A mortise and tenon 3D printed concrete wall column connection structure and its construction method

Abstract

The present invention provides a 3D-printed concrete wall-column connection structure with mortise and tenon joints and a construction method thereof. The structure comprises a 3D-printed concrete wall formwork assembly, a 3D-printed load-bearing column formwork, a wall reinforcement mesh and a load-bearing column reinforcement cage, post-cast concrete, and a UHPC reinforced concrete layer. The 3D-printed load-bearing column formwork is provided with a connection area at the top. The 3D-printed concrete wall formwork assembly comprises multiple wall formworks, each of which has a connection portion that interlocks with the mortise and tenon joints in the connection area to form a columnar structure that matches the 3D-printed load-bearing column formwork. Load is transferred through mechanical connection and geometric interaction between the components. This interlocking structure increases the contact area and utilizes shape constraints to improve the shear resistance of the interface. UHPC filling is then used to further enhance the strength and rigidity of the connection structure. This not only increases connection reliability but also saves costs, achieving industrialized and green modern construction and forming a sustainable building model.

Description

Technical Field

[0001] The present invention relates to the technical field of building structures, and in particular to a mortise and tenon 3D printed concrete wall column connection structure and a construction method thereof. Background Art

[0002] 3D-printed concrete, a revolutionary application of additive manufacturing in the construction field, has experienced rapid development in recent years. It is estimated that this technology can save 50-80% of labor costs, reduce construction waste by 30-60%, and completely eliminate formwork costs. In 3D-printed structural systems, the connection between load-bearing columns and walls is critical to ensuring structural integrity and safety. The complex stress conditions in the wall-column joint area require that the connection design not only meet strength requirements but also consider ductility, durability, and construction feasibility. However, the interface between 3D-printed layers presents a potential weak link, particularly when subjected to shear and tensile stresses, and its bond strength directly affects the overall mechanical properties of the structure. Furthermore, implementing effective alternative reinforcement measures in the joint area is a major bottleneck in the current technological development. Traditional rebar placement methods often conflict with the automated, continuous printing process. Existing connection methods have significant limitations in terms of structural performance, construction efficiency, and cost-effectiveness. Designing a mortise and tenon joint technology for 3D-printed concrete wall columns with efficient construction and reliable strength is an urgent challenge in the field of building structural technology. Summary of the Invention

[0003] The present invention provides a mortise and tenon 3D printed concrete wall column connection structure and a construction method thereof, aiming to improve at least one of the above-mentioned technical problems.

[0004] In order to solve the above technical problems, the present invention provides a mortise and tenon 3D printed concrete wall column connection structure, comprising a 3D printed concrete wall formwork group, a 3D printed load-bearing column formwork, a wall steel mesh and a load-bearing column steel cage; the top of the 3D printed load-bearing column formwork is axially provided with a connection area; the 3D printed concrete wall formwork group is provided with a plurality of wall formworks connected and arranged on the peripheral sides of the 3D printed load-bearing column formwork, and each wall formwork is constructed with a connection part, and the connection part can be respectively interlocked with the mortise and tenon in the connection area to form a columnar structure matching the 3D printed load-bearing column formwork; the wall steel mesh is used to be implanted in the inner cavity of the wall formwork; the load-bearing column steel cage is used to be implanted in the inner cavity of the 3D printed load-bearing column formwork; it also includes post-cast concrete poured into the inner cavity of the wall formwork and the inner cavity of the 3D printed load-bearing column formwork respectively; a UHPC reinforced concrete layer is also cast on the upper end of the post-cast concrete.

[0005] As a further optimization, the bottom end of the 3D printed load-bearing column formwork extends radially outward with a column foot having the same length as the wall formwork, and the column foot is connected to the bottom end of the wall formwork.

[0006] As a further optimization, a plurality of foot anchoring key teeth are arranged at the top of the column foot, and the foot anchoring key teeth are used to implant and fix the wall steel mesh.

[0007] As a further optimization, the wall reinforcement mesh includes longitudinal reinforcement mesh and transverse reinforcement mesh.

[0008] As a further optimization, the load-bearing column steel cage includes longitudinal steel bars and transverse steel bars.

[0009] As a further optimization, the 3D printed concrete wall formwork group is provided with three wall formworks, namely the first wall formwork, the second wall formwork and the third wall formwork. The three wall formworks are arranged in a T-shape at the side ends of the 3D printed load-bearing column formwork.

[0010] As a further optimization, the first wall formwork, the second wall formwork and the third wall formwork are respectively provided with a first connecting part, a second connecting part and a third connecting part; the first connecting part is used to connect to the lower area of ​​the connection area, the third connecting part is used to connect to the middle area of ​​the connection area, and the second connecting part is used to connect to the upper area of ​​the connection area.

