CHAPTER 1
PROBLEM STATEMENT
As Malaysia’s roads become more congested, the Works Ministry has the daunting task of ensuring they are constantly in good condition and safe for motorists. Road infrastructure development is generally synonymous with the overall growth of a nation. Malaysia has had a tremendous increase in road mileage since the last 40 years, expedited by her independence. With the convenience of road development comes issues that cause specific inconvenience to the people, namely poor road condition during rainy seasons, traffic congestion and road accidents. During the rainy seasons, many areas will have potholes and other types of problems, creating a dangerous condition and causing accidents as drivers react to avoid them.
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Potholes, cracks, and other problems on roads and pavements can lead to accidents. Road pavement shall be strong, smooth, rough, economical, and complying with sanitary and hygiene requirements. These characteristics depend on the type and structure of pavement, traffic volumes and driving speed, road significance as well as materials used for road construction. The most important characteristics of pavement are its strength, smoothness and roughness. When pavement is not strong enough, rutting or even breaching occurs, and rolling resistance increases considerably. Therefore, it is extremely important to design such road pavement structure, which complies with the imposed requirements.
Successful chip seal construction depends on a combination of rational science and qualitative judgment in the field. Success is usually measured by a lack of customer complaints that sometimes occur when loose aggregate chips come in contact with windshields at high speed. Allowing traffic on a fresh chip seal too soon can result in windshield damage if the asphalt binder lacks sufficient strength to resist dislodgement. Therefore, timing the removal of traffic control is a key element in the success of any chip seal project. A desirable addition to the technology would be a quantitative process that identifies when a chip seal is ready for uncontrolled traffic.
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In order to complete our project for BFC 3042, we are required to conduct a survey on pavement condition to identify the damage which occurred and propose a suitable pavement method work to local authority.
1.1
SCOPE
For this task we are required to conduct a survey on the pavement condition in the certain road, along 1kilometer. We have to do a few methods to complete this survey. We had picked up the main road from Parit Jelutong. At the site survey, we have to determine some categories of pavement distress and damage. From the data obtained, we have to discuss and analyze the suitable method to regarding the condition.
1.2
AIM
We had survey a few roads in the radius of UTHM. We found that Parit Jelutong is most suitable site that we chose to continue the project as it is nearby to UTHM. The respective road had a few sort of damaged that easily can found on their pavement due to transportation of oil palm material in and out from the particular place.
1.3
METHOD
For the method of analyzation, we collect the data by filling the damage found into the condition survey data sheet. We also did the sand patch method in order to covers the determination of the average texture depth of paved surface sand to give the volume of voids. For the treatment, we use chip seal to assure that the damage occurred has been treat and the road will be use safe and smoothly.
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CHAPTER 2
LITERATURE REVIEW
The movement of people and goods throughout the world is primarily dependent upon a transportation network consisting of roadways. Most, if not all, business economies, personal economies, and public economies are the result of this transportation system. Considering the high initial and annual cost of roadways and since each roadway serves many users, the only prudent owner of roadways is the public sector. Thus it is the discipline of civil engineering that manages the vast network of roadways. The surface of these roadways, the pavement, must have sufficient smoothness to allow a reasonable speed of travel, as well as ensure the safety of people and cargo. Additionally, once the pavement is in service, the economies that depend upon it will be financially burdened if the pavement is taken out of service for repair or maintenance. Thus, pavements should be designed to be long lasting with few maintenance needs.
The accomplishment of a successful pavement design depends upon several variables. The practice of pavement design is based on both engineering principles and experience. Pavements were built long before computers, calculators, and even slide rules. Prior to more modern times, pavements were designed by trial-and-error and commonsense methods, rather
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than the more complicated methods being used currently. Even more modern methods require a certain amount of experience and common sense. The most widely used methods today are based on experiments with full-scale, in-service pavements that were built and monitored to failure. Empirical information derived from these road tests is the most common basis for current pavement design methods. More recently, with the ever-expanding power of personal computers, more mathematically based pavement design methods such as finite element analysis and refined elastic layer theory have been introduced. These methods require extensive training to use and are not developed for the inexperienced. Types of pavements can be broadly categorized as rigid, flexible, or composite. The characteristics of these types are reviewed in the following articles.
RIGID PAVEMENT FLEXIBLE PAVEMENT COMPOSITE PAVEMENT (OVERLAYS)
In this literature review, we need to spend and focus over the aspect that involving in pavement design criteria. It is centralized as three of analytical important prospect in this part of literature review for the Project gaining information as listed below; PAVEMENT STRESS DESIGN OF CHIP SEAL TYPES OF PAVEMENT DISTRESS
Rigid pavement can be constructed with contraction joints, expansion joints, dowelled joints, no joints, temperature steel, continuous reinforcing steel, or no steel. Most generally, the construction requirements concerning these options are carefully chosen by the owner or the public entity that will be responsible for future maintenance of the pavement. The types of joints and the amount of steel used are chosen in concert as a strategy to control cracking in the concrete pavement. Often, the owner specifies the construction requirements but requires the designer to take care of other details such as intersection jointing details and the like. It is
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imperative that a designer understand all of these design options and the role each of these plays in concrete pavement performance.
Load transfer is the critical element at joints and cracks. In undo welled, unreinforced pavements, any load transfer must be provided by aggregate interlock.
Source: Highway Engineering Handbook, 2nd edition
Aggregate interlock is lost when slabs contract and the joints or cracks open up. Also, interlock is slowly destroyed by the movement of the concrete as traffic passes over. Given large temperature variations and heavy trucks, aggregate interlock is ineffectual, and faulting is the primary result.
Where a long joint spacing is used and intermediate cracks are expected, steel reinforcement is added to hold the cracks tightly closed (JRCP). This allows the load transfer to be accomplished through aggregate interlock without the associated problems described above. Contraction joints do not provide for expansion of the pavement unless the same amount of contraction has already taken place. This contraction will initially be from shrinkage due to concrete curing. Later changes in the pavement length are due to temperature changes. Where
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fixed objects such as structures are placed in the pavement, the use of an expansion joint is warranted. Expansion joints should be used sparingly. The pavement will be allowed to creep toward the expansion joint, thus opening the adjacent contraction joints. This can cause movement in the adjacent contraction joints in excess of their design capabilities and result in premature failures.
This is showed, how the good implementation and idea given to review the overall literature of Project Making Process with high intention of other fundamental idea in highway engineering.
