Introduction of Detailed Design of Main Bridge (for Project)

Indonesian Suramadu Bridge

Detailed Design of Main Bridge

Consortium of Chinese Contractors November, 2005



CONTENTS 1

2

3

Detailed Design....................... Design................................ ................... .................... .................... ................... ................... .................... ................ ...... 1 1.1

General Introduction........................ Introduction............................................... .............................................. .............................................. ............................... ........1 1

1.2

Technical Criteria ........................................... .................................................................. .............................................. .......................................1 ................1

1.3

Structural Design ............................................ .................................................................... ................................................ ......................................2 ..............2

Structural Analysis and Calculations .................... .............................. .................... .................... .................... ............ .. 14 2.1

Actions on the Structure .............................................. ...................................................................... ...............................................14 .......................14

2.2

Integral Analysis of the Whole Bridge ............................................... .......................................................................14 ........................14

2.3

Seismic Analysis......................... Analysis................................................. ................................................ ................................................ ................................ ........15 15

2.4

Calculation of Foundation ............................................... ....................................................................... ...........................................17 ...................17

2.5

Transverse Analysis of Pylon ........................................... .................................................................. ..........................................17 ...................17

2.6

Local Analysis of Deck ............................................... ....................................................................... ...............................................18 .......................18

2.7

Local Analysis of Anchorage System................................... System........................................................... ......................................19 ..............19

2.8

Buckling Stability Analysis ................................................ ........................................................................ ........................................21 ................21

2.9

Wind Stability Analysis .............................................. ...................................................................... ............................................... ......................... 22

Monographic Studies ................... ............................. .................... ................... ................... .................... .................... .................. ........ 24 3.1

Seismic Hazard Evaluation on Site .............................................. ...................................................................... .............................. ......24 24

3.2

Study of Seismic Dynamic Parameters ............................................. ..................................................................... .......................... 24

3.3

Geophysical Survey...................................... Survey............................................................. .............................................. .......................................25 ................25

3.4

Geological Investigation........................ Investigation................................................ ................................................ .............................................25 .....................25

3.5

Wind Tunnel Study on Wind-resistance Performance............................................. Performance................................................ ... 25

3.6

Anchoring System Analysis of Stay Cable in the Pylon ............................................26 ............................................26

3.7

Mechanics Analysis of Shear Connectors of Composite Girder ................................ ................................27 27

3.8

Underwater Topographical Survey..................... Survey ............................................. ................................................ ................................ ........27 27

3.9

Study on Topographical Evolution and Local Scour Scour Caused Caused by Suramadu Bridge ...28 ... 28

Consortium of Chinese Contractors

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CONTENTS 1

2

3

Detailed Design....................... Design................................ ................... .................... .................... ................... ................... .................... ................ ...... 1 1.1

General Introduction........................ Introduction............................................... .............................................. .............................................. ............................... ........1 1

1.2

Technical Criteria ........................................... .................................................................. .............................................. .......................................1 ................1

1.3

Structural Design ............................................ .................................................................... ................................................ ......................................2 ..............2

Structural Analysis and Calculations .................... .............................. .................... .................... .................... ............ .. 14 2.1

Actions on the Structure .............................................. ...................................................................... ...............................................14 .......................14

2.2

Integral Analysis of the Whole Bridge ............................................... .......................................................................14 ........................14

2.3

Seismic Analysis......................... Analysis................................................. ................................................ ................................................ ................................ ........15 15

2.4

Calculation of Foundation ............................................... ....................................................................... ...........................................17 ...................17

2.5

Transverse Analysis of Pylon ........................................... .................................................................. ..........................................17 ...................17

2.6

Local Analysis of Deck ............................................... ....................................................................... ...............................................18 .......................18

2.7

Local Analysis of Anchorage System................................... System........................................................... ......................................19 ..............19

2.8

Buckling Stability Analysis ................................................ ........................................................................ ........................................21 ................21

2.9

Wind Stability Analysis .............................................. ...................................................................... ............................................... ......................... 22

Monographic Studies ................... ............................. .................... ................... ................... .................... .................... .................. ........ 24 3.1

Seismic Hazard Evaluation on Site .............................................. ...................................................................... .............................. ......24 24

3.2

Study of Seismic Dynamic Parameters ............................................. ..................................................................... .......................... 24

3.3

Geophysical Survey...................................... Survey............................................................. .............................................. .......................................25 ................25

