Non-dismantling formwork and composite floor slab manufactured by same

Abstract

The utility model discloses a dismantling-free formwork and a composite floor slab made of the dismantling-free formwork, the dismantling-free formwork is mainly composed of a prefabricated base plate, the prefabricated base plate is a concrete plate / or a cement plate / or a calcium silicate plate with fibers distributed inside, a plurality of connecting grooves and a plurality of nicks are machined on the upper surface of the prefabricated base plate, and the connecting grooves are connected with the nicks. And a plurality of fibers extend out of each nick. The composite floor slab comprises the non-dismantling formwork and a cast-in-place concrete layer poured on the non-dismantling formwork, a reinforcing mesh is arranged in the cast-in-place concrete layer, the connecting grooves and the nicks are filled with part of concrete at the bottom of the cast-in-place concrete layer, and the fiber filaments extending out of the base plate are condensed in the cast-in-place concrete layer along with pouring of the concrete. According to the non-dismantling formwork, it can be guaranteed that the laminated surfaces are stably connected, reinforcing steel bars / reinforcing steel bar trusses are omitted, and reliable connection between the non-dismantling formwork and a cast-in-place concrete layer is achieved through the non-dismantling formwork on the condition that the non-dismantling formwork is not connected with the cast-in-place concrete layer through the reinforcing steel bars.

Description

Technical Field

[0001] The utility model relates to the technical field of assembled building profiles, in particular to a disassembly-free formwork, and also to a composite floor slab formed by using the disassembly-free formwork. Background Art

[0002] Prefabricated concrete structure is one of the main structural forms promoted in the development of modern building industrialization, and composite floor is an important part of prefabricated concrete structure. Composite floor consists of prefabricated bottom plate and cast-in-place concrete layer, which combines the advantages of cast-in-place floor and fully prefabricated floor, and has the following advantages:

[0003] (1) Compared with fully prefabricated slabs, its overall stiffness and seismic performance are better. Compared with cast-in-place slabs, its construction speed is faster and more conducive to industrial production.

[0004] (2) The prefabricated base plate of the composite slab is manufactured in the factory, with a high degree of mechanization and a fast production line, so the quality of the components is guaranteed and it is not affected by seasonality;

[0005] (3) The templates used in the production of prefabricated base plates of composite panels in the factory can be reused. After being transported to the construction site for assembly, the prefabricated base plates of composite panels are used as templates for cast-in-place concrete. They are integrated with the cast-in-place concrete layer and do not need to be removed as non-dismantling templates, which greatly reduces the workload of dismantling templates and reduces on-site wet operations. This not only improves the on-site working environment, but also improves construction efficiency and significantly shortens the construction period.

[0006] (4) Reduce construction waste at the construction site and effectively control pollution to the surrounding environment.

[0007] In the prior art, composite floors are mainly divided into the following types according to different structural forms:

[0008] A. Steel truss concrete composite floor

[0009] The reinforced truss concrete composite floor is made by making steel bars into steel trusses, and pouring the lower half of the steel trusses together with concrete to form a prefabricated floor of the composite slab (no need to remove the formwork). During construction, the prefabricated floor of the composite slab is hoisted to the designated position of the design, and concrete is poured on the composite layer to form a reinforced truss concrete composite floor. The reinforced truss concrete composite floor is the most commonly used composite floor in the existing technology.

[0010] B. PK prestressed concrete composite floor

[0011] PK prestressed concrete composite floor slab is to make the prefabricated base plate of the composite board (non-dismantling formwork) into an inverted "T"-shaped prefabricated ribbed thin plate. The prestressed tendons use spiral ribs to eliminate stress of high-strength steel wire, and multiple holes are reserved on the ribs. During construction, the prefabricated base plate of the composite board is first laid flat, and then transverse perforated steel bars are inserted into the holes on the ribs, and short zigzag or parallel bars that meet the anchorage length requirements are arranged at the joints of the non-dismantling formwork, and then concrete is poured to form the PK prestressed concrete composite floor slab.

