REINFORCED CLOSE JOINT CONSTRUCTION MEASURES OF SUPERIMPOSED SLABS AND ITS FLEXURAL PERFORMANCE SIMULATED BY FEM

In order to optimize the joint structure of superimposed slabs and analyze the flexural performance of the joint, three locally strengthened joint construction measures were proposed. Three specimens of the reinforced superimposed slabs were designed and tested under static load. The nonlinear finite element analysis of the specimens was carried out by ABAQUS software and compared with the test results. The results showed that the crack distribution, failure mode and flexural capacity of the superimposed slabs were in good agreement with the test results. Based on the finite element model, the parametric analysis of the flexural bending capacity were conducted on the superimposed slabs with groove joint. The influences of the reinforcement ratio, the thickness of the cast-in-place layer, the depth of the groove and the overlapping length of the joint reinforcement on the bearing capacity of the superimposed slabs were investigated.The results showed that the reinforcement ratio, the thickness of the cast-in-place layer and the depth of the groove had a significant impact on the bearing capacity of the superimposed slabs, and the overlapping length of the joint reinforcement had a impact on the bearing capacity of the superimposed slabs. When the overlapping length was less than 1.4l_a (1.4l_a was defined as the anchorage length of tensile bar), the bearing capacity increased with the increase of overlapping length. When the overlapping length was greater than 1.4l_a, there was little impact on the bearing capacity.