Construction technology of pouring of double-layer shaft wall of trestle template trolley and frozen inclined shaft

Abstract

This invention discloses a trestle-type formwork trolley and a construction process for pouring double-layer well walls in a frozen inclined shaft. The trestle-type formwork trolley includes a full-ring formwork gantry assembly, an integrated inner well wall formwork, trestle main bridge legs, trestle main bridge, approach bridge, bidirectional hydraulic winch, and gantry support rollers. The integrated inner well wall formwork is installed on the full-ring formwork gantry assembly. The trestle main bridge passes through the space enclosed by the full-ring formwork gantry assembly and extends along the excavation direction of the frozen inclined shaft. The construction process is as follows: a stepping formwork trolley is used to pour the outer well wall of the frozen inclined shaft, and a trestle-type formwork trolley is used to pour the inner well wall. This invention can solve technical problems such as damage to the formed well wall when the rail-mounted formwork trolley moves forward and is fixed during the pouring of well walls in deep and long frozen inclined shafts, poor integrity of the inner wall due to separate pouring of the inner wall bottom plate and the side wall top plate, and mutual interference between the pouring of the inner well wall and the removal of waste rock during the pouring of well walls.

Description

Technical Field

[0001] This invention relates to the field of frozen inclined shaft construction technology. Specifically, it relates to a trestle-type formwork trolley and a construction process for pouring double-layer shaft walls in frozen inclined shafts. Background Technology

[0002] In recent years, deep and long frozen inclined shafts have gradually adopted the use of formwork trolleys for shaft wall pouring. The formwork trolley is supported by rails, and large formwork is fixed to the trolley gantry by a hydraulic device, which improves the efficiency of hydraulic demolding and formwork support of large formwork, solves the problem of integral pouring of the side walls and top slab of the inclined shaft, and forms a relatively independent transportation channel inside the trolley gantry. The wall construction quality is significantly improved compared with assembled formwork, and the mutual interference between transporting waste rock and pouring concrete shaft walls is reduced. Currently, some people are using bottom formwork trolleys and top formwork trolleys respectively in the construction of inclined shaft repair casing. First, a bottom formwork trolley is used to pour the concrete of the side wall root and bottom slab. After the bottom slab concrete has improved in strength, another top formwork trolley is used to pour the top slab and side walls of the shaft.

[0003] However, the formwork trolleys currently used in the freezing of inclined shafts still have some problems: ① The rail-mounted formwork trolleys need to be dragged by external force to move forward and be fixed. When the inclination angle of the inclined shaft increases slightly, the anchor points of the fixed formwork trolleys will cause significant damage to the already formed shaft wall; ② The rail support prevents the trolley gantry legs from landing directly on the ground, which weakens the longitudinal and lateral limiting (fixing) of the gantry legs, making it easy for the formwork to run away and the side wall to deform during concrete pouring; ③ The inner wall bottom plate and the side wall top plate are poured separately, which is not conducive to the integrity and water sealing of the inner wall; ④ The pouring of the bottom plate concrete and the removal of waste rock interfere with each other, making it impossible to achieve parallel operation of excavation and waste rock removal and construction of the inner and outer shaft walls. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to provide a trestle-type template trolley and a construction process for pouring double-layer well walls in frozen inclined shafts, so as to solve the technical problems such as damage to the formed well wall when the rail-mounted template trolley moves forward and is fixed during the pouring of well walls in deep and long frozen inclined shafts, poor integrity of the inner wall due to the separate pouring of the inner wall bottom plate and the side wall top plate, and mutual interference between the pouring of the inner well wall and the removal of waste rock.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0006] The trestle-type formwork trolley includes a full-ring formwork gantry assembly, an integrated inner well wall formwork, trestle main bridge legs, trestle main bridge, approach bridges, a bidirectional hydraulic winch, and gantry support rollers. The integrated inner well wall formwork is installed on the full-ring formwork gantry assembly. The trestle main bridge passes through the space enclosed by the full-ring formwork gantry assembly and extends along the excavation direction of the frozen inclined shaft. The approach bridges are located at both ends of the trestle main bridge, with one end of the approach bridge fixedly connected to the trestle main bridge and the other end supported on the bottom plate of the frozen well wall (outer well wall bottom plate or inner well wall). The gantry support rollers are installed on the full-ring formwork gantry assembly, and support slides are provided on both sides of the trestle main bridge. The gantry supports rollers that can slide along the support rails; the main bridge of the trestle is equipped with outriggers near the connection between the approach bridge and the main bridge of the trestle, and the main bridge is supported on the bottom plate of the frozen well wall by the outriggers; the main bridge outriggers are equipped with trestle lifting cylinders, which control the raising and lowering of the main bridge; along the forward direction of the trestle template trolley: the bidirectional hydraulic winch is installed on the main bridge of the trestle and near the front end of the main bridge, one wire rope of the bidirectional hydraulic winch is fixed to the front end of the full-ring template gantry assembly, and the other wire rope is fixed to the rear end of the full-ring template gantry assembly.

[0007] This invention, a trestle-type formwork trolley, improves upon traditional trestle-type formwork trolleys, enabling the one-time, integral casting of the entire inner wall of a frozen inclined shaft, resulting in better integrity and water sealing of the inner wall. Furthermore, the trestle-type formwork trolley utilizes a bidirectional hydraulic winch mounted on the main bridge to move the trestle and gantry formwork forward, without damaging the newly cast inner wall. The application of this trestle-type formwork trolley also provides a transportation channel for the excavation and waste disposal of inclined shafts and tunnels, facilitating parallel operations of inner wall casting and waste disposal.

[0008] The aforementioned trestle-type template trolley includes an integrated inner well wall template comprising a top mold, side molds, bottom corner molds, and a bottom mold; each side mold and bottom corner mold consists of two pieces; one end of the top mold is hinged to one end of one side mold, and the other end of the top mold is hinged to one end of the other side mold; the other ends of the two side molds are respectively bolted to one end of the two bottom corner molds, and the other ends of the two bottom corner molds are respectively hinged to both ends of the bottom mold;

[0009] The top formwork is connected to the top of the full-ring template gantry assembly via hydraulic support rods; the two side formworks are connected to the upper part of the side columns of the full-ring template gantry assembly via hydraulic support rods; the two bottom corner formworks are connected to the lower part of the side columns of the full-ring template gantry assembly via hydraulic support rods; the bottom formwork is located below the main bridge of the trestle bridge and is fixedly connected to the full-ring template gantry assembly.

[0010] The above-mentioned trestle-type template trolley, along the cross-sectional direction of the freezing inclined shaft: the bottom corner mold is an "L"-shaped structure integrally formed by the longitudinal bottom corner mold and the transverse bottom corner mold, the longitudinal bottom corner mold and the side mold are connected at an angle, and the direction of the angled connection is from the side wall to the top wall of the freezing inclined shaft; the transverse bottom corner mold is hinged to the bottom mold.

[0011] The aforementioned trestle-type template trolley has the following hydraulic support rods: the top mold connecting the top mold to the top of the full-ring template gantry assembly is a top mold lifting cylinder; the side mold connecting the side mold to the upper part of the side column of the full-ring template gantry assembly is a side mold cylinder; and the bottom corner mold connecting the bottom corner mold to the lower part of the side column of the full-ring template gantry assembly is a bottom corner mold cylinder.

[0012] The aforementioned trestle-type formwork trolley also includes a first screw jack and a second screw jack; the two ends of the first screw jack are respectively installed on the top mold and the full-ring formwork gantry assembly, and the second screw jack is respectively installed on the side mold and the full-ring formwork gantry assembly.

[0013] The construction process for pouring the double-layer well wall of a frozen inclined shaft involves using a stepping template trolley to pour the outer well wall and using the aforementioned trestle-type template trolley to pour the inner well wall.

