Fabricated concrete sandwich wallboard and flexural capacity calculation method

Abstract

The invention relates to the field of fabricated buildings, in particular to a fabricated concrete sandwich wallboard and a flexural capacity calculation method.The fabricated concrete sandwich wallboard comprises a concrete inner acanthus, a heat preservation board and a concrete outer acanthus which are sequentially arranged in a stacked mode from bottom to top, and grid boards parallel to the surface of the heat preservation board are pre-buried in the concrete outer acanthus and the concrete inner acanthus; a tie pipe is arranged in the insulation board in the length direction of the insulation board, the tie pipe comprises two sets of vertical end plates arranged in parallel and two sets of transverse end plates arranged in parallel, the vertical end plates and the transverse end plates define a square pipe type cavity structure, and edge rib plates are arranged on the board faces of the two transverse end plates. And the insulation board is tied with the outer concrete acanthus and the inner concrete acanthus through the edge rib plates on the tying pipes. While the stress performance requirement of the sandwich wallboard is met, the heat bridge effect can be avoided, and light weight of the wallboard is achieved.

Description

Technical Field

[0001] The invention relates to the field of prefabricated buildings, and in particular to a prefabricated concrete sandwich wall panel and a method for calculating the bending bearing capacity. Background Art

[0002] Precast concrete sandwich insulation wall panels are a new type of precast reinforced concrete wall panels that integrate load-bearing and insulation, and are widely used in building exterior walls or interior walls. The existing precast concrete sandwich insulation wall panels, as described in patent number "CN210713502U", include an outer blade, an insulation layer, an inner blade and a tie piece; the outer blade and the inner blade are both made of reinforced concrete, the insulation layer is arranged between the inner and outer blades, and the inner and outer reinforced concrete blades and the insulation layer are combined into one by the tie piece.

[0003] At present, the anchors of traditional sandwich insulation walls are cast-in-place concrete ribs between the inner and outer concrete blades. Although sandwich wall panels using such anchors can have better stress-bearing performance, they are prone to produce a large thermal bridge effect due to the high thermal conductivity of concrete. In order to avoid the occurrence of thermal bridge effects, the anchors of some sandwich wall panels have evolved from cast-in-place concrete ribs to composite material anchors. However, the current conventional composite material anchors are usually rod-shaped anchors or plate-shaped anchors, which have low shear strength and stiffness. The thickness of the outer blades and inner blades in the sandwich wall panels needs to be increased to make the sandwich wall panels meet the design requirements. Although the occurrence of thermal bridge effects can be avoided, it cannot meet the lightweight requirements of sandwich wall panels, so it needs to be solved urgently. Summary of the invention

[0004] In order to avoid and overcome the technical problems existing in the prior art, the present invention provides an assembled concrete sandwich wall panel and a method for calculating the bending bearing capacity. The present invention can meet the mechanical performance requirements of the sandwich wall panel, avoid the generation of thermal bridge effects, and achieve lightweighting of the wall panel.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] An assembled concrete sandwich wall panel comprises a concrete inner blade plate, an insulation board and a concrete outer blade plate which are stacked in sequence from bottom to top; a grid plate arranged parallel to the insulation board surface is pre-embedded in the concrete outer blade plate and the concrete inner blade plate; a tie tube is arranged in the insulation board along the board length direction; the tie tube comprises two groups of vertical end plates arranged in parallel and two groups of horizontal end plates arranged in parallel; the vertical end plates and the horizontal end plates are enclosed to form a square tube type cavity structure; edge ribs are arranged on the board surfaces of the two horizontal end plates; the insulation board is tied to the concrete outer blade plate and the concrete inner blade plate through the edge ribs on the tie tube.

[0007] As a further solution of the present invention: the grid plate includes cross-staggered horizontal limbs and vertical limbs, and the edge ribs are arranged along the symmetry line of the horizontal end plate and connected to one of the vertical limbs of the grid plate.

[0008] As a further solution of the present invention: the tie tubes are evenly spaced in the horizontal direction in the insulation board, and the spacing between adjacent tie tubes is S, 500mm≤S≤700mm.

[0009] As a further solution of the present invention: the wall thickness of the vertical end plate, the horizontal end plate and the edge rib plate is D, 5mm≤D≤10mm.

[0010] As a further solution of the present invention: the thickness of the concrete inner blade plate and the concrete outer blade plate is H, 30mm≤H≤50mm.