3.4

Geological Investigation........................ Investigation................................................ ................................................ .............................................25 .....................25

3.5

Wind Tunnel Study on Wind-resistance Performance............................................. Performance................................................ ... 25

3.6

Anchoring System Analysis of Stay Cable in the Pylon ............................................26 ............................................26

3.7

Mechanics Analysis of Shear Connectors of Composite Girder ................................ ................................27 27

3.8

Underwater Topographical Survey..................... Survey ............................................. ................................................ ................................ ........27 27

3.9

Study on Topographical Evolution and Local Scour Scour Caused Caused by Suramadu Bridge ...28 ... 28


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1 1.1


Detailed Design General Introduction

Suramadu bridge is located in the northern part of east Java province of Indonesia. It spans Madura Strait and connects Surabaya with Madura island.

The main bridge is cable stayed bridge with steel-concrete composite beam and twin tower pylons and twin cable planes. The span arrangement is 192+434+192m=818m. The approach bridge at each side is prestressed concrete continuous beam with box section and span length 40+7×80+40m=640m. Main bridge and approach a pproach bridge are connected with the V-pier. V-pier.

1.2

Technical Criteria Criteri a

(1) Design safety level: level I; (2) Design reference period of the bridge: 100 years; (3) Design running speed of vehicle: 80km/h; (4) The width of bridge deck: dual running, 0.4m (side parapet) + 3.05m (pedestrian and motorcycle way) + 1.3m (side reserve) + 9.75m (carriageway) + 1m (central reserve) + 9.75m (carriageway) + 1.3m (side reserve) + 3.05m (pedestrian and motorcycle way) + 0.4m (side parapet) = 30m; (5) Longitudinal gradient of deck: ≤1%; (6) Transverse gradient of deck: 2%, two-way slope; (7) Navigation headroom: 400×35m; (8) Vehicle Vehicle load: Highway-I class in i n JTG D60-2004; (9) Load on motorcycle way: For integral structural analysis, p = 4.0kPa; for calculating members directly acted by pedestrian load, p = 5.0kPa; (10) Wind load: basic wind velocity is 27m/s; (11) Design criteria of earthquake resistance Level I: For 10% exceeding probability within 50 years (475 years return period), horizontal peak acceleration at ground surface PGA = 0.15g; Level II: For 2% exceeding probability within 50 years (2500 years return period), horizontal peak acceleration at ground surface PGA = 0.24g; Consortium of Chinese Contractors

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(12) Ship collision force Collision with 30° angle to the surface of foundation: collision force = 14356kN; Collision perpendicular to the surface of foundation: collision force = 8282kN; (13) Temperature action Maximum system temperature is taken to be 40.0°C, minimum system temperature is taken to be 15.0°C, reference temperature is taken to be 30.0°C.

1.3

Structural Design

1.3.1

Structural system

The main bridge is in floating system. Vertical bearings are set only at side piers. To limit the movement along the bridge, longitudinal earthquake-resistance dampers are set at pylon towers. In transverse direction, rubber positive blocks are arranged between main girder and pylon shaft at pylon, and concrete stoppers are set on the V-pier to restrain the transverse movement at bridge end.

Figure 1.3.1-1 shows the general arrangement of the main bridge, and Figure 1.3.1-2 shows the typical cross section of deck.

1.3.2

1.3.2.1

Superstructure

Steel girders

Steel girders are composed of main girders, floor beams and stringers. In the cross section of the bridge, 2 main girders are arranged at outer side and 2 stringers at inner side. For standard segment, floor beams are set every 4m along the bridge. Connection between main girders, floor beam and main girders, and stringer and floor beams all adopts high strength bolts.

Steel main girder is in welded box section. For ordinary segments, the height at the central line of the box is 2800mm, and 2% transverse slope, same with the deck slab, is set on the top flange. Transverse distance between the outsides of webs is 2300mm. To meet the needs of fabrication and connection with floor beams, the actual width of top flange and bottom flange is all 2420mm. Consortium of Chinese Contractors

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Figure 1.3.1-1 Consortium of Chinese Contractors


General Arrangement of Superstructure -3-


Figure 1.3.1-2


Typical Cross Section of Deck

Floor beam and stringer all adopt welded I-section, including top flange, web, and bottom flange.

1.3.2.2

Deck slab

Concrete deck slab comprises two parts: prefabricated slab and cast-in-situ slab. The thickness of prefabricated slabs is 250mm, and the thickness of cast-in-situ slab is 270mm. When installing the prefabricated slabs, the top surface should be aligned with the design surface of cast-in-situ slab, and supported on the top flange of steel girders via Φ20mm rubber band to prevent the cement paste from leaking when cast the joint concrete.

