An inflatable steel formwork suitable for narrow spaces and its construction method

Abstract

The present application relates to an inflatable steel formwork suitable for a narrow space and a construction method thereof, which comprises: two oppositely arranged panels; a plurality of spaced support assemblies arranged between the two panels, each support assembly comprising: a support member fixed to the inner side of the panel, the support members of adjacent panels being arranged in a staggered manner and having an overlapping area on the horizontal projection plane; a limiter disposed in the overlapping area of ​​the support members of adjacent panels; and an expansion member disposed between adjacent support assemblies. When erecting the formwork, the expansion member is expanded to resist the lateral pressure during the concrete pouring and curing process; after the concrete reaches the demolding strength, the expansion member is released, the limiter is removed, the panel is separated from the concrete, and the panel is removed by dragging it horizontally to improve the utilization rate of the formwork.

Description

Technical Field

[0001] The present application relates to the technical field of bridge concrete formwork, and in particular to an inflatable steel formwork suitable for narrow spaces and a construction method thereof. Background Art

[0002] Cable-stayed and suspension bridges, with their long spans and unique shapes, are key bridge forms for crossing complex terrain. The main tower, the core load-bearing component, often has separate piers and columns. To enhance the landscape, the gap between the columns and piers is kept small.

[0003] In actual construction, the main tower columns are typically constructed first, followed by the piers. Concrete formwork is required for pouring the piers, but due to the narrow gap between the two, it is difficult to remove the formwork after pouring, resulting in material waste. Furthermore, any remaining formwork in the gap interferes with the lateral free deformation of the main tower columns and piers. During operation, bridges are subject to deformation caused by various loads. Formwork restricts this deformation, affecting the overall load-bearing performance of the main tower. This can accelerate structural fatigue damage over the long term, compromising bridge safety and durability. Summary of the Invention

[0004] The embodiment of the present application provides an inflatable steel formwork suitable for narrow spaces to solve the problem that during the pier casting process, the formwork is difficult to remove after casting due to the narrow gap between the main tower column and the pier, resulting in material waste.

[0005] In a first aspect, an inflatable steel formwork suitable for use in a narrow space is provided, comprising:

[0006] Two panels set opposite each other;

[0007] A plurality of spaced support assemblies are disposed between the two panels, each support assembly comprising:

[0008] - support members fixed to the inner side of the panels, the support members of adjacent panels being arranged in a staggered manner and having overlapping areas in a horizontal projection plane;

[0009] - a limiter, provided in the overlapping area of ​​adjacent panel supports, for limiting the distance between the two panels;

[0010] An expansion member is arranged between adjacent support components.

[0011] In some embodiments, the support member includes two first supporting ribs arranged in parallel;

[0012] The ends of the two first supporting ribs are vertically connected through the second supporting rib;

[0013] The opposite ends of the second supporting ribs of the adjacent supporting members extend beyond the first supporting ribs to form a limiting cavity;

[0014] The limiting component is assembled in the limiting cavity.

[0015] In some embodiments, a fastening steel pipe is provided in the support member, and a fastening steel rod is passed through the fastening steel pipe.

[0016] In some embodiments, sliding pads are provided at the bottom of the two panels.

[0017] In some embodiments, one end of the support member of one panel extends beyond the edge of the panel and the other end is located within the edge of the panel;

[0018] The opposite end of the support member of the other panel extends beyond the edge of the corresponding side panel, and the other end is located inside the edge of the panel.

[0019] In some embodiments, the expansion member is an airbag.

[0020] In some embodiments, the expansion member is a water bladder.

[0021] In some embodiments, the thickness of the limiter is calculated as follows:

[0022] T=2*h-(H-2*T1);

[0023] Where, T is the thickness of the limiter;

[0024] h is the height of the first supporting rib;

[0025] H is the width of the designed concrete gap;

[0026] T1 is the thickness of the panel.

[0027] In a second aspect, a construction method for an inflatable steel formwork suitable for a narrow space is provided, comprising the following steps:

[0028] Process the template according to the design parameters;

[0029] Assemble the two side panels, insert the fastening steel rods into the fastening steel pipes, tension and apply pre-tightening force at both ends to ensure a firm connection between the formwork, anchor the fastening steel rods with anchors, and insert the limiters between the support members of the two side panels;

[0030] placing an expansion member between adjacent support components and expanding the expansion member;

[0031] pouring concrete;

[0032] After the concrete reaches the designed demoulding strength, the expansion piece is contracted, the expansion piece and the limit piece are pulled out, and the panel is moved out of the gap between the concrete.