[0011] The present invention also provides a construction method for the mortise and tenon 3D printed concrete wall column connection structure as described in any one of the above, comprising the following steps:

[0012] S1: Printing a 3D printed concrete wall formwork assembly, printing the wall formwork body layer by layer; then, printing the first connecting portion, the second connecting portion, and the third connecting portion extending from the wall formwork body respectively with support surface structure measures;

[0013] S2: Print the 3D printed load-bearing column formwork and tie the wall reinforcement mesh. First, print the column foot and foot anchor key teeth, then print the main structure of the 3D printed load-bearing column formwork layer by layer to form the connection area; a hole must be reserved at the center of the foot anchor key teeth for implanting the longitudinal reinforcement of the reinforcement mesh, and the transverse reinforcement of the reinforcement mesh is tied to form the wall reinforcement mesh;

[0014] S3: Prepare the transverse reinforcement of the steel cage, place the vertical reinforcement of the steel cage around the inner side of the transverse reinforcement of the steel cage at equal intervals and tie them together, then hoist the remaining transverse reinforcement of the steel cage on the vertical reinforcement of the steel cage at equal intervals for positioning, and tie them together in sequence to form the load-bearing column steel cage; and place it in the inner cavity formed by the 3D printed load-bearing column formwork by hoisting and positioning;

[0015] S4: Assemble the 3D printed concrete wall formwork group and the 3D printed load-bearing column formwork, hoist the wall formwork in different directions above the column footings in each direction, then lower it and pass it through the wall reinforcement mesh, and at the same time interlock the connection areas at the top of the 3D printed load-bearing column formwork body through the first connection part, the third connection part, and the second connection part in sequence;

[0016] S5: Fill the post-cast concrete and UHPC reinforced concrete layers into the inner cavity of the wall formwork and the inner cavity of the 3D printed load-bearing column formwork respectively to complete the wall column construction work.

[0017] Among them, when filling the inner cavity of the wall formwork, first use post-cast concrete to fill the inner cavity of the wall formwork to the bottom surface height of the second connection part, and then use the UHPC reinforced concrete layer to fill it to the top of the inner cavity of the wall formwork; when filling the inner cavity of the 3D printed load-bearing column formwork, first use post-cast concrete to fill the inner cavity of the 3D printed load-bearing column formwork to the bottom surface height of the connection area, and then use the UHPC reinforced concrete layer to fill it into the connection area between the first connection part, the third connection part and the second connection part.

[0018] By adopting the above technical solution, the present invention can achieve the following technical effects:

[0019] This application provides a 3D-printed concrete wall-column connection structure with mortise and tenon joints and its construction method. The load-bearing columns and concrete walls are primarily made of 3D-printed concrete, cast-in-place concrete, and ultra-high-performance concrete (UHPC), with steel mesh and cages arranged within them. The construction method uses 3D-printed concrete to form a connection cavity between the load-bearing columns and the concrete wall formwork, then inserts the steel mesh and cage, and then pours post-cast concrete. Loads are transferred through a mechanical connection and the geometric interaction between the components. This interlocking structure increases the contact area and utilizes shape constraints to improve the shear resistance of the interface. At the base of the wall-column joint, shear key principles are employed to print raised anchoring teeth on the column foot connection interface, which are then embedded in the post-cast concrete. At the top of the wall-column joint, the high degree of freedom of 3D printing is utilized to directly print a geometrically interlocking mortise and tenon joint structure on the wall-column contact surface. Furthermore, UHPC is filled into the top of the wall-column joint to further enhance the strength and rigidity of the connection structure. Compared with the traditional 3D printing wall column connection method, it can not only increase the connection reliability, but also save costs, realize the industrialization and greening of modern buildings, and form a sustainable building model. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 This is a schematic diagram of the structure of a mortise and tenon 3D printed concrete wall column connection structure when it is decomposed according to an embodiment of the present invention;

[0022] Figure 2 3D printed load-bearing column formwork according to an embodiment of the present invention;

[0023] Figure 3 3D printing concrete wall formwork assembly according to an embodiment of the present invention;

[0024] Figure 4 Schematic diagram of the structure of the wall reinforcement mesh and the load-bearing column reinforcement cage according to an embodiment of the present invention;

[0025] Figure 5 This is a schematic structural diagram of the assembly and pouring stage of an embodiment of the present invention;

[0026] Figure 6 This is a structural schematic diagram of the UHPC reinforced concrete layer pouring stage according to an embodiment of the present invention;