[0012] C. Ordinary rough surface prestressed concrete composite floor

[0013] Ordinary rough surface prestressed concrete composite floor slab is that prestressed steel bars are arranged in the precast base plate of the composite slab (no need to remove the formwork), and the superimposed surface between it and the cast-in-place concrete layer is set to a rough surface. During construction, the precast base plate of the composite slab is hoisted into place, negative bending moment steel bars are arranged at the dismantling seat, and then concrete is poured on the laid precast base plate of the composite slab to form a composite floor slab.

[0014] D. Steel truss floor deck

[0015] The steel truss floor deck is made by processing the steel bars into steel trusses in the factory, and welding the steel trusses to galvanized steel plates or mechanically connecting the steel trusses to fiber cement boards as a non-disassembly formwork, which is then transported to the construction site, laid directly on the beams, and after simple reinforcement work, concrete can be poured on it to form a steel truss floor deck.

[0016] E. Corrugated steel plate-concrete composite floor

[0017] The corrugated steel plate - concrete composite floor slab utilizes alternating concave and convex corrugated thin steel plates as prefabricated bottom plates and also as formwork, i.e., formwork that does not need to be dismantled. Reinforcement bars are arranged in the cast-in-place layer, which are then poured together with concrete and supported on steel beams to form the corrugated steel plate - concrete composite floor slab.

[0018] F. SPD composite prestressed concrete hollow slab

[0019] SPD composite prestressed concrete hollow slab is a slab that is subjected to joint stress by pouring a fine stone concrete composite layer on the rough surface of the prestressed concrete hollow slab, i.e., the top surface of the SP slab, which is formed by a process. The composite layer is bonded to the SP slab to form a whole.

[0020] The disadvantages of the above composite floor are:

[0021] ⑴ The prefabricated base plate (no need to remove formwork) of the above-mentioned A and B composite floor slabs needs to be connected to the cast-in-place concrete layer through structures such as steel bars. In the actual construction process, there are many construction processes, complex node structures, and a high degree of refinement in the installation of components. This requires more stringent requirements on the construction quality management of the construction unit.

[0022] (2) The reinforcement of the prefabricated bottom plate (without dismantling the formwork) in the composite floor will seriously interfere with the binding of the steel bars of the cast-in-place concrete layer and the side beams, and make it difficult to install the pre-buried wire pipes in the cast-in-place concrete layer. The pipeline layout of the composite floor as described in B above can only be arranged according to the rib holes. In most cases, it cannot take a short route, which will cause a waste of pipeline resources; and in the process of vibration and compaction, it cannot be guaranteed that the concrete with rib holes will be completely dense.

[0023] ⑶ The steel bar content is higher than that of traditional cast-in-place slabs. The non-dismantling formwork of the above-mentioned C and D composite slabs requires a large amount of steel plates / steel bars.

[0024] ⑷ The thickness of the composite floor is relatively large due to structural limitations. For example, when the load is small and the span is small, the cast-in-place floor can be as thick as 80mm, while the above-mentioned reinforced truss concrete composite floor needs to be more than 130mm thick, which not only wastes raw materials but also affects the floor height. Due to the above reasons, composite floors are currently difficult to promote. Utility Model Content

[0025] The first object of the utility model is to provide a non-disassembly formwork which can ensure that the overlapping surface has a stable connection and does not require steel bars / steel bar trusses.

[0026] The second object of the utility model is to provide a composite floor slab formed by the above-mentioned non-disassembly formwork, wherein the composite floor slab utilizes the above-mentioned non-disassembly formwork to achieve a reliable connection between the non-disassembly formwork and the cast-in-place concrete layer without the need for connecting the non-disassembly formwork to the cast-in-place concrete layer through steel bars.

[0027] The first object of the utility model is achieved by the following technical solutions:

[0028] A disassembly-free formwork, mainly composed of a prefabricated base plate, characterized in that: the prefabricated base plate is a concrete plate / cement plate / calcium silicate plate with fibers distributed inside, the upper surface of the prefabricated base plate is processed with a plurality of connecting grooves and a plurality of notches, and a plurality of fiber filaments extend out of each notch.

[0029] The connection grooves, notches and fiber threads on the non-disassembly formwork of the utility model are all used to connect with the cast-in-place concrete layer, so that the non-disassembly formwork can be connected with the cast-in-place concrete layer to form a stable whole.

