What are the various building reinforcement methods?

The general methods of direct reinforcement are:

1, increase the cross-section reinforcement method

The method of construction technology is simple, adaptable, and has mature design and construction experience; applicable to the reinforcement of beams, slabs, columns, walls, and the general structure of the concrete; however, the on-site construction of the wet work time is long, and has a certain impact on the production and life, and after the reinforcement of the building headroom has been somewhat Reduction.

2, replacement of concrete reinforcement method

The advantages of the method and increase the cross-section method is similar, and reinforcement does not affect the headroom of the building, but there are the same shortcomings of the construction of the wet work time is long; applicable to the compression zone of the concrete strength of the concrete is low or serious defects in the beams, columns, and other concrete load-bearing components of the reinforcement.

3, bonded outsourcing steel reinforcement method

The method is also known as wet outsourcing steel reinforcement method, reliable force, construction is simple, the site workload is small, but the amount of steel is large, and should not be used for more than 600C high temperature places without protection; applicable to the use of the original members are not allowed to significantly increase the size of the cross-section, but also required to significantly increase its load-bearing capacity of the concrete structure! Reinforcement.

4, paste steel reinforcement method

The method of rapid construction, no wet work on site or only a small amount of wet work such as plastering, the impact on production and life is small, and after reinforcement of the original structure appearance and the original headroom has no significant impact, but the effect of reinforcement depends largely on the gluing process and level of operation; applicable to bear the role of static force and in the normal humidity of the bending or tensile components of reinforcement. The reinforcement.

5, paste fiber reinforced plastic reinforcement method

In addition to similar advantages of paste steel plate, but also has the advantages of corrosion resistance, moisture resistance, almost no increase in structural weight, durability, low maintenance costs, etc., but the need for special fire protection, applicable to a variety of nature of the force of concrete structural components and general structures.

6, around the wire method

The advantages and disadvantages of the method and increase the cross-section method is similar; suitable for concrete structural members of the diagonal cross-section of the insufficient bearing capacity of the reinforcement, or need to be compressed members of the transverse binding force of the occasion.

7, anchor bolt anchoring method

This method is applicable to the concrete strength grade C20 ~ C60 concrete load-bearing structure of the transformation, reinforcement; not applicable to the above structure has been severely weathered and lightweight structure.

The general methods of indirect reinforcement are:

1, pre-stressing reinforcement method

This method can reduce the stress level of the reinforced member, not only make the reinforcement effect is good, but also can improve the overall structural bearing capacity, but the reinforcement of the appearance of the original structure has a certain impact; applicable to the reinforcement of large-span or heavy structure as well as in the state of high stress, high strain Reinforcement of concrete members, but in the case of unprotected, can not be used in temperatures above 600C environment, and should not be used in the structure of the concrete shrinkage creep.

2, increase the support reinforcement method

The method is simple and reliable, but easy to damage the original appearance of the building and the use of the function, and may reduce the use of space; applicable to the specific conditions allow the reinforcement of concrete structures.

Techniques used in conjunction with concrete structure reinforcement and transformation generally include:

1. Joining technology

The general name of joist (or truss, the same as below) demolition of columns (or walls, the same as below), joist joining columns, and joist replacement of columns and other technologies; it is a kind of comprehensive technology composed of the relevant structural reinforcement, superstructure jacking and reset, as well as demolition of discarded components and other technologies; it is applicable to the reinforcement of existing buildings; it is also applicable to the reinforcement and transformation of existing buildings. It is applicable to the reinforcement and renovation of existing buildings; compared with the traditional practice, it has the advantages of short construction time, low cost, and small impact on life and production, etc. However, it has higher technical requirements and needs to be completed by skilled workers to ensure safety.

