Technology Situation And Carrying Capacity Assessment Method Of The Reinforced Concrete Bridge

For the time being,with the modernization development promoted by technological innovation and informatization,the construction level in the field of transportation has been significantly improved.The construction of bridges in the engineering field has been advancing with the times and great progress has rapidly been made.However,in such a historical background of rapid economic development,the traffic flow is increasing.The state of overload traffic happens frequently.Under overload traffic,the existing bridge structures are often insufficient to bear,which results in local uneven force and then structural damage in various degree.Especially,the reinforced concrete(RC)bridges built in the 80 s of last century,mostly were designed with lower load levels than the current traffic loads of the road requirements,which is more likely to cause the phenomenon of insufficient bearing capacity.Due to the comprehensive effects of operating environment and overloaded traffic,the concrete structure of most RC bridges in service constantly arised decay and cracks.In severe case,the damage and fracture would occur resulting in the strength and durability of bridge structure far below the limit value.It could make the traffic unsafe on the bridge.In view of the above questions,it is extremely important to timely evaluate the structural bearing capacity of the existing RC bridge in operation and to propose accurate maintenance measures.However,how to evaluate the durability of the bridge structures in service regularly according to the current status of bridge construction development,and timely understand the active condition and health level of the bridge structure,so as to carry out related maintenance measures for the bridge,and further to improve the life cycle of bridge structures in service,is the main issue concerned by the bridge academia at present.On the basis of the existing bridge mechanics theory and relevant specifications,the load test is regarded as one of the most important detection means for bridge experts.Through the load test,the carrying capacity of bridges can be scientifically evaluated,thus to provide reliable basis for further maintenance measures.It can also make scientific evaluation for the effect of the reinforcement engineering,which can accumulate technical datas for the development and application of new structures,new design theory and construction technology.This paper introduces the technical inspection,special inspection,static and dynamic load test of a RC bridge.The structure of the simply supported cantilever girder bridge with hanging hole which across railway was checked,and then evaluation on the current technical condition and bearing capacity of the bridge were carried out.The main conclusions are as follows:1.The technical condition level of the RC bridge is assessed as four,among them the structure of unit one is four and the unit two is three.2.Based on the structure checking and the load test results,the crack width of the root of simply supported cantilever girder is greater than the standard limiting value,which can’t meet the requirements of the highway second level vehicle load.Other indicators meet the design and operating requirements.The outcome of this paper provides reference for the testing and assessment of similar bridge structure,which has a certain reference value.