A blade foot embedded type trench steel formwork pouring construction method

Abstract

A method for constructing trench steel formwork with embedded cutting edge, relating to the field of trench construction technology, includes establishing an installation control relationship between cross piles and the formwork forming surface based on the trench forming dimensions; forming a concrete cushion layer at the bottom of the trench and setting cross piles; generating formwork installation correction amounts after checking the cross pile status; sliding the first steel formwork along the cross piles so that its bottom cutting edge is inserted into the bottom of the trench, and correcting the top opening, the middle socket, and the bottom cutting edge; then installing the second steel formwork and tie rods to form a closed formwork system; pouring concrete in layers and adjusting according to the formwork displacement, solving the problem of difficult positioning and support of existing trench steel formwork in narrow spaces.

Description

Technical Field

[0001] This invention relates to the field of trench construction technology, specifically to a method for casting trench steel formwork with embedded blade feet. Background Technology

[0002] Trench construction is commonly used for the molding of concrete structures such as municipal pipelines, drainage ditches, and cable trenches. In existing trench concrete structure construction, the trench pit is typically excavated and the bottom treated first. Then, a concrete foundation layer is poured at the bottom of the trench. Steel or wooden formwork is then installed sequentially along both sides of the trench, secured with connectors, temporary supports, or tie rods. After the formwork position and internal dimensions are adjusted, concrete is poured. For long trenches, the formwork generally needs to be segmented and spliced, with transverse formwork at the ends to form a closed pouring space.

[0003] However, the distance between the trench sides and the formwork is usually small, limiting the working space for construction workers during formwork installation. Current methods often rely on manual labor to repeatedly straighten and adjust the formwork within the narrow trench and install supports. This lack of a stable guiding benchmark during formwork positioning easily leads to swaying, misalignment, or bottom slippage. Especially when assembling multiple formwork sections consecutively, installation deviations in the preceding sections can affect the splicing and end closure of subsequent sections, requiring multiple corrections during formwork erection and impacting trench formwork efficiency. Therefore, a construction method that can adapt to the narrow working space of trenches and facilitate rapid positioning and erection of steel formwork is urgently needed. Summary of the Invention

[0004] This invention provides a method for constructing trench steel formwork with a blade-embedded design. By pre-setting cross-shaped piles as guide references in the concrete cushion layer, the steel formwork is slidably installed along the cross-shaped piles. The bottom blade is embedded into the bottom of the trench to form a limit. Combined with formwork posture correction and tension constraint, this method solves the problem of difficulty in positioning and supporting existing trench steel formwork in narrow spaces.

[0005] A method for constructing a trench with embedded steel formwork includes the following steps:

[0006] S1. Based on the design and forming edge line of the foundation pit trench, the size of the steel formwork components and the insertion depth of the cutting edge, establish the installation control relationship between the cross pile and the forming surface of the formwork.

[0007] S2, a concrete cushion layer is formed at the bottom of the trench, and cross piles are set according to the installation control relationship;

[0008] S3, detect the guiding status of the cross pile and generate template installation correction amount based on the guiding status;

[0009] S4, make the first steel formwork slide down along the cross pile to the installation position, and insert the bottom cutting edge of the first steel formwork into the bottom of the trench;

[0010] S5, posture correction is performed based on the top position, middle socket position and bottom cutting edge position of the first steel formwork;

[0011] S6, Install the second steel formwork and tie rods to form a closed formwork system;

[0012] S7, pour concrete, and adjust according to the displacement of the top of the first steel formwork, the gap at the middle socket, the embedded state of the cutting edge, or the pre-tightening state of the tie rod.

[0013] Furthermore, the installation control relationship includes the correspondence between the design forming edge line of the concrete structure, the inner forming surface of the first steel formwork, the position of the middle bearing slot of the first steel formwork, and the center line of the cross pile. The installation control relationship is obtained by progressively deducing from the design forming edge line to the center line of the cross pile.

[0014] Furthermore, positioning holes for inserting cross piles are formed in the concrete cushion layer, or cross piles are inserted before the concrete cushion layer initially sets, so that the lower end of the cross pile is fixed to the concrete cushion layer, and the guide edge of the cross pile faces the middle support slot of the first steel formwork.

[0015] Furthermore, the guiding state includes the axial deviation of the cross pile, the orientation deviation of the guiding edge, and the spacing deviation between adjacent cross piles. The template installation correction amount is generated based on the deviation of the guiding state relative to the installation control relationship.

[0016] Furthermore, the template installation correction includes the lateral correction of the first steel template, the correction of the lowering height, the correction of the cutting edge pressing depth, and the correction of the tie rod preload.

[0017] Furthermore, as the first steel formwork slides down along the cross pile, the middle bearing slot of the first steel formwork forms a sliding connection with the guide edge of the cross pile. The sliding connection restricts the lateral swing of the first steel formwork, and the cutting edge is inserted into the bottom of the trench to restrict the bottom slippage of the first steel formwork.

[0018] Furthermore, the attitude correction includes determining the upper offset state of the first steel template based on the top position, determining the sliding fit state between the first steel template and the cross pile based on the middle guide position, determining the cutting edge embedding state based on the bottom embedding position, and selecting the corresponding correction action based on the upper offset state, sliding fit state, and cutting edge embedding state.

