A novel construction method for pre-embedded conduits that eliminates the need for beam bottom formwork

Abstract

This invention discloses a novel construction method for pre-embedded conduits without penetrating the bottom formwork of beams, relating to the field of building construction engineering technology. The method includes the following steps: S1, preparation of the combined joint; S2, positioning of the conduit; S3, fixing the combined joint at the bottom of the beam; S4, connecting and fixing the conduit and joint; S5, pouring concrete and curing; S6, demolding. The combined joint is fabricated using steel nails, washers, foam blocks, and direct-fit connectors. The joint is nailed into the bottom formwork of the beam, and the PVC conduit is connected. Concrete is then poured. After the formwork is removed, the nails, foam blocks, and washers are removed along with the formwork, eliminating the need for further cleaning. This results in good concrete forming and avoids the costs associated with later repairs. Furthermore, the combined joint is simple to fabricate and easy to construct, significantly reducing the amount of conduit used. It also eliminates the need for drilling holes in the bottom formwork; by positioning the conduit on the bottom formwork, the location of the pre-embedded conduit is determined, avoiding quality defects such as grout leakage, resulting in excellent concrete forming.

Description

Technical Field

[0001] This invention relates to the field of building construction engineering technology, specifically a new construction method for pre-embedded conduits that eliminates the need for beam bottom formwork. Background Technology

[0002] The installation of pipelines through beams is an essential and important part of the installation project, which involves pre-embedding the pipelines during the main construction of the building structure. The quality of the pre-embedded pipelines directly affects the difficulty of the installation project.

[0003] Traditional construction methods involve drilling holes in the formwork to position conduits penetrating the bottom of beams, directly inserting the conduits into the holes. This mechanical drilling directly damages the formwork, shortening its lifespan. The drilling process generates a large amount of sawdust and wood chips on the formwork, especially at the bottom of the beam, which is difficult to clean and can easily lead to honeycomb and pitting defects in the concrete after it has set. Furthermore, if misaligned or abandoned conduit holes are not sealed promptly, grout leakage will occur, severely affecting the appearance quality of the concrete in those areas. Therefore, those skilled in the art have proposed a novel construction method for pre-embedded conduits that eliminates the need for penetrating the bottom formwork of beams, to solve the problems mentioned in the background section. Summary of the Invention

[0004] The purpose of this invention is to provide a novel construction method for pre-embedded conduits that eliminates the need for beam bottom formwork, in order to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A novel construction method for pre-embedded conduits that eliminates the need for beam bottom formwork includes the following steps: S1. Construction preparation of combination joints: The combination joints are manufactured in the processing plant using direct heads, foam blocks, gaskets and steel nails, and then transported to the construction site. S2. Conduit positioning: Complete the beam reinforcement binding, beam bottom formwork installation and reinforcement on site, and do not perform electric drilling, piercing, or enlarging operations on the beam bottom formwork throughout the entire process; S3. Beam Bottom Fixed Combination Joint: According to the construction drawings, accurately locate the pre-embedded position of the conduit on the surface of the beam bottom formwork and make permanent marks. Nail the combination joint into the positioning mark of the beam bottom formwork to complete the reliable fixation of the joint to the bottom formwork. S4. Connecting conduit and fixing joints: Use PVC conduit that matches the joint to connect with the combination joint. When encountering interference from steel bars, adjust the position of the steel bars to ensure that the PVC conduit remains vertical. Fix the upper part of the PVC conduit with the beam steel bar binding structure to prevent the conduit from floating, deviating, or being damaged during the pouring process. S5. Concrete pouring and curing: The concrete for the beam is poured and vibrated in layers, and cured according to the specifications after pouring. S6. Formwork Removal: After the concrete reaches the design strength, the bottom formwork of the beam is removed. The steel nails, foam blocks and gaskets in the combined joint fall off with the formwork, without the need for secondary manual cleaning.

[0006] As a further aspect of the present invention: the combined joint is made of a direct head, foam block, gasket, and steel nail, which are processed in a uniform size, standardized and quantitative manner in the processing plant. Before leaving the factory, it undergoes 100% quality inspection to ensure that the joint structure is firm, the specifications are uniform, and there is no looseness or damage.

[0007] As a further aspect of the present invention: the positioning of the beam bottom formwork is marked on the surface of the beam bottom formwork with conspicuous paint, and a comprehensive review is carried out after the positioning is completed, and the deviation of the pre-embedded hole position of the conduit is controlled within ±3mm.