Transverse prestressing tendons are arranged in concrete deck slab in the whole bridge. At bridge end and mid span where horizontal components of stay cables are small, longitudinal prestressing tendons are also arranged in the deck slab.

1.3.2.3

Pylon tower

The pylon tower is in door shape including tower seat, lower pylon shafts, mid pylon shafts and upper pylon shafts. The total height is 141.331m. Lower transbeam between the lower and mid pylon shafts, mid transbeam between the mid and upper pylon shafts, and upper transbeam between the upper pylon shafts are set. Pylon shafts and transbeams are all in hollow box section.


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Figure 1.3.2.3 shows the general dimensions of pylon tower.

Figure 1.3.2.3

1.3.2.4

Pylon Tower

Stay cable

Cross section of stay cable is galvanized parallel steel wires of Φ7mm with high strength, and extruded with two layers of high density polyethylene, of which the inner layer is in black, and Consortium of Chinese Contractors

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the outer layer in color. Standard strength of steel wires is f pk =1670MPa.

Stay cable is tensioned at the pylon end and fixed at the main girder end, and cold cast anchor devices are adopted to anchor the cable. Distance between anchor points of stay cable in the pylon is 2.2m, in the main girder along the bridge is 12m for standard girder segment.

General design drawing of stay cable is shown in Figure 1.3.2.4-1.

Figure 1.3.2.4-1

Stay Cable

To control the vibration of cable, vibration absorber is placed in the cable sleeve, and the surface of outer HDPE sheath is set as bifilar helix. In addition, according to the actual situation and measured vibration properties of cables after bridge completed, HCA viscid dampers will be also installed outside to lessen the vibration. Figure 1.3.2.4-2 is the diagram of HCA damper installed between stay cable and deck.


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Figure 1.3.2.4-2

1.3.2.5

HCA Viscid Damper

Anchorage of stay cable

Except stay cables SC16 and SC17 which are anchored in the counterweight concrete block at bridge end, at the lower end of other cables, steel anchor boxes, composed of anchor plates, cushions, bracing ribs, and stiffeners, are all set for the cables in the main girders.

Figure 1.3.2.5-1 is the illustration of half of an anchor box and the main girder.

Figure 1.3.2.5-1 Consortium of Chinese Contractors

Steel Anchor Box and Main Girder -7-



In the pylon tower, steel anchor beams and loop prestressing tendons are adopted for the anchorage system respectively. For C0, SC1, MC1, SC2 and MC2, stay cables are anchored on the corbels extruded from the inner wall of tower, and loop prestressing tendons are used to reinforce the concrete. Other cables are all anchored with the steel anchor beams inside the pylon shaft.

Figure 1.3.2.5-2 is the illustration of a steel anchor beam in the pylon shaft.

Figure 1.3.2.5-2

1.3.2.6

Steel Anchor Beam in the Pylon Shaft

Bearing

2 sets of earthquake-resistance steel spherical bearings are arranged under the main girders at each side pier of main bridge, of which one is movable in two directions, and the other is movable in longitudinal direction and fixed in transverse direction. Vertical supporting capacity of one bearing is 8000kN, and horizontal supporting capacity of the transversely fixed bearing is 6000kN. Maximum movement of bearing along the bridge is ±60cm, and the maximum rotation angle is 0.02rad.

Figure 1.3.2.6 shows an assembled steel spherical bearing to be installed. Consortium of Chinese Contractors

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Figure 1.3.2.6

1.3.2.7


Earthquake-resistance Steel Spherical Bearing

Longitudinal damper

2 longitudinal viscous dampers are set under the main girders at each pylon tower. Main parameters of damper are: exponent of velocity,

α

= 0.4; damping coefficient, C = 3000kN

(m/s)-0.4; normal damping force, F = 2400kN; length of stroke (mm) ±600; minimum safety factor of damping force = 1.5.

Figure 1.3.2.7 shows an example of the longitudinal damper installed under steel girder.


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Figure 1.3.2.7

1.3.2.8


Longitudinal Viscous Damper

Expansion joint

For the main bridge, expansion joint at bridge end should adapt to the large and complex movements under different load cases. The joint should not only follow the main movement along the bridge but also distinctive movements in the 2 spatial directions perpendicular to the main direction. Even rotations of the bridge about the three special axes should also be easily coped with.

