The protective layer of the foundation stressed reinforcement is 4cm, and the longitudinal stressed

Concrete covering.

Article longitudinal stress of ordinary steel bars and prestressed steel bars, the thickness of the concrete protective layer (the distance from the outer edge of the steel bar to the concrete surface) should not be less than the nominal diameter of the steel bar, and should comply with the provisions of the table.

The minimum thickness of the concrete protective layer of the longitudinal stressed reinforcement (mm) Table environmental category slabs, walls, shells, beams and columns C20C25-C45 C50 C20C25-C45 C50 C20C25-C45 C50 201515302525303030 A-2020-3030-3030B-2520-3530-3530 C3-3025-4035-4035 Note:

The thickness of the concrete protective layer of the longitudinal stressed steel bar in the foundation should not be less than 40mm; When there is no cushion, it should not be less than 70mm

Article in a class of environment and prefabricated components produced by the factory, when the concrete strength grade is not less than C20, the thickness of the protective layer can be reduced by 5mm in accordance with the provisions of the table in this specification, but the thickness of the protective layer of the prestressed steel bar should not be less than 15mm; For prefabricated components in a Class II environment and produced by a factory, when effective protective measures are taken on the surface, the thickness of the protective layer can be taken according to the value of the Class I environment in the table of this specification.

The thickness of the protective layer at the end of the steel bar of the prefabricated reinforced concrete bending member should not be less than 10mm; The thickness of the protective layer of the main rib reinforcement of the prefabricated rib plate should be taken according to the value of the beam.

Article slabs, walls, shells in the distribution of steel bar in the thickness of the protective layer should not be less than the corresponding value in the table of this specification minus 10mm, and should not be less than 10mm; The thickness of the protective layer of stirrups and structural reinforcement in beams and columns should not be less than 15mm

Article when beams, columns in the longitudinal stress of the concrete protective layer thickness of the reinforcement is greater than 40mm, the protective layer should take effective anti-cracking structural measures.

In. Effective protective measures should be taken on the upper surface of the cantilever plate in the second and third class environments.

Article for buildings with fire protection requirements, the thickness of the concrete protective layer should meet the requirements of the current national standards.

In. The thickness of the concrete protective layer of the buildings in the fourth and fifth types of environments should still meet the requirements of the current national standards.

Please note the distinction:

1.The minimum thickness of the protective layer in the table of the "Concrete Code" refers to the thickness of the protective layer of the "outermost reinforcement", that is, the distance from the outer surface of stirrups or tension bars to the surface of the concrete;

2.The thickness of the protective layer of "stressed reinforcement" (in this case, the longitudinal stressed reinforcement) refers to the distance from the outer surface of the stressed reinforcement to the concrete surface. For example, this distance c stirrup diameter (c is the minimum thickness of the cover specified in the concrete specification table, c 15 50mm).

The thickness of the reinforced concrete is generally 3-5 cm.

The distance from the main reinforcement (excluding stirrups) skin to the concrete skin.

Minimum protective layer: 15mm for plates, 25mm for beams and columns, and not less than the diameter of the stressed steel bar.

Construction quality management is the quality of construction and installation products, which refers to the characteristics of products that are suitable for certain purposes and meet certain needs of people, including firmness, durability, economy, applicability, beauty and other attributes. The quality of construction and installation is a comprehensive response to the work of the construction enterprise, and it is an important symbol to measure the management level of an enterprise.

For construction quality management, total quality management must be implemented. Total quality management, to establish the viewpoint of prevention-oriented, user-oriented service and overall management, is a quality management method that focuses on all personnel of the enterprise, takes mathematical statistical methods as the basic means, and gives full play to the role of management, organization, technical work and logistics services in the enterprise.

The quality of construction depends on factors such as people, construction machinery and equipment, tools, raw materials, prefabricated components, construction methods, etc., and also involves the quality of raw materials and their transportation and storage, the integrity and operation of machinery and equipment, the technical level and proficiency of workers, whether the labor organization is advanced and reasonable, whether the quality inspection and testing methods are sound, and so on.

