Abstract
The catastrophic evolution of damage fractures and seepage in surrounding rocks under coupled actions significantly impacts the safety of rock mass engineering, such as mining and tunnel construction. To address this, we developed a test platform to observe the spatiotemporal evolution of water inrush from the floor of a mining coal seam. The platform comprises a test bench, servo loading system, water pressure control system, flexible loading system, and intelligent monitoring system. This setup enables flexible loading during overlying rock movement, conducts three-dimensional simulation tests on mining water inrush solid-flow coupling, simulates various crustal stresses, quantitatively monitors water inrush flow and pressure in specific floor areas in real time, and observes the entire process of water inrush crack formation. Using this system and nonhydrophilic similar simulation materials, we conducted experimental simulations on pressurized water inrush in the floor after coal seam mining. We analyzed the visual fracture development process of the floor, the distribution characteristics of water gushing flow in the floor area, and the sudden changes in instant water inrush and stress variation law of the water-resisting layer in the floor. The test results vividly illustrate the catastrophic process of water inrush in the coal seam floor. Our study reveals that, under the combined effects of water, rocks, and stresses, coal mine floor crack expansion exhibits periodic changes. The flow sensor demonstrates a noticeable upward trend during floor crack group expansion, allowing for early warning before water inrush disasters occur by leveraging changes in physical parameters such as flow rates and water pressures. This platform offers a novel and vital tool for addressing rock mechanics challenges in coal mining and for experimental research and testing of mine water inrush mechanisms, prevention, and control.