[0027] Markings in the figure: 1. Wall formwork; 2. 3D-printed load-bearing column formwork; 3. Wall reinforcement mesh; 4. Load-bearing column reinforcement cage; 5. Post-cast concrete; 6. UHPC reinforced concrete layer; 11. First connection; 12. Second connection; 13. Third connection; 21. Connection area; 22. Column foot; 23. Foot anchor key teeth; 31. Longitudinal reinforcement of reinforcement mesh; 32. Transverse reinforcement of reinforcement mesh; 41. Longitudinal reinforcement of reinforcement cage; 42. Transverse reinforcement of reinforcement cage. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention for which protection is sought, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0029] Depend on Figures 1 to 3 As shown, an embodiment of the present invention provides a mortise and tenon 3D-printed concrete wall column connection structure, comprising a 3D-printed concrete wall formwork assembly, a 3D-printed load-bearing column formwork 2, a wall reinforcement mesh 3, and a load-bearing column reinforcement cage 4. A connection region 21 is axially provided at the top of the 3D-printed load-bearing column formwork 2, and multiple protrusions and grooves are formed axially within the connection region 21. The 3D-printed concrete wall formwork assembly is provided with multiple wall formworks 1 connected to the sides of the 3D-printed load-bearing column formwork 2. Each wall formwork 1 is constructed with a connection portion that can interlock with the mortise and tenon of the connection region 21 to form a columnar structure that matches the main body of the 3D-printed load-bearing column formwork 2.

[0030] In this embodiment, the 3D printed concrete wall formwork group is provided with three wall formworks 1, namely the first wall formwork, the second wall formwork and the third wall formwork. The three wall formworks 1 are arranged in a T-shape on the side ends of the 3D printed load-bearing column formwork 2 from three directions.

[0031] Preferably, the first wall formwork, the second wall formwork, and the third wall formwork are respectively provided with a first connecting portion 11, a second connecting portion 12, and a third connecting portion 13; the first connecting portion 11 is used to connect to the lower area of ​​the connection area 21, the third connecting portion 13 is used to connect to the middle area of ​​the connection area 21, and the second connecting portion 12 is used to connect to the upper area of ​​the connection area 21. After being installed and connected from bottom to top, the connecting portion and the connection area 21 can form a complete columnar structure with a closed outer periphery, so that the inner side can be used to fill with concrete, and the wall column connection strength can be greatly enhanced. There are many shapes and structures of the interlocking connection, which will not be described in detail here.

[0032] It should be noted that while this embodiment demonstrates a three-dimensional wall-stud mortise-and-tenon joint structure, it is also applicable to two- and four-dimensional wall-stud mortise-and-tenon joint structures. These two- and four-dimensional wall-stud mortise-and-tenon joint structures require increasing or decreasing the print height of the 3D-printed load-bearing column connection area 21 to ensure proper grouting during the pouring of the ultra-high-performance concrete (UHPC) reinforcement layer. This will not be elaborated upon here.

[0033] Preferably, the wall reinforcement mesh 3 is implanted within the inner cavity of the wall formwork 1, while the load-bearing column reinforcement cage 4 is implanted within the inner cavity of the 3D-printed load-bearing column formwork 2. The wall reinforcement mesh 3 includes longitudinal reinforcement 31 and transverse reinforcement 32. The load-bearing column reinforcement cage 4 includes longitudinal reinforcement 41 and transverse reinforcement 42.

[0034] Furthermore, the wall-stud connection structure of the present application also includes post-cast concrete 5, which is poured into the inner cavities of the wall formwork 1 and the 3D-printed load-bearing column formwork 2, respectively. A UHPC-reinforced concrete layer 6 is also poured above the post-cast concrete 5. In particular, filling the UHPC-reinforced concrete layer 6 between the structure formed by the first connecting portion 11, the second connecting portion 12, and the third connecting portion 13 at the connection area 21 can greatly enhance the wall-stud connection performance.

[0035] Preferably, a column foot 22 having the same length as the wall formwork 1 extends radially outward from the bottom end of the 3D printed load-bearing column formwork 2. The column foot 22 is connected to the bottom end of the wall formwork 1. It should be noted that the inner cavity of the wall formwork 1 is vertically through-through, and the column foot 22 serves as the base of the wall formwork 1 and also seals the bottom of the inner cavity.

[0036] Furthermore, a plurality of foot anchoring teeth 23 are arranged at the top of the column foot 22. The foot anchoring teeth can be embedded in the concrete after pouring to resist the interface shear force. At the same time, the foot anchoring teeth can be used to implant and fix the wall reinforcement mesh 3.