[0008] As a further aspect of the present invention: before the combined joint is nailed into the bottom formwork of the beam, the surface of the bottom formwork of the beam must be cleaned of dust, wood chips and debris, and after nailing, the fixing firmness of the joint is checked point by point.

[0009] As a further aspect of the present invention: when the PVC conduit is connected to the combination joint, the verticality deviation of the conduit is no more than 1%, and steel bars are used to reinforce the conduit.

[0010] As a further aspect of the present invention: the concrete pouring is carried out in layers, and the layer thickness is no more than 40cm, and the pouring thickness is strictly controlled by a layer measuring rod.

[0011] As a further aspect of the present invention: the vibration is carried out by a quick insertion and slow withdrawal method, the vibration time of the first layer of concrete is controlled at 20s, and the vibration time of each subsequent layer is not less than 30s.

[0012] As a further aspect of the present invention: the concrete curing adopts full coverage of plastic film for moisture retention curing, and the water curing time is not less than 14 days.

[0013] Compared with the prior art, the beneficial effects of the present invention are: 1. This construction method adopts a new type of pre-embedded conduit construction technology that eliminates the need to penetrate the beam bottom formwork. It uses steel nails, washers, foam blocks, and direct connectors to process a combination joint. The joint is nailed into the beam bottom formwork, the PVC conduit is connected, and concrete is poured. After the formwork is removed, the nails, along with the foam blocks and washers, are taken away by the formwork, eliminating the need for further cleaning. The concrete forming effect is good, avoiding the cost of later repairs. At the same time, the combination joint is simple to make and easy to construct, which can greatly save on the use of conduit.

[0014] 2. The new type of pre-embedded conduit construction technology in this method eliminates the need to drill holes in the bottom formwork. By positioning the conduit on the bottom formwork, the location of the pre-embedded conduit is determined, avoiding quality defects such as grout leakage. The concrete forming effect is good. Matching PVC conduits are used to connect the joints and keep them vertical. The upper part of the conduit is fixed by binding the beam reinforcement before concrete pouring. This method has strong reference value for the construction of similar projects in the future. Attached Figure Description

[0015] Figure 1 This is a flowchart illustrating the operation of a novel construction method for pre-embedded conduits that eliminates the need for beam bottom formwork. Figure 2 This is a construction principle diagram for a new type of pre-embedded conduit that eliminates the need for beam bottom formwork. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] Please refer to the embodiments of the present invention for a novel construction method of pre-embedded conduit without penetrating beam bottom formwork, which includes the following steps: S1. Construction preparation of combination joints: The combination joints are manufactured in the processing plant using direct heads, foam blocks, gaskets and steel nails, and then transported to the construction site. S2. Conduit positioning: Complete the beam reinforcement binding, beam bottom formwork installation and reinforcement on site, and do not perform electric drilling, piercing, or enlarging operations on the beam bottom formwork throughout the entire process; S3. Beam Bottom Fixed Combination Joint: According to the construction drawings, accurately locate the pre-embedded position of the conduit on the surface of the beam bottom formwork and make permanent marks. Nail the combination joint into the positioning mark of the beam bottom formwork to complete the reliable fixation of the joint to the bottom formwork. S4. Connecting conduit and fixing joints: Use PVC conduit that matches the joint to connect with the combination joint. When encountering interference from steel bars, adjust the position of the steel bars to ensure that the PVC conduit remains vertical. Fix the upper part of the PVC conduit with the beam steel bar binding structure to prevent the conduit from floating, deviating, or being damaged during the pouring process. S5. Concrete pouring and curing: The concrete for the beam is poured and vibrated in layers, and cured according to the specifications after pouring. S6. Formwork Removal: After the concrete reaches the design strength, the bottom formwork of the beam is removed. The steel nails, foam blocks and gaskets in the combined joint fall off with the formwork, without the need for secondary manual cleaning.

[0018] Specifically, in this embodiment, the combined joint is made of a direct head, foam block, gasket, and steel nail, which are processed in a uniform size, standardized and quantitative manner at the processing plant. Before leaving the factory, it undergoes 100% quality inspection to ensure that the joint structure is firm, the specifications are uniform, and there is no looseness or damage.