[0011] As a further solution of the present invention: the insulation board is made of extruded polystyrene.

[0012] As a further solution of the present invention: the tensile strength of the grid plate is 1400 MPa, and the compressive strength of the concrete outer blade plate and the concrete inner blade plate is 120 MPa.

[0013] A method for calculating the bending bearing capacity of an assembled concrete sandwich wall panel, wherein the ultimate bending bearing capacity of the assembled concrete sandwich wall panel is M u :

[0014]

[0015] Among them, f u is the longitudinal tensile strength of the mesh panel;

[0016] A f is the total cross-sectional area of ​​the longitudinal limbs of the grid plate;

[0017] h0 is the effective height of the sandwich wall panel;

[0018] x is the relative compression zone height of the sandwich panel;

[0019] is the correction factor;

[0020] x1 is the wall thickness of the vertical end plate, transverse end plate and edge rib plate;

[0021] x2 is the cross-sectional length of the edge rib;

[0022] x3 is the cross-sectional length of the transverse end plate.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. The cross-section of the anchor of the present invention is designed to be in the shape of a "Z" character, and has a cavity inside, which effectively increases the heat transfer path and can further reduce the thermal bridge effect. By replacing the traditional steel structure with a composite mesh plate, while meeting the design bearing capacity conditions of the sandwich wall panel, the thickness of the concrete inner blade plate and the concrete outer blade plate can be effectively reduced, making the sandwich wall panel lighter.

[0025] 2. The present invention adopts ultra-high performance concrete to make the anchor, which is integrally formed with the concrete inner blade and the concrete outer blade of the ultra-high performance concrete, and does not require the anchor length of the anchor. Since a composite material grid is used instead of steel bars, there is no hidden danger of steel bar corrosion. At the same time, ultra-high performance concrete anchors are used, so the thickness of the upper and lower blades can be greatly reduced to form a lightweight component.

[0026] 3. The present invention establishes a calculation formula for the ultimate bending bearing capacity of sandwich wall panels suitable for "Z"-shaped anchors, which can quickly calculate the ultimate bending bearing capacity of sandwich wall panels under different working conditions, and is relatively consistent with actual results. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the present invention.

[0028] Figure 2 It is a simulation cloud diagram of the bending state of the present invention.

[0029] Figure 3 It is a data comparison and analysis diagram of the calculated value and the simulated value of the bending bearing capacity of the present invention.

[0030] In the figure:

[0031] 1. Concrete inner blade; 2. Insulation board; 3. Concrete outer blade; 4. Grid board;

[0032] 5. Tie tube; 51. Vertical end plate; 52. Horizontal end plate; 53. Edge rib plate. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] See also Figures 1 to 3In an embodiment of the present invention, a prefabricated concrete sandwich wall panel and a method for calculating the bending bearing capacity include a concrete inner blade 1, an insulation board 2 and a concrete outer blade 3 stacked in sequence from bottom to top, and the concrete inner blade 1 and the concrete outer blade 3 are both ultra-high performance concrete (UHPC). The insulation board 2 is an extruded polystyrene insulation board. A mesh plate 4 is provided in the concrete inner blade 1 and the concrete outer blade 3. The thickness of the concrete inner blade 1 and the concrete outer blade 3 is H, 30mm≤H≤50mm.

[0035] A "m"-shaped groove is pre-opened in the insulation board 2 for inserting the tie tube 5. The tie tube 5 can be pre-processed and inserted into the insulation board 2, or cast in the insulation board 2. The tie tubes 5 are evenly spaced horizontally on the insulation board 2, and the spacing between two adjacent groups of tie tubes 5 is S, 500mm≤S≤700mm, preferably 600mm.

[0036] The sandwich wall panel is cast in one piece. During processing, firstly, one set of mesh panels 4 is tied with pads and placed in the formwork, and then the concrete inner blade 1 is cast. Then the insulation board 2 is placed in the formwork, and finally another set of mesh panels 4 is tied with pads and placed on the insulation board 2, and finally the concrete outer blade 3 and tie pipe 5 are cast. After the curing is completed, it can be applied to the prefabricated building.