[0019] Furthermore, after the closed template system is formed, the end verticality, end joints, inner cavity width and diagonal dimensions of the second steel template are checked, and the inner cavity width between the two first steel templates is verified by the effective length of the tie rod.

[0020] Furthermore, during concrete pouring, after each layer is poured, the displacement of the top of the first steel formwork, the gap at the middle socket, the embedment status of the cutting edge, and the pre-tightening status of the tie rods are checked. When the top displacement exceeds the allowable displacement, the tie rods are adjusted. When the gap at the middle socket increases, the sliding connection between the first steel formwork and the cross pile is adjusted. When the bottom of the cutting edge shows a tendency to move outward, the pouring is suspended and the outside of the cutting edge is compacted or wedged.

[0021] Furthermore, during demolding, the first steel formwork is slid vertically in the opposite direction to the cross pile to release the sliding connection between the first steel formwork and the cross pile, and the second steel formwork and cross pile are removed after the cutting edge is removed from the bottom of the trench.

[0022] The beneficial effects of the above-described technical solutions provided in the embodiments of the present invention include at least the following:

[0023] This invention provides a stable guiding benchmark by forming a concrete cushion layer and installing cross-shaped piles at the bottom of the trench. The first steel formwork can slide down along the cross-shaped piles to the installation position, reducing the need for manual straightening and repeated support between the trench sidewalls and the formwork. A cutting edge is provided at the bottom of the first steel formwork. Once inserted into the bottom of the trench, the cutting edge limits the bottom of the formwork, reducing the possibility of bottom slippage during installation and pouring. By detecting and correcting the top opening, middle socket, and bottom cutting edge of the first steel formwork, corresponding adjustment methods can be selected based on the offset position, making formwork posture adjustment more reliable. After the second steel formwork and tie rods form a closed formwork system, the width of the formwork cavity and the displacement during the pouring process can be constrained, which helps maintain the forming dimensions of the trench concrete structure and improves the continuity of steel formwork support and pouring construction in narrow trenches.

[0024] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings.

[0025] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0026] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0027] Figure 1 This is a cross-sectional view of construction in a foundation pit trench as disclosed in an embodiment of the present invention;

[0028] Figure 2This is a three-dimensional structural diagram of the steel formwork assembly disclosed in an embodiment of the present invention;

[0029] Figure 3 This is a schematic diagram of the cross-shaped pile structure disclosed in an embodiment of the present invention;

[0030] Figure 4 This is a partial structural schematic diagram of the cross-shaped pile and steel formwork assembly disclosed in an embodiment of the present invention;

[0031] Figure 5 This is a flowchart of the method disclosed in an embodiment of the present invention.

[0032] Figure label:

[0033] 1. Excavation pit trench; 2. Concrete cushion layer; 3. Cross pile; 4. Steel formwork assembly; 41. First steel formwork; 411. Cutting foot; 42. Second steel formwork; 43. Tie rod. Detailed Implementation

[0034] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0035] This invention provides a method for constructing trench steel formwork with a blade-embedded design. This method is applicable to formwork construction during concrete structure pouring in foundation pit trenches, especially suitable for scenarios where the space on both sides of the trench is narrow, manual formwork erection is inconvenient, and traditional support and formwork construction need to be carried out in stages. The method involves pre-forming a concrete cushion layer 2 and cross piles 3 at the bottom of the trench, using the cross piles 3 as a vertical sliding guide reference for the first steel formwork 41. The blade 411 at the bottom of the first steel formwork 41 is then inserted into the bottom of the trench, allowing the steel formwork assembly 4 to be installed in the narrow trench through hooking, sliding, and embedding. Therefore, construction workers do not need to repeatedly erect supports and adjust the formwork between the trench sidewalls and the formwork, enabling formwork positioning, correction, closure, and pouring to be completed within a smaller working space.

[0036] The core technology of this invention lies in transforming the coordination relationship between the cross pile 3, the steel formwork assembly 4, and the cutting edge 411 into a positioning and correction relationship during the construction process.

[0037] Specifically, the cross pile 3 serves as the installation benchmark, sliding guide, and central limiting component for the first steel formwork 41; the middle part of the first steel formwork 41 slides and engages with the cross pile 3, and is secured at the bottom by the cutting edge 411; the tie rod 43 serves as a check component for the spacing between the two sides of the first steel formwork 41 and an anti-lateral pressure adjustment component during the pouring process. Through the synergistic effect of the above components, the formwork installation process is transformed from the traditional placement and support to a benchmark-guided sliding and securing process, thereby reducing the amount of manual adjustment during the formwork erection process.

[0038] like Figure 1 As shown, trench 1 is the trench space to be constructed. Concrete cushion 2 is located at the bottom of trench 1 and is used to provide a bottom construction benchmark for subsequent cross piles 3 and steel formwork assembly 4. Concrete cushion 2 is poured after trench excavation and bottom cleaning, and its upper surface serves as a reference surface for the exposed height of cross piles 3 and the installation elevation of steel formwork assembly 4.

[0039] In this embodiment, the concrete cushion layer 2 is also used to initially fix the lower end of the cross pile 3, so that the cross pile 3 remains stable during the subsequent installation of the steel formwork assembly 4.

