Green municipal drainage pipeline construction method

Abstract

The invention discloses a green municipal drainage pipeline construction method. The method comprises the steps that construction preparation is conducted; mounting a fence; breaking a pavement structure layer; constructing a supporting structure; detecting the bearing capacity of the foundation; installing and backfilling a pipeline and a well seat; and recovering the pavement. The method is fixed in operation procedure, suitable for municipal pipeline transformation construction of various pavement structures and foundation soil bodies, high in planning, controllable in construction process quality and low in safety risk.

Description

Technical Field

[0001] The invention relates to the field of civil engineering, and in particular to a green municipal drainage pipeline construction method. Background Art

[0002] In order to fully implement the concept of green and low-carbon development, improve the level of ecological civilization construction, and accelerate the construction of a new pattern of green and low-carbon development, Yunnan Province has vigorously promoted the transformation of urban and rural rainwater and sewage diversion. The construction sites of urban and rural rainwater and sewage diversion are scattered, and traffic interference is large. The traditional construction method has many procedures, long construction time, and no unified construction standards, which makes it impossible to dig trenches again, and there are many quality hazards and high safety risks during the construction process. Summary of the invention

[0003] The purpose of the present invention is to provide a green municipal drainage pipeline construction method, which has a fixed operation procedure and is suitable for municipal pipeline reconstruction construction of various pavement structures and foundation soils. It has strong planning, controllable construction process quality and low safety risks.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0005] A green municipal drainage pipeline construction method, the method comprising the following steps:

[0006] Step 1) Construction preparation;

[0007] Step 2) Fence installation: Install construction fences to isolate the construction area from the traffic area;

[0008] Step 3) Demolishing the pavement structure layer: digging pavement cuts in the construction area between the construction fences, and digging out a trapezoidal pavement structure excavation portion between the pavement cuts;

[0009] Step 4) Support structure construction: Install the guide frame in the excavated part of the pavement structure, then drive the Larsen steel sheet pile into the excavated part of the pavement structure, and then carry out earth excavation;

[0010] Step 5) Testing the bearing capacity of the foundation: Conduct a light penetration test to test the bearing capacity of the foundation;

[0011] Step 6) Pipeline, well seat installation and backfilling:

[0012] The pipeline and well seat are installed in the area between the Larsen steel sheet piles. After installation, backfill is carried out, and then the supporting purlins are removed. The Larsen steel sheet piles are pulled out and filled with sand;

[0013] Step 7) Road surface restoration: After backfilling, the excavated part of the road surface structure is sequentially provided with a pipeline backfill layer, a pipeline backfill upper layer, a road surface cushion layer, and a road surface base layer from bottom to top; traffic is opened after the asphalt concrete of the road surface has cooled to the required temperature.

[0014] Further: in said step 1), construction preparation includes construction technology preparation, construction site preparation, construction material preparation, and construction test preparation.

[0015] Further: in the step 2), the construction fence adopts modular columns, baffles, and diagonal braces, which are assembled and fixed with cone-tail screws, and the columns and diagonal braces are fixed to the road surface with expansion bolts.

[0016] Furthermore: in the step 3), the excavated construction waste is loaded onto trucks for transportation, crushed and processed, and then sieved and classified to be used as backfill material around the pipeline.

[0017] Further: in the step 4), after the Larsen steel sheet piles are arranged in rows, corbels and purlins are welded on the Larsen steel sheet piles, and steel supports are arranged between the purlins.

[0018] Further: in the step 6), when the pipeline is installed, a pipeline foundation treatment layer is arranged at the lower part between the Larsen steel sheet piles, the pipeline foundation treatment layer is used to install the prefabricated pipeline well seat, and a pipeline backfill layer is arranged between the Larsen steel sheet piles outside the pipeline well seat.

[0019] Further: in the step 6), when the well seat is installed: a prefabricated well seat non-standard section is arranged at the lower part between the Larsen steel sheet piles, a prefabricated well seat standard section is arranged on the prefabricated well seat non-standard section, a prefabricated concrete well cover is arranged on the prefabricated well seat standard section, and the first layer of well seat perimeter backfill, the second layer of well seat perimeter backfill, and the third layer of well seat perimeter backfill are arranged in sequence from bottom to top between the prefabricated well seat non-standard section, the prefabricated well seat standard section and the Larsen steel sheet piles.

