The Load Transverse Distribution Of Research On The Simply-Supported Hollow Slab Bridge

The simply-supported beam bridge is the statically determinate structure, which hasspecific mechanical behavior and can adapt to regions with complete geological conditions,so it’s widely used in the national bridge construction. When the base has displacement orthe external environment temperature changes, the simply-supported bridges won’t developadditional inner force.The hollow slabs are empty near the neutral axis to reduce the dead load of the bridgestructure, then the carrying capacity of the bridge can be improved. The hollow slabs havegood bending and torsional performance and can be precast in the factories. Then the bridgecan be easily made by assembling, which can not only accelerate the construction process,but also reduce the construction cost.The simply-supported hollow slab bridges combine the advantages of thesimply-supported structures and the hollow slab structures, so this kind of bridge is widelyused in the high way construction, in the last decades, a large numbers of simply-supportedhollow slab structures are used in the national high way construction.With the elongation of the service period, different kinds of damage may occur in thiskind of the bridges, of which the damage of hinge joint is the most common. As the damagelevel increases, the whole vehicles load is undertaken by one or several slabs that directlybear this load instead of the lateral transfer of the vehicle load, which is called ‘Single PlateBearing’. The ‘Single Plate Bearing’ condition can directly reduce the bearing capacity ofthe bridge which can account for the traffic safety accidents.The analysis of the hinge joint damage can lead to the discovery of the main causes:(1) The vehicle load is improving, and under the repeated overtop external load, thehinge joints are damaged.(2) The unreasonable local design lead to the inconformity of the load lateral transferproperties in theory and in practice.(3) The drawbacks in hinge joint construction. To reduce or avoid the hinge joint damage in simply-supported hollow slab bridge, thedesign method and the construction technology both need improving. To avoid the blindnessof the improvement, it’s necessary to conduct researches in the load lateral transfer of thestructure. However, so far, there are no valid and systematic improvement measures, so it’smeaningful to conduct this kind of researches to provide some theoretical support and basicdata.This paper is based on one simply-supported hollow slab bridge of the Bridge overYitong River on Fan Rong Street in Changchun. The work conducted is as follows:1. Based on the fundamental of hinge joint method, the load lateral distributioninfluence line calculation method of the simply-supported hollow slab bridges witharbitrarily number slabs is deduced under the mechanical performance inconformity of thesideboards and the middle slabs. What’s more, the relevant calculator programs are workedout to calculate the load lateral distribution influence line of multichip hollow slabs.2. Based on the basic thought of Grillage Method, two different simulation calculationmodels of the whole bridge are established by the means of finite element method. Onemodel considers the bridge deck pavement while one doesn’t. The load lateral distributioninfluence lines of multichip hollow slabs are respectively calculated based on the twodifferent models. Then the calculation results are compared with those of the hinge jointmethod for further analysis.3. Static test is conducted for the Bridge over Yitong River and the displacements ofevery hollow slab are measured under several load conditions. Based on the measureddisplacements, the load lateral distribution characters are analyzed. Then the rationality andapplication of two kinds of load lateral distribution calculation methods separately based onthe finite element method and hinge joint method is discussed.