203 results about "Support pressure" patented technology

The invention provides a small-bending-radius pipe push-bending device and a using method thereof.The small-bending-radius pipe push-bending device comprises an upper supporting plate, a push rod, a hydraulic pressurizing pipe, a guide sleeve, a push-bending mold, a sealing joint, a sealing ring, a rubber ball, a pressure sensor, a hydraulic pushing cylinder, a movable ball joint and a hydraulic pressurizer. The using method comprises the following steps that firstly, a straight pipe needing to be machined is installed on the inner side of the push-bending mold; the guide rod is attached to the guide sleeve; a plurality of rubber balls are filled in the inner cavity of the straight pipe; a gap of an inner cavity of the straight pipe is filled through the hydraulic pressurizer; starting the press to apply downward pressure to the push rod; the liquid filling pressure is set to pressurize and support the interior of the pipe, and the pipe begins to be bent and formed along with descending of the push rod; and after 90-degree bending forming is completed, the liquid filling pressure is gradually increased for pressurization shaping. By adopting the mode of filling gaps with rubber balls and hydraulic pressure, the supporting pressure in the pipe is improved; and by adopting a differential friction form, the length of a linear section is increased, and meanwhile uniform stress in the bending process is achieved.

The invention relates to the technical field of shield tunnel engineering, and discloses a backward shield tunnel face support pressure calculation method suitable for high-water-pressure permeable stratum shield in-ground butt joint, which comprises the following steps of: establishing a shield in-ground butt joint balance relation in combination with mechanical equilibrium analysis in a shield in-ground butt joint process; calculating the penetration resistance of the cutter at different tunneling speeds based on a butt joint adjacent stratum penetration resistance test; the supporting pressure of the backward shield tunnel face is calculated, and tunneling construction is guided through the supporting pressure of the backward shield tunnel face at different tunneling speeds. According to the method, the problem of parameter setting in the proximity tunneling process of the following shield can be effectively solved, the balance formula has universality for similar shield butt joint projects, the corresponding relation between the penetration resistance and the tunneling speed of the butt joint position can be truly reflected through the penetration resistance test of the near ground layer, and the method has the advantages of being high in practicability and the like. And the set value of the supporting pressure of the tunnel face of the subsequent shield is obtained, and a theoretical basis is provided for setting tunneling parameters of the subsequent shield.

The invention discloses a tunnel trolley supporting system and method intelligently adapting to geological conditions, and belongs to the technical field of tunnel safety supporting. The device comprises a supporting truss, a rigid supporting mechanism and a flexible supporting mechanism. Wherein the flexible supporting mechanism comprises an air bag which is used for preliminarily supporting the surrounding rock of the tunnel; the rigid supporting mechanism comprises a mounting frame, a plurality of air chambers are arranged in the mounting frame, and adjusting assemblies are arranged in the air chambers; the adjusting assembly comprises a piston plate and a piston rod located on the piston plate, and the free end of the piston rod penetrates through the mounting frame, then extends into the air bag and is connected with a supporting plate. The supporting plates are used for carrying out secondary supporting on the tunnel surrounding rock from the interior of the air bag, the supporting pressure of each supporting plate can be adjusted through the inflation pressure in the corresponding air chamber so as to adapt to different geological conditions, good self-adaptive capacity is achieved, and dynamic distribution of the surrounding rock pressure is achieved.

A method for determining an abnormal trend in the supporting of a support of a fully mechanized mining face. The method comprises: acquiring first pressure monitoring data of all hydraulic supports at an initial stage of a stoping process of a fully mechanized mining face, and second pressure monitoring data of all the hydraulic supports during a routine stoping process of the fully mechanized mining face; determining first working cycle pressure data of each hydraulic support at the initial stage of the stoping process, and second working cycle pressure data of each hydraulic support during the routine stoping process; determining reference similarity and real-time similarity of each hydraulic support; and determining an abnormal state of supporting pressure of each hydraulic support.

