CN108412049A - A kind of wood-concrete combination beam shear connector push out test test specimen - Google Patents

Abstract

The present invention is a push-out test specimen of a wood-concrete composite beam shear connector, including a wooden beam, a concrete slab, a shear connector, an anchor and a steel mesh, and the shear connector is anchored to the wooden beam through the anchor In the upper part, the upper part of the wooden beam is laid with a reinforcement mesh through the supporting formwork, and the transverse reinforcement in the reinforcement mesh passes through the perforation reserved on the shear connector, so that the reinforcement mesh and the shear connector The concrete slabs are poured into the formwork parts for the skeleton, forming a wood-concrete composite beam. The invention improves the shear strength and shear stiffness of the shear connector, has good fatigue resistance, reduces the shear deformation of the connector, and further reduces the overall deformation of the wood-concrete composite beam, and is effective in resisting relative slippage At the same time, it can effectively suppress the lifting effect between the concrete slab and the wooden beam, and has good social benefits and transformation prospects.

Description

Push-out test specimen of a wood-concrete composite beam shear connector

technical field

The invention relates to the technical field of new structures of civil engineering, in particular to a push-out test specimen of a wood-concrete composite beam shear connector.

Background technique

my country has abundant forest resources, but engineering timber that can be used for load-bearing parts is still relatively small, mainly relying on foreign imports. Therefore, at present, the construction cost of modern wooden structure buildings made of pure wood in my country is often relatively high. Combining wood with other building materials is a good choice, which can not only give full play to the advantages of each material, but also effectively reduce the cost of the project. Wood-concrete composite structure is one of the typical representatives.

At present, the shear connectors of wood-concrete composite beams mainly include wood screws, planting bars, perforated metal plates, pin+groove combined connections, and PBL connectors. However, the research results show that most of the above-mentioned shear connectors are flexible connectors. Although the shear deformation capacity is good, their shear bearing capacity and stiffness are limited, so that the combination efficiency between wood and concrete is not high; The production and construction process of connectors with high shear bearing capacity and rigidity is relatively cumbersome, and some of them are easy to cause concrete splitting damage.

Contents of the invention

The purpose of the present invention is to overcome the problems existing in the prior art, and provide a shear connector push-out test specimen, which can be used in the field of wood-concrete composite structures and bridges, including the reinforcement and transformation of existing wood-concrete structures.

In order to achieve the above-mentioned technical purpose and achieve the above-mentioned technical effect, the present invention is realized through the following technical solutions:

A wood-concrete composite beam shear connector push-out test specimen, including a wooden beam, a concrete slab, a shear connector, an anchor and a steel mesh, the shear connector is anchored on the upper part of the wooden beam through the anchor, and the The upper part of the wooden beam is laid with a reinforcement mesh through the supporting formwork, and the transverse reinforcement in the reinforcement mesh passes through the perforation reserved on the shear connector, and the reinforcement mesh and the shear connector are used as the skeleton. The concrete slab is poured into the template to form a wood-concrete composite beam.

Further, the shear connector includes at least a web and a bottom plate, the web and the bottom plate are preset with perforations, and the perforations on the web are matched with the transverse steel bars in the reinforcement mesh, and the bottom plate The perforation on the anchor fits through the anchorage.

Further, the shear connector is H-shaped steel, T-shaped steel, angle steel, channel steel, bent steel plate or FRP I-shaped bar.

Further, the anchors are wood screws, self-tapping screws or planting bars.

Further, the concrete used for the concrete slab is one or more of ordinary concrete, recycled concrete, lightweight concrete, self-compacting concrete or fiber-reinforced concrete.

Further, the cross section of the wooden beam is rectangular, square or I-shaped.

Further, the material of the wooden beam is log, laminated glulam, rotary-cut glulam, parallel wood-chip glulam or laminated wood-chip glulam.

Further, the steel bars used in the steel mesh are smooth round steel bars, threaded steel bars or fiber-reinforced plastic bars.

