Structure based on ECC reinforcing plate column joint
Through the use of ECC materials at the pillar nodes for unilateral reinforcement, the problem of complex construction and drilling damage in existing technology is solved, and the anti -rush cutting performance and service life of the pillar node are improved.
Patent Information
- Application Number
- CN202420999922.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-09
- Publication Date
- 2025-01-28
- Estimated Expiration
- 2034-05-09
AI Technical Summary
In the existing column node reinforcement measures, drilling holes in the floor slabs need to be carried out, resulting in complex construction and damage to the floor slabs, as well as the addition of column caps and complex construction.
The cement base composite material (ECC) is used as a reinforcement module, and one -sided reinforcement is performed on the pull side of the pillar node. The reinforcement module is formed at the floor and the pillar connection by pouring the ECC material.
Improve the resistance of the pillar node, avoid damage to the drilling, simplify the construction process, reduce the cost, and extend the service life of the pillar node.
Smart Images
Figure CN222414180U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field related to building construction, and more specifically, relates to a plate-column node based on ECC reinforcement. Background Art
[0002] The slab-column structure has the advantages of simple structure, convenient construction, and high floor clearance. It has been widely used in engineering nodes such as large shopping malls, underground garages, and subway platforms. However, the slab-column node is very prone to brittle shear failure under the action of external loads, which in turn leads to the continuous collapse of the overall structure.
[0003] In order to solve the problem of poor shear resistance of slab-column joints, appropriate reinforcement measures can be taken to improve the shear resistance of slab-column joints. At present, the reinforcement measures for slab-column joints mainly include: (1) adding column caps; (2) carbon fiber reinforcement; (3) FRP reinforcement. These technical measures have improved the resistance reserve of slab-column joints to a certain extent, but there are also the following problems: (1) The construction of adding column caps is complicated and difficult to implement, and it limits the spatial layout and affects the appearance; (2) Carbon fiber reinforcement technology needs to be fixed with steel plates and anchor bolts, and the location where the anchor bolts are placed needs to be drilled, which will cause certain damage to the reinforced floor slabs. In the actual construction process, the operation is relatively complicated and the floor slabs are not easy to drill. (3) FRP reinforcement technology also requires drilling holes in the floor slabs, which will undoubtedly cause damage to the original floor slabs, and there is also the problem of construction difficulties. Utility Model Content
[0004] In view of the above defects or improvement needs of the prior art, the utility model provides a structure based on ECC reinforcement of plate-column nodes, which solves the problems of the need to drill holes in the floor slab, add column caps and complex construction in the existing reinforcement measures.
[0005] To achieve the above object, according to one aspect of the utility model, a structure based on ECC reinforced plate-column node is provided, the structure comprising a floor slab, a column and a reinforcement module, wherein:
[0006] The column penetrates the floor slab to form a plate-column structure, the reinforcement module surrounds the column and is arranged at the connection between the floor slab and the column, and the reinforcement module is only arranged on the tension side of the node at the connection between the floor slab and the column. The column is arranged under the floor slab to support the floor slab, and the reinforcement module surrounds the column and is arranged at the connection between the floor slab and the column.
[0007] Further preferably, the thickness of the reinforcement module is 1 / 5 to 1 / 3 of the plate thickness, but not less than 30 mm.
[0008] Further preferably, the distance between the outermost side of the reinforcement module and the outer circumference of the column is 1.5 to 2 times the thickness of the floor slab.
[0009] Further preferably, the reinforcement module is cast using cement-based composite materials.
[0010] Further preferably, the reinforcement module is also provided on the side of the connection between the floor slab and the column opposite to the tension side.
[0011] Further preferably, an interface agent layer is provided on the surface of the floor slab and the column at the connection between the floor slab and the column, so as to improve the bonding strength between the reinforcement module and the floor slab and the column.
[0012] Further preferably, the column is a reinforced concrete slab-column structure.
[0013] In general, the above technical solutions conceived by the utility model have the following beneficial effects compared with the prior art:
[0014] 1. In view of the problems that the existing conventional reinforcement technology for slab-column joints is complicated to construct and requires drilling holes in the floor slab, the utility model uses engineering cement-based composite materials (ECC) as reinforcement modules on the tension side of the slab-column joint to improve the shear resistance of existing ordinary reinforced concrete slab-column joints. There is no need to drill holes, add column caps and support plates, and the size of the original components is not increased. The construction is convenient and no large equipment is required.
