Leakage of steel bars in the concrete of high rise buildings!

High-rise buildings. The leakage of the reinforcement head in the concrete is a point-shaped reinforcement head, which is a normal situation, which may be a positioning and placement of the reinforcement, or it may be a tension bar, and the protective layer of the concrete is relative to the linear and surface reinforcement. It is necessary to do anti-rust treatment on these steel heads before scraping the wall, and scrape and plastering them during decoration without any impact on the structure.

If a lot of steel bars leak out in a linear form, I believe that the supervisor will not let them pass and need to be reworked.

Exposed ribs refer to reinforced concrete.

The vibration is not in place during the pouring process, the protective layer cushion block is not set or fixed firmly, and the concrete slump.

Small, or early demoulding, the concrete is exposed after the concrete is formed due to spalling caused by external force before hardening.

Walls? Oh... This is an earthquake-resistant shear wall, which is only used for shear resistance when it is **, so you don't need to worry, let the decorator scrape the wall flat.

The only thing to note is that if the wall is treated with moisture for a long time (such as the kitchen and bathroom), these steel bars need to be treated with anti-rust treatment before the wall is scraped flat, otherwise the wall may appear rust spots in the future.

The problem should not be big, it should be when tying the steel bar, the protective layer is not enough, and you should pay attention to it when decorating.

It may be that the steel bar is placed in an improper position or the steel bar is too long, and the concrete protective layer is not enough, which is defective, but the problem is not big, and it is good to cover it when decorating.

As you said, there are a lot of rebar heads, I guess there is no problem with the point of rebar heads, it is a normal situation, it may be a positioning and placement of reinforcing bars, or it may be tension reinforcement, and the protective layer of concrete is relative to linear and surface reinforcing bars. If a lot of steel bars leak out in a linear form, I believe that the supervisor will not let them pass.

When decorating, just scrape and plaster, and have no impact on the structure.

Structural system of concrete structure of high-rise buildings:

The structural system of multi-high-rise buildings is mainly divided into frame structure, shear wall structure, frame-shear wall (cylinder) structure, and hybrid structure system from large to direction. Multi-high-rise buildings should be selected according to factors such as the height, height-width ratio, seismic fortification category, seismic fortification intensity, site category, structural materials and construction technical conditions.

1.Frame structure.

Characteristics of the frame structure system.

The frame structure is composed of rigid connections of beams and columns.

Advantages: the spacing of the column network can be large or small, the building layout is flexible and easy to obtain a large use space, and the reinforced concrete ductile frame structure has good seismic performance.

Disadvantages: small lateral stiffness and large lateral deformation.

Scope of application of frame structure: suitable for those that require large space, the number of floors should not be too many, and the height of the house.

Buildings that should not be too high, such as teaching buildings, shopping malls, stations, exhibition halls, parking garages, hotels, etc. The construction height should be less than 60m. The frame should be arranged vertically and horizontally to form a two-way anti-lateral force system, and the lateral deformation of the frame structure under the action of horizontal force is characterized by shear type.

When the frame structure is used in relatively high buildings, large beams and columns are required to meet the requirements of the lateral deformation limit, and the economic indicators are not good.

2.Shear wall structure.

Characteristics of the shear wall structural system.

Shear wall structures are made of reinforced concrete walls that bear vertical loads and resist horizontal loads.

Advantages: The ability of the shear wall to bear both vertical and horizontal loads is large. It is characterized by good integrity, large lateral stiffness, small lateral displacement under the action of flat force, and because there are very few beams, columns and other exposed and protruding, it is convenient for the internal layout of the room.

Reinforced concrete ductile shear wall has good seismic performance.

Disadvantages: The spacing of the shear wall is small, the plane layout is not flexible, and it cannot provide a large space house.

Due to the large ability to withstand both vertical and horizontal forces and the large lateral stiffness, the shear wall structure can build a building with a higher and more floors than the frame structure. However, it can only be a house with small rooms, such as houses, hotels, and single dormitories. When a large space is needed in the basement or the lower part of the basement or several floors (such as shopping malls, foyers, parking garages, etc.), a partially frame-supported shear wall structure is formed.

A transition layer must be set in the transition layer of two different structures, the frame shear wall structure and the shear wall structure. The most widely used shear wall structure is 10 to 30 storey high-rise residential buildings. Very tall shear wall structures are not economical.

