CN106049687A - Spatial sandwich joint for improving anti-seismic performance through casing pipes and construction method - Google Patents

Abstract

The invention discloses a space sandwich node and a construction method for improving the anti-seismic performance by adopting casings, and belongs to the technical field of structural engineering; the improved space sandwich node is composed of concrete in the core area of a beam-column slab, steel bars, and a casing in the core area. During the construction process, first complete the binding of steel bars, the longitudinal reinforcement of beams in the core area is placed in sleeves, the same type of low-grade concrete is used for beams, slabs and core areas when the formwork is poured, and high-grade concrete is used for columns. The pouring sequence is the lower column, the core area of the beam slab, and the upper column. The invention reduces the load transmitted to the core area from the beam longitudinal bar by applying PVC sleeves to the beam longitudinal bars at the core area of the node, reduces the shear and deformation of the core area, and improves the mechanical performance of the sandwich node. Since the casing weakens the effect of the beam, the concrete strength of the beam and slab can be appropriately increased during construction, so that the strength level difference between the beam and column meets the requirements of the code, improving its seismic performance, and making up for the deficiencies in traditional construction. It can be popularized for High-rise concrete structure building.

Description

Space Sandwich Joints and Construction Methods Using Casings to Improve Seismic Performance

technical field

The invention relates to a method and a construction process for improving the anti-seismic performance of joints by adopting casings. There are two types of casings: PVC casings and steel pipe casings, which belong to the technical field of structural engineering and are mainly used in construction projects.

Background technique

In multi-storey and high-rise structures, columns are limited by the axial compression ratio and cross-section, and beams are limited by cracks. At the same time, due to the cost and the requirements of strong columns and weak beams, the strength of column concrete is generally higher than that of beams and slabs. The design strength difference between the two will increase with the increase of building height, especially in the lower part of high-rise buildings. At present, the commonly used conventional construction method is to use the traditional joints poured with high-strength concrete of the same strength as the column in the core area, but this construction method is not ideal. Not only is the construction difficult, the construction quality is difficult to control, and it is difficult to achieve The floor is poured before the initial setting, resulting in a large number of construction joints, causing potential safety hazards. Another construction method is to use low-strength concrete sandwich joints with the same strength as the beams. This method is easy to construct, makes up for the shortcomings of traditional joints, and greatly shortens the construction period. However, when the beam-column level of the sandwich joint differs by more than two, it is not allowed to use lower-strength beam-slab concrete to pour the core area. For this reason, the author designs the method and construction technology of using bushings to improve the seismic performance of joints, so as to meet the needs of high-rise buildings.

Contents of the invention

The present invention proposes a method and a construction process for improving the seismic performance of joints by adopting sleeves, the purpose of which is to reduce the load introduced by beam longitudinal reinforcements by applying different sleeves to the beam longitudinal reinforcements at the core area of the joints, and further reduce the core area The shear and deformation of the sandwich joint improve its mechanical performance. Since the casing weakens the effect of the beam, the concrete strength of the beam and slab can be appropriately increased during construction, so that the strength level difference between the beam and column of this type of sandwich joint meets the specification requirements. It makes up for the deficiencies in the construction of traditional joints and general sandwich joints. The structure system is simple, safe and reliable, the construction method is simple and easy to construct, and the cost is low, so it has wide application prospects and can be popularized for high-rise concrete structure buildings.

In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is a space sandwich node that adopts sleeves to improve the seismic performance, and is characterized in that: the space sandwich node is composed of concrete beam (1), concrete column (2), concrete core area (3) , concrete slab (4), beam longitudinal reinforcement (5), beam stirrup (6), column longitudinal reinforcement (7), column stirrup (8), node stirrup (9), upper plate reinforcement (10), lower Rib (11) and casing (12) form.