[0014] The above-mentioned construction process for pouring the double-layer well wall of the frozen inclined shaft includes a step-type formwork trolley comprising a gantry assembly, a top formwork, side formwork, a stepping base, hydraulic tie rods, lifting cylinders, and a translating base. The top formwork is installed on top of the gantry assembly via a top formwork frame. The side formwork is connected to the side columns of the gantry assembly via side formwork hydraulic support rods, and the top formwork and the side formwork are hinged. The side columns of the gantry assembly are installed on the gantry bottom beam of the gantry assembly, and the bottom end of the side columns passes through the gantry bottom beam and is fixedly connected to the translating base. A lifting cylinder is installed on the side columns of the gantry assembly, which controls the raising or lowering of the side columns relative to the gantry bottom beam, and drives the translating base to raise or lower relative to the gantry bottom beam.

[0015] The stepping base is mounted on the lower surface of the gantry frame bottom beam via a slide rail, and the stepping base can slide along the slide rail, which extends along the longitudinal direction of the gantry frame bottom beam.

[0016] The stepping base includes a forward base, a follower base, and a connecting rod. The forward base and the follower base are fixedly connected by the connecting rod, which extends along the longitudinal direction of the gantry frame bottom beam. The follower base and the forward base are sequentially mounted on the lower surface of the gantry frame bottom beam via slide rails along the forward direction of the stepping template trolley. One end of the hydraulic pull rod is fixedly mounted on the lower surface of the gantry frame bottom beam adjacent to the follower base, and the other end is fixedly connected to the forward base.

[0017] This invention, a stepping formwork trolley, is an improvement upon the traditional formwork trolley. By incorporating a stepping base, hydraulic tie rods, and a translating base, it achieves trackless self-propelled movement, avoiding the significant damage to the already formed well wall caused by the need for anchor points when moving a rail-guided formwork trolley. Furthermore, the gantry legs of this invention are wide translating bases that can directly rest on the base plate, preventing the weakened longitudinal and lateral limiting (fixation) of the gantry legs of rail-guided formwork trolleys, which are prone to formwork slippage and sidewall deformation during concrete pouring due to the inability of the gantry legs to directly rest on the ground.

[0018] The above-mentioned construction process for the double-layer well wall of the frozen inclined shaft includes a top formwork lifting cylinder installed on the top formwork frame, which controls the lifting and lowering of the top formwork; grouting holes are provided on the top formwork; the hydraulic support rod connecting the side formwork to the side column of the gantry assembly is a side formwork cylinder; the side formwork is integrally formed from the top side formwork and the side side formwork, with the top side formwork hinged to the top formwork, and a support rod provided at one end of the side formwork; a side formwork through beam is installed on the top side formwork, with both ends of the through beam fixedly connected to the top side formwork and the upper part of the side column of the gantry assembly, respectively; a lateral screw is installed on the side formwork, with both ends of the lateral screw fixedly connected to the lower part of the side formwork and the side column of the gantry assembly, respectively; a ground screw is installed on the lower surface of the bottom beam of the gantry assembly, with the free end of the ground screw facing the bottom plate of the frozen inclined shaft.

[0019] The above-mentioned construction process for the double-layer well wall of a frozen inclined shaft, using the aforementioned walking-beam formwork trolley for pouring the outer well wall, is as follows:

[0020] During the pouring of the outer well wall, the top formwork and the side formwork of the stepping formwork trolley are supported by the lifting cylinder and the side formwork cylinder; and the supported formwork is reinforced by the side formwork through beam, the lateral screw and the ground screw; after the formwork is supported, the concrete of the outer well wall is poured.

[0021] After the outer well wall concrete has been poured for 12-16 hours, the stepping formwork trolley is demolded. After demolding, the stepping formwork trolley is moved. During movement, the stepping base and the translation base are alternately stepped forward and landed to achieve forward movement. When the stepping base steps forward, the lifting cylinder is controlled to support the translation base on the bottom plate of the outer well wall of the frozen inclined shaft. At this time, the stepping base is detached from the bottom plate of the outer well wall. The hydraulic tie rod is controlled to extend and push the stepping base to slide forward longitudinally along the bottom beam of the gantry frame. Then, the lifting cylinder is controlled to lift the translation base upward and detach it from the bottom plate of the outer well wall. At this time, the stepping base is supported on the bottom plate of the outer well wall. Then, the hydraulic tie rod is controlled to retract and pull the gantry frame assembly forward.

[0022] The above-mentioned construction process for pouring the double-layer well wall of a frozen inclined shaft, using the aforementioned trestle-type formwork trolley for pouring the inner well wall of the frozen inclined shaft, is as follows:

[0023] During the pouring of the inner well wall, the integrated inner well wall formwork of the trestle-type formwork trolley is opened to complete the formwork support. The top formwork, side formwork, bottom formwork, and bottom corner formwork of the trestle-type formwork trolley are supported by the top formwork lifting cylinder, the side formwork cylinder, and the bottom corner formwork cylinder. The opened formwork is reinforced by the first screw jack and the second screw jack. After the formwork support is completed, the inner wall of the inner well wall is poured into a single, integral concrete pour.

[0024] Four hours after the inner well wall concrete is poured, the front and rear approach bridges are retracted, and the main bridge support legs of the trestle are lifted upwards from the frozen well wall bottom plate by controlling the lifting cylinder of the trestle. The full-ring template gantry assembly is supported on the inner well wall bottom plate with initial strength by the bottom mold of the integrated inner well wall template. The bidirectional hydraulic winch is started to move the main bridge of the trestle forward to the next working position by dragging the steel wire rope fixed at the rear end of the full-ring template gantry assembly. The main bridge support legs of the trestle are then placed on the ground, the front and rear approach bridges are lowered, and the inner wall reinforcement is tied around the entire circumference of the front section of the trestle.

[0025] After the inner well wall concrete has completely solidified, the stepping formwork trolley is demolded; then, the height of the main bridge of the trestle is raised by controlling the lifting cylinder of the trestle, thereby driving the bottom mold of the integrated inner well wall formwork to detach from the bottom plate of the inner well wall; then, the bidirectional hydraulic winch is started so that the entire ring formwork gantry assembly moves forward to the next working position under the drag of the steel wire rope fixed at the front end of the entire ring formwork gantry assembly, thus completing the movement of the trestle formwork trolley.

[0026] The technical solution of the present invention achieves the following beneficial technical effects:

[0027] 1. This invention utilizes an improved step-type formwork trolley for pouring the outer wall of a frozen inclined shaft and an improved trestle-type formwork trolley for pouring the inner wall. This not only solves the problems of existing rail-mounted formwork trolleys, which suffer significant damage to the already formed shaft wall due to the need for anchor points during movement, and the weakened longitudinal and lateral restraint caused by the inability of the gantry legs of rail-mounted formwork trolleys to directly touch the ground, leading to formwork slippage and sidewall deformation during concrete pouring; it also solves the problems of poor integrity and water sealing of the inner wall due to the separate pouring of the inner wall bottom plate and sidewall top plate. Furthermore, the step-type formwork trolley of this invention has a wide transport channel, and the trestle-type formwork trolley also has a passable trestle channel, effectively solving the problem of mutual interference between the excavation and waste disposal and the pouring of concrete for the inner and outer walls of deep, long frozen inclined shafts, thus improving construction efficiency.

