Abstract: A method and device for preparing karst caves based on 3D printing technology. The method includes the following steps: determining size of a sample according to test requirements, constructing a 3D karst cave digital model based on three-dimensional karst cave scanning result, and carrying out 3D printing by using alloy to form primary karst cave sample; preparing rock similar material mixture according to proportioning scheme; pouring mixture into sample mold while burying karst cave model into mixture according to position of a karst cave; curing sample together with mold at room temperature until rock similar materials get hardened, removing mold, curing formed karst cave rock sample at constant temperature and constant humidity and then baking or heating same by electrifying heating wire in alloy to form rock sample with hollow karst cave; and filling hollow karst cave with different fillings to form different type of karst cave sample.

Abstract: A sandbox test system and method for a karst aquifer based on tracer-hydraulic tomography inversion, including a visual sandbox apparatus, a karst conduit, a water flow control apparatus, a horizontal well, a data acquisition apparatus, and a data processing apparatus. The visual sandbox apparatus forms a sand layer packing space. The karst conduit is buried in a sand layer. The water flow control apparatus is a constant water head storage tank. A back plate is provided with a horizontal well mounting hole and tracer adding hole. The horizontal well is mounted in each horizontal well mounting hole. A monitoring well is connected to a seepage pressure sensor or an electrical conductivity sensor. A water injection and pumping well is connected to a peristaltic pump. The electrical conductivity sensor, seepage pressure sensor, and peristaltic pump connect to the data acquisition apparatus. The data acquisition apparatus connects to the data processing apparatus.

Abstract: An intelligent lithology identification system and method based on images and spectrum technology. The intelligent lithology identification system includes a rock shape analysis system, an image identification system, a sample processing system, a spectrum analysis system, and a central analysis and control system; wherein the central analysis and control system determines the final lithology of a sample according to the rock identification results from the image identification system and the analysis results from the spectrum analysis system. The technical solution further identifies the content and type of minerals by using spectrum technology, integrates and analyzes the results of spectrum analysis and image identification, and finally gives the lithology of the rock, which greatly improves the accuracy of lithology identification.

Abstract: A laboratory tracer experiment system based on karst conduit medium characteristic inversion, having: a assembly model system of the karst conduit medium; a test bed, configured to support the assembly model system of the karst conduit medium; a water supply system connected to the assembly model system of the karst conduit medium to supply water to the assembly model system of the karst conduit medium; a full-automatic control system for tracer adding connected to the assembly model system of the karst conduit medium to add a prepared tracer solution into the assembly model system of the karst conduit medium; a real-time wireless monitoring system of fluorescent tracer; and a central control system for controlling the full-automatic control system for tracer adding, the water supply system, the real-time wireless monitoring system of fluorescent tracer and the high-definition camera recording system to communicate with the central control system.

Abstract: A laboratory tracer experiment system based on karst conduit medium characteristic inversion, having: a assembly model system of the karst conduit medium; a test bed, configured to support the assembly model system of the karst conduit medium; a water supply system connected to the assembly model system of the karst conduit medium to supply water to the assembly model system of the karst conduit medium; a full-automatic control system for tracer adding connected to the assembly model system of the karst conduit medium to add a prepared tracer solution into the assembly model system of the karst conduit medium; a real-time wireless monitoring system of fluorescent tracer; and a central control system for controlling the full-automatic control system for tracer adding, the water supply system, the real-time wireless monitoring system of fluorescent tracer and the high-definition camera recording system to communicate with the central control system.

Abstract: A whole-process simulation experiment system has: a visualized model system with test samples and serving as a bearing device for the simulation of whole-process seepage of filling-type karst; a controllable support system supporting a visualized model box and controlling fluid seepage direction in the box by changing its inclination angle; a servo loading system controlling water pressure in the test process and providing four different loading modes for the box; a high-speed camera system recording water flow and particle motion in a transparent seepage model box in the seepage failure process; a comprehensive data measuring system 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; and an information analysis and feedback system recording and analyzing the seepage process and the whole seepage failure process in real time to achieve data processing and feedback.