[0020] Further: in the step 4), during earth excavation, an auxiliary truss group is placed on the construction area between the construction fences between the cuts of the excavated pavement outside the excavated part of the pavement structure, and the roller excavation machinery uses the auxiliary truss group to excavate the soil within the processing depth at the top of the trench and fill the replacement material in layers.

[0021] Further: In step 6), after the installation of the pipeline and the well seat, a water-tightness test is carried out, and backfilling is carried out after the water-tightness test. When the concrete strength of the flow channel in the water-tightness test section exceeds 2.5MPa, an air bag is inserted into the pipe outside the water-tightness test section to inflate, and water is injected, observed, and recorded.

[0022] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0023] (1) This construction method uses construction fencing to isolate the construction area from the traffic area, effectively controlling the mutual impact between construction and traffic. The road surface cutting method effectively controls the scope of road surface demolition and reduces damage to the existing road surface. The Larsen steel sheet pile is used to reduce the trench excavation width, prevent trench collapse, and speed up the construction progress. The internal steel support is used to apply prestress mechanically to effectively control the deformation of the roadbed and reduce the settlement of the road surface during trench excavation. After the road structure is demolished, the construction waste is first loaded and then the working platform is used to excavate the earth, which effectively solves the problem of the excavator working platform. At the same time, the construction waste is effectively separated from the earth, providing conditions for the recycling and processing of construction waste.

[0024] (2) Prefabricated pipes and well seats are used for installation, and the prefabricated concrete structure accounts for more than 90%. The use of airbags to plug water reduces the difficulty of the water-tightness test and shortens the preparation time for the water-tightness test, providing conditions for the full, segmented, and continuous water-tightness test of the pipeline. The full, segmented, and continuous water-tightness test of the pipeline reduces the risk of pipeline leakage; the test water in the water-tightness test pipeline is repeatedly used in the test section by a pump, saving water.

[0025] (3) Set up a construction waste processing plant to crush and screen the construction waste, and use the processed products as trench backfill materials. Adopt segmented excavation and flow construction to shorten the construction period of each section and the road occupation time, and reduce the impact of construction on traffic.

[0026] (4) The method has a fixed operation procedure and is suitable for municipal pipeline reconstruction construction with various pavement structures and foundation soils. It has strong planning, controllable construction process quality and low safety risks. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a construction flow chart of the present invention.

[0028] Figure 2 It is a schematic diagram of the pavement cutting in the present invention.

[0029] Figure 3 It is a schematic diagram of a part of the pavement structure dug out in the present invention.

[0030] Figure 4 It is a schematic diagram of earth excavation in the present invention.

[0031] Figure 5 This is the first schematic diagram of pipeline installation backfilling in the present invention.

[0032] Figure 6 This is the second schematic diagram of pipeline installation backfilling in the present invention.

[0033] Figure 7 This is the first schematic diagram of the well seat installation and backfilling in the present invention.

[0034] Figure 8 This is the third schematic diagram of pipeline installation backfilling in the present invention.

[0035] Fig. 9 This is the second schematic diagram of the well seat installation and backfilling in the present invention.

[0036] In the figure: 1-construction fence, 2-pavement cutting, 3-excavated part of pavement structure, 4-Larsen steel sheet pile, 5-corbel, 6-purlin, 7-steel support, 8-auxiliary truss group, 9-pipeline foundation treatment layer, 10-pipeline backfill layer, 11-pipeline backfill upper layer, 12-pavement cushion layer, 13-pavement base layer, 14-pavement surface layer, 15-prefabricated well seat non-standard section, 16-prefabricated well seat standard section, 17-prefabricated concrete manhole cover, 18-first layer of backfill around well seat, 19-second layer of backfill around well seat, 20-third layer of backfill around well seat. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0038] A green municipal drainage pipeline construction method comprises the following steps:

[0039] Step 1) Construction preparation

[0040] Step 1.1) Construction technical preparation. Review drawings, hand over design drawings, prepare "Construction Organization Design", and pass the approval and acceptance of construction and supervision units. Before construction, the construction unit should participate in the drawing review organized by the construction unit, accept the design handover of the design unit, review the construction drawings, and raise questions about unclear drawings and drawing contradictions. The design unit will answer them on site, or supplement the drawings and instructions. The construction unit shall prepare the construction organization design based on the construction drawings and available resources, and after internal review and approval by the construction unit, it shall be submitted to the supervision and construction unit for acceptance and approval. If the supervision unit needs to review the procedures and schemes of the construction organization and the selection is unreasonable, and requires the construction unit to modify them, the construction unit shall modify them as required and resubmit them for acceptance and approval.