[0037] The tie tube 5 includes two sets of parallel vertical end plates 51 and two sets of parallel horizontal end plates 52. The vertical end plates 51 and the horizontal end plates 52 enclose a hollow square tube. An edge rib 53 is arranged on the central axis of the horizontal end plate 52. The edge rib 53 is arranged parallel to the plate surface of the vertical end plate 51. The wall thickness of the vertical end plate 51, the horizontal end plate 52 and the edge rib 53 is D, 5mm≤D≤10mm.

[0038] The grid plate 4 includes cross-staggered horizontal limbs and vertical limbs, each of which is arranged parallel to the tie tube 5 , and one of the vertical limbs is connected to the edge rib 53 of the tie tube 5 .

[0039] Due to the change of the anchors, the calculation formula for the bending capacity in the current specifications is no longer suitable for the calculation of the ultimate bending capacity of the sandwich wall panel in this application.

[0040] The ultimate bending bearing capacity of the sandwich panel is M u :

[0041]

[0042] Among them, f u is the longitudinal tensile strength of the grid plate 4;

[0043] A f is the total cross-sectional area of ​​the longitudinal limbs of the grid plate 4;

[0044] h0 is the effective height of the sandwich wall panel;

[0045] x is the relative compression zone height of the sandwich panel;

[0046] is the correction factor;

[0047] x1 is the wall thickness of the vertical end plate 51, the horizontal end plate 52 and the edge rib plate 53;

[0048] x2 is the cross-sectional length of the edge rib 53;

[0049] x3 is the cross-sectional length of the lateral end plate 52 .

[0050] according to Figure 3 As shown, the ordinate is the calculated value of the bending bearing capacity of the sandwich wall panel calculated in this application, and the abscissa is the simulated value of the bending bearing capacity of the sandwich wall panel. It can be seen that the calculated value of the bending bearing capacity of the present application is basically consistent with the simulated value.

[0051] The nonlinear finite element software ABAQUS was used to establish the numerical model of the sandwich wall panel in this application. The ultra-high performance concrete was established using a three-dimensional solid model, and the grid was established using a three-dimensional truss unit. The thickness of the concrete inner blade 1 and the concrete outer blade 3 is 30mm, the length is 2400mm, and the width is 1000mm. The cross-sectional area of ​​the horizontal and vertical limbs of the two sets of grid plates is 20mm 2 The overall thickness of the sandwich wall panel is 150 mm, and the spacing between two adjacent tie tubes 5 in the insulation board 2 is 600 mm. The grid plate 4 is a basalt fiber composite grid with a tensile strength of 1400 MPa, and the compressive strength of the concrete inner blade 1 and the concrete outer blade 3 is 120 MPa.

[0052] Under the above working conditions, the wall thickness x1 of the vertical end plate 51, the horizontal end plate 52 and the edge rib plate 53 is taken to be 6 mm or 8 mm; the cross-sectional length x2 of the edge rib plate 53 is taken to be 15 mm, 20 mm or 25 mm; the cross-sectional length x3 of the horizontal end plate 52 is taken to be 35 mm, 40 mm and 45 mm. There are 18 working conditions for the combination of the above parameters. The numerical simulation and analysis results corresponding to each working condition are shown in Table 1 below.

[0053] Table 1

[0054] serial number <![CDATA[x1]]> <![CDATA[x2]]> <![CDATA[x3]]> <![CDATA[M test ]]> <![CDATA[M u ]]> <![CDATA[M u / M test ]]> 6-15-35 6 15 35 24.06 24.49 1.017 6-15-40 6 15 40 23.12 23.43 1.013 6-15-45 6 15 45 22.23 22.37 1.007 6-20-35 6 20 35 23.71 23.78 1.003 6-20-40 6 20 40 22.79 22.73 0.997 6-20-45 6 20 45 21.91 21.67 0.989 6-25-35 6 25 35 23.21 23.08 0.994 6-25-40 6 25 40 22.31 22.02 0.987 6-25-45 6 25 45 21.51 20.97 0.975 8-15-35 8 15 35 27.87 27.86 1.000 8-15-40 8 15 40 26.71 26.81 1.004 8-15-45 8 15 45 26.19 25.75 0.983 8-20-35 8 20 35 27.49 27.16 0.988 8-20-40 8 20 40 26.34 26.10 0.991 8-20-45 8 20 45 25.83 25.05 0.970 8-25-35 8 25 35 26.74 26.46 0.989 8-25-40 8 25 40 25.68 25.40 0.989 8-25-45 8 25 45 22.56 24.34 1.079

[0055] In Table 1, M test is the ultimate bending bearing capacity of the wall panel obtained through software simulation analysis (unit: kN*m); M u is the ultimate bending bearing capacity of the wall panel calculated using the ultimate bending bearing capacity formula of this application; uand M test It can be seen from the ratio that the error between the ultimate bending bearing capacity of the wall panel calculated by this application and the simulation result is extremely low.

