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Waterstop for concrete structures

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Large structures are usually poured in different stages. It is not possible to cast large structures at one time. The casting of large structures at one time will require a long time, a huge number of workers and equipment. In some cases, the geometric and sequence of work will require the casting of a structure in several stages. Pouring of concrete will result in forming construction joints between different concrete pours. Water-stop is usually used for various structures such as dams, water treatment facilities, storage tanks, culvert, slab on grade, and parking garage. The use of water-stop for storage tanks is critical. Water-stop will prevent the liquid from leaking. So, in general, water-stop will be used for structures that in direct contact with water. Water-stop will prevent the seepage of water from the construction joint. We have two types of water-stop. External water-stop fixed on the wet side of a concrete structure, as shown in figure no:2. External water-stop will prevent the ingress of mud and any other substances. 

Figure no:1


Figure no:2


The second type is internal water-stop. The internal water-stop will be fixed in the center of a concrete member. It will seal the member and prevent the passage of water through the joint. There are various types of internal water-stop. Ribbed flat and dumbbell water-stop used to seal the structures with no or little expected movement. Ribbed and flat with center bulb water-stop are another type of water-stop. These types of water-stop will be used for joints with expected movement. The center-bulb will accommodate the lateral and transverse movement. Aside from accommodating movement, these types of water-stop will prevent the passage of water as in other types of water-stop. 

Figure no:3



Figure no:4


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