[0041] Step 1.2) Construction site preparation. Conduct geophysical exploration of underground pipelines and confirm the surrounding environment. Fully understand the geological conditions and underground facilities in the construction area, especially the location and direction of underground pipelines, and prepare a "Protection Plan for Ground Structures and Underground Pipelines" to avoid damaging existing pipelines. Prepare a "Traffic Guidance Plan" to reduce the mutual impact between construction and traffic. Based on the underground pipeline information provided by the construction unit, use detection equipment for on-site verification. If the pipeline position is accurate, draw position marks at both ends of the pipeline outside the pavement cut line, and write down the main information of the pipeline type, material, and burial depth; if the pipeline position is inaccurate, it should be adjusted in time and reported to the supervision and construction unit; if there is no display in the information and there is doubt on site, draw a doubt mark. According to the on-site review of the pipeline, prepare a "Protection Plan for Ground Structures and Underground Pipelines", and use manual demolition and manual excavation of the pavement structure and earthwork within 1m around the pipeline to avoid damage to the existing pipeline. After the pipeline is excavated, the existing pipeline is protected by hanging, supporting, and wrapping. Divide the construction sections according to the construction scope and construction conditions, and determine the parallel or flow construction sequence of each section. Use tool-type construction fences to isolate the construction area from the traffic area. The construction fence uses modular columns, baffles, and diagonal braces assembled and fixed with cone-tail screws. The columns and diagonal braces are fixed to the road surface with expansion bolts. A temporary double-opening gate is set at the end of the fence, and a duty personnel is arranged to manage the entry and exit of construction vehicles and personnel. A transparent fence is set at the end of the fence as required to reduce the blind spot of traffic vehicles. The installation height of the transparent fence is the same as that of the ordinary fence, and the height of the non-transparent part at the bottom is 900mm. The excavated trenches and pits are enclosed by tool-type railings, and the construction vehicles on the side of the railing are isolated by anti-collision barrels and cone barrels. Anti-collision barrels and cone barrels are placed to isolate the buffer zone, transition zone, and work zone to reduce the impact of construction vehicles on the work surface. Combined with the above content, the "Traffic Guidance Plan" is prepared. After internal review, the supervision unit and the construction unit communicate with the traffic management department based on the "Traffic Guidance Plan". After reaching an agreement with the traffic management department, the supervision unit approves the implementation. This measure effectively controls the mutual impact of construction and traffic.

[0042] Step 1.3) Preparation of construction materials. Prepare a plan for the use of prefabricated components, backfill materials, and turnover materials, and guide the prefabrication plant to prefabricate pipes and well bodies. Prepare a material use plan based on the construction drawings and construction schedule. The plan for the use of backfill materials and turnover materials specifies the material name, material requirements, main characteristics, total planned amount, and detailed usage at each stage. Sort out prefabricated components and related parameters of prefabricated components according to the construction drawings, such as the length, width, height, thickness of the section, concrete strength, steel bar specifications, models, distribution, connection requirements, and the size and position of reserved embedded holes and embedded parts. Determine the list of standard and non-standard components based on the production capacity and existing resources of the prefabrication manufacturer. For example, pipes, covers, and wellbores are designed as standard components according to specifications. The upper part of the well chamber is designed as a standard component according to specifications, and the lower part is designed as a non-standard part. The reserved holes are staggered between the upper and lower parts of the well chamber. At the same time, in order to reduce the total weight of non-standard parts, the dividing line between non-standard parts and standards is moved down as much as possible. Finally, a plan for the use of prefabricated components is prepared, and a production list for prefabricated components is prepared based on the plan. The manufacturer is given instructions and process guidance to produce and maintain prefabricated components in batches.

[0043] Step 1.4 Construction test preparation. According to the construction drawings and construction segment division, prepare the "Water-tightness Test Plan", clarify the organization procedures of the water-tightness test, determine the water-tightness test section, test plugging method, water head height, water consumption and source, and the turnover and transfer method of test water.