Scope of application: In order to apply the horizontal force (or ** action) in any direction, for the rectangular plane, the shear wall should be set in both vertical and horizontal directions; For circular planes, shear walls should be set in the radial and circumferential directions; In the triangular plane, it is advisable to set shear walls along the three main axis directions. The lateral deformation of the shear wall structure under the action of horizontal force is characterized by a curved type.

Regarding the connection of steel bars, this revision has major changes compared with the past:

1 In the past, for the key parts of the structure, the connection of steel bars was required to be welded, but now it is advisable to use mechanical connection. This is because it is difficult to ensure the quality of welding at present, while the mechanical connection technology is relatively mature, and the quality and performance are relatively stable. In addition, in the 1995 Hanshin ** earthquake in Japan, it was observed that the longitudinal steel bars of the column using air pressure welding were pulled off at the welding part in many places.

2. When the lap joint is adopted, the non-seismic design allows 100 lap joints in the same section of the component, but the lap length should be appropriately lengthened. This is more advantageous for lap joints of column longitudinal bars. In addition, it is also possible to lap the rebar in the same cross-section without having to weld the rebar one by one, as was the case in some past.

The extension length of the negative moment reinforcement on the top surface of the beam in this drawing, when the span difference of the adjacent beam is large, should be determined separately according to the actual force.

The structural system of high-rise buildings mainly includes: frame structure, frame shear wall structure, shear wall structure, frame support shear wall structure, cylinder structure and other frame structures, which are structures composed of longitudinal beams, beams and columns, and this structure is the structure of the skeleton that beams and columns are rigidly connected. Advantages of frame construction:

High strength, light weight, good integrity and seismic resistance, flexible column network layout, convenient to obtain a larger use space; The construction is simple and economical; Weaknesses of frame structure: small anti-lateral stiffness and large lateral movement; It is sensitive to the uneven settlement of the bearing. According to the analysis, when the height of the frame house increases, the lateral force action increases sharply, and when the building reaches a certain height, the lateral displacement will be large, and the internal forces generated by the horizontal load far exceed the internal forces generated by the vertical load.

Generally, it is suitable for houses with less than 10 floors and about 10 floors. Frame shear wall structure, also known as frame shear structure, frame-shear wall structure system refers to the multi-storey (high) floor house structure system that is jointly used as a vertical load-bearing structure by frame and shear wall. It is to set up several reinforced concrete walls (shear walls) between columns at appropriate positions in the longitudinal and transverse directions of the frame.

In this structure, the frame is stressed in tandem with the shear wall, which bears most of the horizontal load, and the frame bears the vertical load, so that the cross-section of the column can be reduced. Shear walls limit the flexibility of building layout to a certain extent. The frame-shear wall structural system gives full play to the characteristics of the frame and the shear wall, which can not only obtain the flexible space of large space, but also have strong lateral stiffness.

Therefore, this structural form is more commonly used in house design. This system is generally used in office buildings, hotels, residences and certain craft buildings. Frame-shear wall structure, generally used for house structures below 25 floors.

The shear wall structure is a structure composed of longitudinal and transverse reinforced concrete walls, that is, the structure adopts the structural system of shear walls. In addition to resisting horizontal and vertical loads, the wall also plays an enveloping and dividing role for the house. The advantages of shear wall structure are good integrity, large lateral stiffness, suitable for higher high-rise buildings, small lateral displacement under the action of horizontal force, and because there are no exposed components such as beams and columns, it can not affect the use function of the house.

The disadvantage is that due to the constraint of the position of the shear wall, the division of the internal space of the building is relatively narrow, and the large space house cannot be provided, and the structural ductility is poor. Therefore, it is more suitable for hotels and residences. Full shear wall structures are often used in 25 to 30-storey structures.

The cylinder structure is a structural form that uses a reinforced concrete wall to enclose a cylinder with great lateral stiffness. Under the action of lateral wind load, the force characteristics of the cylinder are similar to a cylindrical cantilever member fixed on the foundation. The windward side will be stretched, while the leeward side will be compressed.

The cylinder structure can be divided into single tube, cylinder-in-cylinder system, truss cylinder system, bundle cylinder system, etc. The cylinder can be a shear wall or a dense column frame; It is also possible to use different quantities of cartridges according to actual needs. The cylinder structure is mostly used in high-rise or super high-rise public buildings.

