THE SETTLEMENT ANALYSIS OF APPROACH SLAB OF INNOVIATIVE JOINTLESS BRIDGE UNDER TRAFFIC LOAD AND TEMPERATURE LOAD

The innovative semi-integral abutment bridges (Semi-IABs) is a new type of integral abutment bridges. Compared with the common used integral abutment bridge and semi-integral abutment bridge, it connected the bridge approach slab and the approach pavement without any expansion joints. It used the approach pavement deformation to absorb the deformation of the bridge caused by seasonal temperature change. As we all know, the differential settlement of the back-fill and the embankment soil of the end of the beam always causes bump. And the bump severely influences the safety, velocity and comfort of the rideability of the roadway and also the service durability of the bridge, even worse lead to significant traffic accidents. To analyze the effect of embankment settlements on the performance of approach slab of the innovative semi-integral abutment bridges (innovative Semi-IABs), a 3-D finite element analysis was conducted in the present study, considering the interaction between the approach slab and the embankment soil, traffic load and temperature load and also a 3-D finite element model of normal approach slab with the same size was established for comparing. Here two different settlements of the embankment were considered in the present study (s=0.001m and s=0.01m). Through the analysis, we found that innovative semi-integral abutment bridges approach slab has little relation with the increment of the settlement of the embankment. Finally this paper puts forward the effective design and construction countermeasures of the approach slab and back-fill to help improving the performance of innovative semi-integral abutment bridges and mitigating the rideability problems of the slab.