[0044] Step 2) Enclosure installation:

[0045] The construction area and the traffic area are separated by construction fence 1. The construction fence 1 is firmly and beautifully installed. The height of construction fence 1 is 2.5m. Construction fence 1 adopts modular columns, baffles, and diagonal braces, which are assembled and fixed with cone-tail screws. The columns and diagonal braces are fixed to the road surface with expansion bolts. A temporary double-opening gate is set at the end of construction fence 1, and a duty personnel is arranged to manage the entry and exit of construction vehicles and personnel. A transparent fence of more than 20m is set at the end of construction fence 1 as required to reduce the blind spot of traffic vehicles. The installation height of the transparent fence is the same as that of the ordinary fence, and the height of the non-transparent part at the bottom is 900mm. Tool-type railings are used to enclose the excavated trenches and pits. Anti-collision barrels and cone barrels are placed on the side of the construction vehicles enclosed by the railings for isolation. In the construction location where the isolation fence cannot be installed, anti-collision barrels and cone barrels are placed to isolate the buffer zone, protection zone, and work zone to reduce the impact of traffic vehicles on the work surface.

[0046] Step 3) Removal of pavement structure layer:

[0047] After the installation of the construction enclosure 1 is completed, the center point of the well chamber is released, and the center line of the pipeline is popped out by marking the center line. The distance is measured outward to pop out the excavation edge line, and the road surface is cut along the excavated road surface 2, and the road surface structure is broken. The road surface structure is excavated between the road surface cut 2 to dig out the trapezoidal road surface structure excavation part 3, and the construction waste is loaded and transported out. It is transported to the recycling processing plant, crushed and processed, and then screened and classified for use.

[0048] Step 3.1) Construction layout. First, lay out the center point of the well chamber on the original road surface, pop up the center line of the pipeline, and pop up the edge line of the trench parallel to the center line of the pipeline. After the construction fence 1 is installed properly and the special on-duty personnel who manage the temporary double-door are on duty, start laying out the lines. Verify that the coordinates and elevation control points handed over by the construction unit meet the construction requirements and handle the handover. According to the well position coordinate table in the construction drawing, lay out the center point of the well chamber and mark it. Pull the engineering line between the center points of adjacent well chambers to ensure that it is tight and straight, mark every 3m, and pop up the center ink line of the pipeline between the two marked points. Determine the trench excavation width based on the pipeline radius, encapsulation thickness, working surface width, and slope width. Every 3m, measure the trench width from the center ink line of the pipeline to both ends and mark it, and draw ink lines on adjacent marked points section by section, and connect the ink lines as the excavation edge line of the pipeline trench. Determine the excavation width of the well chamber location based on the outer surface size of the well chamber, the working surface width, and the slope width. Measure the excavation width from all sides of the well center point and mark them. Draw ink lines on adjacent marked points one by one, and connect the ink lines to form the well chamber excavation edge line.

[0049] Step 3.2) Pavement cutting. Use mechanical cutting to dig the pavement cutting 2 along the edge of the groove, and the depth penetrates the pavement structure. Verify that the ink line of the groove excavation edge is correct and check the mechanical condition of the pavement cutting machine. When cutting the pavement structure, in order to reduce the impact of later crushing on the retained pavement, the cutting depth should not be less than 200mm, and the diameter of the cutting blade should not be less than 500mm. The cutting machine cuts neatly along the ink line. The groove edge cutting should be carried out section by section to avoid long-distance round trips.

[0050] Step 3.3) Road surface demolition. After the groove edge line pavement cutting 2 is completed, a crawler excavator is used to install a crushing head to demolish the pavement structure in time. The crawler machinery is equipped with rubber crawler blocks to reduce the damage to the retained pavement caused by the movement of the machinery. The pavement structure demolition work is closely followed by the groove edge line cutting work, and the pavement is demolished longitudinally from one end to the other single end and horizontally from the middle to both sides. During the demolition process, attention should be paid to the protection of the retained pavement, and the crushing head should be kept at a certain distance from the retained pavement.

