中文摘要：

对预应力锚索应力分布状态的监测一直是岩土预应力锚固工程中的难题之一，而布里渊光时域反射计（BOTDR）光纤应变传感技术是一项新型光电监测技术，可对光纤及其附着支护表面的轴向应变实现分布式监测，因此研究如何将其应用于岩土工程预应力锚固体系的应力监测具有重要的理论意义与工程价值。分别对1根钢铰线锚索与3根基纶纤维增强复合塑料（AFRP）锚索进行了应力状态监测试验，分布式应变采样点最小间距为5cm。测试结果表明，分布式光纤传感器具有较高的测量精度，光纤传感器与应变计测量结果之间的相对误差小于3．8％。在张拉锚固阶段，1根钢铰线锚索的预应力损失为8．8％，3根AFRP锚索的预应力损失小于6．08％；30d后钢铰线锚索预应力损失为11．1％，AFRP锚索预应力损失小于10．3％。由此可见，将BOTDR分布式光纤传感技术应用于岩土工程预应力锚索的应力分布状态监测具有广阔的前景。

英文摘要：

The monitoring of the stress distribution along prestressed anchorage cables is one of the unsettled issues for prestressed reinforcement in geotechnical engineering. As a novel optical fiber sensing technique, BOTDR （Brillouin optical time domain reflectometer） can be used to measure the distributed strain along an optical fiber bonded to the support structure. Therefore, it is of great theoretical significance and practical value to study how to apply this technique to the monitoring of the stress distribution for the prestressed anchorage cables. A tensile test is carded out for one steel and three AFRP （aramid fiber reinforced plastic） prestressed anchorage cables while the strain distributions of the cables are monitored simultaneously with a sample resolution of 5 cm. The experimental results show that the distributed fiber optic sensing holds a rather high accuracy, with a relative error of the measurement results of no more than 3.8% between the fiber optic sensor and the strain gauge. The instantaneous prestressing loss of steel prestressed anchorage cable is 8.8%, while the instantaneous prestressing loss of AFRP prestressed anchorage cables were under 6.08%. After 30 days, the total prestressing loss of steel prestressed anchorage cable was 11.1%, while the total prestressing loss of AFRP prestressed anchorage cables were under 10.3%. Thus, the conclusion can be drawn herein that BOTDR distributed fiber optic sensing shows considerable applicability in monitoring the stress （strain） state of prestressed anchorage cable in geotechnical engineering.