But rebars have actually ductile property, which allows it to expand and also contract together the temperature increases and also decreases, respectively. This is due to seasonal changes.

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Thus, to stand up to cracks in concrete structures, expansion joints room provided.



protect concrete edge from damages caused by vehicle traffic,act as a seal to prevent international objects/debris indigenous entering the joint opening.allow for expansion and also contraction brought about by heat cycles, andallow because that the organic creep and shrinkage the concrete.


Generally, steel reinforcement is used for the building of bridges and also bridge decks, whereby reinforcement is acting together a tensile load carrying material and used to resist the tensile stress. Generally because of thermal stresses expansion may take place in frameworks which leader to crack if expansion joint is not provided. In this way expansion joint is designed together a safe means to observe the heat-induced expansion and contraction that structures. In timeless systems, the development is of rubber-based and also nowadays that is extremely used in cement concrete road because it can increase when heat increase. Complying with are the two species of development joints provided nowadays

Modular growth jointCantilever expansion joint

The growth joints enable for easy activity of concrete slab edges once the concrete that the deck expands or contracts. Together a result, the expansion joints protect against the the deck slabs from colliding and cracking, stress and anxiety cracking and bending the end of shape.

The growth can be thermal expansion because of seasonal and weather changes and also also, expansion due to traffic load on the slabs. The vehicle axles normally impose asymmetrical moment which cause differential bending at different slab edges. To save the deck in initial shape, development joints play second role.

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Also, usually in concrete pavements, continual shaped cracks or cuts space deliberately introduced just ~ construction, so that the location of future cracks is fixed due to the fact that the concrete is far more liable come crack whereby it’s currently cracked. This cracked area is in turn furthermore reinforced by the growth joint steel and the future cracks room by restricted from spreading. This is the reason why the cracks are made at the edges only.