It is related to the environmental category and the strength of the concrete.

The minimum thickness of the protective layer of the plate is 15mm, the beam is 25mm, and the column is 30mm

Regardless of diameter.

See Code for Design of Building Foundations

gb 50007-2011

8 2 1 The construction of the extended foundation shall comply with the following provisions:

The edge height of the tapered foundation should not be less than 200mm, and the slope in both directions should not be greater than 1:3;The height of each step of the stepped foundation should be 300mm 500mm.

cushions. The thickness should not be less than 70mm, the strength grade of cushion concrete.

It should not be lower than C10.

The minimum reinforcement ratio of the stressed steel bar of the extended foundation should not be less than, the minimum diameter of the stressed steel bar of the bottom plate should not be less than 10mm, and the spacing should not be greater than 200mm or less than 100mm. The diameter of the longitudinally distributed reinforcement of the reinforced concrete strip foundation under the wall should not be less than 8mm; The spacing should not be greater than 300mm; per linear meter.

The area of the distributed reinforcement should not be less than 15 of the area of the stressed reinforcement. When there is a cushionThe thickness of the rebar coverIt should not be less than 40mm; When there is no underlayment, it should not be less than70mm

When there is no concrete cushion at the bottom of the foundation, the thickness of the reinforcement protective layer should not be less than 70mm.

In order to ensure the durability of the foundation reinforcement,According to the engineering experience, the bottom surface of the foundation is required to be used as a cushion, the thickness of the substrate protective layer is still 40mm. Therefore, there is no "when there is no concrete cushion at the bottom of the foundation, the thickness of the reinforcement protective layer should not be less than 70mm." "That's what it says.

When there is no cushion, the thickness of the protective layer of the reinforcement is not less than 70mm.

When there is no concrete cushion at the bottom of the foundation, the thickness of the protective layer of the reinforcement should not be less than 50mm

This question is detailed in the figure below

<> Note: (1) The thickness of the concrete protective layer in the table is suitable for concrete structures with a design service life of 50 years.

2) The thickness of the protective layer of the stressed steel bar in the component should not be less than the nominal diameter of the steel bar.

3) In a first-class environment, the thickness of the protective layer of the outermost reinforcement of the structure with a design service life of 100 years should not be less than the times of the value in the above table; In the second and third types of environments, special effective measures should be taken for structures designed with a service life of 100 years.

4) When the concrete strength grade is C25, the thickness of the protective layer in the table should be increased by 5mm.

5) The reinforced concrete foundation should be provided with a concrete cushion, and the thickness of the reinforcement protective layer at the bottom of the foundation should be calculated from the top surface of the cushion, and should not be less than 40mm; When there is no cushion, it should not be less than 70mm.

6) pile foundation cushion cap and cushion cap beam: the thickness of the reinforcement protective layer on the bottom surface of the cushion cap, when there is a concrete cushion, should not be less than 50mm; When there is no cushion, it should not be less than 70mm. In addition, it should not be less than the length of the pile head embedded in the cap.

The minimum thickness of the protective layer of the beam and column is 20mmThe minimum thickness of the protective layer of the board and wall is 15 mm

The thickness of the protective layer of the reinforcement is related to the service life of the concrete component, the type of environment in which it is located, and the strength grade of the concrete.

11G G101 The thickness of the reinforcement cover refers to the distance from the outermost reinforcement to the outer surface of the concrete.

11G101 (excluding 11G101 atlas) Atlas previously issued atlas, the minimum protective layer of reinforcement should not be less than the diameter of the stressed rib.

What is the specific protective layer of the reinforcement, please refer to page 56 of 16G101-1 in combination with the drawings:

Minimal protective layer of concrete.

What is the minimum thickness of the protective layer of a beam and column? What is the thickness of the protective layer of walls and panels? And it should not be less than that of the tendons.

