Construction technology for replacing and filling construction waste in culvert foundation

Abstract

The invention relates to the technical field of foundation construction, and provides a construction process for replacing and filling construction waste in a culvert foundation, which comprises the following steps: obtaining the construction waste, sorting, classifying and pretreating the construction waste, removing impurities in the construction waste, and obtaining regenerated filler with preset grading; excavating and treating a foundation pit; and layered filling and compaction are conducted, specifically, the regenerated filler is filled into the foundation pit in a layered mode, and compaction equipment is adopted for compaction after each layer of regenerated filler is filled. By means of the arrangement, harmful impurities in construction waste can be removed, the strength, quality and uniformity of regenerated filler can be guaranteed, the uniformity of the filler can be guaranteed through layered filling, the compactness and stability of the filler can be effectively controlled, gaps in the filler can be reduced through layered compaction, the compactness and bearing capacity of each layer of filler are guaranteed, and the construction efficiency is improved. Therefore, the overall stability and bearing capacity of the foundation are ensured.

Description

Technical Field

[0001] The invention relates to the technical field of foundation construction, and in particular to a construction process for replacing building waste in a culvert foundation. Background Art

[0002] Construction waste, also known as construction waste, usually refers to the abandoned soil, abandoned materials, slag, sludge and other wastes generated during the construction, reconstruction or expansion of various buildings and structures. The traditional treatment methods of construction waste are mainly open-air stacking or underground landfill, which not only occupies a large amount of land resources, but also has a negative impact on the surrounding environment and is prone to cause hidden dangers such as surface subsidence or landslides. Therefore, how to efficiently and sustainably recycle construction waste is of great significance to environmental protection.

[0003] By using scientific treatment methods to transform construction waste into reusable resources, it can not only reduce environmental pollution, but also save natural resources. Therefore, the harmless treatment and resource utilization of construction waste has gradually become a research hotspot. At present, using construction waste to replace natural aggregates as foundation fillers is one of the frontiers of construction waste resource utilization.

[0004] However, due to the complex composition, uneven mechanical properties and lack of good gradation of construction waste, the bearing capacity and stability of the foundation cannot be guaranteed. Therefore, how to ensure the bearing capacity and stability of the foundation after replacement is still an important issue that needs to be solved urgently. Summary of the invention

[0005] The present invention provides a construction process for replacing the foundation of a culvert with construction waste, which is used to solve the problem in the prior art that the bearing capacity and stability of the foundation replaced with construction waste are difficult to ensure, and can improve the bearing capacity and stability of the foundation.

[0006] The present invention provides a construction process for replacing building waste in a culvert foundation, comprising the following steps: Obtaining construction waste and sorting, classifying and pre-processing the construction waste, removing impurities in the construction waste, and obtaining recycled fillers with a preset gradation; Foundation pit excavation and treatment; Fill and compact the recycled filler in layers into the foundation pit, and use compaction equipment to compact each layer of the recycled filler.

[0007] According to a construction process for replacing culvert foundation with construction waste provided by the present invention, the pretreatment step comprises: performing primary crushing and primary sorting on the construction waste, removing metal, organic or inorganic light impurities and humus in the construction waste, and obtaining raw materials.

[0008] According to a construction process for replacing construction waste in a culvert foundation provided by the present invention, the pretreatment step further comprises: Crushing and screening the raw materials again to obtain recycled aggregates of different gradations; The recycled aggregates with different gradations were simulated and compacted, and the recycled aggregates with a gradation with a mud content of less than 10% after compaction were obtained as recycled fillers.

[0009] According to a construction process for replacing construction waste in a culvert foundation provided by the present invention, the light impurity content in the raw materials is not more than 1%, the organic matter content is not more than 2%, the concrete particle content is not less than 40%, and the soluble salt content is not more than 0.5%.

[0010] According to a construction process for replacing construction waste in a culvert foundation provided by the present invention, the content of particles larger than 5 mm in the recycled filler is not less than 85%, and the unevenness coefficient is not less than 5.