[0033] The embodiment of the present application provides an inflatable steel formwork suitable for narrow spaces. A plurality of support assemblies and expansion members are arranged at intervals between two panels. Support members are staggered on the inner surface of the panels, and the support members on different panels have overlapping areas. By placing limiters of different thicknesses in the overlapping areas, the formwork can be adapted to different concrete pouring gaps. When the formwork is erected, the expansion members are expanded to resist the lateral pressure during the concrete pouring and curing process. After the concrete reaches the demolding strength, the expansion members are released, the limiters are removed, the panels are separated from the concrete, and the panels are removed by dragging them laterally, thereby improving the utilization rate of the formwork. At the same time, the existence of the gap allows the tower columns and piers to deform freely laterally, optimizes the overall stress performance of the main tower, and improves the safety and durability of the bridge. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0035] Figure 1 A schematic diagram of a vertical cross-sectional structure of an inflatable steel formwork suitable for a narrow space provided in an embodiment of the present application;

[0036] Figure 2 for Figure 1 A in the middle is an enlarged structural diagram;

[0037] Figure 3 for Figure 1 The enlarged structural diagram at B in the middle;

[0038] Figure 4 A schematic plan view of one panel of an inflatable steel formwork suitable for a narrow space provided in an embodiment of the present application;

[0039] Figure 5 A schematic plan view of another panel of the inflatable steel formwork suitable for narrow spaces provided in an embodiment of the present application.

[0040] In the figure: 1. Panel; 2. Support assembly; 201. Support member; 2011. First support rib; 2012. Second support rib; 202. Limit member; 203. Limit cavity; 204. Fastening steel pipe; 205. Fastening steel rod; 3. Expansion member; 4. Sliding pad; 5. Concrete. DETAILED DESCRIPTION

[0041] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0042] The embodiment of the present application provides an inflatable steel formwork suitable for narrow spaces to solve the problem that during the pier casting process, the formwork is difficult to remove after casting due to the narrow gap between the main tower column and the pier, resulting in material waste.

[0043] like Figures 1 to 5 As shown, an inflatable steel formwork suitable for narrow spaces, comprising:

[0044] Two panels 1 arranged opposite to each other;

[0045] A plurality of spaced support assemblies 2 are provided between the two panels 1, each support assembly 2 comprising;

[0046] - Support members 201, fixed to the inner side of the panel 1, the support members 201 of adjacent panels 1 are arranged in a staggered manner and have overlapping areas on the horizontal projection plane;

[0047] - a limiting member 202, which is provided in the overlapping area of ​​the supporting members 201 of adjacent panels 1 and is used to limit the distance between the two panels 1;

[0048] The expansion member 3 is arranged between adjacent support components 2 .

[0049] Each formwork contains two panels 1, and the overall structure of the formwork is made of welded or assembled steel plates and steel sections. A plurality of support assemblies 2 and expansion members 3 are arranged between the two panels 1 along the Z axis. Support members 201 are staggered on the inner surface of the panel 1, and the support members 201 on different panels 1 have overlapping areas. By placing limit members 202 of different thicknesses in the overlapping area, the formwork can be adapted to different concrete pouring gaps. When the formwork is erected, the expansion members 3 are expanded to resist the lateral pressure during the concrete pouring and curing process; after the concrete reaches the demolding strength, the expansion members 3 are released, the limit members 202 are removed, the panel 1 is separated from the concrete, and the panel 1 is removed by dragging it laterally to improve the utilization rate of the formwork. At the same time, the existence of the gap allows the tower column and pier to deform freely laterally, optimizes the overall stress performance of the main tower, and improves the safety and durability of the bridge.

[0050] Specifically, the support member 201 includes two first support ribs 2011 arranged in parallel; the ends of the two first support ribs 2011 are vertically connected by a second support rib 2012;

[0051] The opposite ends of the second supporting ribs 2012 of the adjacent supporting members 201 extend beyond the first supporting ribs 2011 to form a limiting cavity 203 ; the limiting member 202 is assembled in the limiting cavity 203 .

[0052] like Figure 2 As shown, assuming that the left panel is the first panel and the right panel is the second panel, support members 201 are provided on both the first panel and the second panel, wherein the support member 201 of the first panel is located above the support member 201 of the second panel. The support member 201 includes a U-shaped rib formed by two first support ribs 2011 and one second support rib 2012, wherein the lower end of the second support rib 2012 of the first panel extends out of the first support rib 2011, and the upper end of the second support rib 2012 of the second panel extends out of the first support rib 2011. The extended structures of the two together enclose a limiting cavity 203 for accommodating the limiting member 202. The limiting member 202 is a steel plate structure, and its thickness T can be determined according to the designed concrete gap width H, the thickness T1 of the panel 1, and the height h of the first support rib 2011, as shown in FIG. Figure 3 As shown, the specific calculation method is:

[0053] T=2*h-(H-2*T1);

[0054] Wherein, T is the thickness of the limiting member 202;

[0055] h is the height of the first supporting rib 2011, which is a fixed known value;

[0056] H is the designed concrete 5 gap width, which can be measured according to actual project requirements;

[0057] T1 is the thickness of panel 1, which is a fixed known value.