[0028] 2. This invention can solve the problem of mutual interference between the excavation and waste disposal and the pouring of concrete for the inner and outer layers of the shaft wall in deep and long frozen inclined shafts, and improve the construction quality of the overall shaft wall pouring. In the construction of deep and long frozen small-section inclined shafts, the improved step-type template trolley of this invention is used to pour the outer wall, and the improved trestle-type integral template trolley and construction method are used to implement the one-time integral pouring of the entire inner wall. This not only achieves no longitudinal construction joints in the inner wall and improves the integrity and water sealing of the shaft, but also creates parallel operation conditions for the excavation and waste disposal and the construction of the inner and outer layers of the shaft wall, which can provide a reference for the excavation and support of deep and long frozen inclined shafts. Attached Figure Description

[0029] Figure 1 Actual test photos of the stepping template trolley in an embodiment of the present invention;

[0030] Figure 2 A front view schematic diagram of the stepping template trolley in an embodiment of the present invention;

[0031] Figure 3 A side view of the stepping template trolley structure in an embodiment of the present invention;

[0032] Figure 4 A schematic diagram of the outer wall template of the stepping template trolley being extended (supported) in an embodiment of the present invention;

[0033] Figure 5 A schematic diagram of the shrinkage (demolding) of the outer wall template of the stepping template trolley in an embodiment of the present invention;

[0034] Figure 6 A front view schematic diagram of the trolley-type template trolley in an embodiment of the present invention;

[0035] Figure 7A side view of the trolley-type template trolley structure in an embodiment of the present invention;

[0036] Figure 8 A schematic diagram of the inner wall template support (formwork erection) of the trolley-type template carriage in an embodiment of the present invention;

[0037] Figure 9 A schematic diagram of the shrinkage (demolding) of the inner wall template of the trolley-type template carriage in an embodiment of the present invention;

[0038] Figures 10a to 10d This is a schematic diagram illustrating the usage instructions for the trestle-type template trolley in an embodiment of the present invention.

[0039] The reference numerals in the diagram are as follows: 1-Top formwork; 2-Top formwork lifting cylinder; 3-Side formwork; 4-Full-ring template gantry assembly; 5-Side formwork cylinder; 6-Bottom corner formwork cylinder; 7-Trestling lifting cylinder; 8-Trestling main bridge support leg; 9-Temporary platform; 10-Trestling main bridge; 11-Two-way hydraulic winch; 12-Bottom formwork; 13-Bottom corner formwork; 14-First screw jack; 15-Second screw jack; 16-Approach bridge; 17-Gantry support roller; 18-Trestling middle support leg; 19-Work window ; 20-Gantry frame bottom beam; 21-Stepping base; 22-Hydraulic tie rod; 23-Ground screw; 24-Tilt-overturning device; 25-Lifting cylinder; 26-Top mold frame; 27-Gantry assembly; 28-Side mold through beam; 29-Transfer base; 30-Grouting hole; 31-Side screw; 32-Support screw; 131-Longitudinal bottom corner mold; 132-Transverse bottom corner mold; 211-Forward base; 212-Following base; 213-Connecting rod; 301-Top side mold; 302-Side mold. Detailed Implementation

[0040] This embodiment conducts an engineering experiment on the freezing construction of the auxiliary inclined shaft of Shengfu Mine, further illustrating the construction process of pouring frozen inclined shaft concrete using a step-by-step and trestle-type formwork trolley according to the present invention.

[0041] 1. Project Overview

[0042] In this embodiment, the Shengfu Mine's auxiliary inclined shaft is designed to be 1760m long. Originally, a 37m shaft was constructed using a ground jet grouting pile + pre-grouting reinforcement method with open trenching. However, due to water inrush, construction was halted, and a freezing method was adopted instead. The frozen section of the shaft is designed to be 1050m long with a freezing depth of 110m, making it the longest frozen section of any inclined shaft in a global coal mine. The shaft has a net width of 5400mm and a net height of 4300mm. The frozen section is supported by a double-layer shaft wall, and temporary support during excavation is provided by a steel frame mesh canopy. The excavation width is 7300mm, the excavation height is 6550-6850mm, and the excavation cross-section is 42.1m. 2 ~44.3m 2 .

[0043] 2. Use a walking-beam formwork trolley to freeze the outer wall of the inclined shaft.

[0044] Previously, the outer wall formwork trolley used a hydraulic system to fix the large formwork onto the trolley's gantry. The top formwork was adjustable, and the side formwork was hinged to the top formwork. The lower part of the side formwork could be folded inward at a certain angle, improving the efficiency of hydraulic demolding and formwork support for the large formwork. This solved the problem of integral pouring of the inclined shaft sidewalls and top slab. The trolley gantry could form a relatively independent transportation channel, resulting in significantly improved wall construction quality compared to assembled formwork, and reducing the mutual interference between transporting waste rock and pouring concrete for the shaft wall. Currently, the support and movement of formwork trolleys in shaft engineering and frozen inclined shaft engineering are basically rail-based. The main advantages are simple structure, ease of underground installation, and simple movement. However, the following disadvantages exist:

[0045] ① It requires external force to move forward and be fixed. When the inclination angle of the inclined shaft increases slightly, the anchor point of the steel wire rope fixing the template will cause significant damage to the already formed well wall.

[0046] ② The track support also caused the trolley to become dependent on the base plate, which required the formwork trolley to maintain a certain distance from the newly poured concrete base plate, delaying the pouring time of the frozen inclined shaft outer wall and affecting the parallel operation of tunneling and waste disposal and concrete base plate pouring.

[0047] ③ The track support prevents the gantry legs from landing directly on the ground, weakening the longitudinal and lateral limiting (fixing) of the gantry legs, making it easy for the formwork to run away and the side walls to deform during concrete pouring.

[0048] (1) Structure of the stepping template trolley in this embodiment

[0049] This embodiment uses an improved stepping template trolley for the auxiliary inclined shaft of the Shengfu Mine (see...). Figure 1 The side walls and top slab of the outer wall are reinforced with concrete, and hydraulic formwork is used for both hydraulic movement and formwork closure. The lining formwork is 6100mm long, with external dimensions of 6580 / 6780mm wide × 5890mm / 6090mm high, a gantry clearance of 3160mm × 3800mm, an outline radius R = 3290 / 3390mm, and a trolley panel thickness of 10mm. All other test items comply with the Q / 4103BA2017-2004 standard.

[0050] like Figure 2 and Figure 3As shown, the stepping template trolley in this embodiment includes a gantry assembly 27, a top mold 1, a side mold 3, a stepping base 21, a hydraulic tie rod 22, a lifting cylinder 25, and a sliding base 29. The top mold 1 is mounted on the top of the gantry assembly 27 via a top mold frame 26. The side mold 3 is connected to the side columns of the gantry assembly 27 via a side mold hydraulic support rod. The top mold 1 and the side mold 3 are hinged. The side columns of the gantry assembly 27 are mounted on the gantry bottom beam 20 of the gantry assembly 27, and the bottom end of the side column of the gantry assembly 27 passes through... The gantry frame bottom beam 20 is fixedly connected to the translation base 29; a lifting cylinder 25 is installed on the side column of the gantry frame assembly 27, which controls the side column of the gantry frame assembly 27 to rise or fall relative to the gantry frame bottom beam 20, and drives the translation base 29 to rise or fall relative to the gantry frame bottom beam 20; the stepping base 21 is installed on the lower surface of the gantry frame bottom beam 20 via a slide rail, and the stepping base 21 can slide along the slide rail, which extends along the longitudinal direction of the gantry frame bottom beam 20;

[0051] The stepping base 21 includes a forward base 211, a following base 212, and a connecting rod 213. The forward base 211 and the following base 212 are fixedly connected by the connecting rod 213, which extends along the longitudinal direction of the gantry frame bottom beam 20. The following base 212 and the forward base 211 are sequentially mounted on the lower surface of the gantry frame bottom beam 20 via slide rails along the forward direction of the stepping template trolley. One end of the hydraulic tie rod 22 is fixedly mounted on the lower surface of the gantry frame bottom beam 20 adjacent to the following base 212, and the other end is fixedly connected to the forward base 211.

