索体腐蚀对锚索结构锚固性能的影响

发布时间：2018-08-16 15:34

【摘要】：为了给侵蚀环境下锚索结构长期锚固性能评估与设计提供参考,考虑锚固受力时的围岩约束因素,设计制作了外包钢管圆柱形素水泥浆中置钢绞线短黏结试件模拟锚索结构单元,采用直流通电方式使钢绞线实现5%、10%和15%三个不同程度的腐蚀率,然后通过静力拔出试验观察锚固受力过程,获取黏结-滑移曲线,定义锚固特征参数,分析腐蚀对锚固性能的影响规律,建立黏结-滑移本构关系经验模型。结果表明:围岩约束显著提高了锚固强度和延性性能;腐蚀程度对黏结-滑移曲线特征产生很大影响;与无腐蚀锚索相比,当腐蚀率小于15%时,腐蚀锚索锚固强度最大可提高至2.5倍左右,但正常工作刚度和延性指数则可分别降低至12%和0.32%左右。
[Abstract]:In order to provide a reference for the long-term anchoring performance evaluation and design of anchor cable structure under erosion environment, the surrounding rock constraint factors of anchoring force are considered. In this paper, the simulated anchor cable structure unit is designed and manufactured for the short bonding test piece of steel strand in cylindrical cement slurry, and the corrosion rate of 5% 10% and 15% can be achieved by using DC electrification mode. Then, through static pull-out test, the stress process of anchoring is observed, the cement-slip curve is obtained, the characteristic parameters of anchoring are defined, the influence of corrosion on anchoring performance is analyzed, and an empirical model of cement-slip constitutive relationship is established. The results show that the anchoring strength and ductility of the surrounding rock are significantly improved, the corrosion degree has a great influence on the characteristics of the cement-slip curve, and the corrosion rate is less than 15 when compared with the non-corrosive anchor cable. The maximum anchoring strength of corrosion anchor cable can be increased to about 2.5 times, but the normal working stiffness and ductility index can be reduced to 12% and 0.32% respectively.
【作者单位】：中国矿业大学江苏省土木工程环境灾变与结构可靠性重点实验室;中国矿业大学深部岩土力学与地下工程国家重点实验室;天元建设集团有限公司;
【基金】：国家自然科学基金项目(51178454) 江苏省自然科学基金项目(BK2011222)
【分类号】：TU476

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