Development Of The Experimental Apparatus For Unsaturated Seepage Flow In Rock Fractures

No matter in engineering construction or in the field of energy mining,problems of seepage flow in fractured rock mass is involved.According to physical characters of seepage flow,it is generally divided into saturated and unsaturated seepage flow.And researches on unsaturated seepage flow and multiphase seepage flow in fractured rock mass are all involved in various application fields of energy and environment,such as rock slope landslide due to rainfall,deep burial of nuclear waste and secondary exploitation of oil and gas,etc.At present,researches on unsaturated seepage flow of fractured rock mass mainly include determination of unsaturated hydraulic parameters and mechanisms of unsaturated seepage flow.But the unsaturated hydraulic parameter is difficult to measure and no formed reliable testing device or testing method are available,so the test accuracy can not meet the actual needs of engineering.Aimed to the shortcomings of the research on experimental apparatus for unsaturated seepage flow in rock fractures and take the research on characters of unsaturated seepage of fractured rock mass as the start,an experimental apparatus for unsaturated seepage flow in rock fractures is designed and developed in this paper,mainly including: 1)the composition framework of the testing device system,the experimental apparatus is composed of seven parts: injection system,model system,confining pressure system,back pressure control system,metering system,data acquisition and processing system and auxiliary system;2)development of each composition sub-system,according to the function and accuracy requirement of experimental apparatus for unsaturated seepage flow in rock fractures,the technical requirements and parameters of each subsystem are studied,and the selection and specification parameters of each subsystem are determined;3)general assembly of the device system.The modular design of the test device system and the flow-based assembly mode of each subsystem are studied,and the assembly principle and mode of the test device system are determined.4)Based on the device mentioned above,a physical model testing method to measure the hydraulic parameters of unsaturated seepage of fractured rock mass is proposed.This device may achieve the real unsaturated seepage of fractured rock mass,its sensor and control system are selected high-accuracy which can meet every technical and accurate indicators that the testing requires,all system is modeling designed and each model is dependent for easy movement,operation and maintenance,it is also conducive to the expansion of subsequent modules.Because the design and production cycle of the test device is longer and the bidding progress is slow,and the fabrication of cracked specimens is not finished.Therefore,the related osmosis test has not been carried out.The inspection device is reasonable and reliable from the perspective of design of test device and test method.