[0011] According to a construction process for replacing construction waste in a culvert foundation provided by the present invention, the foundation pit excavation and treatment steps include: Mark out the foundation excavation line before excavation, and excavate according to the foundation excavation line during construction; The excavation slope of the foundation pit shall be sloped according to the construction process requirements and specifications, and an additional 50cm of formwork space and base drainage ditch position shall be dug on each side; The foundation pit is excavated by mechanical excavation. When it approaches the design elevation, manual bottom cleaning is used until it reaches the design elevation to ensure the flatness of the base and the excavation depth required by the design. Set up drainage measures, set up drainage ditches on the outside of the foundation, dig collection wells in the low-lying areas of the foundation pit, and install water pumps in the collection wells.

[0012] According to a construction process for replacing building waste in a culvert foundation provided by the present invention, in the layered filling and compacting steps, the thickness of each layer of recycled filler after compaction does not exceed 15 cm.

[0013] According to a construction process for replacing construction waste in a culvert foundation provided by the present invention, the layered filling and compacting steps include: Material transportation and spreading: transport the recycled filler to the replacement area, spread it in a plum blossom shape on the replacement surface, control the spacing of the spread according to the virtual thickness and the capacity of the transport bucket, and mark it; Spreading and picking up: use equipment to roughly level the recycled filler on the replacement surface, pick up debris in the recycled filler manually, and perform fine leveling operations to achieve the required elevation; Watering treatment: watering is carried out after paving is completed to achieve the optimal moisture content of the recycled filler; Compacting: Use vibratory rollers for rolling operations. At corners, use hydraulic tamping or small rollers for rolling. Then repeat the above steps until the design elevation is reached.

[0014] According to a construction process for replacing construction waste in a culvert foundation provided by the present invention, in the compaction step, two passes of static compaction are first performed during rolling, and then 4-6 passes of vibration rolling are performed. After the compaction degree and settlement difference meet the requirements, static compaction is performed again at last. During the rolling process, the principle of first slow and then fast, and from weak vibration to strong vibration is followed.

[0015] According to the construction process for replacing the foundation of a culvert with construction waste provided by the present invention, when the silt area is large relative to the replacement area and it is difficult to replace the entire area, stones can be thrown to squeeze the silt within a certain range, and a silt dam can be set up to carry out closed replacement; When the left and right settlements of the foundation are inconsistent, an integral cushion layer is set up to adjust the uneven settlement.

[0016] Beneficial effects: 1. Using recycled fillers from construction waste for foundation replacement not only reduces the exploitation of natural materials, but also reduces the negative impact of construction waste on the environment, which helps to achieve sustainable development and ecological protection. Compared with traditional natural stone, the raw materials and transportation costs of construction waste are lower. Recycling fillers from construction waste to replace natural aggregates and use them for foundation replacement can significantly reduce the cost of the project and improve the economic benefits of the project.

[0017] 2. The replacement of foundation with recycled fillers from construction waste is suitable for the replacement of foundations of various types of highway culverts. Whether it is a new construction project or a renovation and expansion project, efficient utilization of construction waste can be achieved through scientific and reasonable treatment and construction technology.

[0018] 3. After sorting, crushing and screening, the recycled fillers from construction waste can be directly used on the construction site. The construction process is simple and the construction efficiency is high. This method does not require high construction equipment and technology, is easy to operate, and is easy to promote and apply.

[0019] 4. It can remove harmful impurities in construction waste and ensure the strength, quality and uniformity of recycled fillers. Layered filling can not only ensure the uniformity of the filler, but also effectively control the density and stability of the filler. Layered compaction can reduce the voids in the filler and ensure the density and bearing capacity of each layer of filler, thereby ensuring the overall stability and bearing capacity of the foundation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a schematic flow chart of a construction process for replacing construction waste in a culvert foundation provided by an embodiment of the present invention.

[0022] Figure 2 It is a schematic diagram of the process of pretreatment of construction waste provided by an embodiment of the present invention.

[0023] Figure 3 It is a schematic diagram of the process of foundation pit excavation processing provided by an embodiment of the present invention.

