服役框架结构增层可靠性评估

基于服役结构荷载和抗力水平的时变性,提出了服役结构增层改造项目必须要考虑时间因素影响的观点·通过对混凝土碳化、钢筋锈蚀、截面几何尺寸的损伤以及钢筋与混凝土的黏结强度的降低等多因素影响机制下,服役结构增层动态可靠度分析,给出了建筑物增层可行性的时变结论·并与框架空间程序TAT的计算结果进行对比,表明了所提方法的正确性·

Reliability Assessment of Adding Storey onto the Frame Structure of a Building in Service

Based on the time-dependent load acting on the frame structure of a building in service and the resistance to it, an argument is set out that the time influence on adding a storey to the building must be taken into account. A dynamic reliability assessment is done for adding a storey onto the frame structure of a building in service, including such influencing factors as the carbonization of concrete, corrosion of reinforcements, reduction in size of cross-sections and strength reduction of concrete and reinforcements. A time-dependent conclusion is therefore drawn that adding a storey onto the top of such a building is feasible if the assessment is qualified. Moreover, the results of the assessment mentioned above are in good accordance with TAT program, thus showing the correctness of argument as set out.