Beam type test piece for testing bonding performance of built-in steel bar-recombined bamboo

Abstract

The utility model discloses a beam type test piece for testing the bonding performance of built-in steel bar-recombined bamboo. The beam type test piece comprises a connecting piece I and a connecting piece II which are hinged with each other, and the connecting piece I and the connecting piece II are respectively fixed with a recombined bamboo beam I and a recombined bamboo beam II which are arranged in the same direction; a first steel bar is arranged in the first recombined bamboo beam, and a second steel bar is arranged in the second recombined bamboo beam. One ends of part of the steel bars I in the plurality of steel bars I are positioned outside the recombined bamboo beam I, and one ends of part of the steel bars II in the plurality of steel bars II are positioned outside the recombined bamboo beam II; and the steel bar I outside the recombined bamboo beam I is fixedly connected with the steel bar II outside the recombined bamboo beam II. In the process of testing the bonding performance of the built-in reinforcing steel bar-recombined bamboo, the first recombined bamboo beam and the second recombined bamboo beam can rotate mutually and limit the relative horizontal displacement of the first recombined bamboo beam and the second recombined bamboo beam when being pressed, the stress conditions of the first reinforcing steel bar and the second reinforcing steel bar bonded in the recombined bamboo can be reflected to the maximum extent under the load effect, and the stress conditions accord with the actual component stress.

Description

TECHNICAL FIELD

[0001] The utility model relates to the bamboo structure field in civil engineering, more specifically, it relates to a beam type test piece for testing the bonding performance of built-in steel bars-reconstituted bamboo. BACKGROUND

[0002] Under the background of developing green and environmentally-friendly ecological buildings, bamboo building materials and modern bamboo structure buildings have natural advantages and great potential. Compared with the traditional building materials commonly used at present, bamboo has the advantages of short growth cycle, high strength-weight ratio, lightweight and earthquake resistance, and natural degradation after abandonment, and can be called natural green building materials.

[0003] Reconstituted bamboo is a new type of green bamboo engineering material made of original bamboo as the main raw material and through processes such as splitting, bamboo chip defibration, drying, glue dipping, paving and hot pressing. Reconstituted bamboo is light in weight and high in strength, and can form a combined component with different materials, has low energy consumption and high industrialization degree. However, the cross-sectional stiffness of the reconstituted bamboo component is small, the elastic modulus is low, and the ductility is also poor. Therefore, one of the existing methods is to embed steel bars in the reconstituted bamboo component, and the combination of the two as a structural component can fully utilize the strength of reconstituted bamboo and steel, enhance the ductility of the component, and increase the design span. At the same time, the steel bars are pre-embedded in the bamboo bundle by hot pressing during the processing of reconstituted bamboo, which is integrally formed without the need for secondary drilling, grooving and anchoring, avoids weakening the cross section of the component, and is beneficial to improving the overall stiffness, bearing capacity and ductility performance of the component.

[0004] For the above-mentioned composite component of steel bars and reconstituted bamboo, good bonding and anchoring performance between reconstituted bamboo and embedded steel bars is the prerequisite for the cooperative work of the two, and is also an important guarantee for the reliable structural performance of the built-in steel bar-reconstituted bamboo beam.

[0005] At present, the bonding performance between steel bars and concrete has been well studied. Studies have shown that there are many factors affecting the bonding performance, and the actual bonding stress state is complex, which makes the bonding performance test results not strong in applicability. The commonly used bonding test method is the center tension test. Although this method brings convenience to the loading conditions and the preparation of test specimens, due to the great difference in the actual stress form of various structural components, there is local extrusion force at the loading end when the load is applied, which will affect the reliability of the test results.

[0006] Therefore, it is necessary to provide a beam type test piece for testing the bonding performance of built-in steel bars-reconstituted bamboo, which can overcome the above problems. UTILITY MODEL CONTENTS

[0007] Therefore, the utility model provides a beam type test piece for testing the bonding performance of built-in steel bars-reconstituted bamboo.