[0024] Figure 4 It is a schematic diagram of the process of layered filling and compaction of recycled filler provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] In order to facilitate understanding of the construction process of replacing culvert foundation with construction waste provided by the present invention, its application background is first introduced. The rapid development of the construction industry is accompanied by a large amount of construction waste, and the unreasonable treatment of construction waste is likely to have an adverse impact on the environment. Therefore, how to efficiently and sustainably recycle construction waste is of great significance to protecting the environment.

[0027] The harmless treatment and resource utilization of construction waste has gradually become a research hotspot. At this stage, the use of construction waste to replace natural aggregates as foundation filler is one of the frontier areas of resource utilization of construction waste.

[0028] However, due to the complex composition, uneven mechanical properties and lack of good gradation of construction waste, the bearing capacity and stability of the foundation cannot be guaranteed. Therefore, how to ensure the bearing capacity and stability of the foundation after replacement is still one of the important issues that need to be solved urgently.

[0029] In view of the above problems, an embodiment of the present invention provides a construction process for replacing building waste in a culvert foundation, which can effectively improve the bearing capacity and stability of the replacement foundation.

[0030] Combine the following Figure 1-Figure 4 The construction process of replacing the foundation of a culvert with construction waste of the present invention is described. It should be pointed out that all raw materials involved in the embodiments of the present invention, unless otherwise specified, can be purchased from the market or obtained according to conventional methods familiar to those skilled in the art, and all equipment involved, unless otherwise specified, are common equipment in the field and can be operated by those skilled in the art according to common industry knowledge and technical means.

[0031] Reference Figure 1 A construction process for replacing building waste in a culvert foundation comprises the following steps: Step S1, obtaining construction waste and sorting, classifying and pre-processing the construction waste, removing impurities in the construction waste, and obtaining recycled fillers with a preset gradation.

[0032] Step S2: excavation and treatment of foundation pit.

[0033] Step S3, layered filling and compaction, filling the recycled filler into the foundation pit in layers, and using compaction equipment to compact each layer of the recycled filler.

[0034] By adopting the above-mentioned technical scheme, harmful impurities in construction waste can be removed and the strength, quality and uniformity of the recycled filler can be ensured. Layered filling can not only ensure the uniformity of the recycled filler, but also effectively control the density and stability of the recycled filler. Layered compaction can reduce the voids in the recycled filler, ensuring the density and bearing capacity of each layer of recycled filler, thereby ensuring the overall stability and bearing capacity of the foundation.

[0035] In one embodiment of the present invention, the construction waste in the above step S1 can be obtained from the market, or can be generated during the construction process.

[0036] After obtaining the construction waste, the construction waste is sorted to remove harmful substances, pollutants and seriously corrosive garbage in the construction waste, such as large pieces of domestic garbage, metal and wood, hazardous waste, electronic waste, etc. The sorted construction waste includes concrete blocks, slag, bricks and some small pieces of pollutants, such as wood chips, plastics, humus, foam, small pieces of metal and steel bars embedded in concrete blocks.

[0037] Then the sorted construction waste is classified and pre-processed, refer to Figure 2 , the classification and preprocessing steps mainly include: S10. Performing primary crushing and primary sorting on the construction waste, removing metals, organic or inorganic light impurities and humus in the construction waste, and obtaining raw materials.

[0038] Specifically, a jaw crusher can be used to crush the sorted construction waste, and then the crushed construction waste can be initially sorted through a screening process to sort out block materials (such as concrete blocks or bricks), slag (including mud and humus), steel bars and light debris (including organic or inorganic light impurities, such as wood chips, plastics, foam, grass, tree roots, etc.).

[0039] Specifically, the screening process may include vibrating screen screening, wind sorting, magnetic separation and water washing; wherein, vibrating screen screening can remove debris from construction waste, wind sorting can remove organic or inorganic light impurities from construction waste, magnetic separation can remove metal impurities from construction waste, and water washing can remove soluble impurities in construction waste, such as soluble salts.

[0040] The raw materials obtained after primary sorting should meet the following requirements: The content of light impurities is not more than 1%, the content of organic matter is not more than 2%, the content of concrete particles is not less than 40%, and the content of soluble salt is not more than 0.5%, thereby ensuring the overall density, strength and compaction effect of the recycled filler, and ensuring the strength and structural stability of the replacement foundation.

