70results about How to "Facilitate mechanized construction" patented technology

The invention relates to the technical field of railway tunnel construction, specifically a digging method of IV and V-class surrounding rock railway tunnel with large cross section, aiming to solve the problems of the existing railway tunnel digging method including narrow operation space, low work efficiency, inflexible construction method, instable construction progress, high deformation potential of surrounding rock, and inconvenient operation. The method comprises performing leading support, digging arc-shaped pilot tunnel and preserving core soil; staggeredly digging left / right side walls of middle sidestep and preserving core soil; staggeredly digging left / right side walls of lower sidestep and preserving core soil; sequentially digging upper, middle and lower sidesteps and preserving core soil; and digging inverted arch and carrying out preliminary support. The invention has large construction space and high work efficiency, and can perform multi-job parallel operation. When the geologic conditions are changed, the invention can be flexibly and timely converted to other construction method. Preservation of core soil and left / right staggeredly digging are helpful to the stability of the digging working face. When the surrounding rock has large deformation, the invention can adjust closure time as soon as possible under the prerequisite of assuring safety and meeting requirements of clearance cross section.

The invention discloses barite anti-radiation pump concrete. The concrete comprises the following components: cement, water, barite powder, barite sand, barite, synergist and admixture according to a ratio of [340-450]:[110-170]:[75-150]:[1000-1400]:[1800-2000]:[2-4]:[7-19]. According to selection of raw materials and design of the ratio, the anti-radiation concrete which is high in density and high in liquidity and can be used for pumping is obtained.

The present invention relates to the art of railway tunnel construction technology, in particular to a brim-type clip portal construction method of an oval platform of a railway large cross-section tunnel, which solves the problems of the simple separated template technology, such as complicated template installation, the large deviation of structural size and many construction joints. (1) an internal mode, an external mold and an end mold of the brim are manufactured; (2) the hookup lines of the upper mouth and the lower mouth of the internal mold and the external mold are confirmed; (3) the internal mold is arranged according to the hookup lines of the upper mouth and the lower mouth; (4) a brim reinforcing steel bar is colligated; (5) the external mold of the brim is arranged according to the hookup lines of the upper mouth and the lower mouth; (6) the hookup control line of the end mold of the brim is confirmed and then an alternative installation method is adopted; (7) a brim concrete is symmetrically poured. The present invention has the advantages of convenient mechanical construction, small labor investment, multi-faceted parallel operation, simple template installation, high work efficiency and less deviation of structural size, thus ensuring the smooth and pleasing appearance and size; one-time pouring and less construction joints, thus strengthening the waterproof performance of the bright door and the portal.

The invention discloses a draining and salt-removing method for a newly-ploughed salinized farmland, comprising the following steps of: making a simple farmland concealed pipe by utilizing a building PVC (Poly Vinyl Chloride) sewer pipe, uniformly drilling holes with the diameter of 3mm on the wall of a 100mm plastic sewer pipe by the punching rate of 75 percent, coating two to three layers of crude chemical fiber outside the wall of the pipe, and strapping with plastic ropes; digging several rows of concealed pipe ditches in the newly-ploughed salinized farmland, wherein the depth of the concealed pipe ditches is 1.5-2.0m, the bottom width is 30cm and the specification of the side slope is 1:0.5; paving plastic weaved cloth with the width of 40cm at the bottoms of the ditches, paving sand gravel with the thickness of 15cm on the plastic weaved cloth, paving a coated concealed pipe, paving and spreading sand gravel with the thickness of 15-20cm at the surrounding and the upper part of the concealed pipe, paving the plastic weaved cloth with the width of 40cm on the sand gravel and refilling. The invention mainly solves the technical problem of draining by the concealed pipe in the newly-ploughed salinized farmland in aired regions and has a wide application value on the aspects of prevention and control of salinization and secondary salinizaiton of farmland in the dried regions, reformation and utilization of the farmland in the dried regions as well as prevention and control of desertification.