[0051] Step 3.4) Process and utilize construction waste. Recycle and process construction waste for use as backfill material. After a section of the pavement structure is demolished, a backhoe is used to dig out the pavement structure from the inside out. The concrete, cement stabilization layer, and gravel construction waste of the pavement structure are loaded and transported as they are dug. During the excavation of the pavement structure, avoid disturbing the earth under the roadbed and mixing the earth with construction waste. The muck truck transports the concrete, cement stabilization layer, and gravel construction waste to the construction waste processing site, where crushers, conveyor belts, and screening equipment are used for crushing and separation. The separated gravel is collected and stacked in the yard. After the pipeline water-tightness test is passed, it is used as backfill material around the pipeline.

[0052] Step 4) Support structure construction:

[0053] When constructing Larsen steel sheet piles, follow the principles of "grooving support, supporting first and then digging, and excavating in layers".

[0054] Step 4.1) Larsen steel sheet piles are inspected and accepted on site. After the pavement structure is demolished and transported away, the construction of Larsen steel sheet piles begins. The material and specifications of the steel sheet piles are verified to meet the bearing capacity requirements of the project. Check whether the material, thickness, width and length parameters of the steel sheet piles meet the design requirements, and accept the relevant material certificates and quality assurance certificates. Check the appearance quality of the steel sheet piles, whether the surface of the steel sheet piles is flat, free of cracks, rust, and damage defects, and ensure that the appearance quality of the steel sheet piles meets the relevant standard requirements. The steel sheet piles are connected with steel sheet pile locks. Check whether the connection is firm, free of defects, and meets the relevant design requirements. Select the unqualified piles, calibrate them, and repair them by welding for standby use. If they cannot be repaired, return them to the leasing unit.

[0055] Step 4.2) Inspection of vibratory pile hammer. Check and confirm that the bolts and pins of each part of the vibratory pile hammer are firmly connected, and the springs, shafts and guide sleeves of the vibration reduction device are intact. Check the tightness of each transmission belt. If the tightness does not meet the requirements, it should be adjusted in time. Check the tooth shape of the clamping plate. When the tooth wear exceeds 4mm, it should be replaced or repaired by surfacing. Check and confirm that the guide device of the vibratory pile hammer is firm and reliable. The matching clearance between the guide device and the column guide rail should comply with the provisions of the instruction manual. The crane hook that suspends the vibratory pile hammer should have a protective device to prevent loosening.

[0056] Step 4.3) Larsen steel sheet pile is driven in. Before the formal injection, the lime line is marked. When injecting, first install the guide frame, apply butter inside the steel sheet pile lock, first slowly and then quickly. The top of the Larsen steel sheet pile is lower than the elevation of the retained road surface. When clamping the pile, there should be no gap between the clamping device and the head of the pile. The vibrating pile hammer can only be started when the working pressure of the hydraulic system is stable. Before sinking the pile, the front end of the pile should be positioned, and the verticality of the guide rail and the pile should be adjusted as required. When the vibrating pile hammer is operating, the friction parts of the vibration reduction device are well lubricated. When the amplitude of the shock absorber beam exceeds the regulations, the machine should be stopped to find out the reason. When sinking the pile, apply butter inside the steel sheet pile lock. Loosen the pile hanging wire rope according to the pile sinking speed. The pile sinking speed and motor current shall not exceed the use regulations. When the pile sinking speed is too slow, the counterweight can be added to the vibrating pile hammer as required. When the current rises sharply, the machine should be stopped for inspection.

[0057] Step 4.4) Internal support installation. After the Larsen steel sheet piles 4 are arranged in a row, the corbels 5 are slotted and welded in time, and the top purlin is installed. The corbels are made of angle steel or I-beam, and the purlin 6 is obviously deformed after installation. The internal support is adopted, which has the characteristics of tooling, standardization, and turnover. Lift the inner steel support 7 and place it on the purlin, push the support rod to the purlin in the reserved hole of the casing, and then insert the discus into the reserved hole of the casing one by one. When the gap is not enough to insert the discus, knock in the conical wedges symmetrically at both ends.