A pressure vessel support apparatus includes a first side member configured to be coupled to an object, a second side member spaced from the first side member, and a cross-frame portion connecting the first side member and the second side member and supporting a pressure vessel between the first side member and the second side member, obtaining an advantageous effect of simplifying a structure and improving spatial utilization and a degree of design freedom.

The invention relates to the technical field of welding machines, and discloses a high-reliability and high-bearing welding machine for drill rod spring production, which comprises a welding table, a baffle plate is fixedly connected to the top of the welding table, a clamping device is arranged at the top of the welding table, and a discharging device is arranged on the inner wall of the clamping device. When springs start to be welded, the drill rod springs are placed on the top of a fixing plate, a sliding rod moves to drive an arc-shaped plate to move, and therefore the surfaces of the drill rod springs can be clamped; according to the drill rod spring welding device, the supporting pressure of the fixing plate can be reduced in the welding process of a drill rod spring, then the stability of the drill rod spring in the welding process can be improved, the surface of the spring can be wrapped through the inner arc face of the arc-shaped plate, and the stability of the device is further improved; and the firmness degree of the drill rod spring in the welding process can be increased.

A multi-hydraulic support load model training method and a multi-hydraulic support load prediction method. The multi-hydraulic support load model training method comprises: acquiring leg pressure data, top beam pitch angle data, top beam roll angle data, coal mining machine cutting position data, coal mining machine traction speed data, and an initial hydraulic support pressure regression prediction model; preprocessing the data to generate a dataset; generating a training dataset and a verification dataset on the basis of the dataset; and training the initial hydraulic support pressure regression prediction model on the basis of the training dataset and the verification dataset, so as to generate a target hydraulic support pressure regression prediction model of a target fully-mechanized coal mining face hydraulic support. By taking into account four dimensions of the top beam pitch angle data, the top beam roll angle data, the coal mining machine cutting position data, and the coal mining machine traction speed data, the target hydraulic support pressure regression prediction model is established and generated by training, so that the support pressure prediction effect can be improved; in addition, by means of model prediction, the prediction efficiency can be improved, and the prediction costs can be reduced.

The invention belongs to the technical field of tunnel construction, and relates to a longitudinal slope non-uniform rectangular tunnel surface support pressure calculation method, which comprises the following steps: adjusting an included angle between a wedge and a working surface in a six-block silo-wedge model based on the gradient of a tunnel to be tunneled to obtain an upslope optimization model; on the basis of a stress system of the rectangular pyramid wedge-shaped body and the triangular prism wedge-shaped body in the tunneling process, a mechanical equation of the rectangular pyramid wedge-shaped body in the tunneling process and a mechanical equation of the triangular prism wedge-shaped body in the tunneling process are constructed, and then a critical support pressure control equation representing the working face stability in the tunneling process is obtained; constructing a support pressure equation of the soil cabin partition plate by utilizing a stress balance principle of a soil cabin soil body along a tunneling slope direction; and calculating the supporting pressure of the soil cabin partition plate in real time by utilizing a supporting pressure equation of the soil cabin partition plate based on the tunneling gradient, the burial depth, the working face width, the working face height and the wedge-shaped body sliding face inclination angle in the tunneling process so as to judge whether the working face is stable in the tunneling process of the to-be-tunneled tunnel.

Disclosed in the present disclosure is a supporting bolt, a cantilever supporting structure and a conducting device. The supporting bolt includes a locking screw, a support screw sleeve, and an elastic supporting member. The locking screw is fixedly connected the pressure receiving structure. The support screw sleeve is fixedly connected the pressure applying structure and is slidably disposed on an outer surface of the locking screw along a direction of the central axis within a sliding range. The elastic supporting member includes a first elastic member, a first end of the first elastic member is compressed against the support screw sleeve, and a second end of the first elastic member is compressed against the pressure receiving structure, the first elastic member has an elastic force along the pressure receiving structure towards the pressure applying structure to support the pressure applying structure.