[0019] Select high-quality direct connectors (such as the common Φ20 and Φ25 specifications) that match the PVC conduit specifications to ensure smooth conduit connection and good sealing. Use high-density closed-cell foam blocks, with cut dimensions precisely matching the bottom of the direct connectors and a thickness controlled at 15-20mm. This fills the gap between the direct connectors and the bottom formwork of the beam and allows them to fall off smoothly with the bottom formwork after concrete pouring, avoiding residue. Use galvanized steel plates with a thickness of 3-5mm, 20mm×20mm larger than the foam blocks, with a pre-drilled through hole in the center to match the steel nails. This helps to distribute the pressure of the steel nails and prevent the bottom formwork of the beam from being punctured or deformed. Use high-strength round steel nails, with the length determined according to the thickness of the bottom formwork of the beam (usually 30-50mm) to ensure that the joint is firmly fixed after being driven in, and that the top of the steel nail does not protrude from the surface of the gasket to avoid scratching the conduit or affecting concrete pouring.

[0020] During processing, specialized molds are used for positioning and assembly. First, the direct connector is bonded and fixed to the foam block (using an environmentally friendly, high-strength adhesive, ensuring a bubble-free and gap-free bonding surface). Then, the gasket is inserted into the steel nail, which is then passed through the center of the foam block and fixed to the bottom of the direct connector, ensuring that all components are concentric, tightly connected, and without any looseness. The processing plant implements batch production, and after each batch is completed, a 100% full inspection is conducted: checking the firmness of the connection of each component of the joint, ensuring that the direct connector does not loosen when gently pulled by hand and that the foam block does not fall off; checking the uniformity of specifications, measuring the overall dimensions of the joint and the inner diameter of the direct connector with calipers, with deviations controlled within ±1mm; checking the appearance quality, ensuring no damage, cracks, or rust (steel nails, gaskets), and that the foam block is undamaged and undeformed. All unqualified products are rejected and strictly prohibited from entering the construction site. In addition, each batch of products is accompanied by a quality inspection report, clearly stating the processing batch, quantity, and inspection results to ensure traceability.

[0021] In this specific embodiment, the positioning of the bottom formwork of the beam is marked on the surface of the bottom formwork with eye-catching paint. After the positioning is completed, a comprehensive review is carried out, and the deviation of the pre-embedded hole position of the conduit is controlled within ±3mm.

[0022] During positioning, eye-catching and wear-resistant paint such as red or yellow is used. Professional surveyors use a total station, level, and measuring tape to accurately lay out the lines. The center position of each joint is marked on the surface of the beam bottom formwork. The marking style is "cross line + circle", with the circle diameter not less than 50mm. The intersection of the cross lines is the center point of the joint nailing. This ensures that the marking is clear, eye-catching, and not easily contaminated or covered by subsequent construction.

[0023] After positioning is completed, a comprehensive review is conducted jointly by the construction team, technical briefing personnel, and quality inspectors, implementing a "dual review" system. The review includes: ensuring the hole positions match the construction drawings, checking if the number, spacing, and elevation of the holes meet design requirements; verifying the accuracy of the hole positions by measuring the distance between adjacent holes and the distance between the hole and the beam edge with a tape measure, and checking the verticality of the crosshairs with a spirit level, ensuring that the hole position deviation is controlled within ±3mm, and strictly prohibiting any deviation exceeding the standard; any deviations found during the review are immediately rectified, the lines are re-marked, and the review is repeated until the requirements are met. After the review is completed, a positioning review record is filled out, and relevant personnel sign to confirm, serving as a basis for construction quality traceability, ensuring that every pre-embedded hole position is accurate and laying the foundation for subsequent joint installation and conduit connection.

[0024] Specifically, in this embodiment, before the combined joint is nailed into the bottom formwork of the beam, the surface of the bottom formwork must be cleaned of dust, sawdust, and debris. After nailing, the joint should be checked point by point to ensure its firmness.

[0025] Use tools such as hair dryers and brushes to thoroughly remove dust, sawdust, cement slurry and other debris from the surface. If necessary, wipe it clean with a damp cloth to ensure that the surface of the beam bottom formwork is dry and clean. Avoid debris affecting the fixing effect of steel nails and prevent the joint from loosening or falling off. After cleaning, the operator holds the combination joint and aligns the foam block at the bottom of the joint with the cross point of the positioning mark to ensure that the joint is perpendicular to the surface of the beam bottom formwork and is not tilted.