[0052] A top mold lifting cylinder is installed on the top mold frame 26, which controls the lifting and lowering of the top mold 1; the top mold 1 has grouting holes 30; the side mold hydraulic support rod connecting the side mold 3 and the side column of the gantry assembly 27 is a side mold cylinder 5 (lateral telescopic mechanism); the side mold 3 is integrally formed by the top side mold 301 and the side mold 302, the top side mold 301 is hinged to the top mold 1, and one end of the side mold 302 is provided with a support rod; the top side mold A side mold through beam 28 is installed on the top mold 301, and the two ends of the side mold through beam 28 are fixedly connected to the upper part of the side column of the top mold 301 and the gantry assembly 27, respectively; a lateral screw 31 is installed on the side mold 302, and the two ends of the lateral screw 31 are fixedly connected to the lower part of the side mold 302 and the side column of the gantry assembly 27, respectively; a ground screw 23 is installed on the lower surface of the bottom beam 20 of the gantry, and the free end of the ground screw 23 faces the bottom plate of the freezing inclined shaft.

[0053] When using the stepping formwork trolley to pour the outer wall of a frozen inclined shaft, in a frozen inclined shaft where the outer bottom plate has already been poured, the top formwork 1 and the side formwork 3 of the stepping formwork trolley are supported by the lifting cylinder 25 and the side formwork cylinder 5; and the supported formwork is reinforced by the side formwork through beam 28, the lateral screw 31 and the ground screw 23; after the formwork is supported, the concrete for the outer wall is poured; after the outer wall concrete has been poured for 12-16 hours, the stepping formwork trolley is demolded; after demolding, the stepping formwork trolley is moved, and during movement, the stepping base 21 and the flat... The moving base 29 moves forward by alternating between stepping forward and landing. When the stepping base 21 steps forward, the lifting cylinder 25 supports the moving base 29 on the bottom plate of the outer well wall of the frozen inclined shaft. At this time, the stepping base 21 detaches from the bottom plate of the outer well wall. The hydraulic rod 22 extends and pushes the stepping base 21 to slide forward along the longitudinal direction of the gantry frame bottom beam 20. Then, the lifting cylinder 25 lifts the moving base 29 upward and detaches it from the bottom plate of the outer well wall. At this time, the stepping base 21 is supported on the bottom plate of the outer well wall. Then, the hydraulic rod 22 retracts and pulls the gantry frame assembly 27 forward as a whole.

[0054] like Figure 2 As shown, the mast of the template trolley is equipped with a lifting cylinder (vertical lifting mechanism) and a translation base (the translation base is moved by the translation cylinder, thereby adjusting the position on the template trolley), which can control the up and down movement of the mast and top template (formwork support, demolding), and adjust the posture of the mast and template; the mast is equipped with a side template cylinder, which can control the side template to open (formwork support) and shrink (demolding) (see... Figure 4 and Figure 5 Lateral screws are used to reinforce the spread-out formwork to prevent it from running away during concrete pouring.

[0055] like Figure 3 As shown, a stepping base is installed on the 8.5m long gantry bottom beam. The stepping base can move longitudinally under the bottom beam of the gantry. A longitudinal hydraulic tie rod is provided between the stepping base and the bottom beam of the gantry. The front end of the hydraulic tie rod is fixed on the stepping base, and the rear end of the hydraulic tie rod is fixed under the bottom beam of the gantry. The stepping base drags the gantry and the template (6.1m long) by means of the hydraulic tie rod. The hydraulic step length is 1.2m. The gantry translation base and the stepping base step and land alternately to realize the forward movement of the stepping template trolley.

[0056] (2) Features of the improved stepping self-propelled template trolley

[0057] ① By utilizing the longitudinal hydraulic tie rod between the longitudinal bottom beam (gantry bottom beam) of the gantry assembly and the stepping base, the translation base and the stepping base alternately step and land, with each step length being 1.2m, without the need for a track.

[0058] ② In order to move the gantry and formwork together, the trolley gantry and formwork (including supports and through beams) have good rigidity and integrity, which not only improves the efficiency and reliability of formwork positioning, hydraulic support and demolding, but also provides a wide transportation channel, which facilitates parallel operations of waste rock removal and wall construction.

[0059] ③ The mast assembly of the template trolley is equipped with lifting cylinders and translation bases at the front, rear, left, and right, which can control the up and down and left and right movement of the mast and template respectively, flexibly adjust the template posture, and ensure the accurate positioning of the overall template center height, tilt angle, orientation, verticality and horizontality.

[0060] ④ The bottom beam of the step-type formwork trolley gantry assembly has wide support legs (i.e., translation base) for stable grounding; the front end of the gantry is equipped with diagonal bracing, which increases the rigidity of the trolley formwork against forward tilting and deformation. When the inclination angle of the inclined shaft increases, auxiliary traction is added at the rear end of the gantry to ensure that the formwork does not slide down, and diagonal bracing is added at the front end of the gantry (i.e., the anti-tipping device 24 in the figure) to strengthen the fixation.

[0061] (3) Characteristics of external wall step-forward formwork trolley wall construction

[0062] Utilizing the improved trackless self-propelled structure of the stepping formwork trolley, as well as its convenient demolding, forward movement, formwork support, alignment, and reinforcement operations, combined with full-face tunneling construction, the bottom slab was replaced, the bottom arch beam was installed, and the outer wall concrete bottom slab was poured under the extended secondary conveyor belt. The original internal freezing pipe corresponding to the top of the formwork was used to pour mortar, and the concrete of the two sides of the outer wall and the top arch was poured, realizing parallel operations of tunneling and waste rock removal and outer wall concrete pouring.

[0063] 3. Use a trestle-type formwork trolley to carry out the overall construction of the inner wall of the frozen inclined shaft.

[0064] Previously, the inner well wall formwork trolley was not much different from the outer well wall formwork trolley. It was mainly a track-type (top formwork and side formwork) integral formwork trolley, which solved the problem of integral pouring of the inclined well sidewalls and top slabs. The bottom slab of the inner well wall was generally poured in advance. In some projects, the bottom slab of the inner wall was poured after the sidewalls and top slab of the inner wall were poured. At present, some people are using bottom formwork trolleys and side formwork and top formwork trolleys respectively in the construction of inclined well repair casing. First, a bottom formwork trolley is used to pour the base of the sidewalls and the bottom slab. After the bottom slab concrete has increased in strength, another formwork trolley is used to pour the top slab and sidewalls of the well wall. First, the inner wall of the well is not as well-integrated and water-sealing as when the entire ring is poured as a whole, with the base slab poured separately. Second, pouring the inner wall base slab concrete separately inevitably affects the parallel operations of tunneling and waste removal, outer wall construction, and inner wall construction. Third, the track support causes the formwork trolley to become dependent on the base slab, requiring a certain distance between the formwork trolley and the newly poured concrete base slab, increasing and expanding the construction area from the tunneling face to the inner wall, and adding difficulty to the construction organization of the inner wall base slab and well wall. Although using two formwork trolleys to pour the inner wall base slab and the side wall top slab separately can solve the problem of parallel operations of inner wall concrete pouring, tunneling and waste removal, and outer wall construction, it adds an extra set of formwork trolleys, requires increasing the strength of the base slab concrete, and the two formwork trolleys must be spaced a certain distance apart, increasing the number of procedures and construction area, making the inner wall construction process more complex.