To meet the requirements above, Maurer swivel-joist expansion joint is to be chosen the bridge. With special seismic devices, the expansion joint can also be used under seismic action.

Figure 1.3.2.8-1 is schematic drawing of the swivel-joist expansion joint, and Figure 1.3.2.8-2 shows the state when the expansion is being installed.


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Figure 1.3.2.8-1

Figure 1.3.2.8-2

1.3.3


Swivel-joist Expansion Joint

Expansion Joint Being Installed

Substructure

Figure 1.3.3 shows the general arrangement of piles and pile cap of pylon.

Piles foundation is cast in-situ, and the holes are formed using steel pile casings. The diameter of piles is 2.4m, and the minimum distance between piles from center to center is 6m. There are 56 piles for every pylon.

Dimension of pile cap normal to the bridge direction is 57.2m, 34m along the bridge, and 6m


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in thickness.

Figure 1.3.3

1.3.4

General Arrangement of Pile Cap and Foundation

Prevention of corrosion for steel structure

Climate at the bridge site belongs to typical tropical rainforest climate. The major natural corrosive mediators to steel structure are chloride ion, oxygen, moisture and strong ultraviolet ray. For the external surface of steel structure, coating to prevent corrosion includes: 1 coat of inorganic zinc silicate primer at workshop (20µm), 2 coats of improved epoxy zinc rich primer (2×40µm), 2 coats of MIO epoxy undercoating (2×50µm), and 2 coats of polyurethane top coating (2×50µm). The total thickness of dry film is 300µm.

To protect the inner box surface of main girders and steel anchor beams in the upper shafts, and to prevent the anchor devices from corrosion, dehumidifiers will be placed in the upper shafts of pylon towers and the box section of main girders.

1.3.5

Construction method


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1.3.5.1


Pile foundation

Hole of pile will be drilled on the off-shore platform and protected with steel casing. Underwater concrete will be cast in-situ continuously and under strict control. Quality of pile will be checked using ultrasonic testing method, and the bearing capacity will be tested with Osterbog method.

1.3.5.2

Pile cap

Pile cap is to be constructed with steel caisson. Since the pile cap is a bulk concrete structure, influence of hydration heat on the quality of pile cap must be effectively decreased. The pile cap will be cast with several layers and cooling circulation water pipes will be placed to control the temperature.

1.3.5.3

Pylon tower

Roll-over and climbing formwork methods are to be used for the construction of pylon tower.

1.3.5.4

Deck girders

Steel girders and concrete deck slab of the bridge will be constructed with balancing cantilever method segment by segment. Temporary bracket at pylon and bridge end and temporary pier at side span will be set up to assist installing the girders.


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2


Structural Analysis and Calculations

2.1

Actions on the Structure

Structural actions include: permanent action, variable action, and accidental action. Classification of the structural actions in detail is shown in Table 2.1. Combinations of all possible actions will be used in the design.

Table 2.0

2.2

No.

Classification of Actions

Permanent action

Variable action

Accidental action

1

Self-weight of structure (including superimposed dead load)

Vehicle load

Collision force of ship or drifter

2

Prestressing force

Vehicle impact force

Collision force of vehicle

3

Concrete shrinkage and creep

Soil lateral pressure caused by vehicle

Seismic action

4

Water floatage force

Pedestrian load (including motorcycle)

Dynamic rupture force of stay cable

5

Foundation settlement

Vehicle braking force

6

Wind load

7

Water pressure

8

Temperature effect

9

Bearing frictional resistance

10

Static rupture force of stay cable

11

Replacement of stay cables

Integral Analysis of the Whole Bridge

In integral analysis of the whole bridge, co-operation of steel girders, stay cables, deck slab (including prestressing action in it) and pylon towers are taken into consideration. In accordance with the actual construction procedures, the whole structure is analyzed using programs MIDAS, and statuses of construction step by step and service are simulated respectively.

Totally 564 elements are divided for the whole bridge, in which girder and pylons use beam elements, stay cables use cable element, and pile foundation of pylon is incorporated in the Consortium of Chinese Contractors

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integral model by simulating it as gantry structure in the rule of equivalent displacement. Figure 2.2 is the analysis model of the whole structure.