2.1
PAVEMENT STRESS
Pavement Stress is considered to be under the flexible pavement. The basic idea of pavement stress starting from the loading area and impact on the pavement. Rutting in asphalt pavement includes densification and shear flow of hot-mix asphalt, but the majority of severe instable rutting results from shear flow within the asphalt mixtures. In recent years, another type of surface distress called Top-Down Cracking (TDC), which is usually found in longitudinal path, has become more common in asphalt pavement, this is also considered as a shear-related failure. As a result, shear stress is believed to be one of the critical factors affecting pavements performance, and it is necessary to well understand shear stress in asphalt pavements. To gain an accurate understanding of the effect of shear stress on pavement performance, a laboratory method of applying tirepavement contact pressure is employed in this paper. The results are compared for differing loading conditions. The effects of tire pressure and stress components in terms of vertical and horizontal stress on shear stress are comprehensively investigated by three-dimensional finite element method. In addition, the effects of asphalt layer thickness and interface conditions are also discussed.
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Car loading is the most important aspect in order to effect the load distribution on pavement surface to the base. Rutting influenced by the load of car, and regularly happened on the mid of section in single road. We need to predict and understand stress - strain distribution within the pavement structure as they relate to failure cracking and rutting.
In Flexible Pavement Stress Analysis, there are two (2) types of prediction stress in pavement that occur. 1. Numerical Models 2. Ideal Models
Numerical Models Need model to compute deflections (δ) and strains (ε). Numerous models available with different: –Capabilities – Underlying assumptions – Complexity – Material information requirements Ideal Models Predicts and Input Parameters • Stresses • Strains -
Static & dynamic loads
-
Material properties
-
Traffic
-
Environment
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Available Models in these fields of highway analysis that use widely in real site as below listed; o Multilayer Elastic Theory o Finite Element Methods o
Viscoelastic Theory (time and temp.-dependent behavior)
o
Dynamic Analysis (inertial effects)
o
Thermal Models (temperature change)
But most widely used is; o
Reasonable Results
o Properties Relatively Simple to Obtain
Falling Weight Deflectometer
Use elastic theory to predict the deflection basin for the given load. Then iterate with different module configurations until the calculated deflection basin matches the measured. This Process using the tools; • Small trailer • Dropping Weight • Geophones • Deflection Basin
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This Pavement Stress generated by the theory of Multilayer Elastic Theory. And a few assumptions were taking part of the analysis to make sure that will be reasonable and practice to be done. As result, a graph generate by the findings in the analysis as theory assumption had made before the analysis. The figure of finding as showed below.
Figure Generating Finding from Analysis Theory Source: Dr. Christos Drakos, University of Florida
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Graph: One-layer Solutions (Foster & Ahlvin 1954) Shear stresses due to circular loading. Source: Dr. Christos Drakos, University of Florida
Asphalt concrete pavement, also referred to as flexible pavement, is a mixture of sand, aggregate, a filler material, and asphalt cement combined in a controlled process, placed, and compacted. The filler material can range from quarry crushing dust and asphalt-plant bag house fines to wood fibers (cellulose). There are many additives that can be used in asphalt concrete mixes to encourage thicker cement coatings, more elastic mixes, stiffer mixes, and less temperature-sensitive mixes. Flexible pavements can be of a type constructed on a prepared sub grade, which is called full-depth asphalt concrete pavement (FDACP), or of a type built on an untreated granular base, which is not as carefully identified by the industry but is referred to herein as deep-strength asphalt concrete pavement (DSACP).
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2.2
DESIGN OF CHIP SEAL
There are a few questions about the Chip Seal that play around the fields of construction especially among the people who lively involved in the industry of road maintenance. To clarify the questions issue that emerged in terms of right knowledge and fundamental of Chip Seal, the Maintenance Technical Advisory Guide (MTAG) US, were using to keep maintain and briefly explain the Chip Seal Design.
2.3
MAINTENANCE TECHNICAL ADVISORY GUIDE (MTAG)
2.3.1 Chip Seal from MTAG Review.
Application of asphalt binder on existing pavement followed by a layer of aggregate chips. The treatment is then rolled to embed the aggregate into the binder.
o Performance •Typical treatment life: 5 to 10 years •Function of climate, existing pavement condition, traffic, type of chip seal o Average cost •$2.50 to $5.00/yd2 (depending on oil price)
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The chip seal practice were doing and apply base on where and when the necessary work were implementing to solve the road maintenance problem base on the criteria that listed below to make sure the capability and workability of work in high intensity of enduring quality of pavement for the live years. o Surface for light to medium traffic (ADT < 30,000) o Waterproof layer o Skid resistant surface o Seal the surface o Address bleeding o Temporary base course cover o Define shoulders
Picture: Chip Seal Process
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After we defined the necessarily when and where, we have to know that the chip seal also have some condition that not related to the main aspect. So, we have to consider the right time when we are not going to use the Chip Seal as condition prefer below; o Structurally deficient pavements o Cracks >1/4 in width unless sealed o Large number of potholes o Rutting >1/2 in o Ride quality needs significant improvement
In order to the step of success in chip seal design, the right key of chip seal design we have to consider so that the work going to be success and done properly. o Proper surface preparation o Use the right binder and clean aggregates o Follow the construction specs, including the need for traffic control o Chip seal in good weather conditions
Picture: Criteria Design Step and Process
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2.3.2 Chip Seal Variations o Applications o Single chip seals o Double or triple chip seals o Cape seals o Fabric and chip seals o Scrub seals o Asphalt Binder Types o PME o PMA o AR
(Single Chip Seals)
(Double Chip Seals)
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(Cape Seals)
(Fabric and Chip Seals)
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(Fabric and Chip Seals)
2.3.3 Design, Materials & Specifications
Determine Quantity o Residual asphalt content o Asphalt cement factor = 1.0 o Emulsion factors range = 0.65 to 0.70 o Aggregate application rate o Single chip layer o No more than 10% excess chips o 70% embedment recommended
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Chip Seal Design Methods
McLeod procedure
Asphalt Institute method
1. Determine aggregate size and specific gravity 2. Aggregate and binder quantities from table 3. Adjust aggregate (if necessary) 4. Adjust asphalt content based on condition of road (if necessary) Material Selection –Binder -
Polymer-modified emulsions Polymer-modified binder Polymer-modified rejuvenating emulsions (PMRE) Asphalt Rubber
Material Selection-Emulsion Ingredients -
Asphalt Water Emulsifying agent (surfactant)
2.3.4 Asphalt Rubber Chip Seals Binder Material Field Blended (min. 45 minutes and viscosity 1,500 cps-4,000) hot asphalt, extender oil, crumb rubber, and high natural.AR binder application is usually .60 gal / square yard through an agitated distributor truck attached with a vapor recovery system. Aggregate Chips are always hot pre-coated, and applied at 35-40 lbs. per square yard.
