MINOR PROJECT REPORT

ON

Analysis and Design of cable Stayed Bridge Using Staad PRO.

Outlines of the Minor Project Report

Objectives of the study

Scopes of the study

Flow chart of the study

Component parts of the cable-stayed bridge

Design procedure

Implementation program

Expected outcomes

Objectives of the study

To get knowledge on design and analysis of a superstructure of cable-stayed highway

bridge

To know the components of cable-stayed bridge

To have some knowledge of the design specifications for highway bridge published by

American Association of State Highway and Transportation Officials (AASHTO)

specifications

To get better knowledge on practices and standards in bridge design

To get detail information on the variation of joint forces in stiffening truss of cable-

stayed bridge

To be skillful for the way how to use STAAD-Pro software

Scope of the study

Only superstructure of cable-stayed bridge will be designed

AASHTO design specifications and HS 20-44 loading will be used

The preliminary design and joint design will be done by STAAD-Pro software

The effect of thermal change, wind force and earthquake effect will be considered

The variation of joint forces in stiffening truss which mainly supports the floor of

cable-stayed bridge are determined

Anchorage, substructure and construction methods are not involved in this study

Literature Study

Design Configuration

Modeling for Analysis

Construction Methods and Procedures

Analysis and Design

Final Design and Result

Fig. Flow chart of the study

Component Parts of Cable-Stayed Bridge

1. Cables

2. Cable System

3. Pylon

4. Stiffening girder or Truss

5. Cable anchorage and Connection

Types of cables

Cables

Cables are the most important elements of a cable-stayed bridge.

They carry the load of the girder and transfer it to the tower and the

back-stay cable anchorage.

Cables are tension members.

New Parallel Wire Strand

Locked coil Strand Helical Strand Bar Bundle

Seven Wire Strand

Cable System

Three basic arrangements have been developed for the longitudinal

layout of the stay cables. They are

Radial System

Harp System

Fan System

Number of Cable Planes

The three basic transverse cable of configurations are following;

(a) Single Plane

(b) Double Plane

(c) Triple Plane

Pylon or Tower

The design of the pylon must adapt to the various stay cable layouts.

The primary function of the pylon is to transmit the force arising from

anchoring the stays and these forces will dominate the design of cables.

Tower configurations for single-plane cable

Tower configurations for single-plane cable

Tower configurations in the case of the high installation position for girder

Stiffening Girder

The role of the stiffening girder is to transfer the applied loads, self

weight as well as traffic load, into the cable system.

The traffic load is acting on the deck of the girder, and both the dead

load and wind area in most cases are larger for the girder than for the

cable system.

Stiffening girders may be I girders, trusses and box girders.

The stiffening truss will be made as a space truss comprising four

chords connected by four diagonal bracings, two vertical and two

horizontal.

Bracing System

The bracing system used in stiffening trusses are generally the same

as found in the other trusses with constant depth.

Three types of bracing system for the vertical main trusses . They

are

1. Warren truss

2. Pure warren truss

3. Pratt truss

(a) (b) Warren truss

Pratt truss Pure warren truss

Figure; Relevant Bracing Systems for the Main Trusses

Bridge Type - Cable-Stayed Bridge

Total Length of Bridge - 200 m

Span Arrangement - 3 spans arrangement

Main Span - 100 m

Side Span - 50 m (each)

Clear width - 10m

Side Walk Width - 1.5 m (each)

Pylon (or) Tower - H Type

Truss Type - Warren Truss Type

Cable type - 7̋ΦParallel Wire Strands

Cable System - Fan type

Design Procedure

Implementation Program

Literature study on proposed bridge

Configuration of proposed bridge

Preparation for analysis of bridge

Modeling analysis of bridge using STAAD-Pro software

Model of Cable Stayed bridge in Staad PRO

Assigning Support in Model

Assigning of Material in Model in Staad PRO

Assigning of Material in Model in Staad PRO

Assigning cable properties in Model

Designing Slab deck properties in Model

Loading done in Model

Work to do

Analysis is to be done for: • Displacement

• Bending Moment Diagram • Axial stress • Bending stresses • Combined axial and bending stresses • Forces in each member of bridge

THANK YOU

Made By: Abhishek Anand Divyani Saini Mohammad Qasimuddin Mohmad Mohseen Lovnish Khyaliram Ritul shrivastava Shubham Gusain

Submitted To: Dr. Deep Gupta Head of Department, Civil Engineering, College of Engineering Roorkee