A construction method for pushing out a test specimen of a wood-concrete composite beam shear connector, the construction method comprising the following steps:

Step 1) pre-perforate the web and bottom plate of the shear connector;

Step 2) According to the design requirements, pre-drill holes where the shear connectors are arranged at the corresponding positions of the wooden beams;

Step 3) For anchors using planted bars, the bar planting operation needs to be performed first, and the planted bars are implanted into the interior of the wooden beam;

Step 4) Anchor the shear connector to the upper part of the wooden beam through wood screws, self-tapping screws or planting bars;

Step 5) Support the formwork parts on both sides of the wooden beam, and make the upper surface of the formwork part flush with the upper surface of the wooden beam;

Step 6) Lay reinforcement mesh in the formwork, and the transverse reinforcement at the collision position with the shear connector passes through the reserved perforation on the web of the shear connector;

Step 7) Concrete is finally poured to form the concrete slab.

The beneficial effects of the present invention are:

1. Adopting the shear connector of the present invention further improves the shear strength and shear stiffness of the shear connector, thereby improving the combination efficiency between wood and concrete. At the same time, the shear connector provided by the present invention belongs to Rigid connectors with good fatigue resistance.

2. Compared with the traditional flexible shear connectors, the present invention reduces the shear deformation of the connectors, further reduces the overall deformation of the wood-concrete composite beam, improves the combination efficiency, and has more superior structural performance. In addition, the shear connector provided by the present invention is a rigid shear connector, which can effectively suppress the lifting effect between the concrete slab and the wooden beam while resisting relative slippage, so that the two can cooperate well Work.

3. The present invention provides a new idea for the design of connectors, expands the application range of combined structures, and has good social benefits and transformation prospects.

Description of drawings

Fig. 1 adopts the front elevation view of the push-out test specimen of the bent steel plate shear connector provided by the present invention;

Fig. 2 is the side elevation view of the push-out test specimen using the bent steel plate shear connector provided by the present invention;

Fig. 3 adopts the front elevation view of the push-out test specimen of the double angle steel shear connector provided by the present invention;

Fig. 4 adopts the side elevation view of the push-out test specimen of the double angle steel shear connector provided by the present invention;

Fig. 5 adopts the front elevation view of the push-out test specimen of the double channel steel shear connector provided by the present invention;

Fig. 6 is the side elevation view of the push-out test specimen of the double channel steel shear connector provided by the present invention;

Fig. 7 is the front elevation view of the push-out test specimen using the perforated inverted T-shaped steel shear connector provided by the present invention;

Fig. 8 is the side elevation view of the push-out test specimen of the perforated inverted T-shaped steel shear connector provided by the present invention;

Fig. 9 is the front elevation view of the push-out test specimen using the I-shaped cross-section shear connector provided by the present invention;

Fig. 10 is a side elevation view of a push-out test specimen using the I-shaped cross-section shear connector provided by the present invention.

Explanation of symbols in the figure: 1. shear connector, 2. anchor, 3. concrete slab, 4. wooden beam, 5. steel mesh.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

As shown in Fig. 1 to Fig. 10, a kind of wood-concrete composite beam shear connector pushes out test specimen, comprises wooden beam 4, concrete slab 3, shear connector 1, anchor 2 and steel mesh 5, described The shear connector 1 is anchored on the upper part of the wooden beam 4 through the anchor 2, and the upper part of the wooden beam 4 is laid with a steel mesh 5 through the formwork part supported, and the transverse reinforcement in the steel mesh 5 passes through the shear connection The reserved perforation on the part 1 is poured with the concrete slab 3 in the template part with the steel mesh 5 and the shear connector 1 as the skeleton to form a wood-concrete composite beam.

The shear connector 1 at least includes a web and a bottom plate, the web and the bottom plate are preset with perforations, and the perforations on the web are matched with the transverse steel bars in the reinforcement mesh 5, and the bottom plate The perforation is matched with the anchor piece 2 for piercing and anchoring.

The shear connector 1 is H-shaped steel, T-shaped steel, angle steel, channel steel, bent steel plate or FRP I-shaped bar.

The anchors 2 are wood screws, self-tapping screws or planting bars.

The concrete used for the concrete slab 3 is one or more of ordinary concrete, recycled concrete, lightweight concrete, self-compacting concrete or fiber reinforced concrete.

The cross section of the wooden beam 4 is rectangular, square or I-shaped.

The material of the wooden beam 4 is logs, laminated glulam, rotary-cut glulam, parallel wood-chip glulam or laminated wood-chip glulam.

The steel bars adopted in the steel bar mesh 5 are smooth round steel bars, threaded steel bars or fiber-reinforced plastic bars.