[0040] like Figure 3 As shown, the cross-shaped pile 3 has a cross-shaped cross-section structure, with at least one edge or flange extending vertically. This edge or flange can slide and engage with the socket in the middle of the first steel formwork 41. The lower part of the cross-shaped pile 3 can be inserted into the concrete cushion 2 or the soil at the bottom of the trench, while the upper part is exposed above the concrete cushion 2, allowing the first steel formwork 41 to slide vertically. The advantage of the cross-shaped cross-section of the cross-shaped pile 3 is that its flanges in different directions can provide high bending stiffness, while also providing selectable guide edges for formwork installation in different directions. For straight trench sections, one guide edge of the cross-shaped pile 3 can face the installation side of the first steel formwork 41; for end or corner positions, the flanges in adjacent directions of the cross-shaped pile 3 can be used to assist in the positioning of the second steel formwork 42 or end formwork.

[0041] like Figure 2 As shown, the steel formwork assembly 4 includes multiple sets of first steel formwork 41, second steel formwork 42, and tie rods 43. The first steel formwork 41 forms the main formwork surfaces on both sides of the trench length direction. The second steel formwork 42 is installed at the end of a section of the steel formwork assembly 4 to cooperate with the first steel formwork 41 to form a closed formwork system. Both the first steel formwork 41 and the second steel formwork 42 can be equipped with cutting edges 411 at their bottoms. The cutting edges 411 can be inserted into the bottom of the trench 1. The cutting edges 411 can be a plate-like structure that gradually narrows downwards, or a wedge-shaped, triangular, or thinner-at-the-bottom insertion structure. Their function is to reduce the resistance when the steel formwork is inserted into the bottom of the trench and to form an anti-slip limiting mechanism after insertion.

[0042] like Figure 4 As shown, a partial sliding connection is formed between the first steel formwork 41 and the cross pile 3. A socket is provided in the middle of the first steel formwork 41, and the edge or flange of the cross pile 3 that contacts the first steel formwork 41 serves as a support. The socket can be fitted, hooked, or slid along the vertical direction of the cross pile 3. This sliding connection is used to limit the lateral swing of the first steel formwork 41, ensuring that the first steel formwork 41 maintains a predetermined posture during lowering. Unlike traditional formwork that requires manual straightening and support within the trench, in this embodiment, the first steel formwork 41 is guided and constrained by the cross pile 3 from the initial installation stage, thus reducing the probability of tilting or misalignment before the bottom of the formwork is firmly embedded.

[0043] The present solution will be described in detail below with reference to specific embodiments.

[0044] Example 1

[0045] like Figures 1-5 As shown in the figure, this embodiment details a method for casting a steel formwork for a groove with embedded blade, including the following steps.

[0046] Step S1: Establish the installation control relationship between the cross pile 3 and the steel formwork assembly 4.

[0047] After the excavation of the foundation pit trench 1 is completed and the bottom of the trench is cleaned, the positional relationship between the center line of the cross pile 3, the inner forming surface of the first steel formwork 41, and the edge line of the concrete cushion layer 2 is determined based on the design width of the foundation pit trench 1, the forming width of the concrete structure to be poured, the thickness of the first steel formwork 41, the thickness of the second steel formwork 42, the predetermined insertion depth of the cutting edge 411, and the installation height of the tie rod 43. This positional relationship is then used to determine the center position of the cross pile 3 and the orientation of the guide edge based on the position that the inner forming surface should reach after the formwork is installed.

[0048] Specifically, the design forming edge line of the concrete structure is first determined. Then, the position of the outer side of the first steel formwork 41 is determined based on its thickness. Next, the position of the guide edge of the cross pile 3 is determined based on the distance between the central bearing slot of the first steel formwork 41 and the inner forming surface of the formwork. Finally, the center line of the cross pile 3 is determined based on its cross-sectional dimensions. The above process involves progressively deducing the position of the installation reference from the final forming surface outwards.

[0049] Using this reverse calculation method, the cross pile 3 can directly become the guiding reference of the first steel formwork 41 after installation, avoiding the need to repeatedly correct the formwork position on site after installing the cross pile 3 first.

[0050] In this embodiment, the edge position of the concrete cushion layer 2 and the insertion area of ​​the cutting edge 411 can also be determined according to the predetermined insertion depth of the cutting edge 411. If the cutting edge 411 needs to be inserted into the soil outside the concrete cushion layer 2, the edge line of the concrete cushion layer 2 should avoid the insertion area of ​​the cutting edge 411; if the cutting edge 411 needs to be partially inserted into the reserved groove of the cushion layer, a corresponding shallow groove or softened insertion area can be formed when pouring the concrete cushion layer 2. The above settings can ensure that the cutting edge 411 has a stable insertion space after the first steel formwork 41 slides down to the predetermined elevation.

[0051] Step S2: Pour the concrete foundation 2 and install cross piles 3.

[0052] After the installation control relationship is determined, a concrete cushion layer 2 is poured at the bottom of the foundation pit trench 1. The thickness of the concrete cushion layer 2 can be determined according to the bearing capacity of the bottom of the trench, the fixing requirements of the cross piles 3, and the elevation requirements of the subsequent formwork installation. Before pouring the concrete cushion layer 2, the pile position control points of the cross piles 3 can be set at the bottom of the trench, and the relationship between each pile position control point and the trench axis can be checked by using a string line, laser line projector, or total station.

