Prestressed backfill unit assembly method

Abstract

The invention belongs to the technical field of buildings, and particularly relates to a prestressed backfill unit assembly type method which comprises the following steps: step 1, excavating a foundation pit on site; 2, screening the filled soil generated by excavation to form a raw material of the backfilled soil; 3, prefabricating unit modules of the prestressed backfill units on site; and fourthly, the prefabricated unit modules are spliced from the bottom of the foundation pit to the floor elevation, and concrete pouring is conducted after assembly is completed. According to the method provided by the invention, the modular prestressed soil units are spliced on site, the dividing seams are naturally formed among the units, meanwhile, the manufacturing cost of the backfill soil is relatively low, and the backfill soil and unit templates manufactured by using waste templates are also utilized as wastes, so that the current green and low-carbon environmental protection concept is met. And the manufacturing method of the unit module in the step 3 can well control the quality of backfill soil.

Description

Technical Field

[0001] The present invention belongs to the field of construction technology, and particularly relates to a pre-stressed backfill soil unit assembly method. Background Art

[0002] With the rapid development of the national economy, the construction of industrial factories (including industrial buildings on upper floors) is increasing, and the requirements for the bearing capacity and deformation of the floor are also getting higher and higher. In the prior art, the backfill soil under the floor is usually filled on-site and compacted layer by layer. For the floor structure itself, a reinforced concrete structure is generally adopted. The bearing capacity and deformation of the floor mainly depend on the quality of the backfill soil under the floor and the structural practice of the floor itself. This problem exists not only in industrial factories but also in municipal roads and other places where backfill soil is required.

[0003] Currently, in the prior art, the method of backfill soil under the floor: It is usually required to backfill and compact layer by layer, and quality requirements are put forward for the backfill soil. However, due to various factors such as unqualified quality of the backfill soil source, failure to compact layer by layer, and non-compliance with the compaction coefficient requirements, the backfill soil will be not dense, which becomes a main cause of floor cracking in the later stage.

[0004] For the construction of industrial factories, due to the large floor load of industrial factories, generally 2 - 10 tons per square meter, the floor structure itself usually adopts a reinforced concrete slab about 300mm thick due to load requirements, which has a greater impact on the cost. At the same time, the production and use of concrete will bring carbon emissions and are not environmentally friendly. In addition, large-area cast-in-place floors are prone to temperature shrinkage cracks. Summary of the Invention

[0005] The purpose of the present invention is to provide a pre-stressed backfill soil unit assembly method, which is used to solve the technical problems that in the prior art, it is easy to have non-dense backfill soil causing floor cracking, and for large-area industrial factory floors with large loads, it is difficult to apply the existing backfill soil technology, and it has to use thick reinforced concrete slabs.

[0006] The described pre-stressed backfill soil unit assembly method includes the following steps:

[0007] Step 1: Excavate the foundation pit on-site;

[0008] Step 2: Screen and process the fill soil generated by the excavation to form the raw material of the backfill soil;

[0009] Step 3: Prefabricate the unit modules of the pre-stressed backfill soil unit on-site;

[0010] Step 4: Assemble the prefabricated unit modules from the bottom of the foundation pit to the floor elevation, and after completion of the assembly, conduct concrete pouring.

[0011] Preferably, the Step 2 includes the following sub-steps:

[0012] Step 1: Prepare a steel hoop mold as a prestressing pressure device;

[0013] Step 2: Place the unit formwork close to the inner sides of the steel hoop formwork;

[0014] Step 3: Fill the space enclosed by the unit template with backfill soil;

[0015] Step 4: Apply prestress to the steel hoop form to squeeze and compact the backfill soil inside, and then lock the adjacent unit formwork through the tensioning and fixing device;

[0016] Step 5: Take out the prefabricated unit module.

[0017] Preferably, the steel hoop mold is formed by hooping with thick steel plates, has a square or rectangular shape, and can apply prestress, and a hanging ring is provided on the steel hoop mold.

[0018] Preferably, the steel hoop mold can be set on the assembly line. After the prefabrication of the unit modules is completed, the unit modules are taken out and the steel hoop mold is cleaned, and the steel hoop mold can be reused for subsequent prefabrication of the unit modules.