[0030] The connection grooves of the utility model can be processed by conventional machining, and the notches can be formed by roughening with a strong high-pressure water gun (water jet) so that fiber filaments can be retained therein. Since the prefabricated substrate itself has fibers inside, during the roughening process of the water gun (water jet), the fibers are generally not cut off under the impact of high-pressure water, so that the fibers are exposed from the scouring surface and the fiber filaments are retained in the notches.

[0031] In the formed connection grooves and notches, the depth of the connection grooves is deeper than the notches, wherein the notches are preferably distributed densely on the upper surface of the substrate.

[0032] Preferably, the connection groove is a dovetail groove, the width of the notch of which is smaller than the width of the bottom thereof. The dovetail groove can make the connection between the non-disassembly formwork and the cast-in-place concrete layer more stable.

[0033] Preferably, the prefabricated substrate may be an ultra-high performance concrete board, or a fiber concrete board, or a calcium silicate board, or a fiber cement pressure board, or a ceramsite concrete board.

[0034] Generally speaking, ultra-high performance concrete boards, fiber concrete boards, calcium silicate boards, and fiber cement pressure boards all contain fibers, while expanded clay concrete boards can have fibers added during the preparation process.

[0035] Furthermore, the non-disassembly template is provided with a plurality of through holes, which are pre-formed holes to facilitate the later fixing and installation of fixing nails, because the non-disassembly template has a high strength and a high density, and it is difficult to open holes in the later stage.

[0036] Furthermore, the removal-free formwork also includes a bonding layer laid on the lower surface of the prefabricated base plate.

[0037] The bonding layer can be a polymer cement mortar layer, which is a mixture of cement, sand, admixtures, polymers and additives. On the one hand, it can enhance the adhesion of subsequent plastering materials, and on the other hand, it can work together with the fiber mesh cloth to strengthen and further serve as a barrier to the penetration of chloride ions into the substrate.

[0038] Furthermore, a fiber mesh cloth or a steel wire mesh is provided in the bonding layer, or a fiber mesh cloth or a steel wire mesh is provided between the bonding layer and the substrate. The fiber mesh cloth or the steel wire mesh increases the flexural strength and toughness of the non-disassembly formwork, and can reduce the cracking of the non-disassembly formwork during nailing in the later stage.

[0039] Furthermore, a sealing layer is provided on the lower surface of the substrate, and the sealing layer may be an epoxy resin coating, which may further serve as a barrier to the penetration of chloride ions into the substrate.

[0040] Preferably, an interface adhesive layer is respectively provided on the upper surface and / or four side surfaces of the non-disassembly template.

[0041] Preferably, the connecting grooves and notches are parallel, the depth of the notches is 0.1 to 3 mm, the width is 0.1 to 3 mm, and the spacing between adjacent notches is less than or equal to 15 mm; the depth of the connecting grooves is 4 to 15 mm, the width is 3 to 30 mm, and the spacing between adjacent connecting grooves is less than or equal to 200 mm; the thickness of the disassembly-free template is 8 to 35 mm, and the compressive strength of the substrate is greater than or equal to 25 MPa.

[0042] In addition, the free-to-remove template of this embodiment can also have the following improvements:

[0043] The four sides of the non-disassembly template are all chamfered.

[0044] The fiber mesh cloth in the bonding layer may be an alkali-resistant glass fiber mesh cloth or a carbon fiber mesh cloth.

[0045] The second invention objective of the utility model is achieved through the following technical solutions:

[0046] A composite floor slab comprises a non-disassembly formwork and a cast-in-place concrete layer poured on the non-disassembly formwork, wherein a steel mesh is arranged in the cast-in-place concrete layer, and is characterized in that: the non-disassembly formwork adopts the above-mentioned non-disassembly formwork which is processed with connecting grooves and notches on the upper surface of the prefabricated base plate and each notch has a plurality of fiber filaments extending therefrom, wherein the connecting grooves and notches are filled with part of the concrete at the bottom of the cast-in-place concrete layer, and the fiber filaments extending therefrom are condensed in the cast-in-place concrete layer as the concrete is poured.

