预应力锚索外锚头强化锁定技术研究

Research on the anchorage strengthened locking technique of the prestressed anchor cable

针对国内预应力锚索外锚头采用单一夹片式锚具锁定容易出现外锚锁定失效的问题,提出通过在原有夹片式锚具锁定的基础上增设附加锁固件的方式来强化锚头锁定力。附加锁固件由钢套筒和锚固胶两部分构成,通过高强锚固胶将锚具外露钢绞线端头与套筒固为一体,形成外锚头多重锁定效果,具有结构简单、受力明确、经济实用的特点。通过拉拔实验,对比分析附加锁固件张拉破坏时的受力特性,确定了附加锁固件的最优设计参数。试验证明了本方法的合理性和有效性,其结果可为新型预应力锚索锚头强化锁固技术的推广应用提供理论依据。

For the defect of the conventional clip type anchorage system in the existing prestressed anchoring construction,a new multi-locking technique of prestressed anchorage was proposed,which strengthened the anchorage locking force by adding a sleeve-type locking firmware based on the original clip locking device.The additional locking firmware used a steel sleeve and high strength anchor adhesive to anchor the steel strand ends. The ultimate tebsile capacity of different sizes of additional locking firmwares under the external load were analyzed and compared with that of the pullout test of the anchor cable to verify the validity of this new technique. Through comprehensive consideration on the tebsile capacity of additional locking firmware and the actual construction space, the optimum design parameters of additional locking firmware was determined.