Wherein, the connection arrangement of the above-mentioned components can refer to the accompanying drawings, the concrete columns (2) are vertically arranged, the concrete beams (1) are placed in the middle of the concrete columns (2) orthogonal to each other, and the concrete core area (3) is the concrete beam (1 ), the intersection structure between the concrete columns (2), the concrete slab (4) is located between the concrete beams (1) and the upper part is on the same plane as the upper part of the beam. The beam longitudinal bars (5) are set in two layers and run through the concrete beam (1), the column longitudinal bars (7) are evenly arranged longitudinally, and the beam stirrups (6) and column stirrups (8) are placed on the corresponding beam longitudinal bars (5). , The column longitudinal reinforcement (7) is bound evenly, the node stirrup (9) is evenly bound to the column longitudinal reinforcement (7) in the concrete core area (3), and the upper plate reinforcement (10) and the lower plate reinforcement (11) are in the concrete The plates (4) are arranged up and down and the steel bars are perpendicular to each other.

The concrete beam (1), the concrete core area (3), and the concrete slab (4) adopt low-type concrete.

Described concrete column (2) adopts the concrete of high model.

Described beam longitudinal reinforcement (5), column longitudinal reinforcement (7), node stirrup (9) adopt HRB400 steel bar, and described beam stirrup (6), column stirrup (8), upper plate reinforcement (10) And lower plate reinforcement (11) adopts HPB300 reinforcing bar.

The inner diameter of the casing (12) is larger than the longitudinal reinforcement of the beam and the length is equal to the column width. The inner diameter of the casing is not larger than the diameter of the longitudinal reinforcement of the beam by 6 mm, so as to prevent the concrete from flowing into the gap caused by the excessively wide gap between the casing and the longitudinal reinforcement Thereby affecting the insulation effect of the casing.

During the construction process, first complete the binding of steel bars, the longitudinal beams in the core area are placed in sleeves, the beams, slabs and core areas are made of the same low-grade concrete when the formwork is poured, and the columns are made of high-grade concrete. The pouring sequence is the lower column, the core area of the beam slab, and the upper column.

The construction method of the space sandwich joint that adopts the casing to improve the seismic performance includes the following steps:

Step 1: According to the construction drawings, cut the steel bars and prepare different types of concrete to be poured;

Step 2: Pre-process the longitudinal reinforcement and stirrup according to the attached drawing, and place the casing in the middle of the longitudinal reinforcement of the specified beam;

Step 3: Bind the steel bars. Use steel wires to complete the binding of the stirrups of the longitudinal reinforcement of the column. When binding the stirrups, proceed sequentially from bottom to top. Insert the longitudinal reinforcement of the beam from the core area, and arrange the upper and lower layers in two layers. Use steel wires to complete the binding of the beam stirrup and the longitudinal reinforcement of the beam. Note that the longitudinal reinforcement of the beam covered with a sleeve is in the middle of the inner layer;

Step 4: Complete the binding of steel bars and perform formwork pouring. When pouring, first pour the lower part of the column with the prepared high-type concrete, and after sufficient vibration, pour the beam slab and the core area with low-type concrete, continue to vibrate, smooth the concrete slab, continue to pour the upper column with high-type concrete, and vibrate again Pound evenly;

Step 5: Curing the test piece, after 28 days, it can be demolded and formed

The present invention is based on the design of traditional space traditional nodes and sandwich nodes and the improvement of construction and production. Compared with it, the advantages of the present invention are:

1. Compared with the traditional joints, the space sandwich joints with casing improvement measures reduce the construction difficulty, shorten the construction period and ensure the construction quality.

2. Compared with ordinary sandwich joints, casing improvement measures are adopted to block the bond between the steel bar and concrete in the core area, reduce the load introduced by the longitudinal reinforcement of the beam, further reduce the shear and deformation of the core area, and improve the strength of the sandwich joint. its stress performance.

3. Since the casing weakens the effect of the beam, the concrete strength of the beam and slab can be appropriately increased during construction, so that the strength grade difference between the beam and column of this type of sandwich node meets the specification requirements. It makes up for the deficiencies in the construction of traditional joints and general sandwich joints.

Description of drawings

Figure 1 is a schematic diagram of a space sandwich node with casing improvement measures.

