavated on the property may be utilized in the fill, provided each material has been determined to be suitable by the Geotechnical Engineer. Roots, tree branches or other matter missed during clearing shall be removed from the fill as directed by the Geotechnical Engineer. 2) Rock fragments less than six inches (6") in diameter may be utilized in the fill, provided: a) They are not placed in concentrated pockets. b) There is a sufficient percentage of fine-grained material to surround the rocks. c) The distribution of the rocks is supervised by the Geotechnical Engineer. 3) Rocks greater than six inches (6") in diameter shall be taken off-site, or placed in accordance with the recommendations of the Geotechnical Engineer in areas designated as suitable for rock disposal. Details for rock disposal such as location, moisture control, percentage of rock placed, will be referred to in the "Conclusions and Recommendations" section of the geotechnical report. If the rocks greater than six inches (6") in diameter were not anticipated in the preliminary geotechnical and geology report, rock disposal recommendations may not have been made in the "Conclusions and Recommendations" section. In this case, the contractor shall notify the Geotechnical Engineer if rocks greater than six inches (6') in diameter are encountered.

The Geotechnical Engineer will than prepare a rock disposal

recommendation or request that such rocks be taken off-site. 4) Representative samples of materials to be utilized as compacted fill shall be analyzed in the laboratory by the Geotechnical Engineer to determine their physical properties. If any materials other than that previously tested is encountered during grading, the appropriate analysis of this material shall be conducted by the Geotechnical Engineer as soon as possible. Material that is spongy, subject to decay or otherwise considered unsuitable shall not be used in the compacted fill. 5) Each layer shall be compacted to ninety percent (90%) of the maximum density in compliance with the testing method specified by the controlling governmental agency (ASTM D-1557-02).


Page 4 Standard Grading Specifications If compaction to a lesser percentage is authorized by the controlling governmental agency because of a specific land use or expansive soil conditions, the area to receive fill compacted to less than ninety percent (90%) shall either be delineated on the grading plan or appropriate reference made to the area in the geotechnical report. 6) Compaction shall be by sheeps foot roller, multi-wheeled pneumatic tire roller, or other types of acceptable rollers. Rollers shall be of such design that they will be able to compact the fill to the specified density. Rolling shall be accomplished while the fill material is at the specified moisture content. The final surface of the lot areas to receive slabs-on-grade should be rolled to a smooth, firm surface. 7) Field density tests shall be made by the Geotechnical Engineer of the compaction of each layer of fill. Density tests shall be made at intervals not to exceed two feet (2') of fill height provided all layers are tested. Where the sheeps foot rollers are used, the soil may be disturbed to a depth of several inches and density readings shall be taken in the compacted material below the disturbed surface. When these readings indicate the density of any layer of fill or portion thereof is below the required ninety percent (90%) density, the particular layer or portion shall be reworked until the required density has been obtained. 8) Buildings shall not span from cut to fill. Cut areas shall be over excavated and compacted to provide a fill mat of three feet (3'). FILL SLOPES 1) All fills shall be keyed and benched through all top soil, colluvium, alluvium, or creep material into sound bedrock or firm material where the slope receiving fill exceeds a ratio of five (5) horizontal to one (1) vertical, in accordance with the recommendations of the Geotechnical Engineer. 2) The key for side hill fills shall be a minimum of fifteen feet (15') within bedrock or firm materials, unless otherwise specified in the geotechnical report. 3) Drainage terraces and subdrainage devices shall be constructed in compliance with the ordinances of the controlling governmental agency, or with the recommendations of the Geotechnical Engineer. 4) The Contractor will be required to obtain a minimum relative compaction of ninety percent (90%) out to the finish slope face of fill slopes, buttresses, and stabilization fills. This may be achieved by either over-building


Page 5 Standard Grading Specifications the slope and cutting back to the compacted core, or by direct compaction of the slope face with suitable equipment, or by any other procedure which produces the required compaction. 5) All fill slopes should be planted or protected from erosion by methods specified in the geotechnical report and by the governing agency. 6) Fill-over-cut slopes shall be properly keyed through topsoil, colluvium, or creep material into rock or firm materials. The transition zone shall be stripped of all soil prior to placing fill. CUT SLOPES 1) The Engineering Geologist shall inspect all cut slopes excavated in rock, lithified, or formation material at vertical intervals not exceeding ten feet (10'). 2) If any conditions not anticipated in the preliminary report such as perched water, seepage, lenticular or confined strata of a potentially adverse nature, unfavorably inclined bedding, joints, or fault planes, are encountered during grading, these conditions shall be analyzed by the Engineering Geologist and Geotechnical Engineer; and recommendations shall be made to treat these problems. 3) Cut slope that face in the same direction as the prevailing drainage shall be protected from slope wash by a non-erosive interceptor swale placed at the top of the slope. 4) Unless otherwise specified in the geological and geotechnical report, no cut slopes shall be excavated higher or steeper than that allowed by the ordinances of the controlling governmental agencies. 5) Drainage terraces shall be constructed in compliance with the ordinances of controlling governmental agencies, or with the recommendations of the Geotechnical Engineer or Engineering Geologist. GRADING CONTROL 1) Inspection of the fill placement shall be provided by the Geotechnical Engineer during the progress of grading. 2) In general, density tests should be made at intervals not exceeding two feet (2') of fill height or every five hundred (500) cubic yards of fill placed. These criteria will vary depending on soil conditions and the size of the job. In any event, an adequate number of field density tests shall be made to verify that the required compaction is being achieved.


Page 6 Standard Grading Specifications 3) Density tests should also be made on the surface materials to receive fill as required by the Geotechnical Engineer. 4) All clean-out, processed ground to receive fill, key excavations, subdrains, and rock disposal must be inspected and approved by the Geotechnical Engineer prior to placing any fill.

It shall be the Contractor's

responsibility to notify the Geotechnical Engineer when such areas are ready for inspection. CONSTRUCTION CONSIDERATIONS 1) Erosion control measures, when necessary, shall be provided by the Contractor during grading and prior to the completion and construction of permanent drainage controls. 2) Upon completion of grading and termination of inspections by the Geotechnical Engineer, no further filling or excavating, including that necessary for footings, foundations, large tree wells, retaining walls, or other features shall be performed without the approval of the Geotechnical Engineer or Engineering Geologist. 3) Care shall be taken by the contractor during final grading to preserve any berms, drainage terraces, interceptor swales, or other devices of a permanent nature on or adjacent to the property.


Geotechnical Report

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