What is a deformation joint, how should I understand it, how can I not see any cracks in the buildin

Deformation joints: Buildings are often deformed under the action of external factors, resulting in cracking and even destruction. A deformation joint is a construction joint that is reserved for this situation.

The same is true in construction projects, where gaps are also reserved in the design of the building to prevent the building from expanding and shrinking due to humidity and temperature, or to prevent uneven settlement of the building, or to prevent earthquakes.

Classification of deformation seams.

1) According to the use of the building parts, it is divided into:

Deformation joints of floors, exterior walls, interior walls, ceilings and ceilings, roofs, roofs.

2) Deformation joints are classified according to function:

There are three types of expansion joints, settlement joints and shockproof joints.

3) The parts of use are divided into:

Flat and corner.

4) According to the structural characteristics of the deformation joint device, it is divided into:

Metal cover type, metal card lock type, single row embedded flat type, double row embedded flat type, rubber embedded flat type.

Deformation joint is a general term for the partition of structural intervals that need to be taken for the deformation coordination of structural elements. The function is to divide the longer, more complex structural system into shorter, simpler structural units.

It is divided into: expansion joint, settlement joint, and seismic joint.

Expansion joints: mainly to solve the problem of temperature expansion, the longer the structural unit, the greater the temperature force, so according to different structural forms to set expansion joints at a certain distance.

Settlement joint: It is mainly to coordinate the uneven settlement of the foundation to avoid the additional effect on the superstructure caused by the uneven settlement caused by the uneven foundation on both sides or the uneven load of the upper load.

Seismic joint: The plane complex structural system is divided into a regular and simple structural system, so that the dynamic characteristics of the structural unit are more reasonable.

The deformation joints generally have corresponding architectural structures, which are difficult to see on the façade due to the obstruction of some decorative panels. However, it is still easy to identify when entering the interior, and it is easy to see the dividing strip on the floor and easier to identify on the roof, because the deformation joint will have a higher bulge at the location.

It's the seam between the houses.

In order to prevent the use and safety impact of the building due to factors such as temperature changes, uneven settlement and **, we should disconnect the building in the deformation sensitive part in advance when designing the building structure, and divide it into a number of relatively independent units, and the reserved gap can ensure that the building has enough deformation space, and the structural joint that is set up is called the deformation joint. After setting the deformation joint, the building can avoid damage caused by the above factors.

Ordinary people think that the house is so strong, it is unchanged, and it is not deformed. Actually, all objects, there is nothing that does not change.

When the temperature is high during the day, the house will be slightly larger, and at night, when the temperature is low, the house will be slightly smaller. There are slight variations in the temperature when the temperature is high in summer and low in winter. You look up the coefficient of expansion of various substances and see.

The coefficient of linear expansion of steel is 12 10-6. (The coefficient of expansion of concrete is about the same as that of steel.)

For a 60-meter building, the temperature is -6 degrees in winter and 60 degrees in summer (not the air temperature, but the surface temperature of the building). The difference reaches 66 degrees. For a member with a length of 30 meters, its length can vary by meters up to 66 degrees millimeters, i.e. nearly centimeters.

Such a large deformation is enough to cause cracking of concrete.

Secondly, the foundation (soil) will also be compressed, expanded and deformed due to pressure or rainwater soaking. For example, in a high-rise building, the center part of the excavation is too deep, and the backfill is compacted, but when the observation is carried out, it is found that the backfill area is 20mm more than the original soil area, and this different settlement will cause the building to crack.

There are other reasons for the deformation of buildings. Some are not a**.

In order to prevent the deformation of the building from causing damage to the building, it is necessary to set up deformation joints——— you can change it if you want to deform, as long as it is a small local shape, do not cause damage to the entire building.

Prevent excessive temperature stress from causing excessive and excessive cracks in structural components, and prevent uneven settlement of the foundation from causing cracks.

The main purpose of the installation of building deformation joint device is to meet the requirements of thermal expansion and contraction, free settlement, seismic resistance and other requirements of Paifeng Hall building, and its function is mainly to meet the covering and decoration of building expansion joints, settlement joints and seismic joints, and at the same time meet the requirements of expansion and contraction, settlement, dust and earthquake resistance.

First of all, the deformation joints can strengthen the integrity of the building, so that our buildings have sufficient strength and rigidity, and the main performance of these deformation joints can effectively overcome various damage in the environment, and our buildings can exist better.

Secondly, there is a major function, that is, when doing deformation joints, it is to disconnect the structure of these deformation sensitive parts in advance, so that there is a certain gap between the buildings, and the guarantee of the width of this deformation joint is to make our buildings have enough deformation width without causing certain damage, which is the most basic deformation joint function.

