混凝土结构四筋植筋粘结锚固性能试验研究

Experimental research on bonded anchorage behavior of four planting bars in concrete structures

为了研究植筋间距、边距对多筋植筋粘结锚固性能的影响,以植筋间距、植筋边距为设计参数,设计制作了9组四筋植筋混凝土结构试件,并进行了四筋植筋混凝土结构拉拔试验,分析了植筋间距、边距对四筋植筋混凝土结构的破坏形态、粘结锚固性能及拉拔承载力等的影响。试验结果表明,所有的四筋植筋混凝土结构试件均为复合粘结破坏。其他条件相同,四筋植筋拉拔承载力随着植筋间距的增大或植筋边距的增大而提高,但四筋植筋拉拔承载力小于单筋植筋拉拔承载力与植筋数量的乘积,存在群锚效应。在试验结果分析的基础上,考虑四筋植筋间距、边距的影响,建立了四筋植筋拉拔承载计算模型和计算公式,计算值与试验值吻合较好,可以用来计算四筋植筋混凝土结构拉拔承载力。

In order to research the effect of planting bar spacing and edge spacing on the bonded anchoring behaviors of multi-planting rebars concrete structure,9 groups of four planting bars concrete structure were designed and made by taking the planting bar spacing and the edge spacing as the design parameters,and the pull test of the concrete structure with four planting bars was carried out.The influence of the planting bar spacing and edge spacing on the failure model,bond anchoring behavior and pull-out bearing capacity of four planting bars concrete structures is analyzed.The test results show that all the four-planting bars concrete specimens are composite bond failure.Other conditions are the same,the pull-out bearing capacity of the four planting bars increases with the increase of the planting bar spacing or edge spacing,but the pull-out bearing capacity of the four planting bars is smaller than that of single planting bar and the number of planting bar,and there is group anchor effect.Based on the analysis of the test results,the calculation model and calculation formula are established by considering the influence of the planting bar spacing and edge spacing of the four planting bars.The calculated value meets the test value,which can be used to calculate the pull-out bearing capacity of the four planting bars in concrete structure.