[0058] By setting the thickness of the limiting member 202, it is ensured that the template is suitable for different concrete pouring gaps.

[0059] In this embodiment, the expansion member 3 is an airbag, specifically, the expansion member 3 is a rubber airbag.

[0060] When erecting the formwork, air at different pressures is filled into the rubber airbag according to the position of the rubber airbag and the different concrete pouring heights to resist the lateral pressure during the concrete pouring and curing process, effectively limiting the deformation of the panel 1 under the lateral pressure of the concrete 5, making the surface of the concrete 5 smoother; after the concrete 5 reaches the demolding strength, the air in the rubber airbag is released to separate the formwork from the concrete 5, making it easier to demold.

[0061] In some optional embodiments, the expansion member 3 is a water bag.

[0062] like Figure 2As shown, a fastening steel tube 204 is installed within the support member 201, and a fastening steel rod 205 is inserted into the fastening steel tube 204. The fastening steel tube 204 is welded within the U-shaped cavity of the support member 201 and welded to the second support rib 2012 or the panel 1. Preferably, to ensure uniform force distribution, the sidewalls of the fastening steel tube 204 are welded to the center of the second support rib 2012. The fastening steel tube 204 is installed within the support member 201 of the panel 1, and the fastening steel rod 205 is inserted into the fastening steel tube 204. The fastening steel rod 205 is tensioned at both ends to apply pre-tightening force to the formwork, ensuring a secure connection between adjacent formworks.

[0063] Furthermore, one end of the support member 201 of one panel 1 extends beyond the edge of the panel 1, and the other end is located inside the edge of the panel 1; the opposite end of the support member 201 of the other panel 1 extends beyond the edge of the corresponding side panel 1, and the other end is located inside the edge of the panel 1. Figure 4 and Figure 5 As shown, the support member 201 of one panel 1 is retracted on the left and extended on the right, while the support member 201 of the other panel 1 is retracted on the right and extended on the left. By staggering the support members 201 and the panels 1 left and right, a mother-child structure is formed, which facilitates positioning and connection between templates.

[0064] Further, such as Figure 2 As shown, sliding pads 4 are provided at the bottom of the two panels 1. In order to facilitate the removal of the template, sliding pads 4 are provided below the two panels 1 to reduce the friction during the sliding process of the template and ensure that the template can be smoothly dragged out of the concrete gap horizontally.

[0065] The present application also provides a construction method for an inflatable steel formwork suitable for a narrow space, comprising the following steps:

[0066] S1: Process the template according to the design parameters.

[0067] That is, the thickness T of the limiting member 202 is determined according to the designed concrete gap width H, the thickness T1 of the panel 1 , and the height h of the first supporting rib 2011 .

[0068] S2: Assemble the two side panels 1, insert the fastening steel rod 205 into the fastening steel pipe 204, tension and apply pre-tightening force at both ends to ensure a firm connection between the templates, use anchors to anchor the fastening steel rod 205, and insert the limiter 202 between the support members 201 of the two side panels 1.

[0069] After determining the parameters in step 1, insert the sliding pads 4, join the two panels 1 together, and bolt the sliding pads 4 to the panels 1. Multiple formwork is placed based on the depth of the concrete gap (i.e., along the Y-axis). Because one end of the support member 201 of panel 1 extends beyond the edge of panel 1 and the other end is located within the edge of panel 1, positioning and connection between adjacent panels 1 is facilitated.

[0070] A fastening steel rod 205 is inserted into the fastening steel pipe 204, and the fastening steel rod 205 is tensioned at both ends to apply a pre-tightening force to the formwork to ensure a firm connection between the formworks, and the fastening steel rod 205 is anchored with an anchor.

[0071] The limiting member 202 is inserted between the supporting members 201 on both sides.

[0072] S3: placing an expansion member 3 between adjacent support components 2 and expanding the expansion member 3.

[0073] An airbag is placed between the support components 2 and is inflated to a corresponding pressure value according to the center height of the airbag.

[0074] S4: After the formwork is completed, pour concrete 5.

[0075] S5: After the concrete 5 reaches the designed demoulding strength, the expansion member 3 is contracted, the expansion member 3 and the limiting member 202 are pulled out, and the panel 1 is moved out of the gap between the concrete 5.