[0053] The cross piles 3 can be inserted before the initial setting of the concrete cushion layer 2, or they can be inserted after pre-drilling holes in the cushion layer. If inserted before initial setting, the lower end of the cross pile 3 is inserted into the concrete cushion layer 2, with the guide edge of the cross pile 3 that mates with the first steel formwork 41 facing the formwork installation side. After the concrete cushion layer 2 has set, the lower end of the cross pile 3 is fixed to the concrete cushion layer 2. If pre-drilling holes are used, positioning sleeves are pre-embedded or positioning holes are formed during the construction of the cushion layer. After the concrete cushion layer 2 reaches a certain strength, the cross pile 3 is inserted into the positioning holes and fixed by grouting, wedging, or mechanical locking.

[0054] In this step, the concrete cushion layer 2 is used not only to level the bottom of the trench but also to provide lower restraint for the cross piles 3. In traditional construction, supports and formwork are often installed separately, with the supports only providing local support. However, in this embodiment, the position of the cross piles 3 is determined during the cushion layer stage, allowing them to directly participate in the subsequent accuracy control of formwork installation. Thus, the benchmark for formwork construction shifts from the trench sidewalls or temporary manual supports to the stable benchmark system jointly formed by the concrete cushion layer 2 and the cross piles 3.

[0055] Step S3: Detect the guiding status of the cross pile 3 and generate the template installation correction amount.

[0056] Before installing the steel formwork assembly 4, the actual condition of the cross piles 3 is inspected. The inspection includes checking the verticality of the cross piles 3, the spacing between adjacent cross piles 3, the exposed height of the cross piles 3, the orientation of the guide edges, and the position of the guide edges relative to the formwork forming control line. Inspection tools can include a plumb line, straightedge, spirit level, laser rangefinder, total station, or a combination of commonly used on-site inspection tools.

[0057] After the inspection is completed, the template installation correction amount is determined based on the inspection results. This correction amount may include the lateral correction amount of the first steel template 41, the lowering height correction amount of the first steel template 41, the pressing depth correction amount of the cutting edge 411, and the pre-tightening correction amount of the tie rod 43.

[0058] Its computational logic includes:

[0059] The design forming control line is compared with the actual detected guide position of the cross pile 3, and the difference between the two is used as the direction and magnitude that need to be compensated when the first steel template 41 is installed laterally.

[0060] By comparing the designed top elevation of the first steel formwork 41 with the exposed height of the cross pile 3 and the measured elevation of the concrete cushion layer 2, the termination position that needs to be controlled when the first steel formwork 41 slides down is obtained.

[0061] By comparing the designed inner cavity width of the first steel template 41 on both sides with the measured guide reference distance, the adjustment amount that needs to be compensated when the tie rod 43 is initially pre-tightened is obtained.

[0062] It should be noted that the core of the above correction amount lies in first taking the concrete forming surface as the target, and then taking the measured guide position of cross pile 3 as the current benchmark. The adjustment direction during formwork installation is determined by comparing the target position with the current benchmark position. For the construction site, this correction amount can be recorded as operation instructions such as "adjust to the inside of the trench", "adjust to the outside of the trench", "increase the pressing depth" or "decrease the pressing depth", so as to facilitate the execution by on-site personnel.

[0063] Step S4: Install the first steel template 41 by first hooking it up, then sliding it down, and finally embedding it.

[0064] After the guide status of the cross pile 3 is inspected and approved or corrected, the installation of the first steel formwork 41 begins. During installation, the socket in the middle of the first steel formwork 41 is aligned with the guide edge of the cross pile 3, so that the first steel formwork 41 is initially connected to the cross pile 3 by hooking. At this time, the first steel formwork 41 has not completely fallen to the bottom of the trench, and the cutting edge 411 has not been fully inserted into the soil. The first steel formwork 41 is mainly guided and temporarily limited by the cross pile 3.

[0065] Subsequently, the first steel formwork 41 is lowered vertically along the cross pile 3. During the lowering process, the socket slides along the guide edge of the cross pile 3, and the cross pile 3 restricts the lateral sway of the first steel formwork 41, allowing the first steel formwork 41 to fall in the preset direction. When the bottom of the first steel formwork 41 approaches the bottom of the trench, the cutting edge 411 begins to contact the reserved area at the bottom of the trench soil or the edge of the cushion layer. The first steel formwork 41 is continued to be pressed down, so that the cutting edge 411 inserts into the bottom of the trench. After the cutting edge 411 is inserted, the bottom of the first steel formwork 41 is fixed by the soil or the edge of the cushion layer, and the middle is fixed by the sliding connection of the cross pile 3, thus forming a dual positioning state of middle guidance and bottom fixation.

[0066] The key to this installation method is that the first steel formwork 41 is not first aligned at the bottom before being connected to the support components. Instead, it is first hooked to the cross piles 3, then guided down through the cross piles 3, and finally secured by the cutting edge 411. For narrow foundation pits and trenches 1, this method reduces the time spent by personnel supporting and stabilizing the formwork on the outside. Even if the distance between the trench sidewall and the formwork is small, construction personnel can mainly operate the hooking and lowering of the first steel formwork 41 from above the trench or inside the formwork.

[0067] Step S5: Perform three-point posture detection and correction on the top, middle and bottom of the first steel template 41.