[0008] In order to achieve the above-mentioned purpose, the utility model adopts the following technical solutions:

[0009] A beam type test piece for built-in steel bar-reconstituted bamboo bonding performance test comprises a connecting piece one, a connecting piece two, a reconstituted bamboo beam one and a reconstituted bamboo beam two, the connecting piece one and the connecting piece two are hinged and both have a hinge axis, the connecting piece one and the connecting piece two are respectively detachably fixed with the reconstituted bamboo beam one and the reconstituted bamboo beam two, the hinge axis is arranged between the reconstituted bamboo beam one and the reconstituted bamboo beam two, the length direction of the reconstituted bamboo beam one is perpendicular to the hinge axis, and the center line in the length direction of the reconstituted bamboo beam one is collinear with the center line in the length direction of the reconstituted bamboo beam two; a plurality of steel bars one with the same length direction as the reconstituted bamboo beam one are arranged in the reconstituted bamboo beam one, and a plurality of steel bars two with the same length direction as the reconstituted bamboo beam two are arranged in the reconstituted bamboo beam two; the plurality of steel bars one and the plurality of steel bars two are respectively located opposite to each other along the length direction of the reconstituted bamboo beam one; one end of part of the steel bars one in the plurality of steel bars one is located outside the reconstituted bamboo beam one, and one end of part of the steel bars two in the plurality of steel bars two is located outside the reconstituted bamboo beam two; the end of the steel bar one located outside the reconstituted bamboo beam one is correspondingly fixed with the end of the steel bar two located outside the reconstituted bamboo beam two; the center line in the length direction of the reconstituted bamboo beam one is located between the hinge axis and the end of the steel bar one located outside the reconstituted bamboo beam one.

[0010] Compared with the prior art, the beam type test piece for built-in steel bar-reconstituted bamboo bonding performance test has the advantages that the reconstituted bamboo beam one and the reconstituted bamboo beam two are hinged through the connecting piece one and the connecting piece two, the steel bar one is arranged in the reconstituted bamboo beam one, the steel bar two is arranged in the reconstituted bamboo beam two, and part of the steel bar one in the reconstituted bamboo beam one is connected with part of the steel bar two in the reconstituted bamboo beam two; when the built-in steel bar-reconstituted bamboo bonding performance is tested, the tensile region of the beam type test piece is the steel bar one and the steel bar two to be tested, and the compression region is arranged with the connecting piece one and the connecting piece two hinged together; the above design enables the reconstituted bamboo beam one and the reconstituted bamboo beam two to rotate and limit the relative horizontal displacement when compressed, and under the action of load, the stress conditions of the steel bar one and the steel bar two bonded in the reconstituted bamboo can be reflected to the maximum extent, which is consistent with the actual component stress, the force arm is simple and the force transmission is clear, and the bonding state of the steel bar in the reconstituted bamboo under the action of bending moment and shear force can be accurately simulated.

[0011] Preferably, the cross-sectional shape of the first and second reconstituted bamboo beams is rectangular, the long and wide side walls of the first reconstituted bamboo beam are aligned with the long and wide side walls of the second reconstituted bamboo beam, two rows of the first reinforcing bars are fixed in the first reconstituted bamboo beam along the length direction of the cross section of the first reconstituted bamboo beam, each row of the first reinforcing bars is provided with a plurality of the first reinforcing bars, the first reinforcing bars in the same row are arranged equidistantly along the width direction of the cross section of the first reconstituted bamboo beam, the width direction of the cross section of the first reconstituted bamboo beam is parallel to the axis of the hinge shaft, and the center line of the first reconstituted bamboo beam in the length direction is located between the two rows of the first reinforcing bars. When the first and second reconstituted bamboo beams are compressed, the tensile region of the beam specimen is ensured to be the first and second reinforcing bars to be tested.