Figure 2.2

2.3

Integral Analysis Model of the Whole Structure

Seismic Analysis

Seismic analysis of the main bridge includes the selection of parameters of damper, structural analysis under seismic action and evaluation of earthquake-resistance performance of structure. The structure is three-span continuous composite girder cable stayed bridge with totally floating system and twin pylons, i.e., girder can float longitudinally relative to the pylon but is restricted by the pylon, and girder can slide on the side pier in longitudinal direction.

Main girder and pylons are simulated with space beam element, and stay cables are simulated with truss elements, but allowing for the effects of sagging of cables and geometric stiffness due to dead load. Main girder and pylon are relatively free in longitudinal direction, and connected with springs in transverse direction.

For the pile group foundation, two methods are adopted to simulate the interaction among pile, soil and superstructure. One method is to use 6 springs to imitate the restraints of pile to the pylon along and about three directions, the other is to fix the piles under a certain distance below the scouring line.

Time-history analysis is carried out to calculate the structure under horizontal and vertical earthquake action. The input time-history curves are synthesized targeted at response spectrum. Consortium of Chinese Contractors

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Seismic analysis models with the two methods are shown in Figure 2.3.

(a) Six-spring model

(b) Pile fixed model Figure 2.3


Seismic Analysis Models

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2.4


Calculation of Foundation

Piles are designed as friction type. Pile group is calculated with “m” method, and allowable bearing capacity of one pile is calculated in accordance with Equation 2.4:

[ P] =

1 2

( Ul τ

+

A σ ) R

(2.4)

where U is the parameter of pile, l is the length of pile under local scouring line, A is the cross sectional area of pile,

τ p

is the average ultimate friction force of soil around the pile, and

σ p

is

the ultimate bearing capacity of soil at pile tip.

2.5

Transverse Analysis of Pylon

In addition to the integral analysis model of the whole bridge which will calculate the pylon in longitudinal direction, transverse analysis model is also formed to calculate the pylon under the most unfavorable load combinations of dead load, cable force, wind and temperature, etc. Transbeams of pylon are fully prestressed concrete structure, and pylon shafts are ordinary reinforced concrete structure. Stress of transbeams and strength of pylon shafts at different load cases are checked in the calculations.

Figure 2.5 is the transverse analysis model of pylon.


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2.5

2.6

Transverse Analysis Model of Pylon

Local Analysis of Deck

In order to get to know the stress distribution of each main components of composite grider, especially in deck slab, certain length of deck girders under the pylon and at bridge end are chosen to carry out the local analysis, respectively. Space models are built up and block, shell and 3-D frame elements are adopted to simulate the structure, and main girders, floor beams, stringers, deck slab and anchor boxes are all incorporated.

Figure 2.6 is the local analysis model of deck under the pylon.


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Figure 2.6

2.7

2.7.1


Local Analysis Model of Deck under Pylon

Local Analysis of Anchorage System

Steel anchor box in the main girder

To calculate the local stress of anchor box in the main girder under the cable force, analysis models of anchor boxes for different specifications of cables are formed, and stress fluctuation in anchor box and main girder is acquired for different anchor boxes along the bridge. Figure 2.7.1 is a local analysis model of anchor box in the main girder.

(a) The whole model (half)


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(b) Anchor box (half) Figure 2.7.1

2.7.2

Local Analysis Model of Anchor Box in Main Girder

Steel anchor beam in the pylon

For different types of anchor devices and steel anchor beams, several models are built up to calculate the stress in the steel anchor beams under different load combinations. Figure 2.7.2.2 shows a local analysis model of steel anchor beam in the pylon.

Figure 2.7.1

Local Analysis Model of Anchor Box in Main Girder


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2.8


Buckling Stability Analysis

To calculate the structural buckling stability both under construction and at service stage, three the most unfavorable states are considered in the structural analysis model: service state, the longest single cantilever state (at mid span) at construction stage, and the longest double cantilever state at construction stage. Figure 2.8-1 and 2.8-2 show the calculation models of the latter two states.

Figure 2.8-1

The longest Single Cantilever State (at Mid Span) at Construction Stage


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Figure 2.8-2

2.9


The longest Double Cantilever State at Construction Stage

Wind Stability Analysis

To ensure the structural safety of the bridge during construction and service stage, the bridge is analyzed to check the wind stability, including:

(1) To determine of wind speed parameters for wind resistance study;

(2) Modal analysis

(3) To check flutter stability of the bridge and determination of the aerodynamic derivatives of the bridge deck for both the service state and the most unfavorable construction state;

(4) To study the performance of vortex-excited resonance of the bridge at both the service state and the construction state;

(5) To determine the aerodynamic coefficients of the bridge deck at both the service state and the construction state;

(6) To perform CFD simulation of the deck of the bridge, and compare the CFD results with Consortium of Chinese Contractors

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the test results.

