BOTDR technology is used to monitor surface deformation overcoming defects of conventional monitoring means and technology. The authors research on fixation and temperature compensation of fiber in the process of monitoring implementation, emphatically introducing laying means in the Guanjia slope of Longli freeway in Zhejiang Province. Based on characteristics of engineering environment, implanted fixation is used on slope volume. Introducing quasi-distributed monitoring concept, special clamps are used to fix fiber in fixed-point on front slope face. The monitoring results show that tight coated fiber of relatively small outer diameter is suitable for implanted fixation to ensure sync coordinate deformation and sensitivity of fiber is improved because of smaller sheath effects. Big outer diameter is suitable for fixed-point. When temperature field changes a little, temperature compensation could be neglected. In contrary, it could be carried out by selecting similar monitoring environment and laying relaxed fiber to measure temperature changes. At the end it is discussed about fiber laying measures improvement and temperature compensation means.%针对普通监测手段和技术应用上的不足.采用BOTDR技术监测坡体表面变形发展.分析了监测实施过程中光纤传感器的固定及温度补偿问题,介绍了BOTDR在浙江省龙丽高速公路官家滑坡中的铺设手段.根据官家滑坡的工程环境特点,在坡体上采用植入式固定方式;前缘坡面布设光纤时,引入准分布式监测理念,使用专用夹具定点固定光纤.现场监测结果表明:植入式固定方式,宜选用外径较小的紧套光纤,能使其较好地保持同步协调变形,且光纤因护套影响小而灵敏性较高;定点固定方式,易选用外径较大的光纤,适宜于坡面监测环境.植入式固定方式.若坡体内温度场变化较小,可不进行温度补偿;若坡面温度变化较大,可选取与监测环境温度场相似区布设松套光纤进行温度补偿.对监测过程中实施光纤的固定及温度补偿手段进行了改进讨论.
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