[0012] Preferably, the first connecting piece comprises a rectangular plate, a mounting plate and a hinge piece, one end of the first reconstituted bamboo beam is provided with a rectangular slot penetrating through one wide side wall and two long side walls of the first reconstituted bamboo beam, the end of one row of the first reinforcing bars in the first reconstituted bamboo beam is flush with the slot side wall of the rectangular slot, the rectangular plate is tightly embedded in the rectangular slot, two ends of the rectangular plate are each vertically fixed with one mounting plate, the plate faces of the two mounting plates are each tightly attached to the two long side walls of the first reconstituted bamboo beam, the mounting plate is provided with a through hole, one end of a screw is fixed on the first reconstituted bamboo beam after penetrating through the through hole, the hinge piece is fixed with the rectangular plate, the rectangular plate is located between the hinge piece and the mounting plate, the hinge piece is provided with a hinge hole, the second connecting piece comprises a rectangular plate, a mounting plate and a hinge piece, one end of the second reconstituted bamboo beam is provided with a rectangular slot penetrating through one wide side wall and two long side walls of the second reconstituted bamboo beam, the end of one row of the second reinforcing bars in the second reconstituted bamboo beam is flush with the slot side wall of the rectangular slot, the rectangular plate is tightly embedded in the rectangular slot, two ends of the rectangular plate are each vertically fixed with one mounting plate, the plate faces of the two mounting plates are each tightly attached to the two long side walls of the second reconstituted bamboo beam, the mounting plate is provided with a through hole, one end of a screw is fixed on the second reconstituted bamboo beam after penetrating through the through hole, the hinge piece is fixed with the rectangular plate, the rectangular plate is located between the hinge piece and the mounting plate, the hinge piece is provided with a hinge hole, the hinge hole of the first connecting piece is coaxially arranged with the hinge hole of the second connecting piece, and a connecting shaft is simultaneously inserted into the hinge hole of the first connecting piece and the hinge hole of the second connecting piece. The first connecting piece can be quickly and reliably fixed on the first reconstituted bamboo beam, the second connecting piece can be quickly and reliably fixed on the second reconstituted bamboo beam, and the first connecting piece and the second connecting piece can be reliably hinged.

[0013] Preferably, one side plate surface of the rectangular plate one is flush with the end wall of the re-bamboo beam one provided with the rectangular groove one; one side plate surface of the rectangular plate two is flush with the end wall of the re-bamboo beam two provided with the rectangular groove two. When the re-bamboo beam one and the re-bamboo beam two are arranged horizontally and under compression, the design is conducive to the load being accurately transmitted by the connecting piece one and the connecting piece two. BRIEF DESCRIPTION OF DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only the embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of the provided drawings.

[0015] Figure 1 is a whole axonometric view of a beam specimen for testing the bonding performance of a built-in steel bar-re-bamboo;

[0016] Figure 2 is a local axonometric view of a beam specimen for testing the bonding performance of a built-in steel bar-re-bamboo Figure One ;

[0017] Figure 3 is a local axonometric view of a beam specimen for testing the bonding performance of a built-in steel bar-re-bamboo Figure Two ;

[0018] Figure 4 is a schematic diagram of the arrangement of a beam specimen for testing the bonding performance of a built-in steel bar-re-bamboo on a loading device Figure One ;

[0019] Figure 5 is a schematic diagram of the arrangement of a beam specimen for testing the bonding performance of a built-in steel bar-re-bamboo on a loading device Figure Two ;

[0020] Figure 6 is a test load-displacement curve of the beam specimen A and the beam specimen B;

[0021] Figure 7 is a flowchart of a preparation method of a beam specimen for testing the bonding performance of a built-in steel bar-re-bamboo.

[0022] In the drawings:

[0023] 1 is a rectangular plate one, 2 is a mounting plate one, 3 is a hinged piece one, 4 is a rectangular plate two, 5 is a mounting plate two, 6 is a hinged piece two, 7 is a re-bamboo beam one, 8 is a re-bamboo beam two, 9 is a steel bar one, 10 is a steel bar two, 11 is a screw one, 12 is a screw two, 13 is a connecting shaft, 14 is a loading device. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the utility model will be clearly and completely described below. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all the other embodiments obtained by the ordinary skilled in the art without creative labor fall within the protection scope of the utility model.