[0026] When driving the nails in, gently tap the top of the nails with a wooden mallet, applying even and moderate force. Avoid using excessive force, which could bend the nails or damage the beam formwork, or using too little force, which could result in an insecure joint. The nails must be fully driven into the beam formwork until the shims are tightly fitted to the surface of the beam formwork, without gaps or looseness. After driving in, perform a point-by-point inspection: gently shake the straight head by hand to check if the joint is loose, and whether the foam block is tightly fitted to the beam formwork; check if the nails are vertical and free from bending or looseness; check if the shims are flat and free from misalignment.

[0027] Specifically, in this embodiment, when the PVC conduit is connected to the combination joint, the verticality deviation of the conduit is no more than 1%, and steel bars are used to reinforce the conduit.

[0028] Select PVC conduit that is perfectly matched to the specifications of the direct connector. The conduit must undergo quality inspection before arrival to ensure it is free of damage and cracks, has a smooth inner wall, and that the diameter deviation meets the specifications. Before connection, clean the dust and debris from the inner wall of the direct connector and the end of the PVC conduit. Cut the end of the PVC conduit into a 45° bevel to facilitate insertion into the direct connector, with an insertion depth of at least 20mm. After insertion, gently rotate the conduit to ensure a tight connection without gaps. If necessary, wrap sealing tape around the joint to enhance sealing and prevent concrete slurry from seeping into the conduit and clogging it.

[0029] During the connection process, the verticality of the PVC conduit must be strictly controlled. Real-time checks using tools such as a spirit level and plumb line are employed to ensure that the verticality deviation of the conduit does not exceed 1%, meaning a deviation of no more than 10mm per meter of conduit. Tilting or bending of the conduit is strictly prohibited to avoid affecting subsequent cable installation. When encountering interference from beam reinforcement, it is forbidden to force the conduit through. The reinforcement construction team must be notified immediately. Under the premise of not affecting the structural performance of the beam and complying with design specifications, the position of the reinforcement can be adjusted (e.g., adjusting the stirrup spacing, slightly moving the longitudinal reinforcement) to ensure the PVC conduit remains vertical and can be connected smoothly.

[0030] Specifically, in this embodiment, the concrete is poured in layers with a layer thickness of no more than 40cm. The layer thickness is strictly controlled by a layer measuring rod. Vibration is carried out by quick insertion and slow withdrawal. The vibration time of the first layer of concrete is controlled at 20s, and the vibration time of each subsequent layer is no less than 30s. The concrete is cured by full coverage with plastic film for moisture retention and water curing for no less than 14 days.

[0031] Concrete pouring adopts a layered pouring and layered vibration method, with the layer thickness strictly controlled within 40cm and not exceeding the specified thickness. This is to avoid pouring the upper layer of concrete after the lower layer has initially set, which would result in poor bonding between the two layers and cracks. To accurately control the layer thickness, a layer gauge rod is set every 1m on the inside of the beam side formwork. The gauge rod is made of non-deformable aluminum alloy and has clear markings (in cm). During the pouring process, the workers control the pouring height according to the gauge rod to ensure that the layer thickness meets the requirements.

[0032] Vibration is performed using an immersion vibrator, following the principle of "quick insertion and slow withdrawal." The vibrator should be inserted 5-10cm into the lower layer of concrete to ensure a tight bond between the upper and lower layers, without segregation or voids. Vibration time is strictly controlled: the first layer of concrete, being in direct contact with the beam formwork and joints, should be vibrated for 20 seconds to prevent loosening of joints and displacement of conduits due to excessive vibration. Subsequent layers should be vibrated for at least 30 seconds, until the concrete surface no longer settles, no more air bubbles appear, and the surface is flat and smooth. Under-vibration and over-vibration are strictly prohibited. Under-vibration will result in insufficient concrete density, while over-vibration will cause segregation, both of which will affect the beam quality and conduit safety.