Table 2.9 shows the calculation models for different states and using different simulation methods.

Table 2.9 State

Calculation Models of Wind Stability Analysis Triple Girder Model

Single Spine Girder Model

Service State

Longest Single-cantilever State

Longest Double-cantilever State


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3 3.1


Monographic Studies Seismic Hazard Evaluation on Site

Main work of seismic hazard evaluation includes:

(1) Investigation, survey and analysis of earthquake fault and its impact analysis in the near field region;

(2) Engineering geological survey in field region;

(3) Analysis and evaluation of seismic-geological catastrophe at the location of the bridge;

(4) Fatalness analysis of earthquake, response analysis of soil layer, and determination of dynamic parameters at the location of bridge for design purpose.

3.2

Study of Seismic Dynamic Parameters

The study is to determine the design earthquake motion parameters, which correspond to the earthquakes of return period of 475 and 2500 years, respectively. Study report of seismic dynamic parameters will provide the following results:

(1) Horizontal PGA and its exceeding probability curve;

(2) Horizontal and vertical design acceleration response spectra (critical damping is 0.05 and 0.02, period not less than bridge’s natural period) at the base of pylon tower;

(3) Duration of earthquake motion which contains 95% of the total energy;

(4) Several groups of time-history curves;

(5) Horizontal shear-wave velocity and horizontal compression-wave velocity.


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3.3


Geophysical Survey

The objectives of geophysical survey are as follows:

(1) To divide and compare vertically and horizontally the rock layer within the pylon area, and determine the engineering category of the site.

(2) To find out the fault features at pylon area.

(3) Combined with measurement of wave speed inside the hole and dynamic 3-axis test, to determine the earthquake guarding level at the pylon area.

3.4

Geological Investigation

Main purposes of geological investigation are:

(1) To determine the subsurface stratigraphy and stratigraphic relationships (and their variability);

(2) To obtain lithological and mechanical characteristic of soil;

(3) To give comprehensive information for suitable foundation system;

(4) To evaluate the investigating and testing data and provide solutions to the geotechnical problems.

3.5

Wind Tunnel Study on Wind-resistance Performance

To ensure the wind-resistant safety of the bridge under construction and during service stage, wind tunnel study mainly includes the following parts:

(1) Determination of wind speed parameters for wind resistance study; (2) Modal analyses of bridge structure; (3) Wind tunnel study on wind-resistant performance; Consortium of Chinese Contractors

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(4) Full bridge aeroelastic model test.

Figure 3.5 shows the sectional models in the wind tunnel test.

a. Sectional model at construction state

b. Sectional model at service state Figure 3.5

3.6

Sectional Model in the Wind Tunnel Test

Anchoring System Analysis of Stay Cable in the Pylon

For different anchorage systems in the pylon, main contents of the study are as follows: Consortium of Chinese Contractors

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(1) Comparison of several kinds of anchorage systems. Steel anchor beam, steel anchor box and loop prestressing concrete are compared.

(2) Steel anchor beam in the pylon. Strength and rigidity of steel anchor beam, bearing c apacity of concrete corbel under steel beam, and strength and reinforcement of concrete pylon wall will all be checked under the maximum cable force and other load cases such as replacing the cable or rupture of one cable.

(3) Prestresed concrete structure for anchoring the cables. Patterns to prestress the concrete pylon will be compared and determined, and strength of pylon wall under cable forces will be checked.

3.7

Mechanics Analysis of Shear Connectors of Composite Girder

Mechanics analysis of shear connectors of composite girder mainly aims at:

(1) Studying the behavior of the studs between the box girder and concrete slab, quantitatively analyzing the shear strength of stud shear connectors, especially for studs at the girder section where there are cables.

(2) Analyzing the shear strength of stud shear connectors on the floor beams and stringers.

(3) According to the result, analyzing if the arrangement and number of stud shear connectors on the steel girders are reasonable.

3.8

Underwater Topographical Survey

Main tasks of underwater topographical survey include:

(1) By investigating and collecting the existing marine chart information, to verify whether the existing data could meet the requirements for the study of sea bed evolvement and hydrograph analysis;


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Introduction of Detailed Design of Main Bridge (for Project)

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