[0025] The utility model discloses a kind of beam test pieces for built-in steel bar-reconstituted bamboo bonding performance test, beam test piece in the utility model includes reconstituted bamboo beam one 7 and reconstituted bamboo beam two 8, reconstituted bamboo beam one 7 and reconstituted bamboo beam two 8 are hinged by connecting piece one and connecting piece two, reconstituted bamboo beam one 7 is equipped with steel bar one 9, reconstituted bamboo beam two 8 is equipped with steel bar two 10, part of reconstituted bamboo beam one 7 protruding steel bar one 9 and part of reconstituted bamboo beam two 8 protruding steel bar two 10 meet;When built-in steel bar-reconstituted bamboo bonding performance test is carried out, the tensile region of the beam test piece is steel bar one 9 and steel bar two 10 to be tested, and the compression region is arranged with connecting piece one and connecting piece two hinged together, the above design makes reconstituted bamboo beam one 7 and reconstituted bamboo beam two 8 can rotate each other when being compressed and can limit its relative horizontal displacement, can reflect the stress condition of steel bar one 9 and steel bar two 10 bonded in reconstituted bamboo to the greatest extent under load, consistent with actual component stress, arm of force is simple and force transmission is clear, can accurately simulate the bonding state of steel bar in reconstituted bamboo under bending moment and shear force;Connecting piece one and connecting piece two used in test can be reused, save cost;

[0026] Connecting piece one and connecting piece two are simple in structure and can be quickly and reliably fixed on reconstituted bamboo beam one 7 and reconstituted bamboo beam two 8 respectively, and in combination with the design of rectangular groove one and rectangular groove two, reconstituted bamboo beam one 7 and reconstituted bamboo beam two 8 are horizontally arranged and can accurately transmit load when being compressed, thereby improving the reliability of test results;

[0027] The beam test piece in the application is simple in structure and reasonable in design, and connecting piece one and connecting piece two of different sizes can be applied to reconstituted bamboo beams of different cross-sectional sizes.

[0028] The preparation method of the beam test piece is simple and reliable, and steel bar one 9 and steel bar two 10 can be reliably fixed in reconstituted bamboo beam one 7 and reconstituted bamboo beam two 8 respectively;Steel bar one 9 protruding from reconstituted bamboo beam one 7 and steel bar two 10 protruding from reconstituted bamboo beam two 8 can be quickly fixed by welding, connecting piece one and connecting piece two can be quickly and detachably fixed on reconstituted bamboo beam one 7 and reconstituted bamboo beam two 8 respectively, and connecting piece one and connecting piece two can be reused.

[0029] EMBODIMENT

[0030] Referring to the drawingsFigures 1-7 For the overall and partial structure schematic diagram of an embodiment of the utility model, the utility model discloses a kind of beam test pieces for built-in steel bar-reconstituted bamboo bonding performance test, which includes connecting piece one, connecting piece two, reconstituted bamboo beam one 7 and reconstituted bamboo beam two 8;

[0031] Connecting piece one and connecting piece two are hinged and have a hinge axis, and connecting piece one and connecting piece two are respectively detachably fixed with reconstituted bamboo beam one 7 and reconstituted bamboo beam two 8, the hinge axis is arranged between reconstituted bamboo beam one 7 and reconstituted bamboo beam two 8, and the length direction of reconstituted bamboo beam one 7 is perpendicular to the hinge axis.

[0032] The shape and size of reconstituted bamboo beam one 7 and reconstituted bamboo beam two 8 are completely the same, and the center line in the length direction of reconstituted bamboo beam one 7 is collinear with the center line in the length direction of reconstituted bamboo beam two 8; in the present application, the cross-sectional shape of reconstituted bamboo beam one 7 and reconstituted bamboo beam two 8 is rectangular, and the long side wall and the wide side wall of reconstituted bamboo beam one 7 are respectively aligned with the long side wall and the wide side wall of reconstituted bamboo beam two 8.

[0033] Reconstituted bamboo beam one 7 is internally provided with a plurality of steel bars one 9 in the same length direction, and reconstituted bamboo beam two 8 is internally provided with a plurality of steel bars two 10 in the same length direction; the plurality of steel bars one 9 and the plurality of steel bars two 10 are respectively located opposite in the length direction of reconstituted bamboo beam one 7.

[0034] One end of part of the plurality of steel bars one 9 is located outside reconstituted bamboo beam one 7, and the end of the steel bar one 9 located outside reconstituted bamboo beam one 7 is aligned; one end of part of the plurality of steel bars two 10 is located outside reconstituted bamboo beam two 8, and the end of the steel bar two 10 located outside reconstituted bamboo beam two 8 is aligned.