[0068] After the first steel formwork 41 is installed in place, its three-point posture is checked, including: the position of the top opening of the first steel formwork 41, the position of the middle socket of the first steel formwork 41, and the position of the bottom cutting edge 411 of the first steel formwork 41.

[0069] Specifically,

[0070] The top opening position is used to determine whether the upper end of the first steel template 41 deviates from the forming control line. When the detection finds that the top opening of the first steel template 41 is offset outward, it is corrected by temporary bracing, adjusting the pre-tightening direction of the tie rod 43, or slightly adjusting the upper position of the first steel template 41.

[0071] The position of the middle socket is used to determine whether the sliding connection between the first steel formwork 41 and the cross pile 3 is straight. When the detection finds that there is jamming, excessive gap or uneven sliding between the middle socket and the cross pile 3, the fit can be improved by cleaning the socket, adjusting the orientation of the guide edge of the cross pile 3, or setting a thin shim in the socket.

[0072] The position of the bottom cutting edge 411 is used to determine whether the lower end of the first steel template 41 has slipped or been insufficiently inserted. When the detection finds that the insertion depth of the cutting edge 411 is insufficient or the bottom position is offset, it can be corrected by local grooving, continuing to press down the first steel template 41, backfilling and compacting on the outside of the cutting edge 411, or setting temporary wedges.

[0073] The purpose of this three-point detection is to decompose the posture of the first steel formwork 41 into three control objects: the upper part, the middle part, and the bottom part. Traditional formwork correction usually only focuses on the top opening or verticality of the formwork, making it difficult to detect bottom slippage or middle guidance abnormalities in a timely manner. This embodiment can determine the source of formwork offset by simultaneously detecting the positions of the top opening, the middle socket, and the bottom cutting edge 411. When the top opening is offset but the middle and bottom parts are stable, the upper constraint is mainly adjusted; when the middle part is offset, the fit between the cross stake 3 and the socket is mainly adjusted; when the bottom is offset, the embedment state of the cutting edge 411 is mainly adjusted. Thus, formwork correction no longer relies on experience-based judgment, but selects the corresponding correction method according to the offset position.

[0074] Step S6: Install the second steel formwork 42 with the first steel formwork 41 as the longitudinal reference to form a closed formwork system.

[0075] After the first steel template 41 on both sides of a trench section is installed and passes the three-point posture test, the second steel template 42 is installed at both ends of the trench section. The width of the second steel template 42 can be smaller than that of the first steel template 41, and its bottom is also provided with a cutting edge 411. When installing the second steel template 42, the end of the second steel template 42 is connected to the adjacent first steel template 41, and the cutting edge 411 at the bottom of the second steel template 42 is inserted into the bottom of the trench. The second steel template 42 and the first steel template 41 can be connected by bolts, or by pins, clamps, or other detachable connectors.

[0076] After the second steel formwork 42 is installed, it forms a closed formwork system together with the first steel formwork 41 on both sides. After the closed formwork system is formed, the end verticality, end joints, inner cavity width, and diagonal dimensions are inspected. End verticality is used to determine whether the second steel formwork 42 is tilted; end joints are used to determine whether there is a risk of grout leakage between the first steel formwork 41 and the second steel formwork 42; inner cavity width is used to determine whether the width of the poured concrete meets the requirements; and diagonal dimensions are used to determine whether the closed formwork system has experienced planar torsion.

[0077] If the end joint is found to be too large during inspection, it can be corrected by adjusting the position of the second steel template 42 or increasing the preload of the connecting bolts; if the inner cavity width of the closed template system is found to be too large or too small during inspection, the second steel template 42 can be adjusted first, and then the end first steel template 41 can be finely adjusted; if the diagonal dimension deviation is found to be large during inspection, it indicates that the closed template system is twisted as a whole, which can be corrected by simultaneously adjusting the end positions of the first steel templates 41 on both sides and the connection angle of the second steel template 42.

[0078] Step S7: Install the tie rod 43 and use it as a spacing checker and anti-lateral pressure component.

[0079] Tie rods 43 are installed between the parallel first steel templates 41. The tie rods 43 can be spaced apart along the length of the trench or layered along the height. After the tie rods 43 pass through or connect the first steel templates 41 on both sides, they are pre-tightened by nuts or locking devices to maintain a predetermined distance between the first steel templates 41 on both sides.

[0080] In this embodiment, the tie rods 43 are used not only to resist the lateral pressure of the concrete during pouring, but also to quickly check the width of the inner cavity between the two first steel formworks 41. Specifically, the effective length of the tie rods 43 after locking is determined according to the designed width of the concrete structure and the position of the inner forming surface of the first steel formwork 41. During installation, each tie rod 43 is locked to its corresponding effective length, so that its two ends restrict the position of the two first steel formworks 41. If the effective lengths of multiple tie rods 43 at the same height are consistent, it indicates that the inner cavity width of the formwork at that height is consistent; if the adjustment amount of the tie rods 43 at different heights varies greatly, it indicates that the formwork may have a tendency to be larger at the top and smaller at the bottom, smaller at the top and larger at the bottom, or local bulging, requiring further adjustment.