The application discloses a method for determining support pressure of a tunnel face in opposite excavation, and comprises the following steps: S1, establishing an active failure mode of a soil body of the tunnel face in opposite excavation, wherein the active failure mode comprises a logarithmic spiral wedge-shaped sliding surface failure body in front of two tunnel faces and a semi-elliptical collapse body above and in front of the two tunnel faces; S2, obtaining a moment balance equation of the logarithmic spiral wedge-shaped sliding surface failure body and the semi-elliptical collapse body based on a limit equilibrium method; and S3, reversely deducing a critical support force P of the tunnel face in opposite excavation according to the moment balance equation. The active failure mode and the critical support force P obtained by calculation are reliable and reasonable.

The utility model provides a kind of inside and outside pressure balancing device of honeycomb block uniform impregnation, it is related to the technical field of honeycomb block production device, to solve the problem that atmospheric pressure impregnation: glue solution can only pass through surface penetration vacuum impregnation: although it can accelerate penetration, but honeycomb internal air cannot be discharged in time;Including impregnation carrier frame, bearing support frame, closed carrier cover and bearing support;The impregnation carrier frame bottom is fixedly provided with support bottom frame;The bearing support frame is fixedly set in the impregnation carrier frame top, and the inboard of bearing support frame is fixedly provided with positioning support;The closed carrier cover is set in the bearing support frame top;The bearing support is fixedly set in the installation base bottom, and the bottom of bearing support is fixedly provided with closed pressure block;Installation side frame moves by the support of hydraulic prop supporting pressure-boosting support plate, so that pressure-boosting support plate extrudes colloid carried by impregnation support frame, so that colloid uniformly applies pressure to the whole inside and outside of honeycomb block for impregnation, and pressure guide branch pipe guides the gas generated by extruding the inboard of impregnation carrier frame.

The invention discloses an advanced small pilot tunnel construction method for a high ground stress soft rock tunnel, belongs to the technical field of tunnel engineering construction, and adopts an excavation mode of combining a micro-step with a small pilot tunnel method and a support measure of combining a composite lining structure with a retractable U-shaped steel frame for temporary support. When crossing through a high-ground-stress soft rock stratum, by constructing the advanced small pilot tunnel, the effects of geological pre-judgment, risk pre-prevention and control, stress release in advance, support pressure relief, disturbance reduction and surrounding rock loosening circle reduction can be achieved. The surrounding rock deformation after the main tunnel is excavated is effectively reduced, so that the high-crustal-stress soft rock tunnel is efficiently and safely constructed.

The utility model relates to the technical field of hot runner molds, in particular to an ejection mechanism for a hot runner mold, which mainly comprises a supporting bottom plate, a lower mold block arranged at the top end of the supporting bottom plate, an upper mold block arranged at the top end of the lower mold block, a connecting top plate arranged at the top end of the upper mold block, and an ejection adjusting component arranged at the top end of the lower mold block. The ejection adjusting assembly comprises a telescopic ejector rod, an elastic connecting piece is arranged on the inner side of the telescopic ejector rod, an adjusting sliding block is arranged at the top end of the telescopic ejector rod, and a fool-proof ejector block is arranged on the inner side of the adjusting sliding block. According to the ejection mechanism for the hot runner mold, the lower mold block and the upper mold block are separated through movement of the telescopic ejection rod, buffering connection is carried out through the elastic connecting piece in the moving process, the protection performance is improved, the adjusting sliding block and the positioning block on the inner side are clamped and positioned through the fool-proof ejection block, and the safety is improved. The supporting pressure of the telescopic ejector rod can be shared in the using process, abrasion of the telescopic ejector rod is reduced, and the using efficiency of the mold is ensured.