[0019] Preferably, the unit formwork is modified from discarded wooden formwork or steel formwork and corresponds one-to-one to each side of the prestressed pressure device. A second hanging ring is set on the top surface of the unit formwork, and the unit formwork is shorter than the side length of the corresponding side of the prestressed pressure device.

[0020] Preferably, in step 2, the excavated fill is screened, and raw fill, clay, and construction waste of good quality are selected through screening as raw materials for backfilling to form backfill, and the backfill, unit formwork, and steel hoop formwork are of the same height.

[0021] Preferably, in step 4, the tensioning and fixing device is a tensioned steel bar. After the prestress is applied, the steel bar is tightened and nailed into the ends of two adjacent unit formworks in a tensioned state, so that the two adjacent unit formworks are locked together. After the ends of all adjacent unit formworks are locked, the unit formworks are fixed.

[0022] Preferably, in step 5, the unit module inside the steel hoop mold is lifted out as a whole by removing the lifting ring 2 which serves as the steel hoop mold or by fixing the unit template, thereby separating the unit module from the prestressing pressure device.

[0023] Preferably, the side length of the steel hoop form is 2 to 3 meters, each end of the unit formwork is 200 mm away from the corresponding end of the corresponding side of the prestressed pressure device, and the thickness of the backfill soil is 300 to 500 mm.

[0024] Preferably, in step 4, the gaps between adjacent unit modules are filled with fine sand, and the thickness of the concrete pouring is 50 mm.

[0025] The advantages of the present invention are as follows: The method provided by the present invention utilizes the on-site assembly of modular prestressed soil units, and partition seams are naturally formed between the units. At the same time, the cost of backfill soil is relatively low, and the unit templates made from waste templates also belong to waste utilization, which conforms to the current environmental protection concept of green and low-carbon. The manufacturing method of the unit module in step three utilizes prestress to pre-compact the backfill soil and adopts a standardized manufacturing method, which can solve problems such as the quality and compaction degree of the backfill soil source and can well control the quality of the backfill soil. Specific Embodiments

[0026] Figure 1 It is the overall structure after the assembly of the unit module realized by a prestressed backfill soil unit assembly method of the present invention.

[0027] Figure 2 It is the top view of the unit module assembly structure in the present invention.

[0028] Figure 3 It is the schematic diagram of the processing flow of the unit module in a prestressed backfill soil unit assembly method of the present invention.

[0029] Figure 4 It is Figure 3 the schematic diagram of the structure of the unit module shown.

[0030] Figure 5 It is for processing Figure 3 the schematic diagram of the pipeline structure adopted by the unit module shown.

[0031] The reference numerals in the figure include: 1 steel hoop mold, 101 first lifting ring, 102 prestressed tensioning end, 2 unit template, 201 second lifting ring, 3 backfill soil, 4 tensioning and fixing device, 5 pipeline, 6 fine sand, 7 unit module. Specific Embodiments

[0033] The following combines the drawings and further elaborates on the specific embodiments of the present invention through the description of the embodiments to help those skilled in the art have a more complete, accurate and in-depth understanding of the inventive concept and technical solution of the present invention.

[0034] As Figures 1-5 shown, the present invention provides a prestressed backfill soil unit assembly method, including the following steps.

[0035] Step 1: Excavate the foundation pit on-site.

[0036] In this step, the upper miscellaneous fill is excavated on-site until the original soil is reached, forming a foundation pit.

[0037] Step 2: Screen the excavated fill to form the raw materials for the backfill soil 3.

[0038] In this step, screen the excavated fill, and select large-diameter stones and concrete blocks as the raw materials for production. The part of the fill containing domestic waste and pond sludge should be discarded. In some cases, the part containing domestic waste and pond sludge is treated and can be used as raw materials only after treatment.

[0039] Step 3: Prefabricate the unit module 7 of the prestressed backfill soil 3 on site.