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Source: Maintenance Technical Advisory Guide (MTAG)-U.S
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2.4
TYPES OF FLEXIBLE PAVEMENT DISTRESS
Index of Pavement Distresses Shown on this Page
Fatigue (alligator) cracking Bleeding Block cracking Corrugation and shoving Depression Joint reflection cracking Lane/shoulder drop-off Longitudinal cracking Patching
2.4.1
Polished aggregate Potholes Raveling Rutting Slippage cracking Stripping Transverse (thermal) cracking Water bleeding and pumping
Fatigue (Alligator) Cracking This section is a summary of the major flexible pavement distresses. Each distress discussion includes (1) pictures if available, (2) a description of the distress, (3) why the distress is a problem and (4) typical causes of the distress.
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Description Series of interconnected cracks caused by fatigue failure of the HMA surface (or stabilized base) under repeated traffic loading. In thin pavements, cracking initiates at the bottom of the HMA layer where the tensile stress is the highest then propagates to the surface as one or more longitudinal cracks. This is commonly referred to as "bottom-up" or "classical" fatigue cracking. In thick pavements, the cracks most likely initiate from the top in areas of high localized tensile stresses resulting from tire-pavement interaction and asphalt binder aging (top-down cracking). After repeated loading, the longitudinal cracks connect forming many-sided sharp-angled pieces that develop into a pattern resembling the back of an alligator or crocodile. Problem Indicator of structural failure, cracks allow moisture infiltration, roughness, may further deteriorate to a pothole Possible Causes Inadequate structural support, which can be caused by a myriad of things. A few of the more common ones are listed here:
Decrease in pavement load supporting characteristics o
Loss of base, sub base or sub grade support (e.g., poor drainage or spring thaw resulting in a less stiff base).
o
Stripping on the bottom of the HMA layer (the stripped portion contributes little to pavement strength so the effective HMA thickness decreases)
o
Increase in loading (e.g., more or heavier loads than anticipated in design)
o
Inadequate structural design
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o
Poor construction (e.g., inadequate compaction)
Repair A fatigue cracked pavement should be investigated to determine the root cause of failure. Any investigation should involve digging a pit or coring the pavement to determine the pavement's structural makeup as well as determining whether or not subsurface moisture is a contributing factor. Once the characteristic alligator pattern is apparent, repair by crack sealing is generally ineffective. Fatigue crack repair generally falls into one of two categories: o
Small, localized fatigue cracking indicative of a loss of subgrade support. Remove the cracked pavement area then dig out and replace the area of poor subgrade and improve the drainage of that area if necessary. Patch over the repaired subgrade.
o
Large fatigue cracked areas indicative of general structural failure. Place an HMA overlay over the entire pavement surface. This overlay must be strong enough structurally to carry the anticipated loading because the underlying fatigue cracked pavement most likely contributes little or no strength (Roberts et. al., 1996).
2.4.2
Bleeding
Description A film of asphalt binder on the pavement surface. It usually creates a shiny, glass-like reflecting surface (as in the third photo) that can become quite sticky. Problem Loss of skid resistance when wet
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Possible Causes Bleeding occurs when asphalt binder fills the aggregate voids during hot weather and then expands onto the pavement surface. Since bleeding is not reversible during cold weather, asphalt binder will accumulate on the pavement surface over time. This can be caused by one or a combination of the following:
Excessive asphalt binder in the HMA (either due to mix design or manufacturing)
Excessive application of asphalt binder during BST application (as in the above figures)
Low HMA air void content (e.g., not enough room for the asphalt to expand into during hot weather)
Repair The following repair measures may eliminate or reduce the asphalt binder film on the pavement's surface but may not correct the underlying problem that caused the bleeding:
Minor bleeding can often be corrected by applying coarse sand to blot up the excess asphalt binder.
Major bleeding can be corrected by cutting off excess asphalt with a motor grader or removing it with a heater planer. If the resulting surface is excessively rough, resurfacing may be necessary (APAI, no date given).
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2.4.3
Block Cracking
Description Interconnected cracks that divide the pavement up into rectangular pieces. Blocks range in size from approximately 0.1 m2 (1 ft2) to 9 m2 (100 ft2). Larger blocks are generally classified as longitudinal and transverse cracking. Block cracking normally occurs over a large portion of pavement area but sometimes will occur only in non-traffic areas. Problem Allows moisture infiltration, roughness Possible Causes HMA shrinkage and daily temperature cycling. Typically caused by an inability of asphalt binder to expand and contract with temperature cycles because of:
Asphalt binder aging
Poor choice of asphalt binder in the mix design
Repair Strategies depend upon the severity and extent of the block cracking:
Low severity cracks (< 1/2 inch wide). Crack seal to prevent (1) entry of moisture into the sub grade through the cracks and (2) further raveling of the crack edges. HMA can provide years of satisfactory service after developing small cracks if they are kept sealed (Roberts et. al., 1996).
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High severity cracks (> 1/2 inch wide and cracks with raveled edges). Remove and replace the cracked pavement layer with an overlay
2.4.4
Corrugation and Shoving
Description A form of plastic movement typified by ripples (corrugation) or an abrupt wave (shoving) across the pavement surface. The distortion is perpendicular to the traffic direction. Usually occurs at points where traffic starts and stops (corrugation) or areas where HMA abuts a rigid object (shoving). Problem Roughness Possible Causes Usually caused by traffic action (starting and stopping) combined with:
An unstable (i.e. low stiffness) HMA layer (caused by mix contamination, poor mix design, poor HMA manufacturing, or lack of aeration of liquid asphalt emulsions)
Excessive moisture in the sub grade
Repair A heavily corrugated or shoved pavement should be investigated to determine the root cause of failure. Repair strategies generally fall into one of two categories:
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Small, localized areas of corrugation or shoving. Remove the distorted pavement and patch.
Large corrugated or shoved areas indicative of general HMA failure. Remove the damaged pavement and overlay.