The invention relates to the technical field of oil and gas drilling, in particular to a rotating speed controlled drilling tool clutch tool, and aims to solve the problem of high supporting pressure caused by non-rotation of a drilling rod in current drilling operation. The invention provides a rotating speed controlled drilling tool clutch tool. The rotating speed controlled drilling tool clutch tool comprises an upper connector, a central pipe, a transmission block assembly, a spline housing, a middle connector, a lower connector, a bearing pack and a transmission mandrel. The upper joint, the spline housing, the middle joint and the lower joint are in coaxial threaded connection from top to bottom; an arc block extends out of the upper end of the spline sleeve and extends into the circular groove, and a first spline groove and a second spline groove are formed in the spline sleeve; the bearing set is arranged between the lower connector and the transmission mandrel, and the lower connector can rotate relative to the transmission mandrel. The upper portion of the first spline rod can extend into the first spline groove, the lower portion of the first spline rod can extend into the third spline groove, the upper portion of the second spline rod 3021 can extend into the second spline groove, and the lower portion of the second spline rod 3021 can extend into the fourth spline groove.

The invention discloses an axial vibrator suitable for backing pressure release of a drill column of a large-displacement well, relates to the technical field of drilling operation, and adopts an electromagnetic pulse type axial vibration mode formed by an electromagnetic principle. On the basis, a transmission structure in the whole reciprocating impact process is optimized into a front rod, a middle rod and a rear rod, and the specific process is as follows: an outer bent spring frame and an inner bent spring frame are obtained by optimizing again on the basis of the axial impact process in cooperation with the flowing direction of drilling fluid, and the outer bent spring frame is matched with the axial impact action to carry out adaptive deviation; the invention aims to reduce the dispersion degree of impact force in the reciprocating impact action and ensure that the impact direction is maintained in the axial direction, and the inner bent spring frame is used for maintaining the transmission direction of the impact force, ensuring the deflection degree of the middle rod relative to the rear rod and ensuring that the whole axial vibration process is maintained in the direction parallel to the length direction of a drilling tool, and is particularly used for stabilizing the drilling pressure.

The utility model discloses a kind of bushing press fitting machine, including machine body, rotating limiting mechanism being arranged at the one side of machine body and top pressure subassembly being arranged at the other side of machine body, the rotating limiting mechanism includes the fixed plate being connected with the output end of step motor and the limiting rod for limiting fixed plate offset, detachably provided with pressure assembly on the fixed plate, the pressure assembly includes guide sleeve and the pressing plate being arranged on guide sleeve, lifting assembly is provided at the position below corresponding top pressure subassembly on the machine body, the lifting assembly includes the bottom plate lifted by push block drive.This utility model sets rotating limiting mechanism to position rotation to the position below top pressure subassembly, and top pressure subassembly promotes pressure assembly to press bushing into workpiece, among them, lifting assembly is also provided, to make bottom plate support pressure assembly in press fitting process, to improve press fitting efficiency.

The utility model relates to pressure vessel transportation technical field, specifically disclose a vertical pressure vessel transportation support, including the trolley, the trolley includes the bracket, and one side of bracket is connected with the bottom plate, and the other side of bracket is equipped with the wheel, and the upper end of bracket is connected with the handle, the inside of bracket is equipped with the support mechanism of supporting pressure vessel, the both sides of bottom plate are equipped with the side guard frame, and the front end of side guard frame is connected with the guard door, the upper portion of support mechanism is equipped with the locating rack, the locating rack includes the first locating rod and the second locating rod of V type structure, the first locating rod and the second locating rod are connected through the first threaded rod between and the interval is adjustable, and the first locating rod is connected with the second locating rod all with the side guard frame, and the first locating rod and the second locating rod sleeve are positioned to the outside of pressure vessel, the utility model discloses the stability of pressure vessel in the transportation process is ensured through support mechanism and locating rack, and the safe use is ensured.