[0035] The end of the steel bar one 9 located outside reconstituted bamboo beam one 7 corresponds in position to the end of the steel bar two 10 located outside reconstituted bamboo beam two 8 and is fixedly connected, and the fixedly connecting mode is welding.

[0036] The center line in the length direction of reconstituted bamboo beam one 7 is located between the hinge axis and the end of the steel bar one 9 located outside reconstituted bamboo beam one 7.

[0037] For the arrangement of the steel bar one 9 in reconstituted bamboo beam one 7, specifically, two rows of steel bars one 9 are fixed in reconstituted bamboo beam one 7 in sequence along the length direction of the cross section thereof, each row of steel bars one 9 is provided with a plurality of steel bars one 9, the plurality of steel bars one 9 located in the same row are arranged in sequence at equal distances along the width direction of the cross section of reconstituted bamboo beam one 7, each row of steel bars one 9 is provided with two steel bars one 9 in the present embodiment, the width direction of the cross section of reconstituted bamboo beam one 7 is parallel to the hinge axis, and the center line in the length direction of reconstituted bamboo beam one 7 is located between the two rows of steel bars one 9; the arrangement form of the steel bar two 10 in reconstituted bamboo beam two 8 is the same as the arrangement form of the steel bar one 9 in reconstituted bamboo beam one 7.

[0038] Further specifically, the connecting piece one comprises a rectangular plate one 1, a mounting plate one 2 and a hinge piece one 3, one end of the reconstituted bamboo beam one 7 is provided with a rectangular groove one penetrating through one wide side wall and two long side walls, the end of the row of steel bars one 9 in the reconstituted bamboo beam one 7 is flush with the groove side wall of the rectangular groove one; the rectangular plate one 1 is closely embedded in the rectangular groove one, two ends of the rectangular plate one 1 are respectively vertically fixed with a rectangular mounting plate one 2, the plate faces of the two mounting plates one 2 are respectively close to the two long side walls of the reconstituted bamboo beam one 7, one or more circular through holes one are provided on the mounting plate one 2, one end of the screw one 11 is screwed on the reconstituted bamboo beam one 7 after penetrating through the through hole one, so as to realize the fixation of the mounting plate one 2 and the reconstituted bamboo beam one 7; one side plate face and one side wall of the rectangular plate one 1 are respectively close to one side groove wall and groove bottom wall of the rectangular groove one, the other side plate face of the rectangular plate one 1 is flush with the end wall of the reconstituted bamboo beam one 7 provided with the rectangular groove one; the hinge piece one 3 is fixed with the rectangular plate one 1, the hinge piece one 3 is arranged between the two mounting plates one 2, the rectangular plate one 1 is between the hinge piece one 3 and the mounting plate one 2, a circular hinge hole one is provided on the hinge piece one 3;

[0039] Further specifically, the connecting piece two comprises a rectangular plate two 4, a mounting plate two 5 and a hinge piece two 6, one end of the reconstituted bamboo beam two 8 is provided with a rectangular groove two penetrating through one wide side wall and two long side walls, the end of the row of steel bars two 10 in the reconstituted bamboo beam two 8 is flush with the groove side wall of the rectangular groove two; the rectangular plate two 4 is closely embedded in the rectangular groove two, two ends of the rectangular plate two 4 are respectively vertically fixed with a rectangular mounting plate two 5, the plate faces of the two mounting plates two 5 are respectively close to the two long side walls of the reconstituted bamboo beam two 8, one or more circular through holes two are provided on the mounting plate two 5, one end of the screw two 12 is screwed on the reconstituted bamboo beam two 8 after penetrating through the through hole two, so as to realize the fixation of the mounting plate one 2 and the reconstituted bamboo beam one 7; one side plate face and one side wall of the rectangular plate two 4 are respectively close to one side groove wall and groove bottom wall of the rectangular groove two, the other side plate face of the rectangular plate two 4 is flush with the end wall of the reconstituted bamboo beam two 8 provided with the rectangular groove two; the hinge piece two 6 is fixed with the rectangular plate two 4, the hinge piece two 6 is arranged between the two mounting plates two 5, the rectangular plate two 4 is between the hinge piece two 6 and the mounting plate two 5, a circular hinge hole two is provided on the hinge piece two 6; the hinge hole one and the hinge hole two are coaxially arranged, the connecting shaft 13 is simultaneously inserted into the hinge hole one and the hinge hole two.