Figure 2 is a schematic diagram of the concrete of the space sandwich node with casing improvement measures.

Fig. 3 is a schematic diagram of the reinforcement of the space sandwich node with casing improvement measures.

Fig. 4 is a schematic diagram of connecting nodes.

Figure 5 is a plan view of beam-column reinforcement for sandwich joints.

Fig. 6 is a cross-sectional view of a column.

Figure 7 is a cross-sectional view of the beam.

Figure 8 Sectional view of the beam section in the core area.

Figure 9 is the reinforcement plane of the lower slab of the sandwich joint.

Figure 10 is the reinforcement plane of the slab on the sandwich joint.

Figure 11 is a schematic diagram of a sandwich node.

Figure 12 is the effect diagram of the casing of the beam reinforcement in the core area of the sandwich joint.

Figure 13 is a detailed view of the casing.

Fig. 14 is a detailed view of the longitudinal section of the casing-reinforcement bar.

Figure 15 is a detailed view of the casing-bar cross-section.

Figure 16 is a schematic diagram of column stirrups.

Figure 17 is a schematic diagram of beam stirrups.

In the figure: 1-concrete beam, 2-concrete column, 3-concrete core area, 4-concrete slab, 5-beam longitudinal reinforcement, 6-beam stirrup, 7-column longitudinal reinforcement, 8-column stirrup, 9- Node stirrups, 10-upper reinforcement, 11-lower reinforcement, 12 sleeves.

detailed description

Describe the best embodiment of the present invention in detail below in conjunction with technical scheme and accompanying drawing:

The method and construction technology of improving the aseismic performance of joints with casings are adopted. The construction and production are as follows. In the specific implementation, first, the beam longitudinal reinforcement (5) and beam hoops are prepared according to the component size of the space sandwich nodes of the casing improvement measures actually required. Steel bars (6), column longitudinal bars (7), column stirrups (8), node stirrups (9), upper plate bars (10), lower plate bars (11), and concrete beams (1), concrete columns (2), concrete core area (3), concrete slab (4) and other concrete.

According to the accompanying drawings 16 and 17 of beam stirrups (6), column stirrups (8) and node stirrups (9), corresponding stirrups are processed and formed in the early stage. According to accompanying drawing style 13, sectional drawing 14, sectional drawing 15 process sleeve steel bar.

Binding steel bars. According to the attached drawings 2, 5, 6, make the pouring formwork of the test piece, according to the attached drawings 3, 5, 6, use steel wires to tie the lower steel bars at the beam end such as the column longitudinal reinforcement (7), the column stirrups (8), the node stirrups (9) Binding is carried out, wherein the column stirrup (8) spacing is 80mm, and the node stirrup (9) spacing is 87.5mm. Then the beam longitudinal bars (5) and beam stirrups (6) that are sheathed with sleeve pipe (12) are bound, wherein the beam longitudinal bars (5) are arranged in double layers, and the beam stirrups (6) spacing is 80mm. Arrange and bind the upper reinforcement (10) and the lower reinforcement (11) according to accompanying drawings 9 and 10, wherein each reinforcement is orthogonal to the direction of the beam end.

The lower part of the prepared c60 high-type concrete pouring concrete column (2) is fully vibrated with a vibrating device. Immediately afterwards, the prepared c30 low-type concrete is poured into the concrete beam (1), concrete core area (3), and concrete slab (4), and is also fully vibrated, and the surface of the slab is wiped with tools, and the lower concrete such as the beam slab is initially set. Afterwards, the upper column longitudinal reinforcement (7) and the column stirrup (8) are bound and formworked, and the unfinished concrete column (2) at the upper end continues to be poured with high-type concrete.

After the concrete curing period of the test piece expires, the formwork is removed to obtain a space sandwich node with casings to improve the seismic performance.

The method of adopting PVC casing and steel pipe casing is only different in the material of the casing, and the rest of the construction process is as above.