The invention provides interior wall plastering mortar, which is prepared by mixing the following components in part by weight: 30 to 35 parts of ordinary Portland cement, 4 to 5 parts of hydrated lime, 5 to 10 parts of light aggregate, 50 to 60 parts of heavy aggregate, and 1.0 part of C-type composite auxiliary, wherein the light aggregate is an inorganic vitrified hollow cellular material of which the fineness is lower than 100 meshes; the heavy aggregate is ordinary river sand; and the C-type composite auxiliary is sold by Guangzhou Hecheng Trading Company. The construction method for the interior wall plastering mortar comprises the following steps: diluting the light energy-saving interior wall plastering mortar with water accounting for 30 to 50 percent of the weight of the mortar; and mechanically or manually stirring the diluted mortar until the mortar is mixed uniformly to achieve the viscosity suitable for mechanical spraying or manual construction. Therefore, the mortar can be sprayed mechanically or constructed manually. The interior wall plastering mortar has light weight and energy conservation, can prevent hollowness, cracking and falling off by being matched with a light wall body, can effectively reduce cracking of the mortar, ensures the quality of construction work, has the advantages of heat insulation and noise reduction, low cost of unit area, good grain composition, good peaceability, mechanical construction contribution and simple process.

The invention discloses high-performance lithium slag pump concrete. The proportion of mixture of the concrete is cement:water:mineral powder:fly ash:lithium slag:sand:gravel:synergist: additive being (340-520):(165-200):(0-50):(0-50):(40-150):(700-850):(1,000-1,100):(2-3.5):(7-12) according to the component unit of kg / m<3>. By means of selection of the raw materials and design of proportioning, the high-performance lithium slag concrete which is good in working performance, mechanical performance and durability and can be used for pumping is obtained.

The invention discloses a shallow mud foundation treatment method. The method includes: zoning a site to be treated; laying drain boards in a soft soil layer from top to bottom by a floating raft; connecting the ends and middle of the drain boards to a tube drainage system through tube plate connectors; connecting the upper end of the tube drainage system to a vacuum unit; laying woven fabric, geogrid, nonwoven geotextile and seal film on a mud surface from top to bottom; performing vacuum preloading and unloading after requirements are met. The shallow mud foundation treatment method has the advantages that construction period is shortened greatly, vacuum transmission is effective, using sand cushions is avoided, and deformation of the drain boards is reduced greatly.

Disclosed is a large-span subway station underground excavation construction method for a hard rock stratum. The large-span subway station underground excavation construction method for the hard rock stratum is used for effectively reducing the excavation construction risk and improving the excavation construction efficiency. The large-span subway station underground excavation construction method for the hard rock stratum comprises the following steps that the arch portion middle of a station is divided into two steps to be excavated, a tunnel arch portion middle upper step is excavated, and an initial support arch cover of the tunnel arch portion middle is constructed; a tunnel arch portion middle lower step is excavated; a tunnel arch portion left side portion and a tunnel arch portion right side portion are excavated, feet-lock bolts are constructed at the arch foot positions, the initial support arch cover on the arch top is lengthened through connection, and construction of the initial support arch cover is accomplished; a rock mass arranged below the station is excavated in a slot broaching mode under the protection action of the initial support arch cover, nine portions including upper steps on the left portion, the middle portion and the right portion, middle steps on the left portion, the middle portion and the right portion and lower steps on the left portion, the middle portion and the right portion are excavated, and side wall initial supports of corresponding sections are constructed until the rock mass is excavated to the bottom; and a station body structure is sequentially constructed from bottom to top, and station construction is accomplished.

The invention relates to a modular biological permeable dam and a construction method thereof. The modular biological permeable dam comprises a dam structure formed by piling a plurality of single net box bodies, and each single net box body is of a net-shaped box structure formed by weaving a steel wire through a mechanical technology. Each single net box body is filled with dam stone with the particle size of 8-25 cm and a microbial carrier with the particle size of 6-10 cm, wherein the middle part of the single net box body is filled with the microbial carrier, the part around the microbial carrier is filled with the dam stone, and the filling volume of the microbial carrier is 20-35% the overall volume of the single net box body. The modular biological permeable dam has the function of a common dam and also can purify river water; besides, the modular biological permeable dam is convenient and fast to install, easy to dissemble and assemble, firm in structure, wide in application range and recyclable.