[0081] The preload of the tie rod 43 can be determined using a comparative logic. First, measure the actual inner cavity width between the two first steel templates 41, and then compare this actual inner cavity width with the designed forming width. When the actual inner cavity width is greater than the designed forming width, increase the preload of the tie rod 43 to bring the two first steel templates 41 closer together; when the actual inner cavity width is less than the designed forming width, decrease the preload at the corresponding position or check whether the cutting edge 411 is excessively deflected inward. In this way, the tie rod 43 participates in both the stress distribution and dimensional control of the template system.

[0082] Step S8: Perform layered pouring and compensate for the displacement of the formwork.

[0083] After the closed formwork system passes inspection, concrete is poured into the space enclosed by the steel formwork assembly 4. Concrete should preferably be poured in layers. After each layer is poured, the displacement of the top of the first steel formwork 41, the gap at the middle socket of the first steel formwork 41, the embedment status of the cutting edge 411, and the pre-tightening status of the tie rod 43 are re-measured. This re-measurement process is used to determine whether the lateral pressure of the concrete causes the formwork to bulge outwards, slip at the bottom, or loosen in the middle guide.

[0084] When it is detected that the top opening of the first steel formwork 41 is offset outward, it can be compensated by increasing the preload of the tie rod 43 at the corresponding height. When it is detected that the gap at the middle of the first steel formwork 41 is increased, it can be checked whether the cross pile 3 is offset, and the guiding fit between the first steel formwork 41 and the cross pile 3 can be restored by temporary support or local wedging. When it is detected that there is a tendency for the bottom to move outward near the cutting edge 411, the pouring can be suspended, the soil outside the cutting edge 411 can be compacted, or temporary wedges can be set outside the cutting edge 411, and the pouring can continue after the bottom of the formwork is stable.

[0085] The logic of layered pouring compensation control includes:

[0086] After each layer of concrete is poured, the measured displacement of the formwork is compared with the allowable displacement.

[0087] If the measured displacement is within the allowable range, then continue pouring the next layer;

[0088] If the measured displacement exceeds the allowable range, first determine whether the offset occurs at the top, middle or bottom, and then correct it by adjusting the sliding fit position of the tie rod 43, the cross stake 3 or the embedded state of the cutting foot 411.

[0089] This compensation control logic combines quality control during the pouring process with the structural characteristics of the formwork, enabling the formwork to be dynamically adjusted as it withstands gradually increasing lateral pressure from the concrete.

[0090] Step S9: Deformation, pile removal, and backfilling.

[0091] After the concrete reaches the conditions for demolding, first release the tie rods 43, then remove the connecting bolts between the first steel formwork 41 and the second steel formwork 42. When removing the first steel formwork 41, it can be lifted upwards along the opposite direction of the guide edge of the cross pile 3, causing the middle socket of the first steel formwork 41 to slide upwards along the cross pile 3, while simultaneously causing the bottom cutting edge 411 to detach from the bottom of the trench. Since the first steel formwork 41 and the cross pile 3 are slidably connected, there is no need to pry extensively between the trench sidewall and the formwork during demolding, which reduces disturbance to the edges of the already formed concrete.

[0092] After the first steel formwork 41 is removed, the second steel formwork 42 is then removed. If the cross pile 3 needs to be reused, it can be pulled out after the formwork is removed, and the holes formed by pulling out the cross pile 3 and the local gaps formed by inserting the cutting edge 411 should be backfilled and compacted. If the cross pile 3 is used as a temporary component and is not pulled out, the exposed part can be cut off according to the project requirements, and the surrounding area can be treated. When backfilling, the narrow gaps formed by inserting the cutting edge 411 should be filled first to avoid local settlement in the subsequent trench backfill area.

[0093] Example 2

[0094] This embodiment is basically the same as embodiment 1, except that a digital detection method is introduced in steps S3 and S8 to improve the efficiency of installation verification of cross pile 3 and steel formwork assembly 4.

[0095] Specifically, after the cross piles 3 are installed, the spatial positions of the top point, middle guide edge point, and bottom fixed point of the cross piles 3 are obtained using a total station or 3D scanning device. By connecting the spatial points at different heights of the same cross pile 3, the actual axis of the cross pile 3 can be obtained; by comparing this actual axis with the designed vertical line, the verticality deviation of the cross pile 3 can be obtained. By obtaining the spatial positions of the guide edges of adjacent cross piles 3, it can be determined whether there will be local broken lines or misalignments after the first steel formwork 41 is installed.

[0096] After the steel formwork assembly 4 is installed, several inspection points can be set along the top edge of the formwork, and the positions of each inspection point before pouring are recorded. During the layered pouring process, the positions of these inspection points are re-measured after each layer is poured. If a certain inspection point moves outward relative to its position before pouring, the amount of outward movement is compared with the preset allowable value. If the outward movement does not exceed the allowable value, pouring continues; if the outward movement exceeds the allowable value, the adjacent tie rods 43 or the local inspection blade 411 are adjusted to secure the inspection points according to their height and length.

[0097] This digital inspection method does not change the basic construction process of this invention; its function is to replace or supplement manual straightedge and string line inspection with data-driven verification. For long-distance trench construction, digital inspection can quickly identify local offsets in the formwork system, allowing correction work to focus on abnormal sections without needing to readjust the entire formwork section.