[0015] 2. The reinforcement module of the utility model adopts cast ECC material. The ECC material has high tensile strength and good deformation ability. When used to reinforce the plate-column node, it plays a role of reinforcement, strengthening and toughening, improves the bearing capacity, deformation capacity and overall performance of the plate-column node, and is expected to change the nature of brittle failure of the plate-column node and extend the service life of the plate-column node.
[0016] 3. The utility model adopts single-sided reinforcement. Compared with the double-sided reinforcement of the previous technology, the utility model is low-priced, simple and convenient to construct, has little destructiveness to the original plate-column nodes, and avoids the problem of additional drilling in the floor slab and construction difficulties.
[0017] 4. Compared with the solution in the prior art that directly replaces the connection between the floor slab and the column with ECC material during the floor slab construction process, the utility model can not only reinforce the newly built slab-column nodes, but also reinforce the existing slab-column nodes. In addition, the utility model uses relatively less ECC for reinforcing the slab-column nodes, has low cost and convenient construction. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 It is a side sectional view of a structure based on an ECC reinforced plate-column node constructed according to a preferred embodiment of the utility model.
[0019] Figure 2It is a side view of a structure based on ECC reinforced plate-column nodes constructed according to a preferred embodiment of the utility model.
[0020] Figure 3 It is a top view of a structure based on ECC reinforced plate-column nodes constructed according to a preferred embodiment of the utility model.
[0021] Figure 4 It is a structural schematic diagram of the width of the reinforcement module constructed according to the preferred embodiment of the utility model.
[0022] Figure 5 It is a side view of a column constructed according to another preferred embodiment of the utility model that does not penetrate the floor.
[0023] Figure 6 It is a top view of a column constructed according to another preferred embodiment of the utility model that does not penetrate the floor.
[0024] In all drawings, the same reference numerals are used to denote the same elements or nodes, wherein:
[0025] 1- Floor slab, 2- Column, 3- Reinforcement module. DETAILED DESCRIPTION
[0026] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the utility model and are not used to limit the utility model. In addition, the technical features involved in each embodiment of the utility model described below can be combined with each other as long as they do not conflict with each other.
[0027] The utility model is composed of an ordinary reinforced concrete slab-column node and a reinforcement module 3, the slab-column node includes a floor slab 1 and a column 2 penetrating the floor slab, the reinforcement module 3 is a single-side reinforcement, that is, on the tension side of the slab-column node, the reinforcement module 3 is formed by pouring ECC (Engineered Cementitious Composites) cement-based composite material.
[0028] Before reinforcement, the pouring thickness and reinforcement range of ECC materials need to be determined. 5.5.3 of the Code for Design of Concrete Structure Reinforcement (GB50367-2013) states that when a new concrete reinforcement plate is used, the minimum thickness of the new concrete layer should not be less than 40mm. Considering the excellent mechanical properties of ECC, when ECC is used to reinforce the slab-column joint, the pouring thickness of ECC can be appropriately reduced, but it should not be less than 30mm. 9.1.2 of the Code for Design of Concrete Structures (2015 Edition) (GB 50010-2010) states that for beamless floor slabs (also known as slab-column joints), the minimum thickness of cast-in-place reinforced concrete slabs is 150mm. From the perspective of both reinforcement effect and cost, the pouring thickness of ECC is 1 / 5 to 1 / 3 of the floor slab thickness. Taking the floor slab thickness of 150mm as an example, 150*(1 / 5 to 1 / 3) = 30 to 50mm, which is a relatively ideal range. If the pouring thickness is too thin, the pouring effect may be weakened, and if the pouring thickness is too thick, the cost will be increased. In addition, the pouring thickness can be increased or decreased according to the actual damage of the slab-column joint. Figure 4 As shown in the figure, when the punching failure occurs in the concrete slab-column node, the punching angle is mainly distributed in the range of 25° to 35°, and the distance between the edge of the corresponding punching cone and the column is 1.5h to 2h (h is the thickness of the floor slab). Therefore, in order to prevent the punching failure of the slab-column node, the range of ECC material reinforcement is determined to be twice the thickness of the slab from the edge of the column. This reinforcement range covers the shear area when the slab-column node undergoes punching failure, thereby achieving a reinforcement effect, and can effectively avoid the punching failure of the slab-column node.
[0029] The interface failure mode between the ECC material and concrete when the reinforced slab-column joint is subjected to stress has a significant impact on the reinforcement effect. Therefore, ensuring that cohesive failure of the concrete (destruction of the existing concrete body) rather than interface failure occurs when the interface between the ECC material and the existing concrete is subjected to stress is the key to ensuring the reinforcement effect.