The invention relates to light-weight and energy-saving plastering mortar, which is prepared by mixing the following components in part by weight: 30 to 40 parts of ordinary Portland cement, 2 to 4 parts of hydrated lime, 10 to 20 parts of light aggregate, 40 to 50 parts of heavy aggregate and 1.0 part of compound aid, wherein the light aggregate is an inorganic vitrified hollow microporous material of which the fineness is below 100 meshes; and the heavy aggregate is aeolian sand. During construction, the light-weight and energy-saving plastering mortar is diluted by water added in an amountwhich is 30 to 50 percent based on the weight of the light-weight and energy-saving plastering mortar, and is stirred and mixed mechanically or manually and uniformly until the plastering mortar has the suitable viscosity, and then mechanical spraying or manual construction Is performed. According to the concept of light weight and eco-environmental protection, the light-weight and energy-saving plastering mortar is made light by adopting the inorganic vitrified hollow microporous material, and is matched with the primary elastic modulus of a light-weight wall body to reduce coefficients of heat conductivity and reduce the thermal bridge effect, so the light-weight and energy-saving plastering mortar prevents hollowing, cracking and shedding, insulates heat and reduces noise, and is favorable for mechanized construction. The aeolian sand is used as aggregates, so the plastering mortar has excellent grading distribution and has the prominent three-dimensional texture; and the special compound aid is adopted to improve the peaceability of the mortar to achieve the excellent construction effect.

The invention discloses a circularly progressively rolling type channel lining machine which comprises support rails, a rolling device and a framework. The circularly progressively rolling type channel lining machine is characterized in that two end transverse beams are connected with the two side support rails; slide transverse beams are slidably connected onto two side slide rails, and the framework is connected onto the slide transverse beams; a channel shaping bulldozing plate, a collecting hopper, a joint cutting device and the rolling device are sequentially assembled on the framework; the collecting hopper is provided with a front collecting hopper and a rear collecting hopper, a leaking opening is formed in the bottom of the front collecting hopper, and leaking openings are formed in two sides of the rear collecting hopper; side connecting plates and bottom connecting plates are connected onto the framework, side vibrating rollers are connected onto the side connecting plates, and bottom vibrating rollers are connected onto the bottom connecting plates; flexible transmission racks are wound on driving and driven gears, and a point of each flexible transmission rack is fixedly connected with the framework. The circularly progressively rolling type channel lining machine has the advantages that continuous channel lining construction can be carried out via rolling operation, so that the construction speed can be increased, and the channel concrete construction quality and the durability of a project can be improved; the circularly progressively rolling type channel lining machine is simple in operation, labor can be saved, the cost of the project can be lowered, and disruption and pollution to surrounding environments can be reduced.

Disclosed is a fast construction method for controlling extruded type deformation of a tunnel. The fast construction means that relative to the construction speed or construction efficiency of arranging a common temporary transverse support, a foot locking anchor rod and the like, the speed is increased or the efficiency is improved, the fast construction is suitable for operation spaces of fractional construction of a tunnel bench cut method, primary supporting steel arch frame and arch foot deformation can be effectively controlled, so that the construction efficiency is improved advantageously, and the construction safety is ensured advantageously. The fast construction method for controlling extruded type deformation of the tunnel is characterized in that the fast construction method comprises the following steps that (1), in the fractional construction of the tunnel bench cut method, arch foot basal troughs are dug out from the left side and the right side of a previous step; and (2), arch foot deformation control devices are arranged in the arch foot basal troughs, when the arch foot deformation control devices dig downwards an adjacent next step, and hanging arm supports capable of being disassembled and assembled are formed in the a plurality arch feet longitudinally distributed in same level primary supporting.

The light energy-saving heat insulating wall material is produced with light aggregate in 1.2-2.6 wt%, gelating material in 72-76 wt% and sand in 22-26 wt%, as well as water in 35-88 wt% of gelating material, bulking agent in 13 wt% of gelating material and water reducing agent in 1 wt% of gelating material. The light energy-saving heat insulating wall material has the advantages of saving in land, low power consumption, light weight, easy construction, high heat insulating performance, etc. and may be used in network structure building system and non-bearing wall building system.

The invention provides composite mortar and a manufacturing method thereof, and belongs to the field of production of building materials. In the composited mortar, cement, mineral sand, coal ash and glass beads are taken as aggregates, and carboxymethyl cellulose sodium, wood fibers, gelatine powder, a water-retaining agent, a water reducing agent and a water repellent are taken as additives. The manufacturing method comprises the following steps: first, sequentially putting cement, additives, glass beads and coal ash into a reaction kettle, premixing the mixture for a certain time, putting an obtained substance and mineral sand into a stirrer, stirring the mixture and cooling, so as to obtain the composite mortar. The invention provides the composite mortar and the manufacturing method thereof; the composite mortar has the advantages of being safe and non-toxic and reducing energy consumption, is good in peaceability, crack resistance, thermal insulation and waterproofing, high in strength, corrosion resistance and adhesion, light in weight and convenient in construction, is beneficial to mechanical construction, and has the characteristics of saving working hours and lowering construction cost.