1. The characteristics of construction joints and deformation joints are different.

1) Construction joint: construction joint is not a real "joint", it is only because the concrete is poured first more than the initial setting time, and there is a joint surface between the concrete section of the concrete section of the condensation soil that is poured later, and the joint surface is called the construction joint.

2) Deformation joints: Building grip objects often deform under the action of external factors, resulting in cracking and even damage. A deformation joint is a construction joint that is reserved for this situation.

2. Construction joints and deformation joints are referred to differently.

1) Construction joint: It is a joint formed between the concrete poured first and later due to the design requirements or construction needs to be poured in sections in the process of concrete pouring.

2) Deformation joint: It is a general term for expansion joints, settlement joints and shockproof joints.

3. The regulations for construction joints and deformation joints are different.

1) Construction joint: When the concrete needs to be heated and cured, the temperature difference between the newly poured concrete and the adjacent hardened concrete or geotechnical medium shall not be greater than 15 degrees Celsius. The temperature of the foundation surface in contact with the concrete must not be lower than 2 degrees Celsius.

2) Deformation joint: the building structure joint set up to avoid uneven settlement and cracking of the wall or other structural parts when the height of the same building is very different, the upper load is unevenly distributed, or when it is built on different foundation soils.

For more questions, welcome to call for details!

The construction joint in the building refers to the construction joints that can not be carried out continuously during the concrete construction and needs to be poured in sections, and the construction joints left are intermittent, and the construction joints are not really "joints" in the actual sense, it is only because the concrete is poured first more than the initial setting time, and there is a joint surface between the concrete and the mixed macro car concrete that is poured later, and the joint surface is called the construction joint.

The construction deformation joint is a structural joint reserved for this situation in the engineering design, considering that the building will be deformed under the action of external factors such as temperature, settlement, and **, resulting in cracking or damage, and the deformation joint includes expansion joint, settlement joint and shockproof joint.

The construction joint can be left in the deformation joint part, and can also be left in the part where the force is less in the middle of the concrete structural component, and the construction joint that is left in the deformation joint part is the deformation joint at the end, and the construction joint that is left in the middle part of the structural component needs to be completed with concrete handover. Deformation joints need to be left with a gap at the end, which is then filled with other flexible materials and covered by decorative finishes.

The deformation joints of the building are mainly located in the middle of the building.

Building deformation joints are divided into three types according to the different external damage factors, namely expansion joints, settlement joints and shockproof joints.

In industrial and civil buildings, due to the influence of factors such as temperature changes, uneven settlement of the foundation and **, additional stress and deformation will occur inside the building structure, if not properly treated, it will cause damage to the building, produce cracks and even collapse, affecting the use and safety.

The solution is to strengthen the integrity of the building so that it has enough strength and stiffness to overcome these failure stresses without causing damage; In advance, the Sankai structure is disconnected in these deformation-sensitive parts, leaving a certain gap to ensure that each part of the building has sufficient deformation width in these gaps without causing damage to the building. This kind of reserved gap that separates the building vertically is called a deformation joint.

<> deformation joint is a general term for expansion joints, settlement joints and shockproof joints. Buildings are often deformed under the action of external factors, leading to cracking and even destruction. A deformation joint is a construction joint that is reserved for this situation. Deformation joints can be divided into three types: expansion joints, settlement joints, and shockproof joints.

1. Expansion joints: building components will expand and shrink due to changes in temperature and humidity and other factors. For this reason, vertical gaps are usually set up in the appropriate parts of the building, and the walls, floor layers, roofs and other components of the house are disconnected above the foundation, and the building is separated into several parts that stand alone.

Joints set up to overcome excessive temperature differences, the foundation can be disconnected from the top surface of the foundation to the roof along the structure.

2. Earthquake-proof joints: In order to make the building more regular, in order to facilitate the seismic resistance of the structure and set up joints, the foundation can be continuously opened. The purpose of its setting is to divide large buildings into smaller parts to form a relatively independent earthquake-proof unit, so as to avoid damage caused by the uncoordinated overall vibration of the building.

In the seismic fortification area, the settlement joints and expansion joints must meet the requirements of seismic joints.

3. Settlement joint: refers to the building structure joint set up when the height of the same building is very different, the upper load is unevenly distributed, or when it is built on different foundation soils, in order to avoid uneven settlement and cracking of walls or other structural parts. Settlement joints divide the building into several sections, which are self-contained, from the foundation, walls, floor slabs to the roof.

The seam width is generally 70-100 mm.

A vertical joint that completely separates a building or structure from the foundation to the top. In order to avoid the uneven subsidence of each section and the formation of cracks. It is usually set between parts of the building that vary greatly in height, load or foundation capacity, as well as at the junction of the old and new buildings.