群锚与单锚的受力特征有较大差异,而国内对混凝土化学锚栓群锚受力研究较少,相关规范和理论研究也有待完善.本文对单锚、双锚、四锚和六锚化学锚栓进行了抗拉试验,分析群锚系统对化学锚栓承载能力和破坏模式的影响.在本试验环境下,后锚固化学锚栓的破坏模式表现为:单锚和双锚试验——锚栓拉断破坏,四锚和六锚试验——混凝土破坏;混凝土强度、基材厚度及埋深一定时,随着群锚系统中锚栓数量增加,平均单根锚栓破坏荷载逐渐降低.群锚中存在锚栓受力不均匀问题和锚板刚度导致的锚栓受力增大现象,通过对试验数据的处理得到了群锚中的锚栓受力不均匀系数和锚板刚度影响系数,为锚固系统抗拉设计提供参考.%The anchor group form is different from single anchor in mechanical properties.The researches of chemical anchor bolt are quite limited in China, and the relevant norms and theoretical research are need to be improved.The tensile tests on single anchor, double anchors, four anchors and six anchors were carried out to analyze the impact of group anchor on the failure mode and tensile strength.It was observed in the present test, the failure mode of the post-installed system changed from tensile rupture of anchors (single and double anchors) to concrete fracture in case of four anchors or six anchors.With the specific concrete strength, substrate thickness and embedded depth, the averaged ultimate strength of single anchor decreases gradually with the increase of the of anchor bolts number.Furthermore, the uneven stress behavior of the anchor bolt and the improvement of anchor force caused by stiffness of fixture exist in anchor group,and the coefficients induced by uneven anchor contribution and the stiffness of anchor fixture are proposed as a reference to the practice engineering.
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