2.4.5
Depression
Description Localized pavement surface areas with slightly lower elevations than the surrounding pavement. Depressions are very noticeable after a rain when they fill with water. Problem Roughness, depressions filled with substantial water can cause vehicle hydroplaning Possible Causes Frost heave or sub grade settlement resulting from inadequate compaction during construction. Repair By definition, depressions are small localized areas. A pavement depression should be investigated to determine the root cause of failure (i.e., sub grade settlement or frost heave). Depressions should be repaired by removing the affected pavement then digging out and replacing the area of poor sub grade. Patch over the repaired sub grade.
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2.4.6
Joint Reflection Cracking
Description Cracks in a flexible overlay of a rigid pavement. The cracks occur directly over the underlying rigid pavement joints. Joint reflection cracking does not include reflection cracks that occur away from an underlying joint or from any other type of base (e.g., cement or lime stabilized). Problem Allows moisture infiltration, roughness Possible Causes Movement of the PCC slab beneath the HMA surface because of thermal and moisture changes. Generally not load initiated, however loading can hasten deterioration. Repair Strategies depend upon the severity and extent of the cracking:
Low severity cracks (< 1/2 inch wide and infrequent cracks). Crack seal to prevent (1) entry of moisture into the sub grade through the cracks and (2) further raveling of the crack edges. In general, rigid pavement joints will eventually reflect through an HMA overlay without proper surface preparation.
High severity cracks (> 1/2 inch wide and numerous cracks). Remove and replace the cracked pavement layer with an overlay.
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2.4.7
Raveling
Description The progressive disintegration of an HMA layer from the surface downward as a result of the dislodgement of aggregate particles. Problem Loose debris on the pavement, roughness, water collecting in the raveled locations resulting in vehicle hydroplaning, loss of skid resistance.
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Possible Causes Several including:
Loss of bond between aggregate particles and the asphalt binder as a result of:-
o
A dust coating on the aggregate particles that forces the asphalt binder to bond with the dust rather than the aggregate
o
Aggregate Segregation. If fine particles are missing from the aggregate matrix, then the asphalt binder is only able to bind the remaining coarse particles at their relatively few contact points.
o
Inadequate compaction during construction. High density is required to develop sufficient cohesion within the HMA. The third figure above shows a road suffering from raveling due to inadequate compaction caused by cold weather paving.
Mechanical dislodging by certain types of traffic (studded tires, snowplow blades or tracked vehicles). The first and fourth figures above show raveling most likely caused by snow plows.
Repair A raveled pavement should be investigated to determine the root cause of failure. Repair strategies generally fall into one of two categories:
Small, localized areas of raveling. Remove the raveled pavement and patch.
Large raveled areas indicative of general HMA failure. Remove the damaged pavement and overlay.
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CHAPTER 3
METHODOLOGY
3.1
FORMING GROUP
In week 1, lecturer told us there is a project for Highway Engineering subject and she asked us to form in a group. Each group consists of 5 people but special permission to our group where we contain of 6 students.
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3.2
PROBLEM AND SCOPE OF PROJECT
In week 3, lecturer gave us the problem and the scope of project. She briefly explained the problem. The problem was about the roads that have been built are often damaged due to vehicle load and environment. This situation requires the maintenance work to be done so that it can provide comfortable riding to road users. Each of the group has to conduct a survey of pavement conditions to determine damages and recommend appropriate pavement preservation work to local authorities. The local authority would like to use chip seal method to repair the damaged road surface. Subsequently, students have to design an appropriate chip seal treatment. The factors of the damage to the roads also need to be reviewed, studied and related design aspects of the existing drainage system.
3.3
BRIEFING OR BRAINSTORMING SESSION
Our lecturer gave us a brainstorming on how to solve the related problem. In this session, lecturer had given us some opinions such as the procedures and the requirements of the project and the equipments that are needed for this project
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3.4
DISCUSSION / INVESTIGATING PROBLEM
After the lecturer briefed us the project problem and the group discussion on 26 July 2010, we had suggested few sites for our project which are Parit Jelutong, Jalan Rengit, Taman Melewar road and Parit Haji Rais. To determine the site for our project, we have to conduct a survey on the site so that the site that we choose is fulfilled the requirements of this project such as minimum four cracks within 1km of the road. We decided to choose Parit Jelutong as our project site after we conducted surveys on these few sites on 30 July 2010. Before we start the onsite laboratory works, we were divided into several small groups. Each of the group member has to identify the problems and do research on the problems in the internet, books and journal. After that, the identified problems will be solved in FILA table by using brainstorming method. The method of FILA table is as followings:
FACTS - the roads that have been built are often damaged due to vehicle load and environment
IDEAS
LEARNING ISSUES
-Single chip seal
-Types of chip seal
-Double chip seal
-Design of chip seal
-Stress absorbing Membrane (SAM)
-Aggregate for chip seals
-Membrane Interlayer (SAMI)
ACTION PLANS - Identified the cracks - Based on data analysis, recommend a design of chip seal to repair the cracks
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3.5
ONSITE LABORATORY WORKS
We did our onsite laboratory works on 2 August 2010. First, we measured 1km for the length and the width of the road. At the same time, we counted the traffic volume for the non-peak hour. Subsequently, we did the sand patch for 4 times at the distance of 250m each. The sand patch procedures are as following: 1. Ensure the pavement surface is clear of debris by sweeping the surface with a small brush. Test area is to be clear of cracking and the pavement area must be dry. 2. A known volume of sand, is measured and then poured onto the road surface to form a cone, using the measuring cylinder. 3. Spread the sand with the spreading disc to form a circular patch. Apply horizontal forces to the spreading tool and work outwards in a circular pattern until the surface depressions are filled to the level of the peaks. Sand is to be used only once. 4. Measure the diameter at four different angles, rotating 45° between each measurement.
After we had done the sand patch, we identified the types of cracks, measure the length, width and depth (pothole) and filled the data in the lab sheet. Consequently, we counted the traffic volume again for the peak hour and non peak hour from 11pm -2pm and 4pm-7pm.
3.6
LABORATORY WORKS
After we did the onsite laboratory works, we did the Flakiness and Elongation index laboratory to determine the size of the chip seal to be used.