The tubular structure is used for super high-rise housing structures with more than 30 floors, and the economic height is limited to no more than 80 floors.

It should be a high-rise level that is second-level seismic resistant.

China's General Principles for the Design of Civil Buildings (GB

50352-2005) divides residential buildings into low-rise residential buildings according to the number of floors: low-rise residential buildings on the first floor to the third floor, multi-storey residential buildings on the fourth to sixth floors, medium and high-rise residential buildings on the seventh to ninth floors, and high-rise residential buildings on the tenth floor and above.

Except for residential buildings, civil buildings with a height of no more than 24m are single-storey and multi-storey buildings, and those with a height of more than 24m are high-rise buildings (excluding single-storey public buildings with a building height of more than 24m); Civil buildings with a building height of more than 100m are super high-rise buildings. From the perspective of architectural expertise, a multi-storey building refers to a building with a building height of more than 10 meters, less than 24 meters (10 meters "multi-storey building height< 24 meters), and the number of building floors is greater than 3 floors and less than 7 floors (3 floors "Floor < 7 floors"). In the new "High Regulations", namely the "Technical Regulations for Concrete Structures of High-rise Buildings" (JGJ3 2002), it is stipulated that:

Reinforced concrete structures with 10 or more floors or more than 28 m in height are called high-rise building structures. When the building height exceeds 100m, it is called a super high-rise building.

The content of shear wall structures (such as small high-rise and high-rise) per square meter of construction area: the formwork area is about to square meters, the concrete is about cubic meters, and the steel bar is about 60 to 75kg.

The content of non-residential frame structure per square meter of construction area (excluding basement): formwork area is about square meters, concrete is about cubic meters, and steel bars are about 50 to 60kg.

The content of multi-storey residential frame structure per square meter of construction area: formwork area is about square meter, concrete is about cubic meter, and steel bar is about 55 to 65kg.

The content of the basement per square meter of construction area: the formwork area is about to square meters, the concrete is about to cubic meters, and the steel bar is about 125 to 170kg.

High-rise buildings.

Technical Regulations for Concrete Structures

3 3 1 The maximum applicable height of reinforced concrete high-rise building structures should be divided into class A and class B. The maximum applicable height of Class A height reinforced concrete Class B and Class C high-rise buildings shall comply with the provisions of Table 3 3 1-1, and the maximum applicable height of Class B height reinforced concrete Class B and Class C high-rise buildings shall comply with the provisions of Table 3 3 1-2.

For high-rise building structures with irregular plane and vertical directions, the maximum applicable height should be appropriately reduced.

Reinforced concrete high-rise building structures are divided into Class A and Class B according to the maximum applicable height. For details, see Section 3 of Chapter 3 of the Technical Regulations for Concrete Structures of High-rise Buildings.

High-rise construction of reinforced concrete concrete.

The division of the height of DU building structure A and B grade.

ZHI: A-level high DAO: the height of the structure is not large and within the "High Specification" (Rong JGJ3-2010) (the maximum applicable height of the table;

Class B height: The height of the structure is greater than the maximum applicable height of class A, but not greater than the maximum applicable height of the table (JGJ3-2010) (table;

The height-to-width ratio of the building structure of Class A height and Class B height must meet the requirements of the "High Specification" (JGJ3-2010) (table).

The main structural system of high-rise residential buildings is the reinforced concrete shear wall structure, the number and position of the reinforced concrete shear wall are determined according to the specific house plane and function, the shear wall is usually a part, and a large number of filled masonry walls, windows, etc. are also used, and the external wall is all shear wall is very rare.

In the masonry structure house, a closed reinforced concrete beam is arranged in the masonry along the horizontal direction to improve the spatial rigidity of the house, increase the integrity of the building, improve the shear and tensile strength of the masonry, and prevent the damage to the house due to uneven settlement of the foundation, or other large vibration loads.

The continuous reinforced concrete beam in the upper part of the foundation of the house is called the foundation ring beam, also called the ground circle beam (DQL); In the upper part of the wall, the reinforced concrete beam next to the floor slab is called the upper ring beam. Because the ring beam is a continuously enclosed beam, it is called a ring beam.

If you're buying a house, it's good to be fully reinforced concrete.

1. The structure is integral.

2. Good leakage resistance.

Generally, it is a frame cast-in-situ reinforced concrete structure. Just lay more bricks.