[0076] After the concrete 5 reaches the demolding strength, the air in the airbag is released to separate the formwork from the concrete surface and the airbag is pulled out; the limiter 202 is pulled out; the formwork is dragged along the Y-axis direction to move the formwork out of the concrete gap; the pre-tightening force of the fastening steel rod 205 is released and the fastening steel rod 205 is pulled out; finally, the sliding pad is pulled out to achieve the complete removal of the concrete formwork in a small space.

[0077] The present invention provides lateral pressure for fluid concrete through an inflatable rubber airbag and supports the entire surface of the formwork panel 1, effectively limiting the deformation of the panel 1 and ensuring the flatness of the surface of the concrete 5; after the concrete 5 reaches the demolding strength, the air in the airbag is released to separate the formwork from the concrete surface; a sliding pad 4 is provided at the bottom of the formwork to ensure that the formwork can be smoothly dismantled and removed; it is easy to design and manufacture, has a simple principle, and is easy to operate, and has obvious advantages for concrete pouring operations in narrow spaces.

[0078] In the description of this application, it should be noted that the terms "upper" and "lower" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be internal communication between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0079] It should be noted that, in this application, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element.

[0080] The foregoing is merely a list of specific embodiments of the present application, intended to enable those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the broadest scope consistent with the principles and novel features of the present application.

Claims

1. An inflatable steel formwork suitable for narrow spaces, characterized in that: It includes: Two panels (1) arranged opposite to each other; A plurality of spaced-apart support assemblies (2) are disposed between the two panels (1), each support assembly (2) comprising: - support members (201) fixed to the inner side of the panel (1), the support members (201) of adjacent panels (1) being arranged in a staggered manner and having overlapping areas on a horizontal projection plane; - a limiting member (202), arranged in the overlapping area of ​​the supporting members (201) of adjacent panels (1), for limiting the distance between the two panels (1); An expansion piece (3) is arranged between adjacent support components (2).

2. The inflatable steel formwork suitable for narrow spaces as claimed in claim 1, characterized in that: The support member (201) comprises two first supporting ribs (2011) arranged in parallel; The ends of the two first supporting ribs (2011) are vertically connected via the second supporting rib (2012); The opposite ends of the second supporting ribs (2012) of the adjacent supporting members (201) extend beyond the first supporting ribs (2011) to form a limiting cavity (203); The limiting member (202) is assembled in the limiting cavity (203).

3. The inflatable steel formwork suitable for narrow spaces as claimed in claim 2, characterized in that: A fastening steel pipe (204) is provided in the support member (201), and a fastening steel rod (205) is passed through the fastening steel pipe (204).

4. The inflatable steel formwork suitable for narrow spaces as claimed in claim 1, characterized in that: Sliding pads (4) are provided at the bottom of the two panels (1).

5. The inflatable steel formwork suitable for narrow spaces as claimed in claim 1, characterized in that: One end of the support member (201) extends beyond the edge of the panel (1), and the other end is located within the edge of the panel (1); The opposite end of the support member (201) of the other panel (1) extends beyond the edge of the corresponding side panel (1), and the other end is located within the edge of the panel (1).

6. The inflatable steel formwork suitable for narrow spaces as claimed in claim 1, characterized in that: The expansion piece (3) is an air bag.

7. The inflatable steel formwork suitable for narrow spaces as claimed in claim 1, characterized in that: The expansion piece (3) is a water bag.

8. The inflatable steel formwork suitable for narrow spaces as claimed in claim 2, characterized in that: The thickness of the limiting member (202) is calculated as follows: T=2*h-(H-2*T1); Wherein, T is the thickness of the limiting member (202); h is the height of the first supporting rib (2011); H is the design concrete (5) gap width; T1 is the thickness of the panel (1).

9. A construction method for an inflatable steel formwork suitable for a narrow space, using the inflatable steel formwork suitable for a narrow space as claimed in claim 3, characterized in that: The steps include: Process the template according to the design parameters; Assemble the two side panels (1), insert the fastening steel rod (205) into the fastening steel pipe (204), tension and apply pre-tightening force at both ends to ensure that the connection between the templates is firm, anchor the fastening steel rod (205) with an anchor, and insert the limiter (202) between the support members (201) of the two side panels (1); placing an expansion member (3) between adjacent support assemblies (2) and expanding the expansion member (3); pouring concrete (5); After the concrete (5) reaches the designed demoulding strength, the expansion member (3) is contracted, the expansion member (3) and the limiting member (202) are pulled out, and the panel (1) is moved out of the gap between the concrete (5).

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