[0040] A preparation method of a beam specimen for testing the bonding performance of built-in steel bars and reconstituted bamboo, comprising:

[0041] ①Preparation of the reconstituted bamboo beam one 7 and the reconstituted bamboo beam two 8:

[0042] Phyllostachys pubescens preparation stage: select Phyllostachys pubescens, cut into the required length, and then perform fiberization treatment after removing the node of the Phyllostachys pubescens to obtain Phyllostachys pubescens fibers;

[0043] Bamboo fiber treatment: bamboo fibers are heated and carbonized, then soaked in a glue pool for treatment, and finally dried and maintained to obtain a reconstituted bamboo bundle;

[0044] Preparation of reconstituted bamboo board: the reconstituted bamboo bundle is laid into a hot-pressing mold, and steel bars are arranged in the hot-pressing mold during laying according to design requirements, the parts of the steel bars extending out of the reconstituted bamboo bundle are tensioned and fixed by anchorage devices to ensure that the positions of the steel bars do not deviate during hot pressing, and the steel bars and the reconstituted bamboo bundle are laid to obtain a reconstituted bamboo board with steel bars after hot pressing;

[0045] Maintenance and treatment of reconstituted bamboo board: after the reconstituted bamboo board is pressed, it is maintained, and after the maintenance is completed, the anchorage devices on both sides are removed; the reconstituted bamboo board is cut and polished according to design requirements, and the surface of the cut reconstituted bamboo board is smooth and flat;

[0046] Gluing treatment: phenolic PUR glue is applied to the surface of the cut reconstituted bamboo board, and multiple reconstituted bamboo boards are bonded together, and a jack is used to apply pressure to the bonded reconstituted bamboo boards, and a reconstituted bamboo beam 7 or a reconstituted bamboo beam 8 is obtained after pressing, that is, the reconstituted bamboo beam 7 and the reconstituted bamboo beam 8 are pressed in the same way as described above.

[0047] ②Steel bar 9 and steel bar 10 are fixedly connected:

[0048] Firstly, the reconstituted bamboo beam 7 and the reconstituted bamboo beam 8 are adjusted so that the center line in the length direction of the reconstituted bamboo beam 7 is collinear with the center line in the length direction of the reconstituted bamboo beam 8;

[0049] Then, the end of the steel bar 9 outside the reconstituted bamboo beam 7 is fixedly connected with the end of the steel bar 10 outside the reconstituted bamboo beam 8 in position by welding;

[0050] ③Install connecting piece 1 and connecting piece 2:

[0051] Firstly, a rectangular slot 1 is formed at the end of the reconstituted bamboo beam 7, and a rectangular slot 2 is formed at the end of the reconstituted bamboo beam 8, and after the rectangular slot 1 and the rectangular slot 2 are formed, the ends of a row of steel bars 9 in the reconstituted bamboo beam 7 are flush with the slot side walls of the rectangular slot 1, and the ends of a row of steel bars 10 in the reconstituted bamboo beam 8 are flush with the slot side walls of the rectangular slot 2;

[0052] Then, the connecting shaft 13 is inserted into the hinge hole 1 and the hinge hole 2 at the same time;

[0053] Finally, the rectangular plate 1 is embedded in the rectangular slot 1, and the screw 11 is screwed on the reconstituted bamboo beam 7 after passing through the through hole 1; the rectangular plate 2 is embedded in the rectangular slot 2, and the screw 12 is screwed on the reconstituted bamboo beam 7 after passing through the through hole 2.

