为进一步开发煤炭资源而采用多煤层开采的方式，随着累计采厚的增大，多煤层开采过程中主关键层经历多次采动影响，主关键层结构的破坏将引起采场上覆岩层整体的变形破坏，同时决定上位岩层整体的结构形态。因此本文从多煤层开采过程中主关键层的受力变形出发，采用理论分析、数值模拟和相似材料模型实验相结合的研究方法，以乌苏海则井田2、3号煤层相距46.9m且覆岩中含有主关键层为工程背景，利用光纤传感技术对多煤层开过程中覆岩结构演化特征进行研究。 计算并判别出上覆岩层中主关键层的位置，通过分析2、3号煤层顶底板岩性计算得出两层煤开采后导水裂隙带发育的最大高度，并建立了两层煤开采覆岩结构演化模型。采用FLAC3D软件对2、3号煤层开采过程中覆岩应力状态及塑性区的分布特征进行模拟。将FBG和PPP-BOTDA光纤传感技术联合应用于相似材料模型实验中，模型实验中首次采用温度补偿方法对FBG和BOTDA测试系统进行温度补偿，合理解决了温度变化对实验测试精度的影响；采用铁砂加载方式代替铁砖加载，有效控制了加载的准确性及连续性；此外，采用加热法对模型内部的光纤进行了定位，保证了光纤测试的有效性。在2m模型内埋设4根传感光纤和2个光纤光栅应变传感器，对多煤层开采主关键层由弯曲下沉发育至断裂过程中的应力应变进行感测。 研究表明，2号煤层开采后主关键层及上位岩层处于弯曲下沉带中，连续变形未破断的主关键层阻碍裂隙向上位岩层发展；3号煤层开采后主关键层破断导致上覆岩层整体处于断裂带中，裂隙向上位岩层蔓延，导水裂隙带发育至洛河组含水层。模型实验中需要采用温度补偿方法对FBG光栅和BOTDA光纤测试结果进行补偿，铁砂加载方式相对铁砖加载更具有准确性，PPP-BOTDA分布式光纤感测技术能很好的监测岩层整体的运动规律和发展趋势，FBG传感器可以监测岩层关键点的运动情况，实现了对覆岩主关键层结构演化过程中整体及局部的实时监测，为乌苏海则井田安全生产提供依据。

For further development and utilization of coal resources and the use of multi-coal seam mining. As the increase of the cumulative mining height, the main key stratum has been influenced many times in the process of multi-coal seam mining has many influences. The movement of overlying strata of the main key stratum play a decisive role until the surface of all layers , and the damage of main key stratum affect the deformation and failure of overburdens directly in mining field.At the same time ,it decided the "three zones" development height. This study from the point of main key stratum in coal mining process of deformation,and by means of theoretical analysis, numerical simulation and physical model test .Combining with these methods, the study aimed at overburdens movement evolution of the multi-coal seam in Wusu Hai in the process of mining. A systematic calculation of the position of the hard rock strata, and identify the main key position in overlying strata. Through the analysis of the lithology of roof and floor at 2# and 3# coal seam , calculated the maximum height of water flowing fractured zone in the mining of 2# and 3# coal seam. The distribution characteristics of stress state and plastic zone of overlying strata are calculated by using FLAC3D software in the process of 2# and 3# coal seam mining. The combination of FBG and PPP-BOTDA optical fiber sensing technology are applied to similar material model experiment ,and the temperature compensation method is used to compensate the temperature of FBG and BOTDA for the first time in the physical model test, which solves the influence of measuring accuracy that temperature changes on the test. The method of loading by iron-sand instead of iron brick control the accuracy and continuity of loading effectively. In addition, the heating method is used to locate the optical fiber in the model, which ensures the efficiency of the optical fiber testing. Four sensing fibers and two fiber Bragg grating strain sensors were embedded in the 2 m plane stress physical model for studying the change of stress and strain of the main key stratum in the upper strata of the upper strata of the multi seam mining. The research shows that after the 2 #coal seam mining, the main key stratum is not broken, which hinders the fracture spread to the upper layer, and the upper layer of the main key stratum is in the curved sinking zone. After the 3# coal seam mining, the main key stratum is broken, and the fracture of the main key stratum causes the fracture to spread to the upper layer, and the water flowing fractured zone developed to the Luohe aquifer. The temperature compensation method should be used to compensate the FBG grating test and the BOTDA fiber test in the model test.The iron-sand loading has more accuracy relative to iron brick ,and PPP-BOTDA distributed optical fiber sensing technology can monitor the movement of overburdens and the trend of development .FBG sensors can monitor the key-points of the rock movement .This experiment realizes the real-time monitoring of key-strata, which including the process of continuous changing into a semi continuous the whole and the part of, and provide the basis for the safety production of Wusu Hai.