[0041] S11. Crushing and screening the raw materials again to obtain recycled aggregates of different gradations.

[0042] S12. Simulate compaction of recycled aggregates of different gradations to obtain recycled aggregates with a gradation in which the mud content after compaction is less than 10% as recycled fillers.

[0043] Specifically, in the embodiment of the present invention, the mud content refers to the content of particles with a particle size less than 0.075 mm.

[0044] A certain amount of mud content can improve the compactness of the recycled filler, thereby improving the bearing capacity of the replacement foundation. However, due to the high water absorption and water retention of small particles of soil, too much soil will reduce the overall drainage performance of the replacement material and increase the risk of foundation settlement. In addition, replacement materials with high mud content are prone to cracking after drying, which has an adverse effect on the long-term stability and durability of the foundation. By controlling the mud content, the stability of the foundation can be guaranteed while improving the compactness of the foundation.

[0045] Since the strength of recycled filler is relatively low, aggregates are squeezed against each other and will be crushed under a certain force, and the mud content will increase. By simulating the changes in grading after on-site compaction, the optimal grading range can be screened out to control the mud content of the replacement foundation after compaction and ensure the bearing capacity, stability and durability of the foundation.

[0046] For further illustration, the present invention will be described in detail by the following examples.

[0047] Specifically, through step S11, recycled aggregates with gradations of 0-31.5 mm, 0-19 mm, 4.75-19 mm, 9.5-19 mm and 4.75-31.5 mm are screened out, and crushed stone with a gradation of 9.5-19 mm is used as a comparison scheme. The screening test results are as follows.

[0048] The above gradations were subjected to compaction test and CBR test respectively, and the results are as follows.

[0049] From the above test results, it can be seen that the bearing ratio of recycled aggregate in the above-mentioned grading range is better than that of crushed stone. This is because the crushed stone has higher strength, and the particles are more complete after heavy compaction, and there is no embedding between the particles, so the state is loose and the CBR value is lower.

[0050] Through step S12, the recycled aggregate of the above grade is tested after simulated on-site compaction, and the screening test results are as follows.

[0051] From the above test results, it can be seen that the content of particles larger than 0.075 mm after compaction of recycled aggregates with gradations of 0-31.5 mm, 0-19 mm, 4.75-19 mm and 9.5-19 mm exceeds 10%, which does not meet the requirements. The content of particles larger than 0.075 mm after compaction of 4.75-31.5 mm is 8%, which meets the design requirements, and the CBR value can reach 86.4%, which is better than 64.0% of crushed stone. Therefore, recycled aggregate with a gradation of 4.75-31.5 mm is selected as recycled filler. Recycled fillers of 4.75-31.5 mm were used to carry out compaction tests and CBR tests at different concrete proportions. The results are as follows.

[0052] From the above test results, it can be seen that when the concrete particle content reaches 40%, the CBR value rises the most, and the CBR value is the largest when the content is 80%. In the case of 100% concrete particles, due to the lack of fine aggregate to fill the voids, it is not dense after compaction, and the CBR value is reduced, but it is still close to the CBR value of 40% concrete particles. The content of recycled filler in concrete should not be less than 40%.

[0053] Through the above step S1, the gradation ratio of the recycled filler and the content of each component in the recycled filler can be determined. After the gradation ratio of the recycled filler and the content of each component are determined, the foundation pit is excavated and processed.

[0054] In one embodiment of the present invention, referring to Figure 3 , the excavation and treatment steps of the foundation pit include: Step S20, pre-construction preparation: During the construction preparation stage, a series of measures need to be taken to ensure the quality, safety and efficiency of the construction process.

[0055] Step S20 mainly includes: Step S200: Setting physical isolation measures. Before construction, physical isolation measures should be set around the construction area to ensure the safety of the construction process.

[0056] Specifically, steel pipe green screen nets should be set up at construction sites along the line, and night reflective signs should be posted on the green screen nets to prevent safety accidents during night driving or construction.