2, rebar implantation technology

is a more simple and effective connection and anchoring technology for concrete structure; can be implanted with ordinary rebar, can also be implanted with bolt-type anchors; has been widely used in the reinforcement of existing buildings and renovation projects, such as: omission of buried rebar in the construction or rebar deviation from the design position of the remedial components to increase the cross-section of reinforcement of reinforcement, the expansion of superstructure, the jacking beams, columns, house addition to connect the columns The length of the beams and columns of the superstructure expansion and jacking, and the reinforcement planting of the shear walls of the high-rise buildings and the columns of the houses and high-rise buildings.

3, crack repair technology

According to the cause of concrete cracks, traits and size, the use of different sealing methods for repair, so that the structure due to cracking and reduce the use of functionality and durability can be restored to a specialized technology; applicable to all types of cracks in the existing buildings, but the force of the cracks, in addition to repair, but should be used in addition to the corresponding reinforcement measures.

4, carbonized concrete repair technology (immature)

This refers to the restoration of alkaline concrete (passivation) or increase its impedance to carbonation caused by steel corrosion is curbed by the technology.

5, concrete surface treatment technology

This refers to the use of chemical methods, mechanical methods, sandblasting methods, vacuum vacuum methods, water jetting methods, etc. to clean up the surface of the concrete stains, oil stains, residue, and other adhesion of the specialized technology.

6, concrete surface sealing technology

This refers to the use of flexible sealant filling, polymer grouting, coating and other methods of waterproofing, moisture and crack-proofing of concrete treatment technology.

7, other technologies

such as structure, component displacement technology, adjusting the structural self-vibration frequency technology.

Masonry structure reinforcement methods:

The reinforcement of masonry structure is divided into two categories: direct reinforcement and indirect reinforcement, the design, according to the actual conditions and the use of the requirements to choose the appropriate method.

Applicable to the masonry structure of the direct reinforcement method is generally:

1, reinforced concrete plus layer reinforcement method

The method belongs to the composite cross-section reinforcement method. Its advantages are simple construction process, adaptability, masonry reinforcement bearing capacity has a greater increase, and has a mature design and construction experience; applicable to columns, with wall wall reinforcement; its disadvantage is that the site construction of wet work time is long, there is a certain impact on the production and life, and reinforcement of the building headroom has a certain reduction.

2, reinforced cement mortar plus layer reinforcement method

This method belongs to a composite cross-section reinforcement method. Its advantages and reinforced concrete plus layer reinforcement method is similar, but to improve the bearing capacity than the former; for masonry wall reinforcement, sometimes also used for reinforced concrete plus layer reinforcement with wall column wall on both sides of the hoop through the wall closed.

3, the addition of wall column reinforcement method

The method belongs to increase the cross-section of a reinforcement method. Its advantages are also similar to the reinforced concrete plus layer reinforcement method, but the bearing capacity is limited, and it is difficult to meet the seismic requirements, generally only in non-seismic areas.

Applicable to the masonry structure of the indirect reinforcement method is generally:

1, non-bonded steel reinforcement method

The method belongs to the traditional method of reinforcement, the advantages of its construction is simple, on-site workload and wet work less, more reliable force; applicable to the masonry columns are not allowed to increase the original member cross-section size, but also require a substantial increase in the section of the masonry columns of the reinforcement; the shortcomings The disadvantage is that the cost of reinforcement is high, and need to use similar protective measures for steel structures.

2, prestressed strut reinforcement method

This method can greatly improve the bearing capacity of masonry columns, and the reinforcement effect is reliable; suitable for reinforcement treatment of high stress, high strain state of the masonry structure reinforcement; its disadvantage is that it can not be used for temperatures of 600C or more in the environment.

Tectonic reinforcement and repair of masonry structure

1, additional ring beam reinforcement

When the ring beam set does not meet the requirements of the current design specifications, or longitudinal and transversal walls at the junction of the bite of the rubbing with obvious defects, or the integrity of the house is poorer, should be added to the ring beam for reinforcement

2, the additional beam cushion reinforcement

When the large beams of the following brick masonry is locally crushed or large beams When the wall under the local vertical cracks, additional beam pads should be reinforced.