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3.7
RESULT ANALYSIS AND RECOMMENDATION
Based on the data that got from on-site laboratory works and laboratory works, firstly we have to get the Pavement Condition Index (PCI) value. To obtain PCI value, there are steps which are Distress Density, Corrected Deduct Value and PCI Rating scale. The PCI value for section 1, 2, 3 and 4 are 54 (LOS D, POOR), 83 (LOS B, SATISFACTORY), 81 (LOS B, SATISFACTORY) and 82 (LOS B, SATISFACTORY) respectively. The total PCI value for 1km road is 75 (LOS B, SATISFACTORY) which means section pavement is in satisfactory condition, Level of Service is B and needed to preventive maintenance. Based on the total PCI value for 1 km length of the road, we design the chip seal design. According to our chip seal design, we recommend that the road shall be using Double Chip Seal, the size for first layer is 14mm and the size for second layer is 6mm.
3.8
FINAL REPORT AND PRESENTATION
We submitted our final report and presented our project on week 12. On Saturday 16th October there will be a poster presentation will be carried out as part of our evaluation.
3.9
FINAL EVALUATION
Final evaluation on our group will be given after we submitted our final report and did our presentation based on quality of our report and presentation and the way that we presented.
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CHAPTER 4
DATA ANALYSIS AND DISCUSSION
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BRANCH : TRAFFIC LABORATORY UTHM
DATE : 9 AUGUST 2010
SURVEYED BY:
SAMPLE UNIT :
MOGANRAJ
SECTION : 4 (1 km)
SAMPLE AREA : 4.8m x 250m
11. Patching & 01. Aligator Cracking (m2)
02. Bleeding (m2)
06. Depression (m2)
Utility Cut
07. Edge Cracking
Patching (m2)
17. Slippage Cracking (m2)
(m) 12. Polished 08. Joint Reflection
03. Block Cracking (m2)
Aggregate (m2)
Cracking (m)
18. Swell (m2) 13. Potholes(no)
04. Bumps and Sags (m)
19. Weathering/ 14. Railroad Crossing
05. Corrugation (m2)
09. Lane/shoulder
(m)
Ravelling (m2)
Drop (m)
10. Longitudinal &
15. Rutting (m2)
16. Shoving (m2)
Transverse Cracking (m)
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Sample 1 (for section 0 – 250m) Determine the Distress Density and Deduct Value DISTRESS
QUANTITY
SURVEY
TOTAL
DENSITY (%)
DEDUCT VALUE
100*(3.7/1200) 01M
3.7
3.7
14 = 0.31 100*(5.6/1200)
10M
5.6
5.6
6 = 0.47 100*(0.4/1200)
13L
0.4
0.4
42 = 0.03
Maximum allowable number of deducts, m Highest deduct value, HDV = 42 m = 1 + (9/98)(100 – HDV) = 1 + (9/98)(100 – 42) = 6.33
Deducts values in descending order = 42, 14, 6 Number of deduct value = 3
Maximum Corrected Deduct Value, CDV Number of deduct value greater than 2, q = 3 Total deduct value = 42 + 14 + 6 = 62 From Figure B – 45, CDV = 40
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NO
DEDUCT VALUES
TOTAL
q
CDV
1
42
14
6
62
3
40
2
42
14
2
58
2
43
3
42
2
2
46
1
46
Maximum CDV = 46
Determine the Pavement Condition Index, PCI
PCI
= 100 - CDVmax = 100 - 46 = 54 (LOS D, POOR)
The PCI is 54. Based on the rating for PCI value of 54, this section pavement is in poor condition, Level of Service is D and needed to major rehabilitation or deferred action.
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Sample 2 (for section 250 – 500m) Determine the Distress Density and Deduct Value DISTRESS
QUANTITY
SURVEY
TOTAL
DENSITY (%)
DEDUCT VALUE
100*(11.3/1200) 10M
11.3
11.3
9 = 0.94 100*(0.3/1200)
13M
0.3
0.3
15 = 0.03
Maximum allowable number of deducts, m
Highest deduct value, HDV = 15 m = 1 + (9/98)(100 – HDV) = 1 + (9/98)(100 – 15) = 8.82
Deducts values in descending order = 15, 9 Number of deduct value = 2
Maximum Corrected Deduct Value, CDV Number of deduct value greater than 2, q = 2 Total deduct value = 15 + 9 = 24 From Figure B – 45, CDV = 17
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NO
DEDUCT VALUES
TOTAL
q
CDV
1
15
9
24
2
17
2
15
2
17
1
17
Maximum CDV = 17
Determine the Pavement Condition Index, PCI
PCI
= 100 - CDVmax = 100 - 17 = 83 (LOS B, SATISFACTORY)
The PCI is 83. Based on the rating for PCI value of 83, this section pavement is in satisfactory condition, Level of Service is B and needed to preventive maintenance
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Sample 3 (for section 500 – 750m) Determine the Distress Density and Deduct Value
DISTRESS
QUANTITY
SURVEY
TOTAL
DENSITY (%)
DEDUCT VALUE
100*(3.6/1200) 10M
3.6
3.6
3 = 0.30 100*(0.4/1200)
13L
0.4
0.4
9 = 0.03 100*(0.3/1200)
13M
0.3
0.3
15 = 0.03
Maximum allowable number of deducts, m Highest deduct value, HDV = 15 m = 1 + (9/98)(100 – HDV) = 1 + (9/98)(100 – 15) = 8.82
Deducts values in descending order = 15, 9, 3 Number of deduct value = 3
Maximum Corrected Deduct Value, CDV Number of deduct value greater than 2, q = 3 Total deduct value = 15 + 9 + 3 = 27 From Figure B – 45, CDV = 15
41
NO
DEDUCT VALUES
TOTAL
q
CDV
1
15
9
3
27
3
15
2
15
9
2
26
2
19
3
15
2
2
19
1
19
Maximum CDV = 19
Determine the Pavement Condition Index, PCI
PCI
= 100 - CDVmax = 100 - 19 = 81 (LOS B, SATISFACTORY)
The PCI is 81. Based on the rating for PCI value of 81, this section pavement is in satisfactory condition, Level of Service is B and needed to preventive maintenance.