[0033] After the concrete is poured, the surface should be smoothed and polished promptly to remove any laitance and ensure a flat beam surface. Curing should begin within 12 hours of pouring, using a full plastic film covering for moisture retention. The film should be tightly adhered to the beam surface and secured with weights around the edges to prevent air penetration and water loss, ensuring the concrete surface remains moist. Water curing should last at least 14 days, with the frequency adjusted according to the ambient temperature. In hot weather, water 3-4 times daily; in cold weather (below 5℃), implement insulation measures to prevent surface cracking. During curing, avoid collisions, shaking of the beam and embedded conduits, and do not place heavy objects on the beam to ensure normal concrete strength development until the design strength is reached.

[0034] The working principle of this invention is as follows: This invention provides a novel construction method for pre-embedded conduits that eliminates the need for beam-through formwork. This method utilizes a novel pre-embedded conduit construction technique that eliminates the need for beam-through formwork. Steel nails, washers, foam blocks, and direct connectors are processed into a combined joint. This joint is nailed into the beam-through formwork, the PVC conduit is connected, and concrete is poured. After the formwork is removed, the nails, along with the foam blocks and washers, are removed with the formwork, eliminating the need for further cleaning. The concrete forming effect is excellent, avoiding the costs associated with later repairs. Furthermore, the combined joint is simple to manufacture and easy to construct, significantly reducing the amount of conduit used. A cost comparison analysis of the novel pre-embedded conduit construction method eliminating beam-through formwork and the traditional beam-through pre-embedded construction method is shown in the table below.

[0035] Cost Analysis Comparison Table

[0036] Therefore, the construction using the new type of pre-embedded conduit to avoid the need for beam bottom formwork has significant economic benefits, saving approximately 35% in construction costs and time, for a total cost saving of 315,000 yuan.

[0037] The new construction method of pre-embedded conduit without drilling into the bottom formwork eliminates the need for perforation, avoiding problems such as construction waste, formwork damage, and shortened service life caused by perforation. This method significantly saves timber and protects limited forest resources. It also reduces waste and sawdust generation, lowers noise pollution, and has excellent environmental benefits. The combined joints are simple to manufacture, easy to construct, and have low material consumption, aligning with the modern concepts of "energy conservation, emission reduction, low carbon emissions, and environmental protection." This method has strong reference value for similar projects and is highly applicable.

[0038] Application Examples Guiyang Evergrande Children's World Phase I Plot 7 Main Structure and Supporting Facilities Construction Project The project is located in Huaxi University Town, Guiyang City (at the junction of Huaxi District and Gui'an New Area). Construction began on August 16, 2018, and was completed on October 6, 2020. The project cost was 372.88 million yuan, with a building area of ​​188,187.46 square meters and a land area of ​​39,000 square meters. The relative elevation ±0.000 is equivalent to an absolute elevation of 1169.750 meters. The total building area is 188,200 square meters, of which 138,400 square meters are above ground and approximately 49,800 square meters are underground. The project includes three basement levels, with one basement level containing some commercial space. Above ground, it mainly consists of 10 high-rise buildings: buildings 1-9 are all high-rise residential buildings with 28-32 floors; building 10 is a public service center with 6 floors. The foundation uses manually excavated bored piles, isolated footings, strip footings, and raft foundations. The main structure is a reinforced concrete shear wall structure system with a design service life of 50 years and a seismic fortification intensity of 6 degrees.

[0039] This project employed a novel pre-embedded conduit construction technique that eliminates the need for beam bottom formwork. A combination joint was fabricated using direct connectors, foam blocks, gaskets, and steel nails. This joint was then nailed into the beam bottom formwork using a self-made internal fixing method, connecting the PVC conduit before concrete pouring. After the formwork was removed, the nails, foam blocks, and gaskets were removed along with the formwork, eliminating the need for further cleaning. This method yielded excellent results, saving approximately 32% in both construction costs and time.

[0040] Guiyang Evergrande Cultural Tourism City Gui'an Plot 21# and 30# Main Structure and Supporting Construction Project The project is located on the south side of Jiaxiu South Road, Gui'an New District, Guizhou Province, near Huaxi University Town. Construction began on November 15, 2018, and is scheduled for completion on March 26, 2021. The building area is 161,208.37 square meters, with a construction cost of 320 million yuan. The 21# cluster consists of 10 residential buildings and 1 kindergarten, primarily for residential, commercial, and school functions. Buildings 1# to 10# have two underground parking levels. Buildings 1#, 9#, and 10# have commercial spaces on floors 1-4 (podium). Buildings 4# and 5# are seven-story townhouses, and the kindergarten is three stories above ground. The remaining buildings are high-rise residential buildings, ranging from 27 to 32 stories. The foundation types include pile foundations, isolated footings, and strip footings. The structural system is a reinforced concrete shear wall structure with a design service life of 50 years and a seismic fortification intensity of 6 degrees.