[0065] (1) The trestle-type integral template trolley structure in this embodiment

[0066] The improved trestle-type integral formwork trolley in this embodiment is suitable for pouring the inner wall of a small cross-section concrete in a frozen inclined shaft. It utilizes an extra-long trestle main bridge in the frozen inclined shaft to achieve the one-time integral casting of the entire inner wall.

[0067] The improved structure of the trestle-type integrated template trolley in this embodiment is shown below. Figure 6 and Figure 7 It consists of a top mold 1, a top mold lifting cylinder 2, a side mold 3, a side mold cylinder 5, a bottom corner mold 13, a bottom corner mold cylinder 6, a full-ring template gantry assembly 4 (including the bottom mold), a trestle main bridge 10, a trestle lifting cylinder 7, a translation mechanism (trestle main bridge support leg 8), front and rear approach bridges 16, anti-buoyancy screw jacks (first screw jack 14 and second screw jack 15), front-end ground anchor anti-buoyancy tension fiber, a two-way hydraulic winch 11 (winch), a hydraulic system, and an electrical control system.

[0068] Both the side mold 3 and the bottom corner mold 13 are in pairs; one end of the top mold 1 is hinged to one end of one of the side mold 3, and the other end of the top mold 1 is hinged to one end of the other side mold 3; the other ends of the two side molds 3 are respectively bolted to one end of the two bottom corner molds 13, and the other ends of the two bottom corner molds 13 are respectively hinged to both ends of the bottom mold 12; the top mold 1 is connected to the top of the full-ring template gantry assembly 4 via a hydraulic support rod (top mold lifting cylinder 2), and the two side molds 3 are connected to the upper part of the side columns of the full-ring template gantry assembly 4 via hydraulic support rods (side mold cylinders 5); the two bottom corner molds 13 are connected to the full-ring template gantry assembly via hydraulic support rods (bottom corner mold cylinders 6). The lower part of the side column of 4 is connected; the bottom formwork 12 is located below the main bridge 10 of the trestle bridge and is fixedly connected to the full-ring template gantry assembly 4; along the cross-sectional direction of the freezing inclined shaft: the bottom corner formwork 13 is an "L"-shaped structure integrally formed by the longitudinal bottom corner formwork 131 and the transverse bottom corner formwork 132, the longitudinal bottom corner formwork 131 and the side formwork 3 are connected at an angle, and the angled connection direction is from the side wall of the freezing inclined shaft to the top wall; the transverse bottom corner formwork 132 is hinged to the bottom formwork 12; the two ends of the first screw jack 14 are respectively installed on the top formwork 1 and the full-ring template gantry assembly 4, and the second screw jack 15 is respectively installed on the side formwork 3 and the full-ring template gantry assembly 4;

[0069] The main bridge 10 of the trestle passes through the space enclosed by the full-ring formwork gantry assembly 4 and extends along the excavation direction of the frozen inclined shaft; the approach bridge 16 is located at both ends of the main bridge 10 of the trestle, one end of the approach bridge 16 is fixedly connected to the main bridge 10 of the trestle, and the other end of the approach bridge 16 is supported on the bottom plate of the frozen shaft wall; the gantry support rollers 17 are installed on the full-ring formwork gantry assembly 4, and the main bridge 10 of the trestle is provided with support rails on both sides, and the gantry support rollers 17 can slide along the support rails; the main bridge 10 of the trestle is located near the connection between the approach bridge 16 and the main bridge 10 of the trestle. The trestle main bridge support leg 8 is installed on the trestle, and the trestle main bridge 10 is supported on the bottom plate of the frozen well wall by the trestle main bridge support leg 8; the trestle lifting cylinder 7 is installed on the trestle main bridge support leg 8, and the trestle lifting cylinder 7 controls the raising and lowering of the trestle main bridge 10; along the forward direction of the trestle template trolley: the bidirectional hydraulic winch 11 is installed on the trestle main bridge 10 and adjacent to the front end of the trestle main bridge 10, one wire rope of the bidirectional hydraulic winch 11 is fixed to the front end of the full ring template gantry assembly 4, and the other wire rope is fixed to the rear end of the full ring template gantry assembly 4.

[0070] During the pouring of the inner well wall, the top formwork 1, side formwork 3, bottom formwork 12, and bottom corner formwork of the trestle-type formwork trolley are supported by the top formwork lifting cylinder 2, the side formwork cylinder 5, the bottom corner formwork cylinder 6, and the trestle lifting cylinder 7. The formwork is then reinforced by the first screw jack 14 and the second screw jack 15 to complete the formwork support. After the formwork support is completed, the inner wall of the inner well wall is poured into a single, continuous concrete pour.

[0071] Four hours after the inner well wall concrete is poured, the front and rear approach bridges 16 are retracted, and the main bridge support legs 8 of the trestle are lifted off the frozen well wall bottom plate by controlling the lifting cylinder 7 of the trestle. The full-ring template gantry assembly 4 is supported on the inner well wall bottom plate with initial strength by the bottom mold of the integrated inner well wall template. The bidirectional hydraulic winch 11 is started so that the main bridge 10 of the trestle moves forward to the next working position under the drag of the steel wire rope fixed at the rear end of the full-ring template gantry assembly 4. The main bridge support legs 8 of the trestle are then placed on the ground, the front and rear approach bridges are lowered, and the inner wall reinforcement is tied around the front section of the trestle.

[0072] After the inner well wall concrete has solidified for 16 hours, the stepping formwork trolley is demolded. Then, the height of the main bridge 10 of the trestle is raised by controlling the lifting cylinder 7 of the trestle, thereby causing the bottom mold of the integrated inner well wall formwork to detach from the bottom plate of the inner well wall. Then, the bidirectional hydraulic winch 11 is started so that the entire ring formwork gantry assembly 4 is dragged forward to the next working position by the steel wire rope fixed at the front end of the ring formwork gantry assembly 4, thus completing the movement of the trestle formwork trolley.

[0073] Main technical parameters of the integrated formwork trolley for the auxiliary inclined shaft of Shengfu Mine:

[0074] ① The total length of the trolley is 28.6m, the template length is 6200mm; the main bridge of the trestle is 16m long; the lining overlap is 100-200mm (the lining overlap length in this embodiment is 200mm), and the lining length of each formwork is 6000mm.

[0075] ②Clear dimensions: 2600mm × 2250mm;

[0076] ③ Formwork erection method: hydraulic positioning;

[0077] ④ Travel method: Self-propelled hydraulic winch (two-way hydraulic winch);

[0078] ⑤ Cart travel speed: 3m / min;

[0079] ⑥ Maximum demolding allowance on one side: 100mm;

[0080] ⑦ Horizontal adjustment range: 100mm (one side);

[0081] ⑧ System flow rate: Q = 23 L / min;

[0082] ⑨ System operating pressure: P = 16 MPa;

[0083] ⑩ Permissible concrete pouring speed: ≤1m / h.

[0084] This trolley is equipped with a trestle; vehicles are prohibited from crossing the trestle during lining to prevent formwork displacement due to vibration. After lining is completed, the trestle height and other related components must be adjusted to separate the trestle from the formwork. The trestle's ends and middle support legs must be firmly supported to allow vehicles to pass. During lining, all screw rods and anti-buoyancy jacks must be firmly supported to prevent floating or formwork displacement. The vehicle weight limit is ≤20 tons, and the vehicle speed limit is ≤5 km / h. The maximum climbing ability of the trolley and trestle is ≥6°; all electrical components on the trolley are explosion-proof.