[0058] Step 4.5) Excavation. Manual trenching is used within one meter before and after the underground pipeline to find out the location of the pipeline. The rest of the earthwork is excavated mechanically. To facilitate mechanical excavation, the top of the Larsen steel sheet pile is lower than the road surface elevation, and the excavator works on a special work frame. Before trenching, according to the existing pipeline marked in the "Underground Pipeline Protection Plan", manual trenching is used to find out and expose the pipeline location to prevent accidental damage to the machinery. When trenching, according to the suspension protection or relocation plan jointly formulated with the pipeline property unit, dismantling, relocation or suspension protection measures are taken to ensure the normal operation of the existing pipeline and avoid damage. When mechanical trenching, ensure that the soil at the bottom of the trench is not disturbed, and leave 20cm above the designed trench bottom elevation without excavation for manual excavation. The excavator uses a special working platform to excavate soil at the top of the trench. Strictly control the trench bottom elevation to prevent over-excavation. Excavate in sections according to a reasonable excavation sequence, route and excavation depth. When digging trenches mechanically, the contents include the trench section, the location of the earth pile, the existing underground structures and the construction requirements; it is directed by a dedicated person and equipped with a certain number of surveyors to conduct measurements at any time to prevent over-digging or under-digging. When the trench is deep, it should be excavated in layers, and the layer thickness is determined by the mechanical properties. The excavated earth should be loaded and transported out in time. Manual bottom cleaning should be carried out according to the design drawings and the measured center line and side lines. The bottom should be cleaned and leveled strictly according to the elevation line, and the original soil should not be damaged. Ensure that the size and elevation of the foundation trench meet the design requirements, and mechanical excavation should be combined with manual bottom cleaning. When excavating earthwork, a sump should be excavated at an appropriate location to centrally pump out a small amount of seepage water in the foundation pit.

[0059] Step 5) Foundation bearing capacity test:

[0060] Before the start of manual bottom cleaning of each construction section, notify the supervisor to arrange the foundation bearing capacity test, manually clean the soil to the design elevation, and promptly use light penetration test to test the foundation bearing capacity. After the test results meet the design requirements, the foundation trench is inspected, and the foundation trench inspection record is filled in if qualified. When the foundation bearing capacity test results do not meet the design requirements, the survey unit shall put forward treatment opinions based on the test results and on-site conditions, and the responsible parties shall jointly confirm the method of foundation treatment. The foundation treatment is selected in the order of rolling, improved rolling with cement (gravel), and replacement of stone (sand and gravel). The foundation rolling treatment uses a small rolling machine to compact the cleaned soil surface. After reaching the number of compaction times, re-test, and re-test the trench after passing. The foundation mixed cement (gravel) improved rolling treatment uses agricultural tillage machinery to loosen the foundation soil of a certain depth, sprinkle a certain amount of cement or gravel, and then loosen and mix well, and finally use a small rolling machine to compact and roll. After reaching the number of compaction times, re-test, and re-test the trench after passing. The depth and materials of the replacement of foundation stone (sand and gravel) are proposed by the survey unit and confirmed by the five responsible parties. The excavator uses a special working platform to dig out the soil within the treatment depth at the top of the trench and fill the replacement materials in layers. After the replacement is completed, the foundation load is tested and the trench is re-inspected if it is qualified.

[0061] Step 6) Pipeline, well seat installation and backfilling:

[0062] Step 6.1) Prefabrication of pipeline wellbore: Prepare pipeline prefabrication plan and wellbore prefabrication plan according to construction drawings and construction organization arrangement. Guide the prefabrication sequence and progress of pipeline and wellbore components to avoid backlog of prefabricated components, occupation of prefabrication site, or progress affected by materials. Prefabricated pipelines comply with "Concrete and Reinforced Concrete Drainage Pipes" (GB / T 11836-2023). Prefabricated wellbore is divided into manhole cover, standard section, and non-standard section at the bottom of wellbore from top to bottom.

[0063] Step 6.2) Installation of pipe well seat: prefabricated pipes and well seats are inspected on site. Prefabricated components are inspected on site for product quality certification, and component numbers, concrete strength, cross-sectional dimensions, and appearance quality are checked according to the plan. Lay out the lines. Before installation, pop up the well seat and the center line of the pipe bottom on the cushion layer, and check the bottom elevation; pipe installation. First hoist the well chamber base. After the well seat is fixed, backfill the well seat periphery to the lower part of the pipe cushion layer. Pipeline installation is to hoist the pipes one by one from downstream to upstream, and add gaskets between the pipe joints and squeeze them tightly. Pipes and well seats are installed and positioned, and the gaps between pipes, pipes and well chambers, and between well chambers are filled with waterproof mortar three times, and the flow channel concrete is poured in time. Finally, the well chamber heightening unit is hoisted.