[0098] Example 3

[0099] This embodiment is basically the same as embodiment 1, except that the embedding method of the cutting foot 411 is adapted for different groove bottom conditions.

[0100] When the bottom of the foundation pit trench 1 is relatively soft soil, the cutting edge 411 can be inserted to a greater depth. Before the first steel formwork 41 slides down, the insertion area of ​​the cutting edge 411 is slightly pre-compressed or locally leveled so that the surrounding soil can form a wrapping constraint after the cutting edge 411 is inserted. At this time, the cutting edge 411 mainly provides anti-sliding capacity through lateral compression of the soil.

[0101] When the bottom of the foundation pit trench 1 is relatively hard soil or the area covered by the poured concrete cushion 2 is large, a cutting edge insertion groove can be reserved at the edge of the concrete cushion 2. When the first steel formwork 41 slides down, the cutting edge 411 enters the reserved groove, and the reserved groove can be partially filled with fine stone concrete, mortar, or wedges. At this time, the cutting edge 411 mainly provides anti-slip capability by limiting the side wall of the reserved groove.

[0102] When the elevation difference at the bottom of the trench is large, the insertion depth correction of the cutting edge 411 can be incorporated into the control relationship in step S1. The logic is as follows: first, measure the actual elevation of the concrete cushion layer 2 or the bottom of the trench at different pile positions, and then compare it with the design elevation; for positions with lower elevations, appropriately reduce the sliding amount of the first steel formwork 41 or increase the bottom shimming, and for positions with higher elevations, appropriately increase the local trenching depth to ensure that the top openings of adjacent first steel formwork 41 are consistent. This treatment method can avoid the formation of uneven top openings of the steel formwork assembly 4 due to uneven trench bottoms.

[0103] Example 4

[0104] This embodiment is basically the same as Embodiment 1, except that the preload control method of the pull screw 43 is optimized.

[0105] In this embodiment, the tie rods 43 are arranged in three layers: upper, middle, and lower. Before pouring, the middle layer tie rods 43 are first tightened to ensure that the center spacing of the first steel templates 41 on both sides reaches the designed forming width. Then, the lower layer tie rods 43 are tightened to stabilize the template spacing near the bottom cutting edge 411. Finally, the upper layer tie rods 43 are tightened to ensure that the top spacing of the template is consistent with the middle and bottom spacing. The advantage of this sequence is that the middle position is guided and constrained by the cross piles 3, and is usually closer to the design reference. Locking the middle position first as the reference reduces the cumulative deviation of the upper and bottom positions.

[0106] During the pouring process, if the upper layer detection point moves outward while the middle and lower layers remain stable, the preload of the upper layer tie rod 43 is primarily increased. If the middle layer detection point moves outward, the sliding fit clearance between the cross pile 3 and the first steel formwork 41 is checked simultaneously. If the lower layer detection point moves outward, the embedment status of the cutting edge 411 is checked first, and then the lower layer tie rod 43 is adjusted. This method ensures that the adjustment of the tie rod 43 corresponds to the deformation source at different heights of the formwork, improving the correction efficiency during the pouring process.

[0107] It should be noted that the specific dimensions of the cross pile 3, the first steel formwork 41, the second steel formwork 42, the cutting edge 411, and the tie rod 43 can be determined based on the depth of the foundation pit trench 1, the trench width, the concrete pouring height, the soil type, and the construction load. The specific strength calculations, stability calculations, and selection of connector specifications can employ conventional formwork engineering calculation methods in this field; therefore, this invention will not elaborate on the specific calculation formulas. This invention focuses on using the cross pile 3 as a sliding guide reference, the cutting edge 411 as a bottom embedding structure, and the tie rod 43 as a spacing check and lateral pressure adjustment component, and forming a closed loop for formwork installation and pouring correction based on the test results.

[0108] It should also be noted that the fit between the central socket of the first steel formwork 41 and the guide edge of the cross pile 3 can be a clearance fit or a sliding fit with guide shims; the socket can be located in the middle of the back of the first steel formwork 41 or in the reinforcing rib corresponding to the cross pile 3; the guide edge of the cross pile 3 can be directly used as a bearing, or additional guide rails or protrusions can be provided on its edge. As long as the first steel formwork 41 can slide along the vertical direction of the cross pile 3 and be subject to lateral restraint, it can be considered an equivalent embodiment of the present invention.

[0109] Compared with existing technologies, in this embodiment, the concrete cushion layer 2 and the cross piles 3 first form a stable installation benchmark. The first steel formwork 41 is slidably installed along the cross piles 3 through the central socket and secured by the bottom cutting edge 411, allowing the formwork to be positioned in the narrow trench without complex external supports. Three-point detection at the top, central socket, and bottom cutting edge allows for differentiation of the source of formwork offset and corresponding corrective measures. The formwork spacing is checked and adjusted using tie rods 43, and compensation control is implemented based on formwork displacement during layered pouring, reducing the risk of formwork offset caused by pouring lateral pressure. This method combines formwork support, positioning, securing, correction, and pouring monitoring into a continuous construction process, simplifying trench formwork steps and improving concrete forming quality.

[0110] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process may be rearranged without departing from the scope of this disclosure. The appended method claims provide elements of various steps in an exemplary order and are not intended to limit the scope to the specific order or hierarchy described.

