预应力锚索抗滑桩抗震优化设计与试验研究

据汶川灾后调查发现,预应力锚索抗滑桩具有较好的抗震表现;但在地震的作用下,部分桩仍出现锚索锚头失效现象。为了解决锚头失效问题和提高锚索抗滑桩的抗震性能,结合中国抗震规范及结构抗震设计规范,对预应力锚索抗滑桩给予优化设计,并开展大型振动台试验进行试验验证。结果表明:(1)从震后桩头倾角来看,在锚索抗滑桩锚头与桩间设置消能弹簧可在一定程度上缓解锚头失效问题。(2)桩后设置EPS材料可以减小受力侧动土压力;且其缓冲消能效果跟输入的动峰值加速度相关,输入的动峰值加速度越大,缓冲消能效果减弱。(3)通过试验现象及实测结果分析可以得出,上述优化措施是行之有效的,可以为高烈度地震区锚索抗滑桩设计提供参考。

Seismic Optimum Design and Experimental Research on Anti Slide Pile With Pre-stressed Anchor Cable

According to the Wenchuan post disaster investigation, it is found that the pre-stressed anchor rope anti slide pile has better seismic performance, but some piles still appear the phenomenon of anchor head failure under the action of earthquake. In order to solve the problem of anchor head failure and improve the seismic performance of anchor anti slide pile, based on the seismic code in our country and structural seismic design code, the optimization design of pre-stressed anchor anti slide pile is carried out and a large shaking table test is carried out to verify it in this paper. The result shows: from the post earthquake horizontal inclination angle, the energy dissipation spring between the anchor head and the pile of anchor can alleviate the anchor head failure in a certain extent. (2) Setting the EPS material behind the pile can reduce the dynamic pressure on the side of the force, and the effect of energy dissipation is related to the input dynamic peak acceleration. And the greater the acceleration of the input, the slower the buffer effect decreases. (3) Through the analysis of experimental and measured results, it can be concluded that the above optimization measures are effective and can provide reference for the design of anchor cable anti slide pile in high intensity earthquake area.