42
Sample 4 (for section 750 – 1000m) Determine the Distress Density and Deduct Value DISTRESS
QUANTITY
SURVEY
TOTAL
DENSITY (%)
DEDUCT VALUE
100*(1.3/1200) 01M
0.2
1.1
1.3
8 = 0.11 100*(0/3/1200)
13M
0.3
0.3
15 = 0.03
Maximum allowable number of deducts, m
Highest deduct value, HDV = 15 m = 1 + (9/98)(100 – HDV) = 1 + (9/98)(100 – 15) = 8.82
Deducts values in descending order = 15, 8 Number of deduct value = 2
Maximum Corrected Deduct Value, CDV Number of deduct value greater than 2, q = 2 Total deduct value = 15 + 8 = 23 From Figure B – 45, CDV = 16
43
NO
DEDUCT VALUES
TOTAL
q
CDV
1
15
8
23
2
16
2
15
2
17
1
18
Maximum CDV = 18
Determine the Pavement Condition Index, PCI
PCI
= 100 - CDVmax = 100 - 18 = 82 (LOS B, SATISFACTORY)
The PCI is 82. Based on the rating for PCI value of 82, this section pavement is in satisfactory condition, Level of Service is B and needed to preventive maintenance.
44
Calculation of the PCI section Jalan Parit Jelutong
PCIS
=
∑PCIri x Ari ∑Ari Where,
PCIS
PCIS
=
PCI of pavement section.
Ari
=
Area of the random sample unit i.
= (54 + 83 + 81 + 82)(1200) 4800
=
75 (LOS B, SATISFACTORY)
The PCI is 75. Based on the rating for PCI value of 75, this section pavement is in satisfactory condition, Level of Service is B and needed to preventive maintenance.
45
4.2
CHIP SEAL
Criteria of chip seal
Existing Surface and traffic
Nominal size (mm)
Soft surface, such as Penetration Macadam with < 1000 vehicle per
20mm
day Soft surface with > 1000 vehicle per day
14mm
Medium surface, such as rolled asphalt with < 1000 vehicle per day
10mm
Hard surface, such as Portland Cement Concrete or Asphalt Concrete
6mm
> 1000 vehicle per day Table Single Chip Selection Criteria
Existing Surface and traffic
Nominal size 1st + 2nd seal (mm)
Soft to medium surface with < 1000 vehicle per day
20 + 10
Hard surface with > 1000 vehicle per day
14 + 6
Table Double Chip Selection Criteria
Data gained from observation of total vehicles use the road, it is defined that total vehicles use the road in a day are :
Traffic in lane volume per hour
=
62 vph/hour/lane
Traffic in lane (vpd/lane)
=
1488 vpd/day/lane
46
Design of Chip Seal For Jalan Parit Jelutong
Proposed of Double chip seal for preventive maintenance at Jalan Parit Jelutong, Parit Raja, Batu Pahat Johor.
DETERMINATION OF SIZE, SHAPE AND GRADING OF SEALING CHIPS
Class No. Thickness Tally (a) Range Stones In mm Class
Total tally (c)
Cum. Tally (d)
Cum percent (e)
(a) x (c) (f)
(b) 1
<1
0
2
1-2
1.5
4
4
4
8
3
2-3
2.5
4
8
8
12
4
3-4
3.5
5
13
13
20
5
4-5
4.5
5
18
18
25
6
5-6
5.5
10
28
28
60
7
6-7
6.5
13
41
41
91
8
7-8
7.5
14
55
55
112
9
8-9
8.5
13
68
68
117
10
9 - 10
9.5
13
80
80
120
11
10 - 11
10.5
13
92
92
132
12
11 - 12
11.5
8
100
100
96
13
12 - 13
12.5
14
13 - 14
13.5
47
15
14 - 15
14.5
16
15 - 16
15.5
17
16 - 17
16.5
18
17 - 18
17.5
19
18 - 19
18.5
20
19 - 20
19.5
21
20 - 21
20.5
22
21 - 22
21.5
23
22 - 23
22.5
24
23 - 24
23.5
25
24 - 25
24.5
(c) =
100
(f) =
793
For 6mm: Aggregate Average Least Dimension, ALD:
ALD6mm
=
[ (f) / (c) – 0.5 ]
=
[ 793 / 100 – 0.5 ]
=
7.97 mm
For 14mm:
48
Class No. Thickness Tally (a) Range Stones In mm Class
Total tally (c)
Cum. Tally (d)
Cum percent (e)
(a) x (c) (f)
(b) 1
<1
0
2
1-2
1.5
3
2-3
2.5
4
3-4
3.5
5
4-5
4.5
6
5-6
5.5
1
1
1
6
7
6-7
6.5
3
4
4
21
8
7-8
7.5
6
10
10
48
9
8-9
8.5
12
22
22
108
10
9 - 10
9.5
10
32
32
100
11
10 - 11
10.5
13
45
45
143
12
11 - 12
11.5
10
55
55
120
13
12 - 13
12.5
12
67
67
156
14
13 - 14
13.5
10
77
77
140
15
14 - 15
14.5
7
84
84
105
16
15 - 16
15.5
6
90
90
96
17
16 - 17
16.5
4
94
94
68
18
17 - 18
17.5
4
98
98
72
19
18 - 19
18.5
2
100
100
38
20
19 - 20
19.5
21
20 - 21
20.5
49
22
21 - 22
21.5
23
22 - 23
22.5
24
23 - 24
23.5
25
24 - 25
24.5
(c) =
100
(f) =
1221
Aggregate Average Least Dimension, ALD:
ALD14mm
=
[ (f) / (c) – 0.5 ]
=
[ 1221 / 100 – 0.5 ]
=
12.27 mm
Binder Rate of Application, R
R
= ( 0.138 x ALD + e ) x Tf
Where : ALD : Average Least Dimension (mm) e
: Bitumen needed to fill road surface
Tf
: Factor to allow an increased application rate for low traffic volume to delay Durability failure
For 6 mm: R
= [ ( 0.138 x 7.97 ) + 0.004 ] x 1.0021 = 1.106 l/m2
50
For 14 mm: R
= [ ( 0.138 x 12.27 ) + 0.004 ] x 1.0021 = 1.701 l/m2
Aggregate, C
C
= 1.364 x ALD
Where : C
=
ALD =
Cover Aggregate (kg/m2) Aggregate Average Least Dimension (mm)
For 6 mm: C
= 1.364 x ALD = 1.364 x 7.97 = 10.87 kg/m2
For 14 mm: C
= 1.364 x ALD = 1.364 x 12.27 = 16.74 kg/m2
51
4.3 SAND PATCH DATA
Volume = 45 ml Ø = 2.5 cm h Height = 9.30 cm
Point
Diameter 1
Diameter 2
Diameter 3
Diameter 4
Diameter 5
Diameter 6
Average
510
510
480
500
510
480
498.33
490
450
470
480
460
470
470.00
450
450
450
460
450
440
450.00
510
540
510
540
530
530
526.67
(mm)
1
2
3
4
Average Diameter
=
498.33 + 470 + 450 + 526.67 4
=
486.25 mm
52
The texture depth, T
T
=
4V D2
Where : V = Volume (ml) D = Diameter (mm)
T
=
4V D2
=
4(45) (486.25)2
=
4.4
-
2.42 x 10-4 mm
COST RATE ESTIMATION
Proposed of Double layer chip Seal for preventive maintenance at Jalan Parit Jelutong, Parit Raja, Batu Pahat, Johor Darul Ta’zim.