[0037] The present application also provides a construction method of a mortise and tenon 3D printed concrete wall column connection structure as described above, comprising the following steps:

[0038] S1: Printing a 3D printed concrete wall formwork assembly, printing the main body of the wall formwork 1 layer by layer; then, printing the first connecting portion 11, the second connecting portion 12, and the third connecting portion 13 extending from the main body of the wall formwork 1 with support surface structural measures;

[0039] S2: Print the 3D printed load-bearing column formwork 2 and tie the wall reinforcement mesh 3. First, print the column foot 22 and the foot anchor key teeth 23. Then, print the main structure of the 3D printed load-bearing column formwork 2 layer by layer upward to form the connection area 21. A hole must be reserved at the center of the foot anchor key teeth 23 for implanting the longitudinal reinforcement mesh 31, and tie the transverse reinforcement mesh 32 to form the wall reinforcement mesh 3.

[0040] S3: Make the transverse reinforcement 42 of the steel cage, place the vertical reinforcement of the steel cage around the inner side of the transverse reinforcement 42 of the steel cage at equal intervals and tie them together, then hoist the remaining transverse reinforcement 42 of the steel cage at equal intervals on the vertical reinforcement of the steel cage for positioning, and tie them together in sequence to form the load-bearing column steel cage 4; and place it in the inner cavity formed by the 3D printed load-bearing column formwork 2 by hoisting and positioning;

[0041] S4: Assemble the 3D printed concrete wall formwork group and the 3D printed load-bearing column formwork 2, and hoist the wall formwork 1 in different directions above the column foot 22 in each direction, then lower it and pass through the wall reinforcement mesh 3, and at the same time interlock the first connecting part 11, the third connecting part 13 and the second connecting part 12 in sequence at the connection area 21 at the top of the main body of the 3D printed load-bearing column formwork 2;

[0042] S5: Fill the post-cast concrete 5 and the UHPC reinforced concrete layer 6 into the inner cavity of the wall formwork 1 and the inner cavity of the 3D printed load-bearing column formwork 2 respectively to complete the wall column construction work.

[0043] In particular, when filling the inner cavity of the wall formwork 1, first use the post-cast concrete 5 to fill the inner cavity of the wall formwork 1 to the bottom surface height of the second connection part 12, and then use the UHPC reinforced concrete layer 6 to fill it to the top of the inner cavity of the wall formwork 1; when filling the inner cavity of the 3D printed load-bearing column formwork 2, first use the post-cast concrete 5 to fill the inner cavity of the 3D printed load-bearing column formwork 2 to the bottom surface height of the connection area 21, and then use the UHPC reinforced concrete layer 6 to fill it into the connection area 21 between the first connection part 11, the third connection part 13 and the second connection part 12.

[0044] In summary, the load-bearing columns and concrete walls of this application are primarily made of 3D-printed concrete, cast-in-place concrete, and ultra-high-performance concrete (UHPC), with steel mesh and cages arranged within them. The construction method employs 3D-printed concrete to form a connection cavity between the load-bearing columns and the concrete wall formwork 1, implant the steel mesh and cage, and then pour in post-cast concrete 5. Load transfer is achieved through mechanical connection and the geometric interaction between the components. This interlocking structure increases the contact area and utilizes shape constraints to enhance the shear resistance of the interface. At the base of the wall column joint, utilizing the shear key principle, raised foot anchoring teeth 23 are printed on the connection interface of the column foot 22. These are then embedded in the post-cast concrete 5. At the top of the wall column joint, utilizing the high degree of freedom of 3D printing, a geometrically interlocking mortise and tenon structure is directly printed on the wall column contact surface. Furthermore, UHPC is filled into the top of the wall column to further enhance the strength and rigidity of the connection structure. Compared with the traditional 3D printing wall column connection method, it can not only split the structural components for production, transportation and assembly, but also increase the connection reliability, save costs, realize the industrialization and greening of modern buildings, and form a sustainable construction model.