[0040] During the prefabrication process of the unit module 7, it involves a prestress pressing device, a unit formwork 2, and the backfill soil 3 formed within the unit formwork 2. Among them, the prestress pressing device is a steel hoop form 1, generally using a square or rectangular module with a side length of 2 - 3 meters, which can apply prestress. A lifting ring 101 can be set on the top surface of each side of the steel hoop form 1 for convenient lifting, and a prestress tensioning end 102 is provided on the steel hoop form 1.

[0041] The unit formwork 2 can be made by refitting waste wooden formwork or steel formwork, and there are four, corresponding to each side of the prestress pressing device one by one. The unit formwork 2 should be shorter than the side length of the corresponding side of the prestress pressing device, and the unit formwork 2 is of the same height as the prestress pressing device. In the embodiment, there is a distance of 200 mm from each end of the unit formwork 2 to the corresponding end of the corresponding side of the prestress pressing device. A lifting ring 201 can be set on the top surface of the unit formwork 2 for convenient lifting.

[0042] The backfill soil 3 is formed by backfilling the raw materials after screening and treatment in Step 2. Specifically, the backfill soil 3 selects materials such as good-quality plain fill, cohesive soil, and construction waste through screening. The backfill soil 3 is filled into the unit module 7 with a thickness of 300 - 500 mm, and is of the same height as the prestress pressing device.

[0043] This step specifically includes the following sub-steps.

[0044] Step 1: Make the steel hoop form 1, which is surrounded by 3-mm-thick steel plates, and the height of the steel plates is 300 - 500 mm. The steel hoop form 1 can be set on the production line 5 and can be reused. That is, several steel hoop forms 1 are set on the production line 5. Each steel hoop form 1 sequentially executes the subsequent steps along the production line 5. After the prefabrication of the unit module 7 is completed, take out the unit module 7 and clean the steel hoop form 1, and it can be reused for the subsequent prefabrication of the unit module 7.

[0045] Step 2: Place the adjustable-length unit formwork 2 closely against the inner sides of each side of the steel hoop form 1, so that there is a distance of 200 mm from each end of the unit formwork 2 to the corresponding end of the corresponding side of the steel hoop form 1.

[0046] Step 3: Fill the space enclosed by the unit formwork 2 with backfill soil 3. The backfill soil 3 is selected from well-quality plain fill soil, cohesive soil, construction waste and other materials through screening. The backfill soil 3 is filled as densely as possible.

[0047] Step 4: Apply prestress to the steel hoop formwork 1 to compact the internal backfill soil 3, and then lock the adjacent unit formworks 2 through the tensioning and fixing device 4.

[0048] In this step, prestress is applied to the steel plates on each side of the steel hoop formwork 1 (tensioned through the prestress tensioning end 102) to compact the internal backfill soil 3. The tensioning and fixing device 4 is a tensioned steel bar. After the prestress is applied, the steel bar is tightened and nailed into the ends of two adjacent unit formworks 2 in a tensioned state, so that the two adjacent unit formworks 2 are locked together. The length of the steel bar is 6 mm. After all the ends of the adjacent unit formworks 2 are locked, the fixation of the unit formwork 2 is completed.

[0049] Step 5: Take out the prefabricated unit module 7.

[0050] If the prestress pressing device is not required to be reused, the steel hoop formwork 1 used as the prestress pressing device can be removed and the unit module 7 can be taken out. If the prestress pressing device needs to be reused, after the prestress pressing is stopped, the inner unit module 7 is lifted out as a whole through the second lifting ring 201 of the fixed unit formwork 2. In this way, the unit module 7 containing the backfill soil 3 and the unit formwork 2 is separated from the prestress pressing device. The steel hoop formwork 1 arranged on the assembly line 5 can still perform repetitive operations after the unit module 7 is lifted out.

[0051] Step 4: Assemble the prefabricated unit module 7 from the bottom of the foundation pit to the ground floor elevation, and perform concrete pouring after completion of the assembly.

[0052] The unit modules 7 are assembled from the bottom of the foundation pit to form an integral structure, and the gaps between adjacent unit modules 7 are filled with fine sand 6. When the unit modules 7 are assembled to the ground floor elevation, the prefabricated assembly construction is completed. Then, 50-mm-thick building concrete can be poured, and then the building waterproofing and building floor practices (such as terrazzo, epoxy floor, etc.) are continued.