[0064] When installing the pipeline and well seat, wait for the concrete strength of the flow channel in the closed water test section to exceed 2.5MPa, insert the airbag into the pipeline outside the closed water test section and inflate it, and inject water, observe and record according to the specifications. After the test is qualified, start backfilling the pipe side. If the test fails, check the leakage point, repair it and test it again.

[0065] The height control line is marked on the locating bars at both ends of the pipeline foundation. When pouring concrete, the wire is used to level and smooth the concrete surface.

[0066] Step 6.3) Backfill:

[0067] The pipe cushion layer is generally made of gravel cushion layer or concrete cushion layer. After the foundation trench is inspected and qualified, the gravel cushion layer is constructed, and the gravel cushion layer is laid and rolled in the full trench according to the virtual thickness of the gravel cushion layer. During the rolling process, attention should be paid to controlling the slope of the cushion layer. The concrete cushion layer construction is to lay out the center line of the pipeline, measure the cushion layer width and drive in the positioning steel bars, pull the wire to control the cushion layer width, and support the formwork. Mark the elevation control line on the positioning bars at both ends of the pipeline foundation. When pouring concrete, pull the wire to level and smooth the concrete surface. Trench backfill: Old road concrete, cement stabilization layer, and recycled gravel materials are preferred for backfilling; starting from the periphery of the well seat, symmetrically backfill the pipe side in layers upwards, with the height difference on both sides not exceeding 300mm, and small machinery is used for compaction below 500mm from the top of the pipe.

[0068] A pipeline foundation treatment layer 9 is arranged at the bottom of the four Larsen steel sheet piles, and the pipeline foundation treatment layer 9 is used for prefabricated pipeline well seat installation. A pipeline backfill layer 10 is arranged between the four Larsen steel sheet piles outside the pipeline well seat. When installing the well seat: the prefabricated well seat non-standard section 15 is arranged at the bottom of the 4 Larsen steel sheet piles, the prefabricated well seat standard section 16 is arranged on the prefabricated well seat non-standard section 15, and the prefabricated well seat standard section 16 is arranged on the prefabricated well seat standard section 16. A prefabricated concrete well cover 17 is arranged on the prefabricated well seat non-standard section 15, the prefabricated well seat standard section 16 and the 4 Larsen steel sheet piles are sequentially provided with the well seat periphery backfill first layer 18, well seat periphery backfill second layer 19, well seat periphery backfill third layer 20 from bottom to top; and when backfilling, an auxiliary truss group 8 is placed on the construction area of ​​the construction enclosure 1 of the excavated road surface cut 2 at the outside of the excavated part 3 of the pavement structure, and the roller excavation machinery uses the auxiliary truss group 8 to dig out the soil within the processing depth at the top of the trench, and fill the replacement material in layers. The trench is backfilled to the top support position, the supporting purlin is removed, and the Larsen steel sheet piles are filled with sand as they are pulled out. The piles shall be pulled out in the reverse order of the pile sinking. When the buried part of the pile body is pulled out 1.0m to 1.5m, the pile pulling shall be stopped. After the steel wire rope for pile lifting is tied, the pile pulling shall be started again. When the pile tip is only 1.0m to 2.0m from the ground, the pile pulling shall be stopped by vibration and the pile shall be pulled out directly by crane. After the pile is pulled out, the clamping device shall not be loosened before the steel wire rope for pile lifting is tightened.

[0069] Step 7) Road surface restoration:

[0070] The road surface is restored layer by layer according to the original road surface structure, including the cushion layer, base layer and surface layer. The overlap joints of the new and old road surfaces extend outward by no less than 500mm each layer, and a flat interface is set. The interface binder is applied at the junction of the new and old layers. When the asphalt concrete of the road surface cools down naturally to a surface temperature below 50℃ and the concrete strength of the road surface meets the design requirements, the machinery and materials are cleared and the enclosure is removed to open the traffic.

[0071] Although the present invention is described herein with reference to a number of illustrative embodiments of the present invention, it will be appreciated that those skilled in the art may devise many other modifications and implementations that fall within the scope and spirit of the principles disclosed herein. More specifically, within the scope of the present disclosure, drawings, and claims, a variety of variations and modifications may be made to the components and / or layout of the subject combination layout. In addition to the variations and modifications made to the components and / or layout, other uses will also be apparent to those skilled in the art.

