Device And Method For Testing Tensile Resistance Of Multiple-Row Grouped Pillars In Inclined Goaf

    公开(公告)号:US20220244152A1

    公开(公告)日:2022-08-04

    申请号:US17585960

    申请日:2022-01-27

    Abstract: A device and a method for testing tensile resistance of multiple-row grouped pillars in an inclined goaf are provided. The bottoms of stands of the device are connected with a testing machine base, and the tops of the stands of the device are connected with a transverse frame; an upper slideable clamping seat and a lower slideable clamping seat are semi-cylindrical blocks, multiple lower loading jaws that are positioned to have a same central line are arranged on the lower slideable clamping seat, each of the lower loading jaws is opposite to a corresponding one of the upper loading jaws, the lower loading jaws are welded to the lower slideable clamping sea to test the tensile resistance of samples together; the upper part of the upper slideable clamping seat is connected with an upper pressure disk, and the lower slideable clamping seat is connected with a lower pressure disk.

    LOADING SYSTEM AND METHOD FOR HOPKINSON COMPRESSION BAR TEST UNDER WATER-GAS-TEMPERATURE MULTI-FIELD COUPLING ACTION

    公开(公告)号:US20220390340A1

    公开(公告)日:2022-12-08

    申请号:US17835926

    申请日:2022-06-08

    Abstract: A loading system for a Hopkinson pressure bar test under water-gas-temperature multi-field coupling action includes: a sample sealed cabin which includes sealing flanges, Y-shaped and high-temperature resistant sealing rings, and a sealed cabin body; a gas pressure loading device which includes a high-pressure gas tank, a pressure regulating valve, a second barometer, a second high-pressure valve and a first three-way valve connected in sequence; a water pressure loading device which includes an electric pressure test water pump, a water pressure gauge, an accumulator and a one-way valve connected in sequence; a temperature loading device which includes thermocouple heating rods, a temperature display and a thermocouple temperature control circuit board connected in sequence; and a dynamic and static combined loading device which includes an axial pressure loading device, an impact loading device and a Hopkinson pressure bar member.

    VENTILATION METHOD FOR HIGH GAS WORKING FACE BASED ON ALTERNATING INTAKE AND AIR RETURN IN MINE GALLERY

    公开(公告)号:US20250003337A1

    公开(公告)日:2025-01-02

    申请号:US18885086

    申请日:2024-09-13

    Abstract: A ventilation method for a high gas working face based on alternating intake and air return in a mine gallery is provided. In this method, an isolated island working face is divided into several sections along a strike direction. A coal pillar is alternately set as a conventional section and a gas-drainage section. Opposite coal pillars in the two mine galleries within the same section are respectively used as the conventional section and the gas-drainage section. Two mine galleries on both sides of the isolated island working face are alternately used as an intake gallery and a return gallery. The coal pillar at the side of the mine gallery as the return gallery is the gas-drainage section. A gas-drainage hole communicating a goaf is provided in the gas-drainage section, so that gas in the goafs at two sides of the isolated island working face can be extracted alternately.

    FLEXIBLE SANDING DEVICE FOR CYLINDER ROCK SPECIMEN

    公开(公告)号:US20190168357A1

    公开(公告)日:2019-06-06

    申请号:US16208592

    申请日:2018-12-04

    Abstract: A rock sanding device includes a base, a bottom sanding plate, an adjustable connecting rod, an elastic loader, a connector, a side sanding brush, a top sanding plate, an inner rod, a prong and a drill rod. The top of the drill rod is fixedly connected with the rotating shaft of the external water drilling rig and the external water drilling rig has a water inlet joint to introduce water into the drill rod. The inner rod and drill rod are connected and fixed coaxially, and the bottom of the drill rod is symmetrically welded with four prongs. The rock specimen is placed in the center of the side sanding brush. The top sanding plate and the bottom sanding plate are provided in the top side and bottom side of the rock specimen, respectively.

    I-PATTERNED FILLING METHOD FOR INITIAL STAGE OF COAL MINING BASED ON ROOF FRACTURE FEATURE CHARACTERITICS

    公开(公告)号:US20240209734A1

    公开(公告)日:2024-06-27

    申请号:US18595263

    申请日:2024-03-04

    CPC classification number: E21C41/18 E21C2100/00

    Abstract: An I-patterned filling method for an initial stage of coal mining based on roof fracture characteristics is provided. A relationship between an overburden load borne by a main roof and an overhang size is determined based on principle of virtual work and a surgery theory when an overhang distance of the main roof reaches an initial weighting interval to enter a plastic limit state with an advance of a working face to obtain the initial weighting interval. An initial fracturing interval of an immediate roof is obtained in the same way. According to a subsidence law of the main roof in an inverted hip roof form, the filling is performed at a key position around an internal plastic hinge line through I-patterned three-strip filling. Size parameters of the I-pattered filling are designed to prevent the immediate roof and the main roof from being fractured.

    THREE-DIMENSIONAL ANALOG SIMULATION TEST SYSTEM FOR GAS-LIQUID COUNTERCURRENT IN ABANDONED MINE GOAF

    公开(公告)号:US20200088907A1

    公开(公告)日:2020-03-19

    申请号:US16234497

    申请日:2018-12-27

    Abstract: A three-dimensional analog simulation test system for gas-liquid countercurrent in an abandoned mine goaf includes a three-dimensional analog simulation device configured to simulate an analog environment of gas-liquid countercurrent in an abandoned mine goaf, a gas supply system, an automatic water pressure control system and a hydraulic loading system. The three-dimensional analog simulation device includes a reaction frame and a three-dimensional analog simulation chamber. The reaction frame includes a beam, a base and a column for connecting the beam and the base. The three-dimensional analog simulation chamber is arranged inside the reaction frame. The test system can be used to simulate the gas-liquid countercurrent in an abandoned mine goaf so as to study the evolution of water accumulation and gas enrichment in long-term abandonment of closed mines and the migration evolution rules of gas-liquid two-phase in abandoned mines with high gas density.

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