[0047] At the construction site, after the non-disassembly formwork is built, the cast-in-place concrete layer is poured on the non-disassembly formwork. The non-disassembly formwork and the cast-in-place concrete layer of the utility model are reliably connected through connection grooves, notches and fiber wires without steel bars, and the non-disassembly formwork and the cast-in-place concrete layer form a floor slab that bears force together.

[0048] Preferably, the steel mesh is formed by welding transverse and longitudinal steel bars. The steel mesh may include an upper stress-bearing steel mesh and a lower stress-bearing steel mesh. When the non-dismantling formwork is used as a formwork for pouring a cast-in-place concrete layer, the lower stress-bearing steel mesh may not be provided. This is because the lower stress-bearing steel mesh will interfere with the steel bar binding on both sides of the beam, and will increase the thickness of the non-dismantling formwork (the thinnest requires 15+15+6=36mm).

[0049] Preferably, both the upper surface and the lower surface of the composite floor are provided with a finishing layer.

[0050] During construction, water and electricity pipes are pre-buried in the cast-in-place concrete layer.

[0051] Compared with the prior art, the utility model has the following beneficial effects:

[0052] (1) The process is simple, the node structure is simple, and the degree of refinement required is low:

[0053] The non-disassembly formwork of the utility model is formed as an integral unit, and no steel bars are required therein. The non-disassembly formwork and the cast-in-place concrete layer are stably and reliably connected via connecting grooves, notches and fiber filaments. The process is simple and the connecting steel bars are reduced. The reduction in steel bars makes the node structure of the composite floor slab simpler, which also reduces the requirements for the degree of refinement.

[0054] (2) The plate thickness can be made smaller:

[0055] The utility model no longer has a steel bar truss, and a stable connection is achieved through connection grooves, notches and fiber filaments, so the plate thickness can be made smaller.

[0056] Because the minimum height of the general steel truss is 65mm, the minimum thickness of the floor slab with steel truss is 95mm, and the minimum thickness of the truss reinforced concrete composite slab is 130mm. However, the present invention does not have the minimum thickness constraint, the thickness of the template-free part is the thickness of the steel protective layer, the overall thickness of the composite slab is consistent with the cast-in-place concrete slab, and the minimum thickness can reach 80mm.

[0057] (3) It will not interfere with the binding of the slab surface reinforcement and the slab side beam reinforcement in the later stage, making it easier to install the embedded wire pipe in the later stage:

[0058] The later steel bars and pre-buried wire pipes are installed in the cast-in-place concrete layer, but the utility model no longer sets steel bar trusses, and no steel bars are used to connect the non-dismantling formwork and the cast-in-place concrete layer, so there is no interference with the later steel bars and pre-buried wire pipes, making the installation of the later steel bars and pre-buried wire pipes easier;

[0059] (4) In practice, the thickness of the non-disassembly formwork of the present invention is generally consistent with the thickness of the protective layer required for the steel bars in the composite floor slab. During construction, the steel bars at the bottom of the cast-in-place concrete layer can be directly placed on the non-disassembly formwork, and the non-disassembly formwork of the present invention is further used as a protective layer for the bottom steel bars, thereby ensuring the thickness of the protective layer of the bottom steel bars, and preventing the phenomenon of insufficient or excessive thickness of the protective layer of the bottom steel bars. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 It is a three-dimensional schematic diagram of the non-disassembly template of the first embodiment of the utility model;

[0061] Figure 2 It is a cross-sectional schematic diagram of the non-disassembly template of the first embodiment of the utility model;

[0062] Figure 3 It is a three-dimensional schematic diagram of a composite floor slab according to the first embodiment of the utility model;

[0063] Figure 4 It is a cross-sectional schematic diagram of the composite floor slab of the first embodiment of the utility model;

[0064] Figure 5 It is one of the load-slip curves during the shear slip performance test of the non-dismantling formwork and the cast-in-place concrete layer;

[0065] Figure 6 This is the second load-slip curve diagram of the shear slip performance test of the non-dismantling formwork and the cast-in-place concrete layer;

[0066] Figure 7 It is a schematic diagram of the assembly structure of the test piece during the shear slip performance test of the non-disassembly formwork and the cast-in-place concrete layer;

[0067] Figure 8 It is a schematic diagram of the dimensions, sampling positions and numbers during the out-of-plane tensile bond strength test between the non-dismantling formwork and the cast-in-place concrete layer;

[0068] Fig. 9 It is a cross-sectional schematic diagram of the connection groove of the non-disassembly template of the second embodiment of the utility model;

[0069] Fig.10 It is a schematic cross-sectional view of the bottom of the non-disassembly template of the third embodiment of the utility model.