[0057] Step S201, measurement and laying out, according to the requirements of the design drawings, accurately measure and lay out the axis and inner and outer edges of the box culvert and mark them with 40cm long bamboo stakes. The foundation excavation line should be marked with white lime to ensure the accuracy of the excavation range.

[0058] Step S202, depth marking and technical explanation, the excavation depth is clearly marked in the form of a technical explanation sheet and issued to the construction team and on-site construction workers to ensure the accurate execution of each construction step.

[0059] Step S203: Preparation of replacement filling materials.

[0060] Step S204, personnel and equipment configuration and on-site safety and construction management: Before construction, sufficient and qualified construction personnel and equipment must be deployed in accordance with construction requirements, including but not limited to key equipment such as excavators and rollers, as well as construction personnel with relevant qualifications and experience. Ensure that the site is equipped with necessary safety equipment and emergency facilities, and provide safety training for construction personnel to ensure that they are familiar with the construction process and safety operating specifications. Construction management personnel should strictly supervise and guide on-site in accordance with the technical briefing form and construction specifications to ensure the smooth progress of the construction process.

[0061] Step S21, excavation line marking: use lime to mark the foundation excavation line before excavation. During the construction process, excavation is carried out strictly according to the marked excavation line to ensure the accuracy of the excavation range.

[0062] Step S22, slope excavation: the excavation slope of the foundation pit is sloped according to the construction process requirements and specifications, and an additional 50 cm of formwork space and base drainage ditch position are excavated on each side.

[0063] Mechanical excavation is used for foundation pit replacement excavation to ensure efficiency and accuracy; when approaching the design elevation, manual bottom clearing is used until the design elevation is reached to ensure the flatness of the base and the excavation depth required by the design.

[0064] Step S23, set up drainage measures, set up drainage ditches on the outside of the foundation, and dig collection wells in the low-lying areas of the foundation pit to quickly drain the accumulated water when it rains. A water pump is installed in the collection well, and the accumulated water should be pumped away in time by the water pump to prevent the accumulated water from soaking the base, reducing the base bearing capacity, and affecting the quality of the project.

[0065] Step S24, excavation depth and bearing capacity detection, after the foundation pit is excavated to the design elevation, the construction unit shall be notified in time, and the design, supervision and other relevant units shall be organized to conduct acceptance. The acceptance content includes whether the foundation bearing capacity and excavation depth meet the design requirements. Only after the acceptance is qualified can the foundation backfill treatment be carried out. The construction layout and specific operations during the foundation pit replacement excavation process should ensure the accuracy and standardization of each step.

[0066] After the foundation pit is excavated, the replacement filling construction is carried out. The replacement filling is carried out by layered filling and compaction. Figure 4 , the layered filling and compaction steps include: Step 30, material transportation and spreading, transport the recycled filler to the replacement area, spread it in a plum blossom shape on the replacement surface, control the spacing of the materials according to the virtual paving thickness and the capacity of the transport bucket, and mark it on the replacement surface for subsequent paving and compaction operations.

[0067] Specifically, the so-called "plum blossom shape" means that when laying the material, the material is not laid continuously, but is placed in a dispersed manner at a certain interval to form a layout similar to a plum blossom pattern. This laying method helps to ensure the uniformity of the material after paving and reduce the situation of local over-density or over-sparseness.

[0068] Specifically, the thickness of each layer of recycled fill after compaction shall not exceed 15 cm.

[0069] Specifically, red paint can be used on the edge of the foundation pit to indicate the compaction thickness and number of each layer of filling for the purpose of supervision and inspection to ensure that the compaction of each layer meets the requirements during the construction process.

[0070] Step 31, spreading and picking up, uses equipment such as a loader or a bulldozer to roughly level the recycled filler on the replacement surface, and manually picks up debris in the recycled filler and performs fine leveling operations to achieve the required elevation.

[0071] Step 32: watering treatment. After paving is completed, watering treatment is carried out to achieve the optimal moisture content of the recycled filler; this helps to improve the plasticity and compaction effect of the filler and prepare for the subsequent roller rolling operation.