The utility model discloses a combined top beam hydraulic support, and relates to the technical field of hydraulic supports. Comprising a base, driving mechanisms are fixedly installed between the front inner wall and the rear inner wall of the base and close to the left and right positions, rolling wheels are fixedly installed at the four corners of the lower surface of each driving mechanism in a rectangular shape, and first rectangular openings are formed in the positions, corresponding to the rolling wheels, of the lower side wall of the base; a front beam is hinged to the left side face of the top beam, pressure detection mechanisms are arranged in the top beam and the front beam, and supporting mechanisms are arranged on the upper surfaces of the pressure detection mechanisms. According to the hydraulic support, the moving function of the hydraulic support is added, the hydraulic support can be conveniently moved, the moving process is more stable, meanwhile, the supporting pressure of the hydraulic support can be monitored, the problem of overlarge pressure can be solved in time, use is safer, the supporting position can be adjusted, and supporting is more convenient.

The utility model discloses a powder pressing hammer which comprises a hammer head used for flattening powder and a pressing mechanism, the hammer head is provided with a main rod used for installing the pressing mechanism, and a movable channel is arranged in the main rod. The downward pressing mechanism comprises a pressing rod internally provided with an impact channel, an impact piece arranged in the impact channel, an impact spring used for driving the impact piece to press downwards and a reset buffer spring used for supporting the pressing rod, and a limiting through hole communicating with the impact channel is formed in the side wall of the pressing rod. A movable limiting piece used for preventing the impact piece from moving downwards is arranged in the limiting through hole, and the movable limiting piece moves back and forth in the movable channel and the impact channel through the limiting through hole. And an impact control part for jacking the movable limiting piece into the impact channel is arranged in the movable channel. By means of the coffee powder pressing device, the powder pressing effect that coffee powder is evenly scattered and punched in sequence can be achieved.

The utility model discloses a vibration stirring device for processing lubricating powder for railway, which comprises a support ring frame, the upper surface of the support ring frame is provided with elastic support pressure springs, the elastic support pressure springs are welded and fixed on the upper surfaces of four corners of the support ring frame, the upper surfaces of the elastic support pressure springs are fixedly welded with a support plate body, and the support plate body is fixedly welded on the upper surface of the support ring frame. A stirring spherical shell is fixedly connected to the surface of the inner side of the supporting plate body, a vibrator is fixedly connected to the upper surface of the supporting plate body, a motor is fixedly connected to the surface of the upper end of the stirring spherical shell, a driving rod piece is fixedly connected to the outer surface of a driving shaft of the motor, and spiral blades are fixed to the outer surface of the lower end of the driving rod piece. A spherical shell structure is adopted for stirring, the interior is smooth, downward discharging is facilitated, discharging is convenient, inner and outer double-layer stirring is achieved during stirring, stirring and scattering are uniform and comprehensive, and stirring uniformity is improved.

The invention discloses a novel sealing structure for adjusting the internal support pressure of a water stop rubber seal of a gate through gas-liquid two-phase conversion, which is characterized in that at least one axial cavity is arranged on a sealing strip, the cavity can be distorted, deformed and self-recovered, the cavity is filled with a volatile medium, the cavity is kept in an expansion state, the filling volume proportion of the medium is 50 + / -5%, and the filling volume proportion of the medium is 50 + / -5%. The sealing structure is provided with a cavity and is filled with a gas-phase medium and a liquid-phase medium, the filling volume of the liquid-phase medium is about half of the volume of the cavity, and the remaining cavity space is filled with the gas-phase medium, so that the cavity is kept in an expanded state. The gas-phase medium is guaranteed to be sufficient through existence of the liquid-phase medium, pressure and temperature changes are compensated, it is guaranteed that the cavity is in an expansion state all the time, through gas-liquid conversion, when the cavity is compressed, deformation pressure of volume reduction of part of the space is shared through gas-liquid conversion, certain pressure is still kept to support deformation of the cavity, and acute-angle breakage of the cavity is reduced.

