不同保护层厚度下钢筋混凝土板受力性能试验研究

Experimental research on behavior of reinforced concrete slabs with different concrete cover thicknesses

在实际施工过程中,混凝土板负弯矩钢筋的保护层厚度容易偏大,这将导致板(特别是悬臂板)的承载力降低.对钢筋混凝土悬臂板和两端约束板进行了试验研究,重点研究了保护层厚度变化对板的承载力及正常使用性能的影响.对两端约束板分别按线弹性理论和塑性内力重分布理论进行了计算;利用ANSYS进行了有限元数值模拟,并与试验结果进行了对比分析.研究结果表明,板的保护层厚度对悬臂板的受力性能有较大的影响,对两端约束板的受力性能虽有影响但并没有对悬臂板的影响那样明显.研究成果对于丰富板的计算理论及保护层施工与验收标准的制定均有一定的积极意义.

In the construction site,the concrete cover thickness of the negative reinforcements of concrete slab is usually bigger than design value,which will lower the maximum bearing capacity of slab（especially for the cantilever slab）.An experimental research on reinforced concrete slabs（cantilever slabs and slabs whose two ends are both fixed） with different concrete cover thicknesses was designed.The effect on bearing capacity and service performance of the reinforced concrete slabs caused by the concrete cover thickness change was studied.The slabs whose two ends are both fixed were calculated on the basis of linear elastic theory and plastic moment redistribution theory respectively.The software ANSYS was utilized for FE simulation and the simulation results were compared with experimental results.The test results indicate that the cantilever slab thickness has obvious impact on its performance,and the extent of impact on the slab with two fixed ends is not as obvious as that on cantilever slab.Through the analyses of the test data,some conclusions are deduced,which will be helpful to the construction check and related theory research.