[0072] Step 33, compaction, use a vibratory roller for rolling operations, and use a hydraulic rammer or a small roller for rolling at the corners to ensure that the filler has no leakage, no dead corners, and is rolled evenly.

[0073] Specifically, a 26-ton vibratory roller is used for rolling operations. During the rolling process, two static compactions are performed first, followed by 4-6 vibration rollings. The principle of slow first and fast later, from weak vibration to strong vibration is followed to ensure that the compaction process is stable and effective. The rolling speed is controlled at 2km / h to ensure the quality and stability of the rolling. During the rolling process, the requirements of no leakage and no dead corners must be met, and the compaction must be uniform to ensure the density and stability of the foundation filler, until the compaction settlement difference meets the technical requirements. Finally, the static compaction of the roller is performed to further improve the density and stability of the filler.

[0074] During the filling and compaction process, strict quality inspection and control should be carried out, mainly including the inspection of key parameters such as thickness and compaction. Through field tests and laboratory tests, it is ensured that the quality of each layer of filling meets the design requirements to ensure the overall stability and bearing capacity of the foundation. Specifically, when monitoring the compaction of each layer, the thickness of each layer should be inspected every 100m 2 Test at least 3 locations.

[0075] Step 34: Repeat the above steps until the design elevation is reached.

[0076] After the packing layer is constructed, use a dynamic probe to test its bearing capacity to ensure that the quality and stability of the packing layer meet the technical requirements. Check the high level and flatness of the packing layer, and trim the parts that do not meet the requirements to ensure the quality and flatness of the entire packing layer.

[0077] In one embodiment of the present invention, when the silt area is large relative to the replacement area and it is difficult to replace the entire area, stones can be thrown within a certain range to squeeze out the silt, and a silt retaining dam can be set up to perform closed replacement; when the left and right settlements of the foundation are inconsistent, an integral cushion layer can be set up to adjust the uneven settlement.

[0078] Specifically, during the construction period, the soil and water conservation of the construction site should be kept in good condition, and sufficient drainage channels should be built in the drainage area and connected to permanent drainage facilities to effectively avoid soil erosion caused by accumulation of water.

[0079] In addition, effective preventive measures should be formulated to prevent the excavated materials from silting up in any river, waterway, irrigation or drainage system, thereby reducing the pollution of nearby water sources. The scope of vegetation destruction should be strictly controlled, and no other forms of human destruction are allowed except for the unavoidable occupation of land and felling.

[0080] Finally, during the construction period, water the construction site and construction access roads regularly to effectively reduce dust and reduce pollution to the surrounding environment. If there are residents within 200 meters of the construction site, arrange the construction time reasonably and arrange noisy operations during the day as much as possible. If construction must be carried out at night, the consent of the local government and environmental protection department must be obtained in advance.

[0081] It is to be understood that, without mutual contradiction, those skilled in the art may combine and combine the different embodiments or examples and the features of the different embodiments or examples described in this specification.

[0082] By using recycled fillers from construction waste for foundation replacement, not only the exploitation of natural materials is reduced, but also the negative impact of construction waste on the environment is reduced, which is helpful to achieve sustainable development and ecological protection. Compared with traditional natural stone, the raw materials and transportation costs of construction waste are lower. Replacing natural aggregates with recycled fillers from construction waste for foundation replacement can significantly reduce the cost of the project and improve the economic benefits of the project. In addition, foundation replacement with recycled fillers from construction waste is suitable for various types of highway culvert foundation replacement. Whether it is a new construction project or a renovation and expansion project, scientific and reasonable treatment and construction technology can be used to achieve efficient utilization of construction waste. At the same time, recycled fillers from construction waste can be directly applied to the construction site after sorting, crushing and screening. The construction process is simple and the construction efficiency is high. This method does not require high construction equipment and technology, is easy to operate, and is easy to promote and apply.

[0083] In addition, the construction process for replacing the foundation of a culvert with construction waste provided by the embodiment of the present invention can remove harmful impurities in the construction waste and ensure the strength, quality and uniformity of the recycled filler. The layered filling can not only ensure the uniformity of the filler, but also effectively control the density and stability of the filler. The layered compaction can reduce the voids in the filler, ensure the density and bearing capacity of each layer of filler, thereby ensuring the overall stability and bearing capacity of the foundation.