[0070] Meaning of reference numerals in the figure:

[0071] 1-prefabricated base plate; 11-connecting groove; 12-notch; 13-fiber filament; 14-through hole; 2-bonding layer; 3-fiber mesh cloth; 4-sealing layer; 5-cast-in-place concrete layer; 6-steel mesh; 61-upper stress-bearing steel mesh; 62-lower stress-bearing steel mesh. DETAILED DESCRIPTION

[0072] The utility model is further described below in conjunction with embodiments.

[0073] In the description of the present invention, it should be understood that descriptions involving orientation, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention 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 the present invention.

[0074] In the description of the present utility model, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood to exclude the number itself, and "above", "below", "within" etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0075] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0076] Embodiment 1:

[0077] like Figure 1 and Figure 2 The illustrated embodiment is a non-disassembly formwork of the first embodiment, which is mainly composed of a prefabricated substrate 1, which is a concrete board / cement board / calcium silicate board with fibers uniformly distributed inside.

[0078] The concrete board can be an ultra-high performance concrete board, a fiber concrete board, or a ceramsite concrete board; the cement board can be a fiber cement pressure board. Generally speaking, ultra-high performance concrete boards, fiber concrete boards, calcium silicate boards, and fiber cement pressure boards all contain fibers, and ceramsite concrete boards can have fibers added during the preparation process.

[0079] The upper surface of the prefabricated substrate 1 is processed with a plurality of connection grooves 11 and a plurality of notches 12 , and a plurality of fiber filaments 13 extend out of each notch 12 .

[0080] The connection groove 11 of this embodiment is a rectangular groove, the width of the upper notch is equal to the width of the bottom, and its processing is relatively simple. The connection grooves 11 are arranged in parallel, the depth of the connection grooves 11 is 4 to 15 mm, the width is 3 to 30 mm, and the spacing between adjacent connection grooves is less than or equal to 200 mm. The notches 12 are also arranged in parallel, the depth of the notches 12 is 0.1 to 3 mm, the width is 0.1 to 3 mm, and the spacing between adjacent notches 12 is less than or equal to 15 mm. The density of the notches 12 will be much greater than the density of the connection grooves 11, and the preferred distribution of the notches 12 is densely distributed on the upper surface of the substrate.

[0081] In this embodiment, a bonding layer 2 is laid on the lower surface of the prefabricated base plate 1. The bonding layer 2 is a polymer cement mortar layer. A fiber mesh cloth 3 or a steel mesh is arranged in the bonding layer 2. The fiber mesh cloth 3 is an alkali-resistant glass fiber mesh cloth or a carbon fiber mesh cloth.

[0082] In this embodiment, a sealing layer 4 is further provided on the lower surface of the prefabricated substrate 1 , and the sealing layer 4 is an epoxy resin coating.

[0083] The thickness of the non-disassembly template of this embodiment is 8 to 35 mm, and the compressive strength of the prefabricated substrate 1 is greater than or equal to 25 MPa. The upper surface and / or four side surfaces of the non-disassembly template are respectively provided with an interface adhesive layer. Chamfers are provided on all four sides of the non-disassembly template. A plurality of through holes 14 are provided on the non-disassembly template to facilitate the later fixing and installation of fixing nails.

[0084] like Figure 3 and Figure 4 The composite floor slab of the present embodiment is shown, which includes a non-disassembly formwork and a cast-in-place concrete layer 5. The non-disassembly formwork adopts the above-mentioned non-disassembly formwork with connection grooves and notches processed on the upper surface of the prefabricated base plate and each notch has many fiber filaments extending out of it, and the cast-in-place concrete layer 5 is cast on the prefabricated base plate 1 of the non-disassembly formwork at the construction site.