[0056] like Figure 2 It can be seen from the figure that under the bending state, the height gradient of the deformation of the sandwich wall panel of the present invention is relatively continuous, the layering is clear, the wall panel is reasonably stressed, has good collaborative working ability, and has excellent overall performance.

[0057] The basic principles of the present application are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present application are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present application. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, not for limitation, and the above details do not limit the present application to being implemented by adopting the above specific details.

[0058] The block diagrams of the devices, apparatuses, equipment, and systems involved in this application are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagram. As will be appreciated by those skilled in the art, these devices, apparatuses, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, referring to "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The words "such as" used here refer to the phrase "such as but not limited to", and can be used interchangeably with them.

Claims

1. An assembled concrete sandwich wall panel and a method for calculating the bending bearing capacity, characterized in that: The invention comprises a concrete inner blade plate (1), an insulation plate (2) and a concrete outer blade plate (3) which are stacked in sequence from bottom to top; a mesh plate (4) which is arranged parallel to the plate surface of the insulation plate (2) is pre-buried in the concrete outer blade plate (3) and the concrete inner blade plate (1); a tie tube (5) is arranged in the insulation plate (2) along the plate length direction; the tie tube (5) comprises two groups of vertical end plates (51) arranged in parallel and two groups of horizontal end plates (52) arranged in parallel; the vertical end plates (51) and the horizontal end plates (52) are enclosed to form a square tube-type cavity structure; edge ribs (53) are arranged on the plate surfaces of the two horizontal end plates (52); the insulation plate (2) is tied to the concrete outer blade plate (3) and the concrete inner blade plate (1) through the edge ribs (53) on the tie tube (5).

2. The assembled concrete sandwich wall panel and the method for calculating the bending bearing capacity according to claim 1 are characterized in that: The mesh plate (4) comprises transverse limbs and longitudinal limbs arranged in a cross-staggered manner, and the edge ribs (53) are arranged along the symmetry line direction of the transverse end plate (52) and are connected to one of the longitudinal limbs of the mesh plate (4).

3. The assembled concrete sandwich wall panel and the method for calculating the bending bearing capacity according to claim 1 or 2, characterized in that: The tie tubes (5) are evenly spaced in the horizontal direction inside the insulation board (2), and the spacing between adjacent tie tubes (5) is S, 500mm≤S≤700mm.

4. The assembled concrete sandwich wall panel and the method for calculating the bending bearing capacity according to claim 1 or 2, characterized in that: The wall thickness of the vertical end plate (51), the horizontal end plate (52) and the edge rib plate (53) is D, 5mm≤D≤10mm.

5. The assembled concrete sandwich wall panel and the method for calculating the bending bearing capacity according to claim 1 or 2, characterized in that: The thickness of the concrete inner blade plate (1) and the concrete outer blade plate (3) is H, 30 mm ≤ H ≤ 50 mm.

6. The assembled concrete sandwich wall panel and the method for calculating the bending bearing capacity according to claim 1 or 2, characterized in that: The insulation board (2) is made of extruded polystyrene.

7. The assembled concrete sandwich wall panel and the method for calculating the bending bearing capacity according to claim 1 or 2, characterized in that: The tensile strength of the grid plate (4) is 1400 MPa, and the compressive strength of the concrete outer blade plate (3) and the concrete inner blade plate (1) is 120 MPa.

8. A method for calculating the bending bearing capacity of an assembled concrete sandwich wall panel, characterized in that: The ultimate bending bearing capacity of the assembled concrete sandwich wall panel as claimed in claim 1 or 2 is M u : Among them, f u is the longitudinal tensile strength of the grid plate (4); A f is the total cross-sectional area of ​​the longitudinal limbs of the grid plate (4); h0 is the effective height of the sandwich wall panel; x is the relative compression zone height of the sandwich panel; is the correction factor; x1 is the wall thickness of the vertical end plate (51), the horizontal end plate (52) and the edge rib plate (53); x2 is the cross-sectional length of the edge rib (53); x3 is the cross-sectional length of the transverse end plate (52).

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