The application discloses a method for determining support pressure of a tunnel face in opposite excavation, and comprises the following steps: S1, establishing an active failure mode of a soil body of the tunnel face in opposite excavation, wherein the active failure mode comprises a logarithmic spiral wedge-shaped sliding surface failure body in front of two tunnel faces and a columnar collapse body above the two tunnel faces; S2, determining a geometric relationship of the active failure mode, and obtaining a moment balance equation of the logarithmic spiral wedge-shaped sliding surface failure body and the columnar collapse body based on a limit equilibrium method; and S3, reversely deducing and calculating a critical support force P of the tunnel face in opposite excavation according to the moment balance equation. The active failure mode and the critical support force P obtained by calculation are reliable and reasonable.

The invention discloses a small-clear-distance tunnel backward shield excavation face support pressure determining method which comprises the steps that soil parameters are collected, data comprise soil cohesion and internal friction angle data, geometric parameters of tunnel diameter, burial depth and clear distance are recorded, numerical model construction is conducted through the collected parameters, numerical models of a tunnel and surrounding soil are constructed, and the tunnel backward shield excavation face support pressure is determined. Meanwhile, analyzing the stress state, stratum type and address characteristic data of the soil body by utilizing a numerical model, simulating an excavation process after data analysis is completed, simulating a propelling process of a shield tunneling machine, gradually removing the soil body, applying corresponding support pressure, and recording the support pressure, soil body deformation and displacement data at different time points; the method is based on numerical simulation and machine learning methods, the multi-factor coupling influence is systematically considered, blindness of an experience method is avoided, the established relational expression covers a wide parameter change range, and the method can be suitable for small-clear-distance projects with different geological conditions and tunnel design parameters.

The invention provides an automobile crane supporting pressure calculation method which mainly comprises the following steps: equivalently transferring all loads of a crane to a point O based on a static load test to obtain a test condition self-weight load standard value Nz and a test condition vertical load standard value Ne which act on the point O, a torque standard value Me generated by the test loads and a test condition total torque standard value Ms; the stabilizing moment Mw is caused by the dead load, and when the total moment standard value Ms is calculated, the landing leg on the light load side keeps the gravity of the crane, namely 15% of the dead load standard value Nz. According to the method, the traditional calculation method is improved, and the factor that the light load side supporting leg is influenced by the gravity of the crane during the static load test is considered, so that the pressure calculation result is more accurate.

The application provides a caving mechanism control system based on working resistance, and relates to the technical field of underground coal mining, wherein the system comprises: a mine pressure monitoring device for monitoring the working resistance of a hydraulic support column; an intelligent control device for acquiring a standard pressure drop value of a standard working resistance curve of a rear row column, and acquiring a hydraulic support pressure drop value in real time through the mine pressure monitoring device; when the pressure drop value reaches the standard pressure drop value, a caving mechanism return instruction is sent to the hydraulic support; and an electro-hydraulic control device for controlling the hydraulic support and the caving mechanism thereof to close the caving opening according to the return instruction, and completing the caving action. The application enables the hydraulic support to close the caving opening in time to complete the caving action through the caving mechanism return instruction, thereby improving the top coal recovery rate, reducing the mixed gangue rate, and improving the production capacity and the degree of automation.

The present invention discloses an explosion-proof electrical cabinet which is convenient for maintenance, and belongs to the technical field of electrical cabinets. The cabinet comprises a hollow support pressure relief box, wherein a limited position mounting metal frame is arranged on the upper surface of the hollow support pressure relief box, the limited position mounting metal frame is fixedly connected to the hollow support pressure relief box, a plurality of third wire threading pressure relief holes are arranged at intervals on the side surfaces of the limited position mounting metal frame, a pressure relief reinforcement pipe is arranged on the top of the hollow support pressure relief box, the pressure relief reinforcement pipe penetrates through the top wall of the hollow support pressure relief box, the pressure relief reinforcement pipe is fixedly connected to the hollow support pressure relief box, and the pressure relief reinforcement pipe is fixedly connected to the limited position mounting metal frame; through the mutual cooperation of multiple structures, a user can realize instant disassembly of the electrical cabinet, so as to facilitate the user to repair the electrical cabinet, saving time and effort; secondly, through the linkage cooperation of multiple structures, a user can realize rapid assembly of the electrical cabinet, thereby making the use of the electrical cabinet more convenient.