[0085] A steel mesh 6 is provided in the cast-in-place concrete layer 5, and part of the concrete at the bottom of the cast-in-place concrete layer 5 is filled with the connecting groove 11 and the notch 12. The fiber filaments 13 extending from the prefabricated base plate 1 are solidified in the cast-in-place concrete layer 5 as the concrete is poured, thereby connecting the non-disassembly formwork to the cast-in-place concrete layer 5 through the connecting groove 11, the notch 12 and the fiber filaments 13 extending from the base plate.

[0086] The steel mesh 6 of this embodiment is formed by welding transverse and longitudinal steel bars. The steel mesh 6 includes an upper stress-bearing steel mesh 61 and a lower stress-bearing steel mesh 62. The upper and lower surfaces of the composite floor are both provided with a finishing layer. During construction, water and electric pipes are pre-buried in the cast-in-place concrete layer 5.

[0087] In order to further verify the strength of the composite floor composed of the non-disassembly formwork and the cast-in-place concrete layer of the utility model, we conducted a series of tests. The following is the process of the shear slip performance test of the non-disassembly formwork and the cast-in-place concrete layer and the tensile bond strength test between the non-disassembly formwork and the cast-in-place concrete layer:

[0088] 1. Shear slip performance test of non-removal formwork and cast-in-place concrete layer

[0089] The shear-slip performance of the non-removal formwork and the cast-in-place concrete layer is determined by a double shear test, such as Figure 7 As shown, each double shear specimen includes two concrete test blocks with dimensions of 120mm×120mm×300mm; two tensile steel bars with a diameter of 18 and a length of 380mm; and two non-removable formworks with dimensions of 120mm×240mm.

[0090] The double shear test uses a mold connected to the steel bar to apply tension to the concrete test block to achieve indirect loading. Before loading, the upper and lower ends of the concrete test block are clamped by a clamp, and the dial indicator is placed between the two concrete blocks; at the beginning of loading, the lower clamp is fixed and the upper clamp moves upward, so that the entire component is subjected to a tensile load; as the load increases, the non-removal formwork and the concrete test block produce relative displacement, achieving a pure shear state of the interface during loading. The test uses displacement control for loading, and the loading rate of the testing machine is 1.0mm / min. The specimens of the non-removal formwork are divided into 4 groups according to the longitudinal, transverse, and roughening of the material.

[0091] The shear slip performance of the non-dismantling formwork and concrete is defined by the average shear stress τ of the double shear specimen. The average shear stress is calculated according to formula (1-1):

[0092]

[0093] Where: τ——average shear stress of double shear specimen (MPa);

[0094] Fmax——test limit tensile force (N);

[0095] A——Test piece bonding surface area (mm 2 ).

[0096] The test data of the double shear specimens after removing the specimen with the largest error are listed in Table 1 below:

[0097] Table 1

[0098]

[0099]

[0100] The load-slip curves of each specimen are shown in Figure 5 and Figure 6 shown.

[0101] From Table 1 and Figure 5 , 6 It can be seen that the average shear stress of the non-removal formwork specimens with roughening of the longitudinal grooves is the largest, and its failure phenomenon is concrete tensile shear failure. The board and concrete have not yet debonded at the time of failure, that is, the shear slip performance between the non-removal formwork and concrete with roughening of the longitudinal grooves is the best. The non-removal formwork specimens without roughening of the longitudinal grooves not only have a large slip volume, but also have a detachment failure mode, and have poor performance.

[0102] For the transverse groove specimens, the transverse groove structure increases the mechanical bite force between the non-removal formwork and concrete, thereby improving the bonding performance between the non-removal formwork and concrete. At the same time, since the transverse tensile strength of the non-removal formwork is lower than the longitudinal tensile strength in the material performance test, its failure mode is that the non-removal formwork is pulled apart regardless of whether it is roughened or not. The roughened structure of the non-removal formwork with transverse grooves is perpendicular to the force direction, which weakens the cross section and further reduces the effective thickness of the non-removal formwork, thereby bringing the tearing failure of the non-removal formwork forward.

