预应力混凝土双压花锚具性能的低周重复荷载试验研究

An experimental study on the performance of the double-ball anchorage system in prestressed concrete structures under repeated loads

通过对预应力混凝土一种新型双压花锚具足尺寸试件的试验,研究了这种锚具在低周重复荷载下的性能及其特点、锚具受周期荷载后再次承受静力荷载作用时的性能以及周期荷载的不同应力循环幅度对锚具性能的影响。试验结果表明:双压花锚具达到了国家标准规定的周期荷载性能要求;随着周期荷载循环次数的增加,锚具每个循环的荷载与变形关系呈近似线弹性关系;锚具在历经50次重复加卸荷后,其静载性能发生了很大变化,而最大承载力和极限变形能力没有降低。

Full-size specimens of the double-ball anchorage system used in prestressed concrete structures were tested. Its performance under repeated loads, the static behavior of the anchorage ever subjected to the repeated loads and the influence of different ranges of the stress fluctuation on its performance are studied. The tested results are shown that： the double-ball anchorage meets the requirement for the repeated loading tests specified in the code; with increasing numbers of the loading cycles, its load-deformation relationship in each cycle loading behaves nearly in linear-elastic; over the repeated loads of 50 cycles is resulted in significant changes of the static behavior of the anchorage, but its maximum load-carrying capacity and ultimate deformation capacity are not decreased.