The invention discloses a wall building material, comprising the following components in parts by weight: 50-80 parts of ceramic polishing residue, 0-30 parts of feldspar, 2-10 parts of calcined soapstone, 10-20 parts of red mud, 0-10 parts of lithium feldspar, 0-15 parts of dickite, 0.5-2 parts of silicon carbide, 1.5-3 parts of stabilizer and 40-50 parts of water. The invention also provides a preparation method of the wall building material. The method comprises the following steps: ball-milling, drying, loading into a cellar, sintering and cutting. The wall building material disclosed by the invention is light in dead load, good in anti-seismic effect, high in thermal insulation properties and good in sound insulation.

The invention belongs to the technical field of agricultural irrigation and particularly relates to a water-saving irrigation pipeline and a construction method thereof. The water-saving irrigation pipeline comprises a spodosol packing layer which is arranged in a foundation trench and a composite flexible pipe which is fixedly arranged in the spodosol packing layer, wherein the composite flexible pipe comprises a flexible pipe base layer, a PVC (Polyvinyl Chloride) coated layer and a PE (Poly Ethylene) thin-film layer from outside to inside. The construction method comprises the steps of material selection, foundation trench excavation, spodosol slotting, pipe laying, pipeline inspection, water-immersion compacting and the like. According to the water-saving irrigation pipeline, the problems such as pipeline breakage, water exclusion and operation difficulty which are brought by the structure and construction problems in the prior art are solved; the water-saving irrigation pipeline has the advantages of water-saving property, energy-saving property, land-saving property, simplicity and practicability in construction, short construction period and the like, and can be popularized in a large area, so that a new way is provided for saving water for the agriculture in China.

The invention provides a comprehensive tunnel drainage, precipitation and pressure reduction construction method, relates to an in-tunnel drainage, ground precipitation and comprehensive pressure reduction construction method for a water and mud burst segment of a tertiary system sand shale tunnel and is mainly designed to solve the problems that an existing tunnel is prone to deformation, collapse and even water burst and mud burst in the tertiary system sand shale construction process. Ground precipitation wells are drilled at the positions, eight meters away from the side lines on the two sides, of a ground-direction positive hole, a flat guide hole is formed near the ground-direction positive hole, a drainage hole is formed in the inclined upper direction of the ground-direction positive hole relative to the flat guide hole, tunnel substrate precipitation wells are drilled in both the substrate of the ground-direction positive hole and the substrate of the flat guide hole, a plurality of inclined drainage holes are formed above the inclined front portion of a vault of the ground-direction positive hole, a positive hole vertical drainage hole is formed above the vault of the ground-direction positive hole, and a flat guide hole vertical drainage hole is further formed above the vault of the flat guide hole. The comprehensive tunnel drainage, precipitation and pressure reduction construction method has the advantages that geological disasters such as collapse, deformation, water burst and mud burst are avoided, and tunnel construction safety can be guaranteed.

The invention provides a design method for an agricultural drain concealed conduit with an externally coated filter material. The method is integrating a filter material layer and a drain concealed conduit, so as to form an integral finished product, wherein the filter material layer comprises a straw rope layer and a geotextile layer. The method comprises the following steps: winding a straw rope tightly on the outer wall of the drain concealed conduit, so as to form a straw coated layer; coating geotextile on the straw rope; and winding a nylon rope on the geotextile layer, so as to ensure that the geotextile and the part in the geotextile are integrated without loosing. The diameter of the straw rope is 2 to 3 cm; and the geotextile comprises cloth strips which are 20 cm in width. The invention has the advantages that the water seepage capability of the passage of the agricultural drain concealed conduit is improved; the drain effect of the agricultural drain concealed conduit is improved; the mechanized construction is more convenient; and the burying process of the agricultural drain concealed conduit is simplified.

