基于新型水泥基材料的全长锚固系统测试研究

Experimental research on full-length anchoring system based on a new type of cement based material

全长锚固方式相较于端头锚固方式在承载性能方面具有优势,但是受制于树脂锚固剂黏度等因素的影响,其应用有一定局限。采用实验室试验和理论分析等研究方法,提出1种新型水泥基锚固材料,该锚固材料具有早强、良好的触变性等优点,为全长锚固创造了条件。拉拨试验结果表明:这种新型水泥基锚固材料的力学性能优于传统树脂锚固剂,所形成的预应力全长锚固系统的最高拉拔强度可达普通端锚的2倍以上。声发射破坏源定位表明:随着预拉力的升高,破坏源事件总数呈降低趋势,且事件分布逐渐向杆体和锚固端头方向迁移,体现为锚杆的塑性/屈服损伤,表明高预拉力条件下决定全长锚固系统承载性的为杆体抗拉强度。

Compared with end anchoring, full-length anchoring has advantages in bearing capacity, but its application is limited due to the viscosity of resin anchoring agent and other factors. By means of laboratory test and theoretical analysis, a new type of cement-based anchoring material is proposed, which has the advantages of early strength and good thixotropy, which creates conditions for full-length anchoring. The results show that the mechanical properties of the new cement-based anchoring material are better than that of the traditional resin anchoring agent, and the highest drawing strength of the pre-stressed full-length anchoring system is more than 2 times as high as that of the common end anchorage. The damage location obtained by acoustic emission detection proved that the total damage events expressed a descending trend as the pre-tension force ascended, and the events distribution tended to gradually move to rod and bolt end, which resulted in plastic/yield injury of bolt. That is to say, the tensile strength of bolt is a decisive factor for bearing capacity of fully bonded bolting system under high pre-tension force.