[0041] This project employed a novel pre-embedded conduit construction technique that eliminates the need for beam bottom formwork. By using a self-made internal fixing method, the joint was nailed into the beam bottom formwork, connecting the PVC conduit before concrete pouring. After the formwork was removed, the nails, along with foam blocks and gaskets, were removed with the formwork, eliminating the need for further cleaning. This simplified construction process, improved conduit pre-embedding efficiency, and increased the integrity rate of conduit pre-embedded joints, resulting in overall savings of approximately 33% in construction costs and time.

[0042] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0043] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A novel construction method for pre-embedded conduits that eliminates the need for beam bottom formwork, characterized in that, Includes the following steps: S1. Construction preparation of combined joints: Combined joints are fabricated in the processing plant using direct heads, foam blocks, gaskets and steel nails, and then transported to the construction site. S2. Conduit positioning: Complete the beam reinforcement binding and beam bottom formwork installation and reinforcement on site, without drilling, piercing and enlarging the beam bottom formwork throughout the process; S3. Beam Bottom Fixed Combination Joint: According to the construction drawings, accurately locate the pre-embedded position of the conduit on the surface of the beam bottom formwork and make permanent marks. Nail the combination joint into the positioning mark of the beam bottom formwork to complete the reliable fixing of the combination joint and the bottom formwork. S4. Connecting conduit and joint fixing: Use PVC conduit that matches the combination joint for connection. When encountering interference from steel bars, adjust the position of the steel bars to ensure that the PVC conduit remains vertical. Fix the upper part of the PVC conduit with the beam steel bar binding structure to prevent the PVC conduit from floating, deviating or being damaged during the pouring process. S5. Concrete pouring and curing: The concrete for the beam is poured and vibrated in layers, and cured according to the specifications after pouring. S6. Formwork Removal: After the concrete reaches the design strength, the bottom formwork of the beam is removed. The steel nails, foam blocks and gaskets in the combined joint fall off with the formwork, without the need for secondary manual cleaning.

2. The construction method for pre-embedded conduits without needing to pass through beam bottom formwork as described in claim 1, characterized in that, The combined joint structure is made of direct heads, foam blocks, gaskets and steel nails processed in the factory according to uniform size, standardization and quantitative processing. Before leaving the factory, it undergoes 100% quality inspection to ensure that the combined joint structure is firm, uniform in specifications, and free from looseness and damage.

3. The construction method for pre-embedded conduits without needing to pass through beam bottom formwork as described in claim 1, characterized in that, The positioning of the beam bottom formwork is marked on the surface of the beam bottom formwork with conspicuous paint. After the positioning is completed, a comprehensive review is carried out, and the deviation of the pre-embedded hole position of the conduit is controlled within ±3mm.

4. The construction method for pre-embedded conduits without needing to pass through beam bottom formwork as described in claim 1, characterized in that, Before the combined joint is nailed into the bottom formwork of the beam, the surface of the bottom formwork must be cleaned of dust, sawdust, and debris. After nailing, the joint should be checked point by point to ensure its firmness.

5. The construction method for pre-embedded conduits without needing to pass through beam bottom formwork as described in claim 1, characterized in that, When the PVC conduit is connected to the combination joint, the verticality deviation of the conduit shall not exceed 1%, and the conduit shall be reinforced with steel bars.

6. The construction method for pre-embedded conduits without needing to pass through beam bottom formwork as described in claim 1, characterized in that, The concrete pouring is carried out in layers, with each layer not exceeding 40cm in thickness, and the pouring thickness is strictly controlled using a layer measuring rod.

7. The construction method for pre-embedded conduits without needing to pass through beam bottom formwork, as described in claim 1, is characterized in that... The vibration is performed using a quick insertion and slow withdrawal method. The vibration time for the first layer of concrete is controlled at 20 seconds, and the vibration time for each subsequent layer is no less than 30 seconds.

8. The novel construction method for pre-embedded conduits without needing to pass through beam bottom formwork, as described in claim 1, is characterized in that... The concrete curing process involves full coverage with plastic film for moisture retention, and watering for at least 14 days.

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