地层压缩徐变对锚索预应力损失探讨

Discussion on Prestress Loss of Anchor Cable Caused by Ground Compression and Creep

影响锚索预应力损失的因素很多。其中,地层压缩徐变是造成锚索预应力损失的主要因素。研究表明,地层压缩徐变引起锚索预应力损失可分为两个阶段。第一个阶段:在土层厚度未达到限值x时,锚索预应力损失量随着土层厚度增加而增加;第二个阶段:在土层厚度超过限值x后,锚索预应力损失量随着土层厚度增加几乎不变,损失量趋于一个稳定值,支护体系和岩土层达到一个平衡状态。本文以实际工程为依托,基于现场监测数据,对地层压缩徐变引起的锚索预应力损失进行研究,为预应力锚索设计、控制及施工提供一定的参考依据。

There are many factors affecting the prestress loss of anchor cable, among which the compression and creep of stratum is the main factor. The research shows that the prestress loss of anchor cable caused by ground compression and creep can be divided into two stages. The first stage: when the thickness of the soil layer does not reach the limit x, the prestress loss of the anchor cable increases with the increase of the thickness of the soil layer;The second stage: when the thickness of the soil layer exceeds the limit x, the prestress loss of the anchor cable almost remains unchanged with the increase of the thickness of the soil layer, the loss tends to a stable value, and the support system and the rock and soil layer reach a balance state. Based on the project and field monitoring data, the prestress loss of anchor cable caused by stratum compression and creep is studied in this paper, which provides some reference for the design, control and construction of prestressed anchor cable.