Claims (7)

1. take sleeve pipe to improve the sandwich node in space of anti-seismic performance, it is characterised in that: the sandwich node in this space is by beams of concrete (1), concrete column (2), concrete core district (3), concrete slab (4), beam indulge muscle (5), beam stirrup (6), post indulge muscle (7), post Stirrup (8), node stirrup (9), upper plate muscle (10), lower plate muscle (11) and sleeve pipe (12) composition；

Concrete column (2) is longitudinally arranged, and each beams of concrete (1) is mutually orthogonal is horizontally placed at concrete column (2) middle part, concrete core Heart district (3) is the structure that crosses between beams of concrete (1), concrete column (2), and concrete slab (4) is between each beams of concrete (1) And top and beam top sentences same plane；Beam is indulged muscle (5) and is arranged two-layer and run through beams of concrete (1), and post indulges muscle (7) the most all Even layout, beam stirrup (6), column tie-bar (8) indulge muscle (5) at corresponding beam respectively, post is indulged muscle (7) colligation and is evenly arranged, node hoop Muscle (7) indulged by muscle (9) the uniformly colligation post in concrete core district (3) place, and upper plate muscle (10), lower plate muscle (11) are at concrete slab (4) arrange up and down in and reinforcing bar is mutually perpendicular to.

The sandwich node in the space taking sleeve pipe to improve anti-seismic performance the most according to claim 1, it is characterised in that: described Beams of concrete (1), concrete core district (3), concrete slab (4) take the concrete of low model.

The sandwich node in the space taking sleeve pipe to improve anti-seismic performance the most according to claim 1, it is characterised in that: described Concrete column (2) takes the concrete of high model.

The sandwich node in the space taking sleeve pipe to improve anti-seismic performance the most according to claim 1, it is characterised in that: described Beam indulges muscle (5), muscle (7) indulged by post, node stirrup (9) uses HRB400 reinforcing bar, described beam stirrup (6), column tie-bar (8), upper plate Muscle (10) and lower plate muscle (11) use HPB300 reinforcing bar.

The sandwich node in the space taking sleeve pipe to improve anti-seismic performance the most according to claim 1, it is characterised in that: sleeve pipe (12) internal diameter indulges muscle more than beam and length is equal to post width, and the internal diameter of sleeve pipe is not more than beam and indulges the diameter 6mm of muscle, in preventing sleeve pipe Footpath is excessive, and to cause sleeve pipe and beam to indulge muscle gap wide and cause concrete to flow into thus affect the insulating effect of sleeve pipe.

The sandwich node in the space taking sleeve pipe to improve anti-seismic performance the most according to claim 1, it is characterised in that: constructed Journey, first completes reinforcing bar binding, and core space beam is indulged muscle and put sleeve pipe, and when formwork pours, beam, plate and core space take low model of the same race Concrete, high model concrete taked by post；Pour order and be followed successively by lower post, beam slab core space, upper post.

7. the sleeve pipe of taking utilizing that the sandwich node in space described in claim 1 carries out improves the sandwich node in space of anti-seismic performance Construction method, it is characterised in that: the method comprises the steps, step one: according to construction drawing, blanking reinforcing bar, prepares to be wanted The different model concrete poured；

Step 2: vertical muscle stirrup is carried out early stage processing according to accompanying drawing, is placed in sleeve pipe regulation beam and indulges in the middle part of muscle；

Step 3: assembling reinforcement, completes coupled columns with steel wire and indulges the colligation of muscle stirrup, during stirrup colligation by lower and on carry out successively； Beam is indulged muscle insert at core space, be two-layer up and down and arrange, complete beam stirrup and beam are indulged the colligation of muscle with steel wire, note It is cased with the beam of sleeve pipe to indulge muscle and be in the middle part of internal layer；

Step 4: complete reinforcing bar binding, carries out formwork and pours；First with under the high model concreting post got ready when pouring Portion, with at low model concreting beam slab and core space after fully vibrating, continues to vibrate, floating concrete slab, upper post Continue, with high model concreting, to vibrate equally uniformly；

Step 5: maintenance test specimen, i.e. collapsible die molding after 28 days expire.