[0103] 2. Tensile bond strength test between non-removal formwork and cast-in-place concrete layer

[0104] In order to test the bonding performance between the non-removal formwork and concrete at different ages, a tensile bond strength test was carried out on the bonding performance between the non-removal formwork and the cast-in-place concrete layer with reference to the "Test Methods for Building Adhesives (Part 1: Test Methods for Ceramic Tile Adhesives)" (GB / T 12954.1-2008).

[0105] Since the non-removal formwork-concrete composite slab is cast as the formwork at the bottom during actual construction, in order to accurately measure the actual bonding strength, the non-removal formwork used in the test component is also placed at the bottom for casting. Six days after casting, the component is demoulded and turned over so that the non-removal formwork is located on the top surface. Then, a cutting machine is used to cut 50mm×50mm in size at a certain interval on the non-removal formwork, which is used to paste the standard size 50mm×50mm pulling head. After an interval of 24 hours, a pulling test machine is used to test. The cutting depth is greater than 20mm to ensure that the non-removal formwork is completely cut.

[0106] There are two parameters studied in this test, namely the grooved roughened area and the roughened area without grooves, and the bonding performance of the three parameters at the ages of 7d, 14d, and 28d was tested respectively. In order to reduce accidental errors, 4 samples of each parameter were taken from two different plates, for a total of 8 samples.

[0107] The calculation rules for the average tensile bond strength of the specimens under various parameters are as follows:

[0108] The tensile bond strength of a single specimen is calculated according to the following formula, accurate to 0.1 MPa.

[0109]

[0110] Where:

[0111] S 拉 ——Tensile bond strength of a single specimen, in megapascals (MPa);

[0112] F 拉 ——Tension, in Newton (N);

[0113] A——bonding area, in square millimeters (mm 2 ).

[0114] The tensile bond strength at different ages and under different parameters is determined by the following provisions:

[0115] 1. Calculate the arithmetic mean of the 8 test pieces;

[0116] 2. Discard data that are outside the range of the arithmetic mean ± 20%;

[0117] 3. If there are still five or more data left, find the new arithmetic mean;

[0118] 4. If less than five data are retained, retest;

[0119] 5. Determine the failure mode of each specimen.

[0120] The size of the non-removable formwork used for pouring, the sampling location and number are as follows: Figure 8As shown. When making the pull-out test piece, double-layer steel bars are required to avoid cracking when turning over, and the sampling position must avoid the steel bar position. Among them, the thickness of the composite plate used for the pull-out test is 100mm.

[0121] The L series represents the roughened surface without grooves, and the C series represents the roughened surface with grooves. Taking L2-1 as an example, L2 represents the second specimen of the roughened surface without grooves, and -1 represents the first board of the repeated test.

[0122] The specimens were cast in C30 commercial concrete, and the measured standard values ​​of the cubic compressive strength at 7d, 14d, and 28d are listed in Table 2 below:

[0123] Table 2

[0124]

[0125] The pull-out test uses the SJ-10 facing tile bond strength tester.

[0126] There are four basic failure phenomena of tensile bonded specimens, including: (1) concrete breakage: the failure surface is located in the post-cast concrete; (2) interface failure: failure at the bonding interface between the non-dismantling formwork and the post-cast concrete; (3) non-dismantling formwork breakage: the failure surface occurs inside the non-dismantling formwork material; (4) adhesive pull-off failure: adhesive pull-off failure between the pulling head and the non-dismantling formwork. In addition, there are combinations of the above failure phenomena, mainly (2) interface failure + (3) non-dismantling formwork breakage, (3) non-dismantling formwork breakage + (4) adhesive pull-off failure.

[0127] Among them, the actual bonding area (A) is measured and calculated according to the size of the cut-out template after the pull-out test. The measurement is carried out with a vernier caliper, accurate to 0.1mm. The changes in the tensile bonding specimens of the three surface treatment methods over the days are summarized in Table 3, and the detailed data are listed in Tables 4 to 9.

