Abstract：Fracture width and its variation are of great significance to verify the hydraulic fracture model and to guide the fracturing treatment in oil field. Because that the width of hydraulic fracture is 3–4 magnitude orders smaller than its length or height and the reservoir is deeply buried underground，there is no direct method of measurement regarding the width. The width can only be approximately obtained through the estimation of mathematical models and numerical simulations at present. In order to investigate hydraulic fracture width，the transient changes of the width of concrete fracture were monitored by embedding the strain sensors Fiber Bragg Grating(FBG) along the expected path of fracture propagation during the laboratory hydraulic fracturing experiments. The average velocity of fracture propagation and fracture morphology in different moments of time were also obtained with the multiple FBG strain sensors. The fracture propagation process of hydraulic fracturing was described. The research indicated that the width of hydraulic fracture in laboratory experiment reached micron-scale and the velocity reached 0.1 mm/s scale. The fracture width does not increase monotonously along with the expansion of the hydraulic fracture，but fluctuates within a certain range with the intermittent extension of the hydraulic fracture.
杨 潇，张广清，刘志斌，董昊然，王元元. 压裂过程中水力裂缝动态宽度实验研究[J]. 岩石力学与工程学报, 2017, 36(9): 2232-2237.
YANG Xiao，ZHANG Guangqing，LIU Zhibin，DONG Haoran，WANG Yuanyuan. Experimental research on the variation of fracture width in hydraulic fracturing process. , 2017, 36(9): 2232-2237.
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2017, Vol. 36 