Answer]: Hengtong is like b

The thickness of the concrete protective layer of the longitudinal stressed steel bar in the foundation should not be less than 40mm of wheel slag; When there is no cushion, it should not be less than 70mm

The thickness of the reinforcement cover in the beam is determined according to the relevant standards and design requirements. According to the Code for Design of Reinforced Concrete Structures (GB50010-2010), the thickness of the concrete protective layer should meet the requirements of the service life of the components, and also meet the requirements of the strength design of the concrete structure. Specifically, in general residential buildings, the thickness of the protective layer of the steel bars in the beam is usually between 20 and 30mm.

The thickness of the protective layer is related to the size of the beam, the working ring and the load-bearing level, etc., which need to be comprehensively considered in combination with the actual situation. In addition, for some special projects, such as high-strength concrete buildings, marine engineering, nuclear engineering, etc., the thickness of the protective layer of the steel bars in the beam may be different, which needs to be determined according to the specific design requirements.

Not only that, the requirements for the thickness of the protective layer of reinforced concrete beams are constantly increasing. At present, the nuclear bench is aimed at some special projects such as high-strength concrete components, and the thickness of the protective layer of the steel bar in the beam has generally reached more than 50mm to ensure the service life of the structure. For other special projects, such as seismic design and fire protection design, the thickness of the protective layer of the reinforcement in the beam may need to be further increased.

In short, the thickness of the reinforcement protective layer in the beam is not a fixed value, but is determined by comprehensive consideration according to factors such as the service life, strength requirements, working environment and bearing capacity of the structure, combined with relevant standards and design requirements. In the actual engineering design, it is necessary to accurately calculate and comprehensively consider various factors in order to formulate a safe and reliable thickness scheme of the reinforcement protective layer in the beam. <>

Summary. Hello, the engineering quantity of plate reinforcement is 12mm. The rebar cover is the distance from the outer edge of the outermost rebar to the concrete surface.

The distance from the outer edge of the outermost steel bar to the concrete surface, and the protective layer of the reinforced concrete column and beam refers to the stirrups. Stirrups are used to meet the shear strength of the oblique section and connect the main reinforcement and the mixed reinforcement skeleton in the compression zone.

It is known that the thickness of the beam protective layer is 20mm, the beam longitudinal reinforcement is 20mm, and the stirrup is 8mm, and the engineering quantity of plate reinforcement is calculated.

Hello, the engineering quantity of plate reinforcement is 12mm. The protective layer of the steel bar is the distance from the outer edge of the outermost steel bar to the surface of the ruined concrete. The distance from the outer edge of the outermost steel bar to the concrete surface, and the protective layer of reinforced concrete columns and beams refers to the stirrups that are quietly rotting.

Stirrups are used to meet the shear strength of the oblique section and connect the main reinforcement and the mixed reinforcement skeleton in the compression zone.

Hello, bridge structures, most of which are also concrete structures. The protective layer is the concrete in the middle from the concrete surface to the outermost steel bar. The thickness of the protective layer is different in different situations, and the thickness of the protective layer of the general eggplant potato is 20mm.

The thickness of the protective layer is 40mm when the tensile reinforcement of the tremor beam column is one row, and 65mm when it is two rows.

It is known that the thickness of the beam protective layer is 20mm, the beam longitudinal reinforcement is 20mm, and the stirrup is 8mm, and the engineering quantity of plate reinforcement is calculated.

I need the full calculation process.

Calculation formula: steel bar length = plate net span ln + length extending into the left and right supports + hook increase length. Calculation of specific data:

Bottom reinforcement length = net length + 2 * max (support width 2, 5d) + 2 * first-class reinforcement) + lap, number of roots = (net length - 2 * 50) spacing + 1, late space calendar gluten length = net length + 2 * la + 2 * first-class reinforcement) + lap, number of roots = (net length - 2 * 50) spacing + 1, la: non-seismic resistance; LAE: seismic resistance, end support negative code reinforcement length = net length + LA + plate thickness - 2 * protective layer), number of roots = (net length - 2 * 50) spacing + 1, middle support negative reinforcement length = left net length + right net length + 2 * (plate thickness loss seepage - 2 * protective layer).