Expansion joints, settlement, dividing joint is what defines the various joints Definition: To prevent the building components due to temperature changes, expansion and contraction cracks or damage so houses, separated by a certain distance along the building reserved for vertical slit in the lengthwise direction. This slit due to temperature changes every set is called telescoping. Approach: From the top of the foundation began, the walls, floors, roofs are all turned off so that it is divided into several sections. Joint Distance is about 60m; width 20mm ~ 30 mm. Settlement joint Definition: To prevent the various parts of the building due to the uneven ground subsidence caused by the destruction of the houses set vertical seam called settlement joint. Approach: From the bottom of the base is disconnected, and throughout the whole building height. So that both sides of each as a separate unit, vertically freedom of settlement. Dividing joint broader scope, usually in external plastering need to set sub-lattice seam in the overall construction of the surface layer in order to prevent the temperature of the surface layer as well as construction materials and cracking own factors, it is generally divided according to 4--6 meters surface layer through the seam, which would crack cried dividing joint. General sub-lattice seam width not less than 1.5cm, the depth of not less than 1.5cm (or to structural layer). Suitably delimited area 10m2. Expansion joints and settlement joint set somewhat similar disconnect between them and the two beams with two rows of columns, separated by a 100 ~ 200mm; sub-lattice seam is on a relatively large area, a certain distance from the surface of the plaster The sub-grid, and were filled ointment, common in the roof. Construction joints: the construction process is not easy placement and retention time, the specific location where you want to stay in a smaller force structure at the board to stay in 1/3. Joints: temperature dependent, is to prevent the building due to temperature deformation retention gap. Used for bridges, bridges and cap (or two beams joints) you can find. Settlement joint: When the condition of the building at different addresses (while in weak base) or between tall buildings and podium (mother F) basis from the beginning of the vertical slit lien, between popular point that is not connected to the House floor. After pouring belt: to place concrete structure: temperature, shrinkage cracks and hazardous settings. After pouring the concrete with an intensity higher than the previous cast (if the previous is that the back strip is C30 C35) 1, after pouring belt, the treatment of construction joints: Remove the interface is easy to heal faster networks, concrete cross-section cutting hair and clean, and then 48 hours of the first two parts were pouring concrete watering conservation, and use the same label before pouring grout poured in after pouring belt construction joints or construction joints on both sides, after Concrete with a rating higher than the original micro-expansion were pouring concrete. After reaching the initial setting strength, maintenance required 14 days. 2, back strip, and construction joints Deformation difference after one with a pouring, pouring belt is to prevent harmful crack situ reinforced concrete structure due to temperature, uneven shrinkage may occur, according to the design or construction specifications, In the board (including foundation slab), walls, beams corresponding position leaving in temporary construction joints, the temporary structure is divided into several parts, through the internal components shrink, at some time after the pouring of the concrete construction joints, the structure together into a whole. After pouring belt is an effective measure can solve the differential settlement and reduce shrinkage stress, so many applications in engineering. Position after setting the pouring belt, the distance is determined by design calculations, consider the width of the construction is simple, avoid stress concentration, usually 800 ~ 1200mm; after the water requirements of the site set up pouring belt, you should consider water stop construction; after setting pouring with the site should also consider other measures of different templates consumption factors; after pouring concrete with parts of the micro-expansion, strength grade level to be raised than the original structure. 2, after pouring role with 2.1, solve differential settlement. Design of the structure and foundation of a high-rise building and the overall podium, but after the construction of the two parts by pouring belt temporarily disconnected, the main structure of the construction to be completed, has completed the majority of the settlement amount (50%) after re-watering connection part concrete, the high and low together into a whole. Basis should consider a two-stage design different stress state, respectively strength check. Even as the overall calculation should be considered after the additional internal forces caused by differential settlement late. This approach requires good soil, settlement houses can basically be completed within the period of construction. At the same time you can also take the following adjustments: (1) adjusting the pressure difference. Main load large, the overall infrastructure to reduce soil pressure, and increase the depth, reduce the additional pressure; the lower part is a shallow cross beam foundation, increasing soil pressure, so high and low settlement closer. (2) adjusting the time difference. Construction of the main building first, until basically completed, the settlement is basically stable, construction podium again, so basically similar post-settlement. (3) adjusting the elevation difference. After the settlement terms, the main building was set slightly higher elevation, the podium was slightly lower elevation set aside both the differential settlement, making the final of both the actual elevation consistent. 2.2, reduce the temperature shrinkage. Fresh concrete in the induration process will shrink, the structure has been built to heat expansion, the cold will shrink. Most of the shrinkage of concrete induration in the first 1 to 2 months after the construction is completed, and the effect of temperature changes on the structure is regular. When the deformation is constrained, the internal structure of the generated thermal stress, severe cracks will appear in the component. After pouring in the construction zone located, is in the long building, located every 30 to 40 meters in width from 700 to 1000 mm seam, inside seam using the lap steel curved or straight plus approach. After leaving the band after pouring, the construction process can be free shrinkage of concrete, thus greatly reducing the shrinkage stress. Most of the tensile strength of concrete can be used to resist thermal stress, improve the structural capacity to resist temperature changes. After pouring with retention time is generally less than one month, in the meantime, the shrinkage deformation of 30% to 40% complete. Time after time pouring pouring band should choose low temperatures (but should be a positive temperature), available pouring cement or cement mixed with aluminum powder concrete trace, its intensity level should be higher than the intensity of high-level members, between the old and new concrete to prevent cracks, resulting in weak parts. Deformation 

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