Abstract: An intelligent and flexible steel arch protection device for rockfall and collapse of tunnels, including an arch main body system and a flexible protection system. The arch main body system includes an arched rigid high-strength steel frame and a base. The flexible protection system includes two parallel supporting rods which are oppositely arranged on the steel frame along the circular arc of the arch. Connecting rods are arranged between the two supporting rods at intervals, and the two ends of the connecting rods are fixed to the two supporting rods. The connecting rods are sleeved with guide rods and elastic devices are arranged between the guide rods and the supporting rods. A plurality of rolling shafts vertical to the axial direction of the two-way guide rods and connected with the two-way guide rods are arranged between the adjacent two-way guide rods, and the rolling shafts are sleeved with flexile rollers.

Abstract: An intelligent and flexible steel arch protection device for rockfall and collapse of tunnels, including an arch main body system and a flexible protection system. The arch main body system includes an arched rigid high-strength steel frame and a base. The flexible protection system includes two parallel supporting rods which are oppositely arranged on the steel frame along the circular arc of the arch. Connecting rods are arranged between the two supporting rods at intervals, and the two ends of the connecting rods are fixed to the two supporting rods. The connecting rods are sleeved with guide rods and elastic devices are arranged between the guide rods and the supporting rods. A plurality of rolling shafts vertical to the axial direction of the two-way guide rods and connected with the two-way guide rods are arranged between the adjacent two-way guide rods, and the rolling shafts are sleeved with flexile rollers.

Abstract: A whole-process simulation experiment system has: a visualized model system with test samples and serving as a bearing device for the simulation of whole-process seepage of filling-type karst; a controllable support system supporting a visualized model box and controlling fluid seepage direction in the box by changing its inclination angle; a servo loading system controlling water pressure in the test process and providing four different loading modes for the box; a high-speed camera system recording water flow and particle motion in a transparent seepage model box in the seepage failure process; a comprehensive data measuring system 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; and an information analysis and feedback system recording and analyzing the seepage process and the whole seepage failure process in real time to achieve data processing and feedback.

Abstract: A method and device for preparing karst caves based on 3D printing technology. The method includes the following steps: determining size of a sample according to test requirements, constructing a 3D karst cave digital model based on three-dimensional karst cave scanning result, and carrying out 3D printing by using alloy to form primary karst cave sample; preparing rock similar material mixture according to proportioning scheme; pouring mixture into sample mold while burying karst cave model into mixture according to position of a karst cave; curing sample together with mold at room temperature until rock similar materials get hardened, removing mold, curing formed karst cave rock sample at constant temperature and constant humidity and then baking or heating same by electrifying heating wire in alloy to form rock sample with hollow karst cave; and filling hollow karst cave with different fillings to form different type of karst cave sample.

Abstract: Device and method for measuring true triaxial creep of a geotechnical engineering test block, including a supporting structure; the device includes four confining pressure-plates and upper-and-lower compression-plates forming an enclosed cavity for the test block; confining pressure-plates include two long confining pressure-plates and two short-confining pressure-plates, upper-and-lower compression-plates are rectangular top and bottom steel-plates, two L-shaped long confining pressure-plates bent towards the outer side lapped on two adjacent side faces of the bottom steel-plate, two L-shaped short-confining pressure-plates bent towards the outer side lapped on remaining two-side faces of the bottom steel-plate, and bottom ends of the short-confining pressure-plates are placed on the bottom steel-plate; top ends of long confining pressure-plates lapped on the top steel-plate, and top steel-plate leans against inner side faces of two short-confining pressure-plates; vertically pressure sensors corresponds to

Abstract: Device and method for measuring true triaxial creep of a geotechnical engineering test block, including a supporting structure; the device includes four confining pressure-plates and upper-and-lower compression-plates forming an enclosed cavity for the test block; confining pressure-plates include two long confining pressure-plates and two short-confining pressure-plates, upper-and-lower compression-plates are rectangular top and bottom steel-plates, two L-shaped long confining pressure-plates bent towards the outer side lapped on two adjacent side faces of the bottom steel-plate, two L-shaped short-confining pressure-plates bent towards the outer side lapped on remaining two-side faces of the bottom steel-plate, and bottom ends of the short-confining pressure-plates are placed on the bottom steel-plate; top ends of long confining pressure-plates lapped on the top steel-plate, and top steel-plate leans against inner side faces of two short-confining pressure-plates; vertically pressure sensors corresponds to