The invention provides an ecological slope protection method for reinforcing slope soil by combining a permeable retaining wall and a penetration type embedded steel bar belt. The method is characterized in that a penetration type exploration and construction two-in-one method is utilized, anti-sliding short piles are arranged to the designed depth to reinforce a potential deep sliding surface, the embedded steel bar belt (hydrophilic reinforced belt) is connected with the anti-sliding short piles in a pulling mode, the hydrophilic reinforced belt is equivalent to increase the root length (imitation rooting) of slope plants, the defect that the slope soil cannot be effectively reinforced due to the fact that the root system of a common plant is short is overcome, and reinforcing and ecological protection of the deep slope soil and the shallow slope soil can be effectively realized by combining dense backfill soil or self-silting soil around the embedded steel bar belt. A slope water storage and drainage ditch is manufactured by laying waterproof films or concrete plates on the side surface and the bottom of the ditch, filling the ditch with permeable gravel and laying permeable concrete on the top surface of the ditch, so that rainfall can be smoothly discharged into a guide drainage ditch in the slope direction after entering the water storage and drainage ditch, and further discharged to a drainage ditch at the slope toe. The permeable retaining wall at the slope toe can replace a stone-laying retaining wall which is frequently used at present and is prone to being blocked, so that the anti-sliding force and the drainage performance of the slope soil are improved, and the problems that the soil arch effect is invalid due to the fact that the strength of the slope soilis reduced after rainfall, and the slope toe is unstable due to the fact that drainage is not smooth after a drainage hole of an existing stone-laying retaining wall is blocked are solved.

The invention discloses a rigid connecting piece steel bridge deck pavement structure and a pavement method. The pavement structure comprises a top plate, longitudinal webs and transverse partition plates, wherein the longitudinal webs and the transverse partition plates are in orthogonal connection with the bottom surface of the top plate; the top surface of the top plate is paved with a bridge deck pavement layer and provided with connecting pieces located in the bridge deck pavement layer; and the connecting pieces are easy to construct and high in shear bearing capacity, uplift bearing capacity and anti-stripping capacity. According to the pavement method, the connecting pieces composed of steel plates, left trough plates and right trough plates are adopted, construction is convenient and quick, operation is easy and convenient, an integral pavement layer formed by paving a steel fiber reinforced concrete layer and an asphalt concrete layer is formed, the tensile capacity is improved, and the thickness is increased; and the tensile stress and strain resistance of the surface of the pavement layer can be effectively reduced, and thus, the cracking problem of the surface of the pavement layer can be effectively solved.

The invention discloses a construction method for a weak surrounding rock section of a short-step super-large-section tunnel, and belongs to the technical field of tunnel construction. The construction method comprises the following steps that S1, a top arc-shaped pilot tunnel is excavated; s2, middle steps on the two sides are excavated left and right; s3, excavating lower steps on the left side and the right side; s4, core soil is excavated; and S5, tunnel bottom excavation and inverted arch supporting are carried out. The construction method is high in safety, fast in construction progress, short in construction period, stable in supporting structure, short in forming time of each whole ring, large in construction space, convenient for mechanical deslagging, fast in construction effect and capable of effectively shortening the closed ring forming time.

The invention discloses a barite anti-radiation pumping concrete. The mixing ratio of the concrete according to the weight part is: cement: water: barite powder: barite sand: barite: synergist: admixture = [340 ~450]: [110~170]: [75~150]: [1000~1400]: [1800~2000]: [2~4]: [7~19]. Through the selection of raw materials and the design of the ratio, a radiation-resistant concrete with high density and good fluidity that can be used for pumping is obtained.

The invention discloses a ceiling putty leveling troweling machine, which comprises a lifting motor, a chain wheel, a chain, a scraper driving motor, a troweling knife rail, an automatic lifting inductive switch, a vertical rod, a base and the like. The lifting motor and the vertical rod are mounted on the base, and an output shaft of the lifting motor is connected with a screw; a nut fixed to thevertical rod and the screw form a spiral transmission pair, and the vertical rod is connected with a steering gear compass; a travel switch is mounted on the vertical rod, and a support is connectedto the upper part of the vertical rod; an output shaft of the scraper driving motor is connected with a chain wheel rotary shaft, and the chain wheel is mounted on the chain wheel rotary shaft; the chain wheel rotary shaft is supported on a skeleton, the chain wheel rotary shaft drives the chain wheel to rotate, and the chain wheel drives the chain to rotate; and a plurality of troweling knives fixed to the chain rotate simultaneously, the multiple troweling knives stabilize traveling tracks of the troweling knives through the troweling knife rail, and the automatic lifting inductive switch capable of setting the height from the troweling knives to a ceiling is mounted on the skeleton. The ceiling putty leveling troweling machine is high in automation degree, free of pollution, easy to operate, small in energy consumption, capable of automatically ascending and descending, and high in efficiency.