[0053] This method uses modular prestressed soil units for on-site assembly. Partition joints are naturally formed between the units. At the same time, the cost of the backfill soil 3 is relatively low, and both the unit formwork 2 made of waste templates belong to waste utilization, which conforms to the current green and low-carbon environmental protection concept. The manufacturing method of the unit module 7 in step 3 uses prestress to pre-compact the backfill soil 3 and adopts a standardized manufacturing method, which can solve problems such as the quality and compactness of the backfill soil 3 source and can well control the quality of the backfill soil 3.

[0054] The present invention has been described exemplarily above with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited by the above-mentioned manner. As long as various non-substantive improvements are made by adopting the inventive concept and technical solution of the present invention, or the inventive concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A prestressed backfill soil unit assembly method, characterized in that: The following steps are involved: Step 1: Excavate the foundation pit on site; Step 2: Screening and processing the fill soil produced by excavation to form raw materials for backfill soil; Step 3, prefabricating unit modules of prestressed backfill soil units on site; Step 4: Assemble the prefabricated unit modules from the bottom of the foundation pit to the floor elevation, and pour concrete after assembly is completed.

2. A prestressed backfill soil unit assembly method according to claim 1, characterized in that: The step 2 includes the following sub-steps: Step 1: Prepare a steel hoop mold as a prestressing pressure device; Step 2: Place the unit formwork close to the inner sides of the steel hoop formwork; Step 3: Fill the space enclosed by the unit template with backfill soil; Step 4: Apply prestress to the steel hoop form to squeeze and compact the backfill soil inside, and then lock the adjacent unit formwork through the tensioning and fixing device; Step 5: Take out the prefabricated unit module.

3. A prestressed backfill soil unit assembly method according to claim 2, characterized in that: The steel hoop mold is made of thick steel plates, has a square or rectangular shape, and can be prestressed. A lifting ring is set on the steel hoop mold.

4. A prestressed backfill soil unit assembly method according to claim 3, characterized in that: The steel hoop mold can be set on the assembly line. After the prefabrication of the unit module is completed, the unit module is taken out and the steel hoop mold is cleaned, and the steel hoop mold can be reused for the subsequent prefabrication of the unit module.

5. A prestressed backfill soil unit assembly method according to claim 2, characterized in that: The unit formwork is modified from discarded wooden formwork or steel formwork, and corresponds to each side of the prestressed pressure device one by one. A lifting ring is set on the top surface of the unit formwork, and the unit formwork is shorter than the side length of the corresponding side of the prestressed pressure device.

6. A prestressed backfill soil unit assembly method according to claim 2, characterized in that: In the step 2, the excavated backfill is screened, and the plain backfill, clay soil and construction waste with better quality are selected as raw materials for backfilling to form backfill soil. The backfill soil, unit formwork and steel hoop formwork are of the same height.

7. A prestressed backfill soil unit assembly method according to claim 2, characterized in that: In step 4, the tensioning and fixing device is a tensioned steel bar. After the prestress is applied, the steel bar is tightened and nailed into the ends of two adjacent unit templates in a tensioned state, so that the two adjacent unit templates are locked together. After the ends of all adjacent unit templates are locked, the unit templates are fixed.

8. A prestressed backfill soil unit assembly method according to claim 2, characterized in that: In the step 5, the unit module inside the steel hoop mold is hoisted out as a whole by removing the lifting ring 2 which serves as the steel hoop mold or by fixing the unit template, so that the unit module is separated from the prestressing pressure device.

9. A prestressed backfill soil unit assembly method according to claim 2, characterized in that: The side length of the steel hoop formwork is 2 to 3 meters, each end of the unit formwork is 200 mm away from the corresponding end of the corresponding side of the prestressed pressure device, and the thickness of the backfill soil is 300 to 500 mm.

10. The method for assembling a prestressed backfill soil unit according to claim 1, characterized in that: In the step 4, the gaps between adjacent unit modules are filled with fine sand, and the thickness of the concrete pouring is 50 mm.

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