[0128] According to the data after treatment, the 7-day tensile bond strength of the non-removal formwork has reached 75% of that of 28 days, and the tensile bond strength at the non-grooved part is slightly higher. Overall, the 28-day tensile bond strength (1.94×2 / 12+2.17×10 / 12=2.13MPa) has exceeded the standard value of the axial tensile strength of C30 concrete of 2.01MPa.

[0129] Table 3

[0130]

[0131] Table 4

[0132]

[0133] Table 5

[0134]

[0135] Table 6

[0136]

[0137] Table 7

[0138]

[0139] Table 8

[0140]

[0141] Table 9

[0142]

[0143]

[0144] Embodiment 2:

[0145] like Figure 5 As shown, the non-disassembly template of the second embodiment is different from that of the first embodiment in the connection groove 11. The connection groove 11 of the second embodiment is a dovetail groove, and the width of the groove is smaller than the width of the bottom.

[0146] Embodiment three:

[0147] like Figure 6 As shown, the non-disassembly template of the third embodiment is different from that of the first embodiment in that a fiber mesh cloth 3 or a steel mesh is arranged between the bonding layer 2 and the substrate 1 in this embodiment.

[0148] The above-mentioned embodiments of the utility model are not intended to limit the protection scope of the utility model, and the implementation methods of the utility model are not limited to these. All other various forms of modifications, replacements or changes made to the above-mentioned structure of the utility model based on the above-mentioned contents of the utility model, in accordance with the common technical knowledge and customary means in the field, without departing from the above-mentioned basic technical ideas of the utility model, should fall within the protection scope of the utility model.

Claims

1. A non-disassembly template, mainly composed of a prefabricated substrate, characterized in that: The prefabricated substrate is a concrete board / cement board / calcium silicate board with fibers distributed inside. The upper surface of the prefabricated substrate is processed with a plurality of connection grooves and a plurality of notches, and a plurality of fiber filaments extend out of each notch.

2. The non-disassembly template according to claim 1 is characterized in that: The connecting groove is a dovetail groove, and the width of the groove opening is smaller than the width of the bottom.

3. The non-disassembly template according to claim 1 is characterized in that: The substrate is an ultra-high performance concrete board, or a fiber concrete board, or a calcium silicate board, or a fiber cement pressure board, or a ceramsite concrete board.

4. The non-disassembly template according to claim 1 is characterized in that: The non-disassembly template is provided with a plurality of through holes.

5. The non-disassembly template according to claim 1 is characterized in that: The non-disassembly template also includes a bonding layer laid on the lower surface of the prefabricated substrate.

6. The non-disassembly template according to claim 5 is characterized in that: A fiber mesh cloth or a steel wire mesh is arranged in the bonding layer, or a fiber mesh cloth or a steel wire mesh is arranged between the bonding layer and the substrate.

7. The non-disassembly template according to claim 5 is characterized in that: A sealing layer is provided on the lower surface of the substrate, and the sealing layer is an epoxy resin coating.

8. The non-disassembly template according to claim 1 is characterized in that: The upper surface and / or four side surfaces of the non-disassembly template are respectively provided with an interface adhesive layer.

9. The non-disassembly template according to claim 1 is characterized in that: The connection grooves and notches are arranged in parallel, the depth of the notches is 0.1 to 3 mm, the width is 0.1 to 3 mm, and the spacing between adjacent notches is less than or equal to 15 mm; the depth of the connection grooves is 4 to 15 mm, the width is 3 to 30 mm, and the spacing between adjacent connection grooves is less than or equal to 200 mm; the thickness of the disassembly-free template is 8 to 35 mm, and the compressive strength of the substrate is greater than or equal to 25 MPa.

10. A composite floor slab, comprising a non-removable formwork and a cast-in-place concrete layer cast on the non-removable formwork, wherein a steel mesh is provided in the cast-in-place concrete layer, characterized in that: The non-disassembly formwork adopts the non-disassembly formwork described in any one of claims 1 to 9, part of the concrete at the bottom of the cast-in-place concrete layer fills the connecting grooves and notches, and the fiber filaments extending from the prefabricated base plate are condensed in the cast-in-place concrete layer as the concrete is poured.

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