[0030] The processes for ensuring reliable bonding between new and old concrete interfaces mainly include: (1) achieving reliable bonding at the interface based on the bonding properties of fresh concrete itself, such as ECC materials; (2) achieving reliable bonding at the interface between new and old concrete based on high-performance interface agents.
[0031] In another embodiment of the utility model, the old concrete can be surface treated and coated with an interface agent to improve the bonding strength of the interface between the new and old concrete, making it higher than the tensile strength of the old concrete layer, achieving cohesive failure of the concrete, avoiding adhesion failure at the interface, and ensuring that the new and old concrete work together. In summary, the current construction process can achieve reliable bonding between high-strength ECC materials and concrete, ensuring cohesive failure of the base concrete when the interface is stressed.
[0032] In another embodiment of the present invention, Figure 5As shown, the column 2 in the slab-column joint does not penetrate the floor slab 1. Figure 6 This is a top view of the slab-column joint where the column does not penetrate the floor slab 1, and the reinforcement module is still set on the tension side.
[0033] The implementation method of the utility model is carried out in two steps: (1) preparing ECC material; and (2) pouring ECC material.
[0034] The following is a detailed introduction.
[0035] S1. Preparation of ECC Materials
[0036] 1.1 ECC material introduction
[0037] ECC material is a cement-based composite material prepared by adding short-cut fibers to cement mortars of different strengths. ECC has the characteristics of obvious strain hardening and multiple crack development. Common types of ECC externally mixed fibers include polyvinyl alcohol (PVA) fiber; polypropylene (PP) fiber; polyethylene (PE) fiber, etc. The ECC made is called PVA-ECC, PP-ECC, PE-ECC, etc.
[0038] ECC exhibits obvious strain hardening characteristics, ultra-high tensile and compressive toughness, excellent durability, good deformation capacity and energy dissipation capacity. It can be foreseen that the use of this material in plate-column nodes can improve the shear resistance of plate-column nodes and meet the requirements of safety, applicability and durability.
[0039] 1.2 ECC mix ratio
[0040] The utility model provides a PE-ECC mix ratio for reference.
[0041] Table 1 PE-ECC mix ratio (mass ratio)
[0042]
[0043] As can be seen from 1.1, different types of fibers can be added to prepare different types of ECC for strengthening plate-column joints.
[0044] S2. Casting ECC materials
[0045] The process of pouring ECC materials is as follows: (1) Determine the pouring thickness and pouring range of ECC according to the thickness of the slab; (2) Make the corresponding wooden formwork and support it before pouring; (3) Apply interface agent to the surface of the old concrete; (4) When pouring ECC, use a concrete vibrator to compact it, and finally smooth the surface of the reinforcement layer and cover the surface of the specimen with plastic wrap; (5) Remove the formwork after the ECC material has initially set for 48 hours, and then cure it at room temperature for 28 days.
[0046] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.
Claims
1. A structure based on ECC reinforced plate-column joints, characterized in that: The structure includes floor slabs, columns and reinforcement modules, among which, The column is arranged below the floor slab to support the floor slab, the reinforcement module surrounds the column and is arranged at the connection between the floor slab and the column, and the reinforcement module is only arranged on the tension side of the connection between the floor slab and the column, and the material of the reinforcement module is ECC; An interface agent layer is provided on the surface of the floor slab and the column at the connection between the floor slab and the column, so as to improve the bonding strength between the reinforcement module and the floor slab and the column.
2. A structure based on ECC reinforced plate-column joints as claimed in claim 1, characterized in that: The thickness of the reinforcement module is 1 / 5 to 1 / 3 of the thickness of the floor slab and is not less than 30 mm.
3. A structure based on ECC reinforced plate-column joints as described in claim 1 or 2, characterized in that: The distance between the outermost side of the reinforcement module and the outer circumference of the column is 1.5 to 2 times the thickness of the floor slab.
4. A structure based on ECC reinforced plate-column joints as claimed in claim 1 or 2, characterized in that: The reinforcement module is also provided on the side of the connection between the floor slab and the column opposite to the tension side.
5. A structure based on ECC reinforced plate-column joints as claimed in claim 1 or 2, characterized in that: The column is a reinforced concrete slab-column structure.
6. A structure based on ECC reinforced plate-column joints as claimed in claim 1 or 2, characterized in that: The column may or may not penetrate the floor slab.