-
For 4800 m2 area of chip seal will bring two (2) days work.
First layer Supply and Lay Modified Bitumen or Equivalent for the Chip Seal Layer o For bitumen application rate of 1.10 litres /sq .m to 1.30 litres/sq.
53
Machinery Descriptions
Rate per day (RM)
Quantity
Days
Total (RM)
20Tonne Dump Truck
570
1
2
1140
TOTAL
1140
Manpower Descriptions
Rate per day (RM)
Quantity
Days
Total (RM)
General Labour
50
2
2
200
Driver
65
2
2
260
TOTAL
460
Raw Materials (Bitumen) 1.10 litres /sq .m to 1.30 litres/sq (Average 1.2 litres/sq.m)
Description
Rate per barrel (RM)
Bitumen
Quantit y
Total
29
14500
RM 500 TOTAL
14500
NOTE :
1 Barrel = 200 litres
4800 m2 x 1.2litres/m2 = 5760 litres
(5760 litres / 200 litres) = 28.8 » 29 barrels
4800 m2 need 29 barrels bitumen for first layer.
54
COST for 4800m2 ITEM
COST (RM)
Machinery
1 140
Manpower
460
Materials
14 500
Cost
16 100
Profit 40%
16 100 x 0.4 = 6 440
Total for 4800 m²
22 540.00
22540.00 Rate for 1 m² = 4800
= RM 4.70/ m2 to be transfer in Bill of Quantity
55
Supply, Lay and Compact uniformly 16 mm pre coated cover aggregates as Chip Seal Layer
a)
Machinery Description
Rate per day (RM)
Days
Quantity
Total (RM)
Asphalt Paver
577
1
2
1154
7 Tonne Tandem
420
1
2
840
495
1
2
990
Roller Sweeper
TOTAL
b)
2 984
Manpower
Description
Rate per day (RM)
Quantity
Days
Total (RM)
Bitumen Worker
50
7
2
700
Operator
85
4
2
680
TOTAL
1 380
56
c)
Raw Materials (Aggregate) Descriptions Rate per tan(RM) 14 mm
38
Aggregate
Quantity Total (RM) 178.886
TOTAL
6797.67
6797.67
NOTE : -
Quantity = Area x Thickness of Aggregate x Density of Aggregate
-
Quantity = 4800 m2 x 0.014 m x 2.662 Mg/m3 = 178.886 tonne
d)
Cost for 4800 m² ITEM
COST (RM)
Machinery
2 984
Manpower
1 380
Materials
6 797.67
Cost
11 161.67
Profit 40% Total for 4 800 m²
Rate for 1 m² =
11 161.67 x 0.4 = 4 464.67 15 626.34
15626.34 4800
= RM 3.26/ m2 to be transfer in Bill of Quantity
57
SECOND LAYER Supply and lay second layer modified bitumen or equivalent for the chip seal layer: For bitumen application rate of 0.8 litres/sq.m to 1.0 litres/sq.
a)
Machinery Descriptions
Rate per day (RM)
20 Tonne Dump
570
Truck
Quantity
Days
Total (RM)
1
2
1140
TOTAL
b)
1140
Manpower Descriptions Rate per day (RM) General Labor Driver
Quantity
Days
50
2
2
200
65
2
2
260
TOTAL
Total (RM)
460
58
c)
Raw Materials (Bitumen) 1.10 litres /sq .m to 1.30 litres/sq (Average 1.2 litres/sq.m) Description
Rate per barrel (RM)
Bitumen
Quantity
Total
22
11 500
RM 500 TOTAL
11 500
NOTE:o 1 Barrel = 200 litres o 4800 m2 x 0.9litres/m2 = 4 320 litres o (4 320 litres / 200 litres) = 21.6 » 22 barrels o 4800 m2 need 22 barrels bitumen for first layer.
d)
COST for 4800m2 ITEM
COST (RM)
Machinery
1 140
Manpower
460
Materials
11 500
Cost
13 100
Profit 40% Total for 4800 m²
13 100 x 0.4 = 5 240 18 340.00
59
18340 Rate for 1 m² = 4800
= RM 3.82/ m2 to be transfer in Bill of Quantity
Supply, lay second layer modified bitumen or equivalent for the chip seal layer: For bitumen application of 0.8 litres/sq.m to 1.0 litres/sq.
a)
Machinery
Description Asphalt Paver 7 Tonne Tandem Roller Sweeper
Rate per day (RM)
Quantity Days
Total (RM)
577
1
2
1154
420
1
2
840
495
1
2
990
TOTAL
2 984
60
b)
Manpower Description
Rate per day (RM)
Quantity
50
7
2
700
85
4
2
680
Bitumen Worker Operator
Days
TOTAL
c)
Total (RM)
1 380
Raw Materials (Aggregate) Rate per tan (RM)
Descriptions 6 mm
40
Aggregate
TOTAL
Quantity
Total (RM)
76.666
3 066.64
3 066.64
NOTE: -
Quantity = Area x Thickness of Aggregate x Density of Aggregate
-
Quantity = 4800 m2 x 0.006 m x 2.662 Mg/m3 = 76.666 tonne
61
d)
Cost for 4 800 m² ITEM
COST (RM)
Machinery
2 984
Manpower
1 380
Materials
3 066.64
Cost
7 430.64
Profit 40%
7 430.64 x 0.4 = 2 972.26
Total for 4 800 m²
10 402.90
Rate for 1 m² =
10402.90 4800
= RM 2.17/ m2 to be transfer in Bill of Quantity
62
4.4.1
BILL OF QUANTITY.
PROPOSED OF DOUBLE LAYER CHIP SEAL PREVENTIVE MAINTENANANCE AT JALAN PARIT JELUTONG
ITEM
1.
