Highway Research Record

IV. BRIDGE ENGINEERING
ON GOING PROJECTS
Distress Diagnostic, Performance Evaluation and Bridge Management System for Concrete Bridges

Date of Start:March 2004
Central Road Research Institute, New Delhi (R)

Scope and Objectives
To develop a suitable technology in terms of methodologies/algorithms (for development of software) and necessary hardware (instruments/techniques) applicable to different concrete highway bridges in the country, for Bridge Management System.

Methodology
The brief methodology being adopted in the project is described as below :
Although the bridges are designed taking into account effects of various geometrical and material input for their functional life, the uncertainty in loads as well as material / geometry is taken care using appropriate (partial) safety factors at the design stage. However, actual applied loads, traffic loads and / or environmental forces e.g. wind, earthquake, hydraulic forces etc. will affect the performance of the bridge. It is, therefore, important to inspect and monitor the bridge for serviceability level during the expected life span of the bridge.
Therefore, a comprehensive methodology is required to evolve the distress diagnostic and the serviceability performance of the bridge, which leads to bridge management system for a highways network. The following components are considered.
(i) Thorough visual inspection - to help creation of data bank
(ii) Non - destructive testing to arrive at causes of distress both in terms of extent and qualitatively.
(iii) Rating of the bridge and estimation of remaining life (residual strength).
Development confines to only T-beam girder, most commonly employed on highways in India. Validation of the finding will be carried out on other bridges, if possible.

Present Status and Progress
Development of visual inspection mobile unit- design : The visual inspection mobile unit has been designed considering commonly available bridges on National highways. The maximum length of the inspection arm has been considered as 10m. The unit consists of a frame consisting of ISA (angular) sections. Detailed drawings have been prepared. Other details required for fabrication and the process of fabrication is in progress.
Documentation format for project level bridge inventory: The format covering various components of a bridge has been adopted. The software module has also been prepared for this activity. It can define a road transport network and allow entering data interactively for several bridges on a network under consideration. The software module is in Graphic User Interface (GUI) mode having the back end in SQL and the front end in VB.
Strategy for visual inspection of bridges: The format of itemized checklist has been adopted from IRC recommendations. The algorithm has been prepared and the software preparation is in progress.


Significance/Utilization Potentia
There exist sufficient domestic demands of BMS.

Limitations

The development of a comprehensive software package having commercial potential is a huge activity, which involves several computer science components. In the present project, the core activities leading to a BMS methodologies and related modules would be prepared. However, the comprehensive software component in form of logic or code preparation shall be taken up in the next phase of the project.

Reports/Publications

R. K. Garg and Ram Kumar (2005), “Analysis and Design of Aerial Platform, Part-1: Design Considerations and Preliminary Design”, Interim Report: CLP 4413/ CRRI/BIE-DST (BMS1)/03-2005, March 2005.