EXPERIMENTAL STUDY OF ELASTIC RESPONSE OF I - BEAM BRIDGE SUPERSTRUCTURE EXPERIMENTAL AND NUMERICAL SIMULATION

Bridges play a key role in the development of a nation. They are also the more costly component of a transportation system. Due to our limited resources, economy shall be given due consideration in the design process in addition to safety. To study the behaviour of bridge system, a prototype composite I-beam bridge superstructures consisting of reinforced concrete deck slab supported by four steel girders was selected and designed in accordance with the provisions of AASHTO LRFD Bridge Design Specifications. Mix design of model concrete was carried out to determine proportions of model concrete giving material properties as per requirements of the similitude.  i1oh reduced-scale model of the selected bridge system was constructed in the laboratory and instrumented with strain gages and strain gage-based displacement transducers. Static loads simulating I4I4SHTO Design Truck were applied to the model bridge through load cells and its response was measured with the help of a data logger. Numerical models of the bridge system were also developed in SAP2000 and their responses were compared with those obtained from the experiments. This paper covers mix design for model concrete, fabrication of loading assembly, and fabrication instrumentation, loading, and response measurement of reduced-scale bridge superstructure model. Responses obtained from the numerical model have also been compared with those obtained from experiment and conclusions and recommendations have been made after thorough analysis of the experimental data.