[0054] In this embodiment, the design parameters of the beam specimen for testing the bonding performance of the built-in steel bar-reconstituted bamboo are as follows: the length of the reconstituted bamboo beam one 7 and the reconstituted bamboo beam two 8 is 680 mm, the width is 100 mm, and the height is 150 mm; four HRB400 steel bars one 9 are arranged in the reconstituted bamboo beam one 7, and four HRB400 steel bars two 10 are arranged in the reconstituted bamboo beam two 8; the diameter of the steel bars one 9 and the steel bars two 10 is 20 mm; the shortest distance from the end of the steel bars one 9 outside the reconstituted bamboo beam one 7 to the reconstituted bamboo beam one 7 is 40 mm, and the shortest distance from the end of the steel bars two 10 outside the reconstituted bamboo beam two 8 to the reconstituted bamboo beam two 8 is 40 mm; the steel bars one 9 outside the reconstituted bamboo beam one 7 and the steel bars two 10 outside the reconstituted bamboo beam two 8 are quickly connected by butt welding; the groove depth of the rectangular groove one and the rectangular groove two is 50 mm, and the groove width is 20 mm; and the reconstituted bamboo beam one 7 and the reconstituted bamboo beam two 8 are connected through the connecting piece one and the connecting piece two.

[0055] During the test, the reconstituted bamboo beam one 7 and the reconstituted bamboo beam two 8 in the beam specimen are arranged horizontally, the hinge axis line is arranged horizontally, the steel bars one 9 and the steel bars two 10 welded together are located below the hinge axis line, and the upper surfaces of the reconstituted bamboo beam one 7 and the reconstituted bamboo beam two 8 are subjected to vertical downward pressure; the beam specimen adopts a four-point bending loading mode, and the bending moment at the center of the beam specimen is only borne by the connecting piece one, the connecting piece two, the steel bars one 9, and the steel bars two 10; the beam specimen is simply supported and bears two equal loads.

[0056] The bonding performance of the built-in steel bar-reconstituted bamboo is investigated by the four-point bending loading mode, and the arrangement of the beam specimen on the loading device 14 is shown in Figs. Figure 4 and Figure 5 The flexural bearing capacity and deformation of the following two working condition combination beams are compared.

[0057] Beam specimen A: the steel bars one 9 and the steel bars two 10 in the beam specimen A are both 2C16 type;

[0058] Beam specimen B: the steel bars one 9 and the steel bars two 10 in the beam specimen B are both 2C20 type;

[0059] Figure 6 The test load-displacement curves of the beam specimen A and the beam specimen B are shown in Fig., in which the horizontal axis is displacement, and the vertical axis is load. The deflection of the beam specimen A under the same load is reduced, which indicates that the flexural bearing capacity of the beam specimen A is significantly increased with the increase of the reinforcement ratio, the effect of improving the bending stiffness is obvious, and through the use of the connecting piece one and the connecting piece two, the stress state of the steel bars one 9 and the steel bars two 10 can be accurately reflected during the test, and the precision of the test results is improved.

[0060] The various embodiments described in this specification are presented for the purpose of illustration and description. Each of the embodiments highlights a different aspect of the disclosure, and the embodiments are presented separately for ease of understanding. The same or similar elements are common throughout the embodiments and are not repeated in the description.

[0061] The above description of disclosed embodiments is intended to be illustrative and not restrictive. Many modifications of these embodiments by one having ordinary skill in the art are intended to be within the scope of the disclosure. The general principles defined herein can be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the present disclosure is not to be limited to the embodiments described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed.

Claims

1. A beam specimen for testing the bond performance of embedded steel bars-reconstituted bamboo, characterized in that, The application relates to a hinge joint structure of a bamboo beam, which comprises a connecting piece one, a connecting piece two, a recombined bamboo beam one (7) and a recombined bamboo beam two (8), the connecting piece one and the connecting piece two are hingedly connected and have a hinge joint axis, the connecting piece one and the connecting piece two are respectively detachably fixed with the recombined bamboo beam one (7) and the recombined bamboo beam two (8), the hinge joint axis is arranged in the middle between the recombined bamboo beam one (7) and the recombined bamboo beam two (8), the length direction of the recombined bamboo beam one (7) is perpendicular to the hinge joint axis, and the center line in the length direction of the recombined bamboo beam one (7) is collinear with the center line in the length direction of the recombined bamboo beam two (8); a plurality of steel bars one (9) with the same length direction as the recombined bamboo beam one (7) are arranged in the recombined bamboo beam one (7), and a plurality of steel bars two (10) with the same length direction as the recombined bamboo beam two (8) are arranged in the recombined bamboo beam two (8); the plurality of steel bars one (9) and the plurality of steel bars two (10) are respectively located opposite to each other along the length direction of the recombined bamboo beam one (7); one end of part of the steel bars one (9) in the plurality of steel bars one (9) is located outside the recombined bamboo beam one (7), and one end of part of the steel bars two (10) in the plurality of steel bars two (10) is located outside the recombined bamboo beam two (8); the end of the steel bar one (9) located outside the recombined bamboo beam one (7) is correspondingly fixed with the end of the steel bar two (10) located outside the recombined bamboo beam two (8); and the center line in the length direction of the recombined bamboo beam one (7) is located between the hinge joint axis and the end of the steel bar one (9) located outside the recombined bamboo beam one (7).