[0085] The trestle-type integral formwork trolley has six formwork panels. The top formwork and a pair of side formwork panels are connected to the top of the gantry and the columns by hydraulic support rods. The bottom formwork panel is located under the main bridge of the trestle and is fixedly connected to the gantry columns. A pair of bottom corner formwork panels are connected to the gantry by hydraulic support rods. The upper part of the side formwork panels is hinged to the top formwork panel, and the lower part of the bottom corner formwork panels is hinged to the bottom formwork panel. The lower part of the side formwork panels and the bottom corner formwork panels are adjusted by hydraulic rods to achieve a beveled connection. The bottom corner formwork panels and the side formwork panels can be connected to each other with bolts to form an integral formwork panel for formwork support. Alternatively, the bolts can be removed and the hydraulic rods can be adjusted to separate and demold the bottom corner formwork panels and the side formwork panels.

[0086] The trestle-type integrated formwork trolley does not rely on the extension and locking of longitudinal hydraulic rods to move forward. Instead, it uses a two-way hydraulic winch and winch wire rope. The two-way hydraulic winch controls the wire rope to pull the main bridge and gantry (carrying the formwork) forward separately and in stages. The improved trestle-type integrated formwork trolley in this embodiment has the following characteristics:

[0087] ① Utilizing the extra-long main bridge of the trestle bridge, the gantry (including supporting rolling guide wheels) and its own bidirectional hydraulic winch, wire rope, outriggers, etc., it can move independently without the need for tracks; the gantry and formwork can be moved on the long-span main bridge, and the movement of the formwork and the trestle bridge transport channel do not depend on the bottom plate of the inclined shaft.

[0088] ② The integral formwork trolley comes with bottom formwork, bottom corner formwork, side formwork, and top formwork, enabling the entire 6m long inner wall of the inclined shaft to be cast in one go without longitudinal construction joints; the trolley has an independent transportation channel and a work platform for tying steel bars, realizing parallel operations of tunneling and waste rock removal and well wall concrete pouring.

[0089] ③ The beveled joints of the side formwork and bottom formwork of the overall formwork trolley facilitate the separation and connection of the side formwork and bottom corner formwork, and also ensure the accurate positioning and (bolt) tightening of the connected formwork. All formwork is supported by a larger and thicker liner, which greatly enhances the integrity, rigidity, interface flatness and wall construction dimensional reliability of the formwork.

[0090] ④ The main bridge of the overall formwork trolley is equipped with large outriggers that can be moved horizontally and raised and lowered. The gantry is also equipped with diagonal bracing at the front end, which not only facilitates the adjustment of the trolley's posture but also improves the reliability of support and fixation. When the inclination angle of the inclined shaft increases, diagonal bracing can be added at the front end to strengthen the fixation, and auxiliary traction can be added at the rear end of the gantry to ensure that the formwork trolley does not slip.

[0091] ⑤ The integral formwork is located at the front section of the main bridge with an ultra-long beam. The main bridge spans the bottom slab section that is being poured and the bottom slab section that has been demolded. Therefore, the new support point of the rear leg of the main bridge is not on the concrete bottom slab that has just been demolded. The concrete consolidation time of the new support point is extended and the strength is increased, which is conducive to the speed of the trestle-type integral formwork trolley to cope with the construction of the inner well wall.

[0092] ⑥ The gantry and formwork of the trolley are equipped with a total of 7 anti-buoyancy screw jacks at the front, middle and rear. A set of ground anchor anti-buoyancy tensioning fiber is also set at the front end, and multiple sets of formwork screw jacks are set to prevent the overall formwork from floating and running away during the concrete pouring process.

[0093] (2) Construction and operation steps of the trestle-type integral formwork trolley

[0094] Step 1: After the newly poured base slab concrete has reached a certain early strength, retract the front and rear approach bridges, lift the main bridge support legs (sliding base) of the trestle bridge, and operate the bidirectional hydraulic winch to pull the trestle bridge forward to the next working position.

[0095] Step 2: Lower the main bridge outriggers to the ground, lower the front and rear approach bridges, and tie the inner wall reinforcement around the entire circumference of the front section of the trestle. After the concrete of the well wall has solidified and increased in strength, remove the formwork positioning supports, end plates, and fixing bolts connecting the side formwork and the bottom corner formwork. In sequence, fold the bottom corner formwork inward, fold the lower part of the side formwork inward, lower the height of the top formwork, and raise the height of the main bridge of the trestle (to detach the bottom formwork from the bottom plate of the well wall), thus completing the complete detachment of the steel formwork surface of the formwork trolley from the lining surface.

[0096] Step 3: Control the bidirectional hydraulic winch to pull the gantry assembly and formwork along the main bridge of the trestle to the next section of concrete pouring position; align and fix the formwork trolley.

[0097] Step 4: The entire inner ring is poured with concrete in one go.

[0098] (3) Inner wall trestle type integral formwork trolley wall construction technology

[0099] ① Reinforcing steel bars are tied at the front end of the formwork trolley.

[0100] In the shaft area 49.5m from the tunneling face, the outer shaft wall has been poured. The trestle-type integral formwork trolley occupies about 28.6m, forming an independent waste rock transportation channel. The trestle's ascending approach bridge is about 8m long, and the main bridge is 16m long. The front section of the main bridge can be used to tie the inner wall full ring (bottom slab, side walls, and top slab) reinforcement. Tying the inner wall reinforcement can be carried out in parallel with the excavation and waste rock disposal and the outer wall construction.

[0101] ② Template trolley demolding and forward movement

[0102] Four hours after the inner wall top slab concrete is poured, the bottom slab concrete has solidified for a period of time. The main bridge legs and approach bridges of the formwork trolley can then be lifted off the ground. The trolley uses its own bidirectional hydraulic winch and steel wire rope to pull the main bridge and approach bridges along the support rollers on the gantry columns to the required position. After 16 hours after the concrete is poured, the concrete well wall has a certain early strength, and the overall formwork trolley can be demolded. Finally, using the 16m long main bridge and its own bidirectional hydraulic winch and steel wire rope, the trolley gantry and the overall formwork (6.2m long) are pulled forward 6m along the main bridge.

[0103] The movement of the trolley bridge, demolding, and overall template movement shall be carried out in the following steps:

[0104] like Figure 10a As shown in the first step, after the concrete has solidified for 4 hours, start the hydraulic system, turn on the remote control switch, operate the reversing valve button, retract the front and rear approach bridges, and lift the main bridge support legs (sliding base) of the trestle; operate the bidirectional hydraulic winch (hoist) to pull the trestle forward to the next working position; operate the reversing valve button again to lower the main bridge support legs to the ground and lower the front and rear approach bridges.

[0105] like Figure 10b As shown in the second step, after the concrete has solidified for 16 hours, remove the formwork positioning supports such as the screw rods and the end plates, and remove the connecting bolts of the side formwork and bottom corner formwork. Operate the reversing valve button to control the hydraulic rod of the bottom corner formwork to fold inward and retract, and control the hydraulic rod of the (side) side formwork to fold the lower part of the side formwork inward, so that the side formwork is separated from the lining surface. Remove the anti-buoyancy screw jacks and ground anchor anti-buoyancy tension cables. Operate the reversing valve button to control the top formwork lifting cylinder to lower the top formwork slightly, so that the top formwork is separated from the well wall. Operate the reversing valve button to control the trestle lifting cylinder to slightly raise the bottom formwork, so that the bottom formwork is separated from the bottom plate of the well wall, completing the separation of the steel formwork surface of the formwork trolley from the lining surface, and the front section of the reinforcing steel is tied.

[0106] like Figure 10cAs shown in the third step, after the inner wall reinforcement of the front section of the trestle is tied, debris can be cleared, and the ventilation ducts, compressed air pipes, cables, etc. hanging on the formwork trolley can be removed. The reversing valve button is operated to control the bidirectional hydraulic winch to pull the gantry assembly and formwork along the main bridge of the trestle to the position of the next section of concrete wall construction. Then, the formwork is aligned, the end plate is plugged, the water-stop steel plate is welded, the formwork is fixed, and preparation is made for concrete pouring.

