Experimental system and method for whole-process simulation of seepage failure in filling-type karst media

An adjustable angle experimental system and method for whole-process simulation of seepage failure in filling-type karst media, comprising:

• a visualized model system loaded with test samples and serving as a bearing device to accomplish the simulation of whole-process seepage of filling-type karst;
• a controllable support system for supporting the visualized model system and capable of controlling the seepage direction of fluid in a visualized model box by changing the inclination angle of the visualized model system, the controllable support system comprises fixing hinge supports, hydraulic telescopic rods and triangular hydraulic telescopic frames;
• the fixing hinge supports comprise inlet fixing hinges and outlet fixing hinges which are respectively fixed on the water inlet side and the water outlet side of a seepage model box, the inlet fixing hinges are connected with two sets of triangular hydraulic telescopic frames, the outlet fixing hinges are connected to a base through the hydraulic telescopic rods, and the triangular hydraulic telescopic frames and telescopic rods are controlled to realize 180° rotation of the seepage model box, thereby simulating the seepage failure of a filling medium under different output forms;
• a servo loading system for controlling water pressure in the test process and providing four different loading modes of constant flow, variable flow, constant pressure and variable pressure for the visualized model system;
• a high-speed camera system for recording seepage failure in the visualized model system in the seepage failure process, the high-speed camera system comprises a high-speed camera, a wireless transmission transceiver, an electric slide rail, an automatic lifting rod and a laser range finder;
• the electric slide rail is arranged on a test rack, the high-speed camera, the wireless transmission transceiver and the laser range finder are integrated in a shell and suspended on the electric slide rail through the automatic lifting rod;
• the wireless transmission transceiver communicates with the high-speed camera, the laser range finder and the central processing unit respectively, transmits images photographed by the high-speed camera to the central processing unit in real time, and transmits the distance between the camera and the model box measured by the laser range finder to the central processing unit, and the central processing unit adjusts the electric slide rail and the automatic lifting rod according to the measured distance to maintain a certain distance between the camera and the center of the seepage model box, and automatically rotates and adjusts the high-speed camera to keep the lens parallel to the surface of a seepage container;
• a comprehensive data measuring system for monitoring and recording the change rules of factors including but not limited to seepage pressure, seepage amount and sand gushing amount in the seepage failure process, the comprehensive data measuring system comprises a seepage pressure sensor, a flow recorder, a pressure recorder, a water collector, an automatic weighing measuring instrument and a screening drying device;
• the seepage pressure sensor is embedded in an undisturbed soil sample, the flow recorder and the pressure recorder are fixed on the water inlet pipe to reduce the measurement error caused by uneven loading of the servo loading system, and the seepage pressure, flow and water pressure changes during the test can be transmitted to the central processing unit in real time;
• the water collectors are used for collecting water and solid particles taken out by the seepage failure, and the automatic weighing measuring instrument records an effluent mud gushing weight P1;
• the screening drying device performs standing separation, screening drying and weighing on the water collectors that have completed the mud water collection to obtain a solid weight P2, and a corrected seepage flow Q is further obtained, where:
• Q*=P1/ρwt
• Q=(P1−P2)/ρwt
• wherein ρw is the density of water and t is the time for weighing;
• and
• an information analysis and feedback system for receiving radio signals emitted by the servo loading system, the high-speed camera system and the comprehensive data measuring system, and recording and analyzing the seepage process and the whole seepage failure process in real time to achieve data processing and feedback.