Claims

1. A green municipal drainage pipeline construction method, characterized by: The method comprises the following steps: Step 1) Construction preparation; Step 2) Fence installation: Install construction fences (1) to isolate the construction area from the traffic area; Step 3) removing the pavement structure layer: digging a pavement cut (2) in the construction area between the construction fences (1), and digging out a trapezoidal pavement structure excavation portion (3) between the pavement cut (2); Step 4) Support structure construction: a guide frame is installed in the excavated part (3) of the pavement structure, and then a Larsen steel sheet pile (4) is driven into the excavated part (3) of the pavement structure, and then earth excavation is carried out; Step 5) Testing the bearing capacity of the foundation: Conduct a light penetration test to test the bearing capacity of the foundation; Step 6) Pipeline, well seat installation and backfilling: The pipeline and the well seat are installed in the area between the Larsen steel sheet piles (4). After installation, backfilling is performed, and then the supporting purlins (6) are removed, and the Larsen steel sheet piles (4) are pulled out and filled with sand; Step 7) road surface restoration; after backfilling, the excavated part of the road surface structure (3) is provided with a pipeline backfill layer (10), a pipeline backfill upper layer (11), a road surface cushion layer (12), and a road surface base layer (13) in order from bottom to top; and traffic is opened after the asphalt concrete of the road surface has cooled to the required temperature.

2. A green municipal drainage pipeline construction method according to claim 1, characterized in that: In the step 1), the construction preparation includes construction technology preparation, construction site preparation, construction material preparation, and construction test preparation.

3. A green municipal drainage pipeline construction method according to claim 1, characterized in that: In the step 2), the construction fence (1) uses modular columns, baffles, and diagonal braces that are assembled and fixed using taper screws, and the columns and diagonal braces are fixed to the road surface using expansion bolts.

4. A green municipal drainage pipeline construction method according to claim 1, characterized in that: In the step 3), the excavated construction waste is loaded onto trucks for transportation, crushed and processed, and then sieved and classified to be used as backfill material around the pipeline.

5. A green municipal drainage pipeline construction method according to claim 1, characterized in that: In the step 4), after the Larsen steel sheet piles (4) are arranged in a row, the corbels (5) and the purlins (6) are welded on the Larsen steel sheet piles (4), and the steel supports (7) are arranged between the purlins (6).

6. A green municipal drainage pipeline construction method according to claim 1, characterized in that: In the step 6), when the pipeline is installed, a pipeline foundation treatment layer (9) is arranged at the bottom between the Larsen steel sheet piles (4), the pipeline foundation treatment layer (9) is used to install the prefabricated pipeline well seat, and a pipeline backfill layer (10) is arranged between the Larsen steel sheet piles (4) outside the pipeline well seat.

7. A green municipal drainage pipeline construction method according to claim 1, characterized in that: In the step 6), when the well seat is installed: a prefabricated well seat non-standard section (15) is arranged at the lower part between the Larsen steel sheet piles (4), a prefabricated well seat standard section (16) is arranged on the prefabricated well seat non-standard section (15), a prefabricated well seat standard section (16) is arranged on the prefabricated well seat standard section (16), and a prefabricated concrete well cover (17) is arranged on the prefabricated well seat non-standard section (15), the prefabricated well seat standard section (16) and the Larsen steel sheet piles (4) are provided with a first layer (18) of well seat periphery backfill, a second layer (19) of well seat periphery backfill, and a third layer (20) of well seat periphery backfill in sequence from bottom to top.

8. A green municipal drainage pipeline construction method according to claim 1, characterized in that: In the step 4), during earth excavation, an auxiliary truss group (8) is placed on the construction area between the construction fences (1) between the road surface cuts (2) outside the excavated part (3) of the road surface structure, and the roller excavation machine uses the auxiliary truss group (8) to excavate the soil within the processing depth at the top of the trench and fill the replacement material in layers.

9. A green municipal drainage pipeline construction method according to claim 1, characterized in that: In the step 6), a water-tightness test is carried out after the installation of the pipeline and the well seat, and backfilling is carried out after the water-tightness test. When the concrete strength of the flow channel in the water-tightness test section exceeds 2.5MPa, an air bag is inserted into the pipe outside the water-tightness test section to inflate it, and water is injected, observed, and recorded.

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