The invention discloses an organic fiber PVC (Polyvinyl Chloride) multilayered composite flexible pipe and a preparation method thereof, aiming at solving the technical problems of a pipe for agricultural irrigation in the prior art that the corrosion resistance is poor, the toughness and the tensile strength are poor, the anti-cracking performance and the anti-freezing performance are poor, and the price is high. The organic fiber PVC multilayered composite flexible pipe comprises a pipe body, wherein a polyvinyl chloride plastic coating layer is arranged on the inner wall of the pipe body, and a composite plastic film layer is arranged on the plastic coating layer; the pipe body is made of the following raw materials in parts by weight: 28-33 parts of polyacrylonitrile fibers, 8-12 parts of liquid-state silica gel and 3-7 parts of liquid-state PVC stabilizing agent. The pipe has very remarkable advantages in the aspects of cracking strength, acid and alkali resistance, low-temperature resistance and cracking elongation and is a very ideal irrigation and water conveying pipe; mechanized construction is convenient to realize and the working efficiency is improved; the pipe is convenient to operate and maintain in a water conveying and irrigation process and is convenient to repair, and the reliable water supply is ensured.

The invention discloses a slide-resistant pile and geogrid combined damaged mountain repair method and structure, and belongs to the technical field of damaged mountain environmental government. A repaired mountain is formed through soil filling based on an original damaged mountain, a side slope and a sliding face exit after filling, multiple rows of slide-resistant piles are arranged on the middle and front portions of the side slope, reinforced concrete coupling beams are arranged at the tops of the slide-resistant piles, the slide-resistant piles are inserted into the lower portion of thesliding face of the side slope and embedded into stable original bed rock, and horizontally-laid geogrid reinforcing areas are arranged on the top of the filled mountain. By means of the structure andthe method, the slide-resistant piles and geogrids are combined to resist sliding to ensure overall stability of the mountain. A supporting structure which combines a support and reinforcement ribs and is easy to construct and high in slide resistance is formed on the side slope, and the overall side-resistant effect is achieved on the filled mountain.

The invention discloses a steep slope high-filling roadbed structure adopting a high-density EPS filler. The steep slope high-filling roadbed structure comprises short piles, cross beams, stand columns, an enlarged foundation, longitudinal connecting beams, a bearing plate, breast boards, a light filler, a sand cushion layer, a pavement slab, an anti-collision guardrail and side ditches. The self-weight and soil side pressure of a roadbed filling material are reduced, the utilization efficiency of a supporting structure material is improved, and therefore, the roadbed structure is more reasonable in stress, the structural stability of the roadbed structure is remarkably improved, the mass of the supporting structure of the roadbed structure is effectively reduced, and the problem of roadbed structure design mainly based on fill in a steep-slope high-fill roadbed is effectively solved to a certain extent. The steep slope high-filling roadbed structure is good in adaptability to mountainsteep slope terrains, safe and reliable in structure, moderate in construction difficulty and good in environmental and economic benefits, provides great convenience for mountainous engineering construction, and has popularization and application value in the technical field of highway engineering.

The invention provides a rotary-jet anchor cable composite foundation and belongs to the field of electric transmission line foundation engineering. The composite foundation comprises a top foundationand a pulling cable; an open hole is formed in the center of the top foundation; one end of the pulling cable is fixed to the open hole; the other end of the pulling cable extends towards the deep position of soil and is fixedly connected with an anchor head provided with a conical head; a rotary-jet pile formed through injection into the soil layer with a high-pressure jet grouting method is adopted between the anchor head and the bottom surface of the top foundation; and the anchor head, the pulling cable and the top foundation are combined into one by the aid of the rotary-jet pile. The composite foundation is simple and stable in structure, mechanical construction is adopted mainly, and construction operations can be reduced correspondingly, so that the construction difficulty and cost are reduced while the upwards-pulling requirement is met, and the influence on the environment is reduced.