2. The beam specimen for testing the bond performance between embedded steel bars and re-bamboo according to claim 1, characterized in that, The cross section of the recombined bamboo beam one (7) and the recombined bamboo beam two (8) is rectangular, the long side wall and the wide side wall of the recombined bamboo beam one (7) are respectively aligned with the long side wall and the wide side wall of the recombined bamboo beam two (8); two rows of the steel bars one (9) are fixed in the recombined bamboo beam one (7) along the length direction of the cross section of the recombined bamboo beam one (7) in sequence, each row of the steel bars one (9) is provided with a plurality of steel bars one (9), and the plurality of steel bars one (9) located in the same row are arranged in sequence and equidistantly along the width direction of the cross section of the recombined bamboo beam one (7); the width direction of the cross section of the recombined bamboo beam one (7) is parallel to the hinge joint axis; and the center line in the length direction of the recombined bamboo beam one (7) is located between the two rows of the steel bars one (9).

3. The beam specimen for testing the bond performance between embedded steel bars and re-bamboo according to claim 2, characterized in that, The connecting piece one comprises a rectangular plate one (1), a mounting plate one (2) and a hinge piece one (3), one end of the reconstituted bamboo beam one (7) is provided with a rectangular slot one penetrating one wide side wall and two long side walls, the end of one row of the reinforcing bars one (9) in the reconstituted bamboo beam one (7) is flush with the slot side wall of the rectangular slot one; the rectangular plate one (1) is tightly embedded in the rectangular slot one, two ends of the rectangular plate one (1) are each vertically fixed with one mounting plate one (2), the plate faces of the two mounting plate ones (2) are each closely attached to the two long side walls of the reconstituted bamboo beam one (7), the mounting plate one (2) is provided with a through hole one, one end of a screw one (11) is fixed on the reconstituted bamboo beam one (7) after penetrating the through hole one; the hinge piece one (3) is fixed with the rectangular plate one (1), the rectangular plate one (1) is located between the hinge piece one (3) and the mounting plate one (2), the hinge piece one (3) is provided with a hinge hole one; the connecting piece two comprises a rectangular plate two (4), a mounting plate two (5) and a hinge piece two (6), one end of the reconstituted bamboo beam two (8) is provided with a rectangular slot two penetrating one wide side wall and two long side walls, the end of one row of the reinforcing bars two (10) in the reconstituted bamboo beam two (8) is flush with the slot side wall of the rectangular slot two; the rectangular plate two (4) is tightly embedded in the rectangular slot two, two ends of the rectangular plate two (4) are each vertically fixed with one mounting plate two (5), the plate faces of the two mounting plate twos (5) are each closely attached to the two long side walls of the reconstituted bamboo beam two (8), the mounting plate two (5) is provided with a through hole two, one end of a screw two (12) is fixed on the reconstituted bamboo beam two (8) after penetrating the through hole two; the hinge piece two (6) is fixed with the rectangular plate two (4), the rectangular plate two (4) is located between the hinge piece two (6) and the mounting plate two (5), the hinge piece two (6) is provided with a hinge hole two; the hinge hole one and the hinge hole two are coaxially arranged, a connecting shaft (13) is simultaneously inserted into the hinge hole one and the hinge hole two.

4. The beam specimen for testing the bond performance between embedded steel bars and re-bamboo according to claim 3, characterized in that, One side plate face of the rectangular plate one (1) is flush with the end wall of the reconstituted bamboo beam one (7) provided with the rectangular slot one; one side plate face of the rectangular plate two (4) is flush with the end wall of the reconstituted bamboo beam two (8) provided with the rectangular slot two.

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