3, masonry local demolition

When the house partial rupture but in the cause of the rupture has not yet affected the load-bearing and safety, the rupture of the wall can be partially demolished, and according to improve the strength of the mortar one level with the whole brick filling.

4, masonry crack repair

Before the crack repair, should be based on the masonry components of the force state and crack characteristics and other factors, to determine the causes of masonry cracks, in order to targeted crack repair or the use of appropriate reinforcement measures.

Steel structure reinforcement methods:

The main methods of steel structure reinforcement are: load reduction, change the structural calculation graph, increase the original structural component cross-section and connecting strength, and stop the expansion of cracks. When there is mature experience, other reinforcement methods can also be used.

1, change the structural calculation graph

Changing the structural calculation graph of the reinforcement method refers to the use of changing the load distribution, force transmission paths, node properties and boundary conditions, the addition of additional rods and bracing, applying pre-stressing, consideration of spatial co-operation, and other measures for structural reinforcement;

Changing the structural calculation graph of the general reinforcement methods:

(1) The structure can be strengthened by the following methods of increasing the stiffness of the structure or members:

A, adding bracing to form a space structure and checking it according to the space structure;

B, adding bracing to increase the stiffness of the structure or adjusting the self-resonance frequency of the structure, etc. in order to increase the structural load carrying capacity and improve the structural dynamic characteristics;

C, adding bracing C, additional support or auxiliary rods so that the structure of the length of the slenderness ratio is reduced in order to improve its stability;

D, in the row structure focus on strengthening the stiffness of a column, so that it can withstand most of the horizontal force, in order to alleviate the load of the

other columns;

E, in the tower and other structures set up tie rods or moderately tensioned tension ropes in order to strengthen the rigidity of the structure.

(2) The following methods can be used to change the internal force of the section of the bending member to strengthen:

A, change the distribution of load, such as a concentrated load into a number of centralized load;

B, change the end support, such as articulation into a rigid junction;

C, increase the intermediate support or simply support the structure of the end of the structure connected to become a continuous structure;

D, Adjustment of the position of the support of a continuous structure;

E, Change of the structure into a brace structure;

F, Application of prestressing.

(3) The truss can be strengthened by the following methods to change the internal force of its rods:

A. Adding braces to change the truss into a brace-type structure;

B. Adding prestressing tie rods.

2, increase the cross-section of the reinforcement

Increase the cross-section of the reinforcement of steel members, the selected cross-section form should be conducive to the requirements of the reinforcement technology and take into account the existing defects and damage to the situation.

3. Connection of reinforcement and reinforcement

The selection of steel structure connection methods, i.e. welding, riveting, ordinary bolts and high-strength bolts, should be based on the reasons for the need to reinforce the structure, the purpose, the stress condition, the structure and the construction conditions, and the consideration of the structure of the original connection method to determine.

Steel structure reinforcement is generally appropriate to use weld connection, friction-type high-strength bolt connection, based on the basis of weld and friction-type high-strength bolts can also be used in the mixed connection. When the weld connection is adopted, the welding process and connection materials recognized by the evaluation shall be used.

4, crack repair and reinforcement

Structure due to repeated loads and material selection, construction, manufacturing, construction and installation of improper material selection, construction and installation of cracks with a tendency to expand or brittle fracture damage, should try to repair. Before repair, must analyze the causes of cracks and the severity of its impact, targeted measures to improve the actual work of the structure or reinforcement measures, it is not suitable for repair and reinforcement of the components, should be removed and replaced.

In the past 50 years, China's structural inspection and reinforcement technology has experienced the development process from scratch, from single to comprehensive, from local components to the overall structure. Especially in the last 20 years, the structural testing and reinforcement technology has been rapid development, and its application object has been expanded from the beginning stage of the single-story dilapidated residential to all kinds of structures in the construction project.

The development and application of structural testing and reinforcement technology has played a positive role in improving the quality of construction projects, and has also played a role in saving the funds of the state and enterprises, and guaranteeing the safety of enterprise production and people's lives and properties.