[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A construction process for replacing construction waste in culvert foundation, characterized in that: The following steps are involved: Obtaining construction waste and sorting, classifying and pre-processing the construction waste, removing impurities in the construction waste, and obtaining recycled fillers with a preset gradation; Foundation pit excavation and treatment; Fill and compact the recycled filler in layers into the foundation pit, and use compaction equipment to compact each layer of the recycled filler.

2. The construction process for replacing the foundation of a culvert with construction waste according to claim 1 is characterized in that: The pretreatment step includes: performing primary crushing and primary sorting on the construction waste, removing metals, organic or inorganic light impurities and humus in the construction waste, and obtaining raw materials.

3. The construction process for replacing the foundation of a culvert with construction waste according to claim 2 is characterized in that: The pre-processing step also includes: Crushing and screening the raw materials again to obtain recycled aggregates of different gradations; The recycled aggregates with different gradations were simulated and compacted, and the recycled aggregates with a gradation with a mud content of less than 10% after compaction were obtained as recycled fillers.

4. The construction process for replacing the foundation of a culvert with construction waste according to claim 2 is characterized in that: The raw materials contain light impurities at a content of no more than 1%, organic matter at a content of no more than 2%, concrete particles at a content of no less than 40%, and soluble salt at a content of no more than 0.5%.

5. The construction process for replacing the foundation of a culvert with construction waste according to claim 3 is characterized in that: The content of particles larger than 5 mm in the recycled filler is not less than 85%, and the non-uniformity coefficient is not less than 5.

6. The construction process for replacing the foundation of a culvert with construction waste according to any one of claims 1 to 5, characterized in that: The foundation pit excavation and treatment steps include: Mark out the foundation excavation line before excavation, and excavate according to the foundation excavation line during construction; The excavation slope of the foundation pit shall be sloped according to the construction process requirements and specifications, and an additional 50cm of formwork space and base drainage ditch position shall be dug on each side; The foundation pit is excavated by mechanical excavation. When it approaches the design elevation, manual bottom cleaning is used until it reaches the design elevation to ensure the flatness of the base and the excavation depth required by the design. Set up drainage measures, set up drainage ditches on the outside of the foundation, dig collection wells in the low-lying areas of the foundation pit, and install water pumps in the collection wells.

7. The construction process for replacing the foundation of a culvert with construction waste according to claim 1, characterized in that: In the layered filling and compacting steps, the thickness of each layer of recycled filler after compaction does not exceed 15 cm.

8. The construction process for replacing the foundation of a culvert with construction waste according to claim 1, characterized in that: The layered filling and compacting steps include: Material transportation and spreading: transport the recycled filler to the replacement area, spread it in a plum blossom shape on the replacement surface, control the spacing of the spread according to the virtual thickness and the capacity of the transport bucket, and mark it; Spreading and picking up: use equipment to roughly level the recycled filler on the replacement surface, pick up debris in the recycled filler manually, and perform fine leveling operations to achieve the required elevation; Watering treatment: watering is carried out after paving is completed to achieve the optimal moisture content of the recycled filler; Compacting: Use vibratory rollers for rolling operations. At corners, use hydraulic tamping or small rollers for rolling. Then repeat the above steps until the design elevation is reached.

9. The construction process for replacing the foundation of a culvert with construction waste according to claim 8, characterized in that: In the compaction step, static compaction is first performed twice, and then vibration compaction is performed 4-6 times. After the compaction degree and settlement difference meet the requirements, static compaction is performed again. The principle of slow first and fast later, and from weak vibration to strong vibration is followed during the compaction process.

10. The construction process for replacing the foundation of a culvert with construction waste according to claim 6, characterized in that: When the silt area is large relative to the replacement area and it is difficult to replace all the silt, stones can be thrown within a certain range to squeeze the silt, and silt-blocking dams can be set up to carry out closed replacement; When the left and right settlements of the foundation are inconsistent, an integral cushion layer is set up to adjust the uneven settlement.

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