[0107] When the hydraulic cylinder retracts, it must be done in stages; never force demolding in one go. The retraction stroke of the hydraulic cylinder is 180mm to 300mm. Remove any residue from the formwork surface, check the surface quality, and spray or brush release agent onto the formwork surface according to the operating procedures. Check the quality of the demolding well wall, and treat the surfaces of the formwork overlaps, pouring openings, and observation openings, marking the sidewalls with appropriate markings.

[0108] like Figure 10d As shown in the fourth step, pour the concrete and wait for it to solidify before starting the next cycle.

[0109] ③ Hydraulic formwork support and template trolley inspection and positioning.

[0110] Adjust the main bridge outriggers of the trestle to straighten the trolley gantry and formwork; raise the top formwork to position, then extend the hydraulic rods of the bottom corner formwork and side formwork, adjust the side formwork of the formwork trolley to match the bevel of the bottom corner formwork, and use bolts to connect the side formwork and bottom corner formwork into a whole.

[0111] Strictly adjust the center height, left and right position, and tilt of the template trolley according to the laser pointer to ensure the accuracy of the height, left and right position, and tilt of each control point of the template trolley, as well as the verticality of the side templates and the symmetry of the template cross-section.

[0112] After the template trolley is positioned and inspected to be qualified, install and tighten the lateral screws, and secure the anti-buoyancy screws and ground anchor anti-buoyancy tension bars; install the reinforcing waterstop steel strip, end plate, and symmetrical screws. When the inclination angle of the inclined shaft increases, add diagonal bracing at the front end of the trolley column gantry.

[0113] ④ Integral pouring of concrete well walls

[0114] Ten vent holes (also serving as vibration ports) were opened in the bottom formwork, and the bottom slab concrete was manually vibrated with a vibrator. A total of eight vibrators were installed on the lining of the side and top formwork of the trolley, and the vibration was gradually turned on according to the changes in the concrete pouring position. A total of nine working windows (also serving as vibration ports) were set in the side and top formwork of the trolley, and the concrete was manually vibrated with a vibrator according to the concrete pouring position to avoid leaving any unvibrated dead corners.

[0115] 4. Application Effects of Step-by-Step and Trestle-Type Formwork Trolleys in Engineering

[0116] The Shengfu Mine's frozen auxiliary inclined shaft utilizes an improved walking-type external wall formwork trolley construction technology, combined with full-face tunneling construction technology. The base slab is constructed below the extended secondary conveyor belt, and the freezing pipe on the top of the formwork trolley is used to pour concrete for the outer wall sides and the top arch. Relatively speaking, the walking-type formwork trolley has a simple bottom, a large internal transport channel, and convenient forward movement and posture adjustment. The external wall concrete pouring operation is simple, and it cleverly and efficiently realizes parallel operations of tunneling and waste rock removal and external wall concrete pouring, improving the safety of deep and long frozen inclined shaft excavation and masonry construction.

[0117] The Shengfu Mine's frozen auxiliary inclined shaft utilizes a newly developed trestle-type integral formwork trolley and construction technology, achieving for the first time parallel operations of shaft excavation and waste disposal with inner wall concrete pouring. This ensures the convenience and continuity of the integral pouring of the inner wall, and enables the entire inner wall to be poured in one go without longitudinal construction joints, thus improving the integrity and water sealing of the shaft.

[0118] The Shengfu Mine's frozen auxiliary inclined shaft achieved an average excavation and lining (well completion) speed of 50.8m / month for the 1031m underground frozen section, with a maximum single-month well completion speed of 102.4m / month, steadily improving the excavation and lining construction speed of the frozen inclined shaft.

[0119] 5. Conclusion

[0120] (1) The improved step-type template trolley combined with the full-face tunneling construction technology, and the construction process of pouring the outer wall bottom plate under the second conveyor belt, cleverly and efficiently realized the parallel operation of tunneling and waste rock removal and outer wall concrete pouring.

[0121] (2) The application of the newly developed trestle-type integral template trolley and construction technology has laid the foundation for the parallel operation of excavation, waste disposal and wall construction of (small cross-section) inclined shafts and tunnels, ensuring the convenience and continuity of the integral pouring of the inner wall. The inner wall, which is integrally cast in one go, has no longitudinal construction joints, which improves the integrity and water sealing of the shaft wall structure.

[0122] (3) The improved step-type outer wall formwork trolley and the newly developed trestle-type inner wall integral formwork trolley and their construction technology have created conditions for parallel operation of the three major links of tunneling and waste rock removal, outer wall construction and inner wall construction, and improved the level of frozen inclined shaft wall construction equipment in my country.

[0123] In this embodiment, for the construction of the frozen auxiliary inclined shaft of Shengfu Mine, the original template trolley track was abandoned, and the step-type outer wall template trolley was improved. The trestle-type integral template trolley technology used in tunnel engineering was adopted and improved. A trestle-type inner wall integral template trolley suitable for the relatively small cross-section wall construction of frozen inclined shafts was designed. The tunneling and wall construction processes were improved, realizing the parallel operation of tunneling and waste rock removal and the construction of inner and outer shaft walls.

Claims

1. A construction process for pouring double-layer well walls in a frozen inclined shaft, characterized in that, The outer wall of the frozen inclined shaft is poured using a stepping formwork trolley, and the inner wall of the frozen inclined shaft is poured using a trestle-type formwork trolley. The trestle-type formwork trolley includes a full-ring formwork gantry assembly (4), an integrated inner well wall formwork, trestle main bridge support legs (8), trestle main bridge (10), approach bridge (16), a two-way hydraulic winch (11), and gantry support rollers (17). The integrated inner well wall formwork is installed on the full-ring formwork gantry assembly (4). The trestle main bridge (10) passes through the space enclosed by the full-ring formwork gantry assembly (4) and extends along the excavation direction of the frozen inclined shaft. The approach bridge (16) is located at both ends of the trestle main bridge (10), one end of the approach bridge (16) is fixedly connected to the trestle main bridge (10), and the other end of the approach bridge (16) is supported on the bottom plate of the frozen well wall. The gantry support rollers (17) are installed on the full-ring formwork gantry assembly (4), and support rails are provided on both sides of the trestle main bridge (10). The gantry support roller (17) can slide along the support rail; the gantry main bridge support leg (8) is installed on the gantry main bridge (10) near the connection between the approach bridge (16) and the gantry main bridge (10), and the gantry main bridge (10) is supported on the bottom plate of the frozen well wall by the gantry main bridge support leg (8); the gantry main bridge support leg (8) is equipped with a gantry lifting cylinder (7), and the gantry main bridge (10) is raised and lowered by the gantry lifting cylinder (7); along the forward direction of the gantry template trolley: the bidirectional hydraulic winch (11) is installed on the gantry main bridge (10) and near the front end of the gantry main bridge (10), one wire rope of the bidirectional hydraulic winch (11) is fixed to the front end of the full ring template gantry assembly (4), and the other wire rope is fixed to the rear end of the full ring template gantry assembly (4); The method for pouring the inner wall of a frozen inclined shaft using the aforementioned trestle-type template trolley is as follows: When pouring the inner well wall, the integrated inner well wall template of the trestle-type template trolley is opened to complete the formwork support; after the formwork support is completed, the inner wall of the inner well wall is poured into a whole ring of concrete in one go. Four hours after the inner well wall concrete is poured, the front and rear approach bridges (16) are retracted, and the main bridge support legs (8) of the trestle are lifted off the frozen well wall bottom plate by controlling the lifting cylinder (7) of the trestle. The full ring template gantry assembly (4) is supported on the inner well wall bottom plate with initial strength by the bottom mold of the integrated inner well wall template. The bidirectional hydraulic winch (11) is started so that the main bridge (10) of the trestle moves forward to the next working position under the drag of the steel wire rope fixed at the rear end of the full ring template gantry assembly (4). The main bridge support legs (8) of the trestle are placed on the ground, the front and rear approach bridges (16) are lowered, and the inner wall reinforcement is tied in the full ring at the front of the trestle. After the inner well wall concrete has solidified for 16 hours, the step-type template trolley is demolded; then, the height of the main bridge (10) of the trestle is raised by controlling the lifting cylinder (7) of the trestle, thereby driving the bottom mold of the integrated inner well wall template to detach from the bottom plate of the inner well wall; then the bidirectional hydraulic winch (11) is started so that the entire ring template gantry assembly (4) moves forward to the next working position under the drag of the steel wire rope fixed at the front end of the entire ring template gantry assembly (4), thus completing the movement of the trestle template trolley.

