套筒灌浆饱满度预埋钢丝拉拔法影响因素试验研究

Experimental study on influencing factors of sleeve grouting plumpness embedded steel wire drawing method

预埋钢丝拉拔法主要通过装配式结构套筒出浆口钢丝拉拔力大小判断套筒灌浆饱满程度,由于试验过程容易受现场施工条件干扰,评判结果的可靠性可能降低。为评价钢丝直径、锚固长度、灌浆料水灰比、养护龄期和钢丝倾角等因素对预埋钢丝拉拔法试验结果的影响,本文基于模拟测试试验进行钢丝拉拔法影响因素相关性研究。试验结果表明:钢丝拉拔力与锚固长度成正比,钢丝直径越大,单位锚固长度对应的极限拉拔荷载越大,当直径由4mm增至5mm,极限拉拔荷载增速提升80%。水灰比变化对锚固长度与极限拉拔荷载的关系影响显著,水灰比由12%变为15%,极限拉拔荷载降低约34%,且会导致套筒灌浆不饱满问题更难被检出。当灌浆料养护龄期增大时,钢丝在起始锚固段的极限拉拔荷载增速更快。钢丝倾角由0°增至5°,极限拉拔荷载增大22%~62%,易造成灌浆饱满度结果误判。结合水灰比、养护龄期等施工信息提出评定钢丝极限拉拔荷载大小的相对比值法,能够有效提高套筒灌浆饱满度评判结果的准确性。

The embedded steel wire drawing method mainly judges the fullness of sleeve grouting through the drawing force of steel wire at the outlet of the assembled structure sleeve.Since the test process is easily interfered by on-site construction conditions,the reliability of the evaluation results may be reduced.In order to evaluate the influence of steel wire diameter,anchorage length,water-cement ratio of grouting material,curing age and steel wire dip Angle on the test results of embedded steel wire drawing method,this paper conducted a study on the correlation of influencing factors of steel wire drawing method based on simulation test.The test results show that the drawing force of steel wire is proportional to the anchorage length.The larger the diameter of steel wire is,the greater the ultimate drawing load corresponding to the unit anchorage length is.When the diameter increases from 4mm to 5mm,the growth rate of ultimate drawing load increases by 80%.The variation of water-cement ratio has a significant influence on the relationship between anchorage length and ultimate drawing load.The water-cement ratio changes from 12%to 15%,and the ultimate drawing load decreases by about 34%,which makes it more difficult to detect the problem of filling sleeve grouting.When the grouting curing age increases,the ultimate tensile load of steel wire increases faster in the initial anchorage section.When the dip Angle of steel wire increases from 0°to 5°,the ultimate drawing load increases by 22%~62%,which easily leads to misjudgment of grouting plumpness.Combined with the construction information such as water-cement ratio and curing age,the relative ratio method is proposed to evaluate the ultimate drawing load of steel wire,which can effectively improve the accuracy of the evaluation result of grouting plumpness of sleeve.