[0045] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A mortise and tenon 3D printed concrete wall column connection structure, characterized in that: Includes 3D printed concrete wall formwork, 3D printed load-bearing column formwork, wall reinforcement mesh and load-bearing column reinforcement cage; A connection area is axially provided at the top end of the 3D printed load-bearing column formwork; The 3D printed concrete wall formwork assembly is provided with a plurality of wall formworks connected to the periphery of the 3D printed load-bearing column formwork, each wall formwork having a connecting portion, the connecting portion being capable of interlocking with the connecting area by mortise and tenon joints to form a columnar structure that matches the 3D printed load-bearing column formwork; the connecting portion and the connecting area form a complete columnar structure, the outer periphery of which is closed, and the inner side is used to fill with concrete; The wall reinforcement mesh is used to be implanted into the inner cavity of the wall formwork; the load-bearing column reinforcement cage is used to be implanted into the inner cavity of the 3D printed load-bearing column formwork; It also includes post-poured concrete poured into the inner cavity of the wall formwork and the inner cavity of the 3D printed load-bearing column formwork respectively; a UHPC reinforced concrete layer is also poured on the upper end of the post-poured concrete.

2. A mortise and tenon 3D printed concrete wall column connection structure according to claim 1, characterized in that The bottom end of the 3D printed load-bearing column formwork radially extends outward with a column foot having the same length as the wall formwork, and the column foot is connected to the bottom end of the wall formwork.

3. A mortise and tenon 3D printed concrete wall column connection structure according to claim 2, characterized in that , a plurality of foot anchoring key teeth are arranged at the top of the column foot, and the foot anchoring key teeth are used to implant and fix the wall steel mesh.

4. A mortise and tenon 3D printed concrete wall column connection structure according to claim 1, characterized in that ,The wall steel mesh includes longitudinal steel bars and transverse steel bars.

5. A mortise and tenon 3D printed concrete wall column connection structure according to claim 1, characterized in that ,The load-bearing column steel cage includes longitudinal steel bars and transverse steel bars of the steel cage.

6. A mortise and tenon 3D printed concrete wall column connection structure according to claim 1, characterized in that The 3D printed concrete wall formwork group is provided with three wall formworks, namely the first wall formwork, the second wall formwork and the third wall formwork. The three wall formworks are arranged in a T-shape at the side ends of the 3D printed load-bearing column formwork.

7. A mortise and tenon 3D printed concrete wall column connection structure according to claim 6, characterized in that The first wall formwork, the second wall formwork and the third wall formwork are respectively provided with a first connecting part, a second connecting part and a third connecting part; the first connecting part is used to connect to the lower area of ​​the connection area, the third connecting part is used to connect to the middle area of ​​the connection area, and the second connecting part is used to connect to the upper area of ​​the connection area.

8. A construction method for a mortise and tenon 3D printed concrete wall column connection structure according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1: Printing a 3D printed concrete wall formwork assembly, printing the wall formwork body layer by layer; then, printing the first connecting portion, the second connecting portion, and the third connecting portion extending from the wall formwork body respectively with support surface structure measures; S2: Print the 3D printed load-bearing column formwork and tie the wall reinforcement mesh. First, print the column foot and foot anchor key teeth, then print the main structure of the 3D printed load-bearing column formwork layer by layer to form the connection area; a hole must be reserved at the center of the foot anchor key teeth for implanting the longitudinal reinforcement of the reinforcement mesh, and the transverse reinforcement of the reinforcement mesh is tied to form the wall reinforcement mesh; S3: Prepare the transverse reinforcement of the steel cage, place the vertical reinforcement of the steel cage around the inner side of the transverse reinforcement of the steel cage at equal intervals and tie them together, then hoist the remaining transverse reinforcement of the steel cage on the vertical reinforcement of the steel cage at equal intervals for positioning, and tie them together in sequence to form the load-bearing column steel cage; and place it in the inner cavity formed by the 3D printed load-bearing column formwork by hoisting and positioning; S4: Assemble the 3D printed concrete wall formwork group and the 3D printed load-bearing column formwork, hoist the wall formwork in different directions above the column footings in each direction, then lower it and pass it through the wall reinforcement mesh, and at the same time interlock the connection areas at the top of the 3D printed load-bearing column formwork body through the first connection part, the third connection part, and the second connection part in sequence; S5: Fill the post-cast concrete and UHPC reinforced concrete layers into the inner cavity of the wall formwork and the inner cavity of the 3D printed load-bearing column formwork respectively to complete the wall column construction work.

9. The construction method of the mortise and tenon 3D printed concrete wall column connection structure according to claim 8 is characterized in that , When filling the inner cavity of the wall formwork, first use post-cast concrete to fill the inner cavity of the wall formwork to the bottom height of the second connecting portion, and then use a UHPC reinforced concrete layer to fill it to the top of the inner cavity of the wall formwork; When filling the inner cavity of the 3D printed load-bearing column formwork, first use post-poured concrete to fill the inner cavity of the 3D printed load-bearing column formwork to the bottom height of the connection area, and then use the UHPC reinforced concrete layer to fill the connection area between the first connection part, the third connection part and the second connection part.

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