2. The construction process for pouring double-layer well walls in a frozen inclined shaft according to claim 1, characterized in that, The integrated inner well wall template includes a top mold (1), a side mold (3), a bottom corner mold (13), and a bottom mold (12); the side mold (3) and the bottom corner mold (13) are both in pairs; one end of the top mold (1) is hinged to one end of one side mold (3), and the other end of the top mold (1) is hinged to one end of the other side mold (3); the other ends of the two side molds (3) are respectively bolted to one end of the two bottom corner molds (13), and the other ends of the two bottom corner molds (13) are respectively hinged to both ends of the bottom mold (12); The top mold (1) is connected to the top of the full-ring template gantry assembly (4) via hydraulic support rods; the two side molds (3) are connected to the upper part of the side columns of the full-ring template gantry assembly (4) via hydraulic support rods; the two bottom corner molds (13) are connected to the lower part of the side columns of the full-ring template gantry assembly (4) via hydraulic support rods; the bottom mold (12) is located below the main bridge (10) of the trestle bridge and is fixedly connected to the full-ring template gantry assembly (4).

3. The construction process for casting the double-layer well wall of a frozen inclined shaft according to claim 2, characterized in that, Along the cross-sectional direction of the frozen inclined shaft: the bottom corner mold (13) is an "L"-shaped structure integrally formed by the longitudinal bottom corner mold (131) and the transverse bottom corner mold (132). The longitudinal bottom corner mold (131) and the side mold (3) are connected at an angle, and the angled connection direction is from the side wall of the frozen inclined shaft to the top wall. The transverse bottom corner mold (132) is hinged to the bottom mold (12).

4. The construction process for pouring double-layer well walls in a frozen inclined shaft according to claim 3, characterized in that, The hydraulic support rod connecting the top mold (1) and the top of the full-ring template gantry assembly (4) is the top mold lifting cylinder (2); the hydraulic support rod connecting the side mold (3) and the upper part of the side column of the full-ring template gantry assembly (4) is the side mold cylinder (5); the hydraulic support rod connecting the bottom corner mold (13) and the lower part of the side column of the full-ring template gantry assembly (4) is the bottom corner mold cylinder (6).

5. The construction process for pouring double-layer well walls in a frozen inclined shaft according to claim 4, characterized in that, It also includes a first screw jack (14) and a second screw jack (15); the two ends of the first screw jack (14) are respectively installed on the top mold (1) and the full ring template gantry assembly (4), and the second screw jack (15) is respectively installed on the side mold (3) and the full ring template gantry assembly (4).

6. The construction process for pouring double-layer well walls in a frozen inclined shaft according to claim 1, characterized in that, The stepping template trolley includes a gantry assembly (27), a top mold (1), a side mold (3), a stepping base (21), a hydraulic tie rod (22), a lifting cylinder (25), and a translating base (29). The top mold (1) is mounted on the top of the gantry assembly (27) via a top mold frame (26), and the side mold (3) is connected to the side column of the gantry assembly (27) via a side mold hydraulic support rod. The top mold (1) and the side mold (3) are hinged. The side column of the gantry assembly (27) is mounted on the gantry. The bottom end of the side column of the gantry assembly (27) passes through the bottom beam (20) and is fixedly connected to the translation base (29); a lifting cylinder (25) is installed on the side column of the gantry assembly (27), and the side column of the gantry assembly (27) is raised or lowered relative to the bottom beam (20) by the lifting cylinder (25), and the translation base (29) is raised or lowered relative to the bottom beam (20); The stepping base (21) is mounted on the lower surface of the gantry bottom beam (20) via a slide rail, and the stepping base (21) can slide along the slide rail, which extends along the longitudinal direction of the gantry bottom beam (20). The stepping base (21) includes a forward base (211), a follower base (212), and a connecting rod (213). The forward base (211) and the follower base (212) are fixedly connected by the connecting rod (213), and the connecting rod (213) extends along the longitudinal direction of the gantry bottom beam (20). The follower base (212) and the forward base (211) are sequentially mounted on the lower surface of the gantry bottom beam (20) via slide rails along the forward direction of the stepping template trolley. One end of the hydraulic pull rod (22) is fixedly mounted on the lower surface of the gantry bottom beam (20) adjacent to the follower base (212), and the other end is fixedly connected to the forward base (211).

7. The construction process for casting the double-layer well wall of a frozen inclined shaft according to claim 6, characterized in that, A top mold lifting cylinder is installed on the top mold frame (26), and the lifting of the top mold (1) is controlled by the top mold lifting cylinder; the top mold (1) is provided with grouting holes (30); the side mold hydraulic support rod connecting the side mold (3) and the side column of the gantry assembly (27) is the side mold cylinder (5); the side mold (3) is integrally formed by the top side mold (301) and the side side mold (302), the top side mold (301) is hinged to the top mold (1), and a support rod is provided at one end of the side mold (302); the top side mold (301) A side mold through beam (28) is installed on the top side mold (301) and the upper part of the side column of the gantry assembly (27), respectively. A lateral screw (31) is installed on the side mold (302) and the two ends of the lateral screw (31) are fixedly connected to the lower part of the side column of the side mold (302) and the side column of the gantry assembly (27), respectively. A ground screw (23) is installed on the lower surface of the bottom beam (20) of the gantry, and the free end of the ground screw (23) faces the bottom plate of the frozen inclined shaft.

8. The construction process for casting the double-layer well wall of a frozen inclined shaft according to claim 7, characterized in that, The method for pouring the outer wall of a frozen inclined shaft using the aforementioned step-type template trolley is as follows: During the pouring of the outer well wall, the top mold (1) and the side mold (3) of the stepping template trolley are supported by the lifting cylinder (25) and the side mold cylinder (5); and the supported template is reinforced by the side mold through beam (28), the lateral screw (31) and the ground screw (23); after the formwork is supported, the concrete of the outer well wall is poured. After the outer well wall concrete has been poured for 12-16 hours, the step-type formwork trolley is demolded. After demolding, the stepping template trolley is moved. During the movement, the stepping base (21) and the translation base (29) are alternately stepped forward and landed to achieve forward movement. When the stepping base (21) steps forward, the translation base (29) is supported on the bottom plate of the outer wall of the frozen inclined shaft by controlling the lifting cylinder (25). At this time, the stepping base (21) is separated from the bottom plate of the outer wall. The stepping base (21) is pushed forward along the longitudinal direction of the gantry frame bottom beam (20) by controlling the extension of the hydraulic rod (22). Then, the translation base (29) is lifted up and separated from the bottom plate of the outer wall by controlling the lifting cylinder (25). At this time, the stepping base (21) is supported on the bottom plate of the outer wall. Then, the gantry frame assembly (27) is pulled forward by controlling the hydraulic rod (22).

Images