Distance Between Expansion Joints In Concrete Retaining Walls

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Distance between expansion joints in concrete retaining walls.

Expansion joints are not permitted in footings except at bridge abutments and where the substructure type changes such as locations where spread footing to pile footing occurs. Also known as control joint kosmatka wilson 2016 expansion joint. 4 recommends a contraction joint spacing of 30 times the wall thickness or 20 feet for an 8 inch thick wall 30 8 240 inches 20 feet. In a concrete structure.

Expansion joints are separated unbonded surfaces used to prevent stress or load transfer from one feature or structure to another adjacent feature or structure bureau of. Generally the spacing of the control joint is specified for a minimum of 20 feet 609 6 cm in the center. Expansion joints are provided to allow th. National concrete masonry association segmental retaining walls sales jump 3 in 2016.

A concrete masonry wall may crack as it shrinks over time. O reclamation a. The friction of the concrete is the key factor that limits the movement. Expansion joints are provided in every large structure which is subjected to high variation in temperature during its lifetime.

Say the calculated distance between the joints is 7 meters and the distance between columns is 7 meters then a calculated risk is taken by placing them at 7 meters. There is a special check to be done at the construction joints when larger retaining walls or structures having very high lateral loads are designed. This temperature variation causes expansion and contraction in the structure. Some designers recommend re ducing joint spacings by about 20 in walls with frequent openings such as doors and windows.

This type of joint is used in concrete or concrete masonry to impart a plane of weakness. Where control joints are provided in such a wall they widen as the concrete masonry shrinks preventing it from cracking. The hight shear force is applied at the horizontal construction joints located at the lower level.