The utility model discloses a cross balance beam storage support for a nuclear power ring crane, and belongs to the technical field of storage racks, a base is a cuboid, a lifting ring matched with a lifting appliance is fixedly mounted in the center of the base, supports are fixedly mounted on the lifting ring in a bilateral symmetry manner, U-shaped holes are formed in the top ends of the two supports in the same direction, and the U-shaped holes are communicated with the lifting appliance. And a buffer device is arranged in the bracket below the U-shaped hole. According to the utility model, the U-shaped spring block is pushed by the buffer device, so that the U-shaped spring block is propped against the cross beam, and the elastic force of the spring is used for counteracting part of the weight of the lifting appliance to share the pressure of the bracket; the lifting ring is in contact with the lifting appliance, so that the pressure of the bracket is further shared, and the pressure distribution of the bracket is more uniform; by utilizing the hoisting device, the hoisting tool and the bracket can be conveniently matched for hoisting, so that the bracket is more flexible to move.

The utility model relates to the technical field of coal mine filling and plugging, in particular to a lifting and fixing device for coal mine filling and plugging, which comprises a base, a box body is arranged above the base, tracks are arranged on two sides of the lower surface of the base, a first lifting device is arranged between every two adjacent tracks, and a support is further arranged on the side face of the box body. And a second lifting device is arranged at the bottom of the bracket. The first lifting device is arranged in the middle of the lower surface of the base, and the circular connecting table and the support are arranged below the first lifting device, so that the stability of the filling and plugging device in the plugging process can be guaranteed, and the stability of the filling and plugging device can be improved; the support can be supported and protected, the supporting pressure of the plugging and filling equipment can be effectively relieved through cooperation with the first lifting device, the stability of the equipment can be enhanced, and the safety coefficient of the equipment is improved.

The invention provides a karst tunnel excavation support pressure reliability design method based on threshold gradient. According to the method, aiming at three random variables in an HB constitutive model, firstly, center composite sampling is carried out in a standard normal space to obtain seven test points, coordinates of the test points are converted into an original parameter space, a failure threshold value of each test point is obtained through calculation by establishing a numerical model, then a secondary response surface agent model without cross terms is established, and the failure threshold value of each test point is calculated. And establishing a tunnel face support force dominant threshold function by solving a linear equation set and determining seven coefficients of the proxy model, on this basis, proposing a standard normal space target reliability isoline checking point iteration method, performing checking point iteration on a sphere with the radius being the target reliability, and updating checking points in a gradient manner by adopting the threshold function. And calculating the collapse load of the design point during iterative convergence, so that the collapse load meets the requirement of a target reliable index. According to the method, the design complexity is reduced, and the design efficiency is improved.

Gas spring (100) comprising a. a pressure chamber filled with a gas in a pressure tube (110); b. a working piston (120) which is movable in the pressure chamber along a stroke axis (HA), c. a piston rod (140) attached to the working piston (120) and guided out of the pressure tube (110) along the stroke axis (HA) by a guide-sealing device (130), and d. a separating piston (150) arranged on the side of the working piston (120) facing away from the guide-sealing device (130) and displaceable along the stroke axis (HA) relative to the pressure tube (110) and relative to the working piston (120), e. wherein the separating piston (150) divides the pressure chamber gas-tight into a working chamber (112) containing the working piston (120) and a support chamber (113), characterized in that f. the gas spring (100) comprises a holding device (160), g. wherein the holding device (160) holds the separating piston (150) in a fixed position on the pressure tube (110) as long as a positive pressure difference between a support pressure of the gas in the support chamber (113) and a working pressure of the gas in the working chamber (112) is less than a predefined switching differential, and h. wherein the holding device (160) is designed so that a switching force caused by the pressure difference acting on the separating piston (150) releases the separating piston (150) from the pressure tube (110) as soon as the pressure difference reaches the switching difference, so that the separating piston (150) is movable onto the working piston (120).