A construction method for pushing out a test specimen of a wood-concrete composite beam shear connector, the construction method comprising the following steps:

Step 1) Pre-perforate the web and bottom plate of the shear connector 1;

Step 2) According to the design requirements, pre-drilling is carried out at the position where the shear connector 1 is arranged at the corresponding position of the wooden beam 4;

Step 3) For the anchor piece 2 using the planting bar, the bar planting operation needs to be performed first, and the planting bar is implanted into the interior of the wooden beam 4;

Step 4) Anchoring the shear connector 1 to the upper part of the wooden beam 4 through wood screws, self-tapping screws or planting bars;

Step 5) supporting formwork parts on both sides of the wooden beam 4, and making the upper surface of the formwork part flush with the upper surface of the wooden beam 4;

Step 6) Lay reinforcement mesh 5 in the formwork, and the transverse reinforcement at the collision position with the shear connector 1 passes through the reserved perforation on the web of the shear connector 1;

Step 7) Concrete is finally poured to form the concrete slab 3, and then cured. After curing, the formwork is removed, and finally a wood-concrete composite beam with a new type of shear connector is pushed out as a test specimen.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (9)

1. A wood-concrete composite beam shear connector push-out test specimen, characterized in that it includes a wooden beam (4), a concrete slab (3), a shear connector (1), an anchor (2) and a steel bar net (5), the shear connector (1) is anchored to the upper part of the wooden beam (4) through the anchor (2), and the upper part of the wooden beam (4) is laid with a steel mesh (5) , the transverse reinforcement in the reinforcement mesh (5) passes through the perforation reserved on the shear connector (1), and the template part is formed with the reinforcement mesh (5) and the shear connector (1) as the skeleton The concrete slab (3) is poured inside to form a wood-concrete composite beam. 2. The wood-concrete composite beam shear connector push-out test specimen according to claim 1, characterized in that, the shear connector (1) at least includes a web and a bottom plate, and the web and the bottom plate Perforations are preset on the top, and the perforations on the web are connected and matched with the transverse steel bars in the reinforcement mesh (5), and the perforations on the bottom plate are connected and anchored with the anchor piece (2). 3. The wood-concrete composite beam shear connector push-out test specimen according to claim 2, characterized in that, the shear connector (1) is H-shaped steel, T-shaped steel, angle steel, channel steel, bent Steel plate or FRP I-shaped profile. 4. The push-out test specimen of wood-concrete composite beam shear connector according to claim 2, characterized in that, the anchor (2) is a wood screw, a self-tapping screw or a planted bar. 5. The push-out test specimen of wood-concrete composite beam shear connector according to claim 1, characterized in that, the concrete used in the concrete slab (3) is ordinary concrete, recycled concrete, lightweight concrete, self-compacting concrete Or one or more of fiber reinforced concrete. 6. The push-out test specimen of wood-concrete composite beam shear connector according to claim 1, characterized in that, the section form of the wood beam (4) is rectangular, square or I-shaped. 7. The push-out test specimen of wood-concrete composite beam shear connector according to claim 6, characterized in that, the material of the wooden beam (4) is log, plywood, rotary cut board glued wood, parallel Chip glulam or laminated glulam. 8. The push-out test specimen of wood-concrete composite beam shear connectors according to claim 1 or 2, characterized in that the steel bars used in the steel mesh (5) are smooth round steel bars, threaded steel bars or fiber reinforced Plastic bars. 9. A kind of construction method that wood-concrete composite beam shear connector pushes out test piece, it is characterized in that, this construction method comprises the steps: Step 1) pre-perforating the web and bottom plate of the shear connector (1); Step 2) According to the design requirements, pre-drill holes at the corresponding positions where the shear connectors (1) are arranged on the wooden beams (4); Step 3) For the anchor piece (2) using rebar, it is necessary to perform the rebar planting operation first, and implant the rebar into the interior of the wooden beam (4); Step 4) Anchoring the shear connector (1) to the upper part of the wooden beam (4) by means of wood screws, self-tapping screws or planting bars; Step 5) Support the formwork parts on both sides of the wooden beam (4), and make the upper surface of the formwork part flush with the upper surface of the wooden beam (4); Step 6) Lay reinforcement mesh (5) in the formwork, and the transverse reinforcement at the collision position with the shear connector (1) passes through the reserved perforation on the web of the shear connector (1); Step 7) Concrete is finally poured to form the concrete slab (3).