[0111] In the detailed description above, various features are combined together in a single embodiment to simplify this disclosure. This approach to disclosure should not be construed as reflecting an intention that embodiments of the claimed subject matter require more features than are explicitly stated in each claim. Rather, as reflected in the appended claims, the invention is presented with fewer features than all of the features in a single disclosed embodiment. Therefore, the appended claims are hereby explicitly incorporated into the detailed description, with each claim representing a separate preferred embodiment of the invention.

[0112] The foregoing description includes examples of one or more embodiments. It is certainly impossible to describe all possible combinations of components or methods in order to describe the above embodiments, but those skilled in the art will recognize that further combinations and arrangements of the various embodiments are possible. Therefore, the embodiments described herein are intended to cover all such changes, modifications, and variations that fall within the scope of the appended claims. Furthermore, the term "comprising" as used in the specification or claims is interpreted in a manner similar to the term "including," as interpreted when used as a conjunction in the claims. Additionally, the use of any term "or" in the specification of the claims is intended to mean "non-exclusive or."

Claims

1. A method for constructing a trench steel formwork with embedded blade foot, characterized in that, Includes the following steps: S1. Based on the design and forming edge line of the foundation pit trench, the size of the steel formwork components and the insertion depth of the cutting edge, establish the installation control relationship between the cross pile and the forming surface of the formwork. S2, a concrete cushion layer is formed at the bottom of the trench, and cross piles are set according to the installation control relationship; S3, detect the guiding status of the cross pile and generate template installation correction amount based on the guiding status; S4, make the first steel formwork slide down along the cross pile to the installation position, and insert the bottom cutting edge of the first steel formwork into the bottom of the trench; S5, posture correction is performed based on the top position, middle socket position and bottom cutting edge position of the first steel formwork; S6, Install the second steel formwork and tie rods to form a closed formwork system; S7, pour concrete, and adjust according to the displacement of the top of the first steel formwork, the gap at the middle socket, the embedded state of the cutting edge, or the pre-tightening state of the tie rod.

2. The method for casting a steel formwork for a groove with embedded cutting edge as described in claim 1, characterized in that, The installation control relationship includes the correspondence between the design forming edge line of the concrete structure, the inner forming surface of the first steel formwork, the position of the middle bearing slot of the first steel formwork, and the center line of the cross pile. The installation control relationship is obtained by progressively deducing from the design forming edge line to the center line of the cross pile.

3. The method for casting a grooved steel formwork with embedded cutting edge as described in claim 1, characterized in that, Positioning holes for inserting cross piles are formed in the concrete cushion layer, or cross piles are inserted before the concrete cushion layer initially sets, so that the lower end of the cross pile is fixed to the concrete cushion layer, and the guide edge of the cross pile is oriented toward the middle support slot of the first steel formwork.

4. The method for casting a steel formwork for a groove with embedded cutting edge as described in claim 1, characterized in that, The guiding status includes the axial deviation of the cross piles, the orientation deviation of the guiding edge, and the spacing deviation between adjacent cross piles. The template installation correction amount is generated based on the deviation of the guiding status relative to the installation control relationship.

5. The method for constructing a grooved steel formwork with embedded cutting edge as described in claim 4, characterized in that, The template installation correction includes the lateral correction of the first steel template, the correction of the lowering height, the correction of the cutting edge pressing depth, and the correction of the tie rod preload.

6. The method for casting a trench steel formwork with embedded cutting edge as described in claim 1, characterized in that, When the first steel formwork slides down along the cross pile, the middle bearing slot of the first steel formwork forms a sliding connection with the guide edge of the cross pile. The sliding connection restricts the lateral swing of the first steel formwork, and the cutting edge is inserted into the bottom of the trench to restrict the bottom slippage of the first steel formwork.

7. The method for casting a steel formwork for a groove with embedded cutting edge as described in claim 1, characterized in that, The attitude correction includes determining the upper offset state of the first steel template based on the top position, determining the sliding fit state between the first steel template and the cross pile based on the middle guide position, determining the cutting edge embedding state based on the bottom embedding position, and selecting the corresponding correction action based on the upper offset state, sliding fit state, and cutting edge embedding state.

8. The method for casting a steel formwork for a groove with embedded cutting edge as described in claim 1, characterized in that, After the closed template system is formed, the end verticality, end joints, inner cavity width and diagonal dimensions of the second steel template are checked, and the inner cavity width between the two first steel templates is verified by the effective length of the tie rod.

9. The method for casting a steel formwork for a groove with embedded cutting edge as described in claim 1, characterized in that, When pouring concrete, after each layer is poured, check the displacement of the top of the first steel formwork, the gap at the middle socket, the embedment status of the cutting edge, and the pre-tightening status of the tie rods. When the displacement of the top exceeds the allowable displacement, adjust the tie rods. When the gap at the middle socket increases, adjust the sliding connection status between the first steel formwork and the cross pile. When the bottom of the cutting edge shows a tendency to move outward, stop pouring and compact or wed the outside of the cutting edge.

10. The method for casting a steel formwork for a groove with embedded cutting edge as described in claim 1, characterized in that, During demolding, the first steel formwork is slid vertically in the opposite direction of the cross pile to release the sliding connection between the first steel formwork and the cross pile, and the second steel formwork and cross pile are removed after the cutting edge is removed from the bottom of the trench.

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