DESCRIPTION
Supply and lay modified bitumen of equivalent for the chip seal layer :-
UNIT
RATE (RM)
QUANTITY
AMOUNT
m2
4.70
4800
22 560.00
m2
3.26
4800
15 648.00
(RM)
I. For bitumen application rate of 1.10 litres per square meter to 1.30 liters per square meter.
Supply, lay and compact uniformly 14 mm precoated cover aggregates as chip seal. 2. Supply and lay second layer modified bitumen or equivalent for chip seal layer: 3. II. For bitumen application rate of 0.8 litres/sq.m to 1.10/sq.m
63
Supply, lay and and compact 6mm precoated cover aggregate as chip seal layer.
4
m2
3.82
4800
18 336.00
m2
2.17
4800
10 416.00
TOTAL COST
66 960.00
Unquestionably, all of the design methods can effectively guide inexperienced personnel through the process of chip seal design. The following best practices can be drawn from a comparison of the chip seal design methodologies. To begin, the selection of the binder is a very important decision and should be made after considering all the factors under which the chip seal is expected to perform. After all, the primary purpose of a chip seal is to prevent water intrusion into the underlying pavement structure, and the asphalt layer formed by the binder is the mechanism that performs this vital function. The previously explained design methods are all based on the assumption that single-course chip seal design required the use of uniformly manner. The application rates of all methods appear to be based on residual binder and each method has a procedure for dealing with adjustments owing to factoring the loss of binder to absorption by the underlying pavement surface and the aggregate being used. Contemporary design practices need to determine binder application rated based on surface characterization,
64
absorption factors, traffic condition, climate consideration, aggregate selection, and the type of chip seal being constructed. Another important discovery is that all methods have a design objective for embedment to be between 50% and 70% of that seal’s depth. Best practices for chip seal design are difficult to isolate, because there appears to be such a large variation in practices from agency to agency. However, the following can be identified as meeting this project’s definition for best practices:
Chip seal perform best only on roads with low underlying surface distress that will benefit from this technology. The international practice is to characterize the underlying road’s texture and surface hardness and use that as a basis for developing the subsequent formal chip seal design. Where the local council responses indicated a routine use of qualitative characterization in the design process. Thus, the next logical enhancement would be to incorporate international methods to quantitatively characterize the underlying surface in the chip seal design process. One of those enhancements would be to try using the racked-in seal as the corrective measure for bleeding instead of spreading fine aggregate and sand on the bleeding surface.
65
CHAPTER 5
CONCLUSION
5.2
CONCLUSION
The conclusion in this area is quite evident. First, the selection of chip seal materials is project dependent, and the engineer in charge of design must fully understand not only the pavement and traffic conditions in which the chip seal will operate but also the climatic condition under which the chip seal will be applied. It appears that the widespread use of emulsion binder chip seal results from the nation that emulsion are less sensitive to environmental conditions during construction. Additionally, as emulsions are installed at a lower binder temperature they are probably less hazardous to the construction crew. Binder performance can be improved through the use of modifiers such as polymers and crumb rubber.
66
Next, the selection of the binder is dependent on the type of aggregate that is economically available for the chip seal project. In other way, we could to bear additional aggregate costs to ensure the quality of their chip seals are something that should be seriously considered in this area.
The aggregate should be checked to ensure that electrostatic compatibility is met with the type of binder specified. Also pre-coating of the aggregate appears to be required for use with hot asphalt cement binders to ensure good adhesion after application. Finally, it appears that the use of geotextile-reinforced chip seal is promising and should be considered for those roads that have more than normal surface distress and for which an overlay is not warranted. Therefore, several next practices can be extracted from the foregoing discussion: Conduct electrostatic testing of chip seal aggregate source before chip design to ensure that the binder selected for the project is compatible with the potential sources of aggregate. Specify a uniformly graded high-quality aggregate. Consider using lightweight synthetic aggregate in areas where postconstruction vehicle damage is a major concern. Use life-cycle cost analysis to determine the benefit of importing either synthetic aggregate or high-quality natural aggregate to areas where availability of high-quality aggregate is limited. Use polymer-modified binders to enhance chip seal performance
67
5.1
SUGGESTION
Since the failed pavement been identified and the sand patch method carried out, the design using chip seal method have been analyzed. So the best ways to solve those pavement failures are through the chip seal method, this is because of few concrete reasons which are:More durable and long lasting Protect and preserve the pavement from heavy climate weather Extend pavement life
Basically chip sealing is a common pavement preservation tactic that prevents water from seeping into an asphalt pavement's base course and sub-grade, while improving skid resistance and rehabilitating weathered asphalt surfaces. This assessment has found that chip seal practices can be instituted that will improve the reliability of maintenance chip seals. Many of the best practices identified fell in the areas of construction procedures and equipment management practice. This is not surprising, in that construction is the most critical portion of the chip seal project life cycle.
The area that apparently been surveyed which is Parit Jelutong has the greatest potential for enhancement is chip seal design. This is also the area in which advancements in technical understanding will have the greatest potential to dispel the view that the use of chip seals is merely an art. The major issue in chip seal design lies in accurately characterizing the surface on which the seal will be applied, through using engineering measurements of macro-texture and hardness.
68
APPENDIX
Measuring Distance
Length of 1km taken
Sand Patch Circle
Sand Patch Diameter Taken
Cone Been Placed
Patching To a Circullar Shape
Collecting Back The Sand
69
Shoving
Edge Drop-off
Pothole Crocodile Crack
Longitunal Crack
Cracking
70
Length of Crack Measured
Pothole
Aligator Crack
Transverse Crack
Longitunal Crack
Tranverse Crack
71
Edge Crack
Block Crack
Pothole Depth Measured
Crack Length Measured
72
REFERENCES
Garber N.J. and Hoel L.A. Traffic & Highway Engineering (3rd Edition). US: Brooks/Cole Norman Edwards, Peter Keys (1996), Singapore - A Guide to Buildings, Streets, Places, Times Books International, Victor R Savage, Brenda S A Yeoh (2003), Toponymics - A Study of Singapore Street Names, Eastern Universities Jones, Ken D., Arthur F. McClure and Alfred E. Twomey. The Types Road Failures. New York: Castle Books, 1970. Small, Kenneth A.; José A. Gomez-Ibañez (1998). Road Pricing for Congestion Management: The Transition from Theory to Policy. The University of California Transportation Center, University of California at Berkeley. pp. 213. John Shadely, Acoustical analysis of the New Jersey Turnpike widening project between Raritan and East Brunswick, Bolt Beranek and Newman, 1973 Michael Hogan, Highway Noise, 3rd Environmental Pollution Symposium
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