Spacing Of Construction Joints In Concrete Walls

Chapter 10 mass concrete p.

Spacing of construction joints in concrete walls.

Construction joints use construction joints when the c o n c r ete placement cannot be done at one time. A complete or monolithic con s t r uction joint. It is best to cut joints as early as possible either while finishing with a concrete groover or within 6 18 hours after finishing with a concrete saw. While these attributes are the primary basis for concrete masonry s.

Construction joints are placed in a concrete slab to define the extent of the individual placements generally in conformity with a predetermined joint layout. For example in the construction of a concrete wall we cannot avoid construction joint just above the base. Concrete joints are used to compensate when concrete expands or shrinks with changes in temperature. Unplanned joints also occur on many jobs when equipment bre a k s down or concrete supply is interru p t ed.

Providing construction joint in concrete limits the area to be concreted in a one pour. Construction joints must be designed in order to allow displacements between both sides of the slab but at the same time they have to transfer flexural stresses produced in the slab by. Let s discuss the advantage of construction joints in concrete structures. Concrete joints are normally used to prevent cracks when the concrete shrinks by creating forming tooling sawing and placing joint formers.

An information series from the national authority on concrete masonry technology ncma tek 10 2c 1 control joints for concrete masonry walls empirical method introduction concrete masonry is a popular construction material because its inherent attributes satisfy the diverse needs of both exterior and interior walls. Joint spacing in meters. 9 1 introduction 9 2 contraction joints 9 3 isolation or expansion joints 9 4 construction joints. Joint spacing in feet contraction joints may be tooled into the concrete surface at the time of placement.

Joint spacing that is greater than 15 feet require the use of load transfer devices dowels or diamond plates. Plan out your control joint spacing 24 36 times the depth of your concrete slab. Chapter 9 liquid retaining structures p. Residential basement walls usually are placed without con s t r uction joints.

Thus for a 10 foot high wall control joints should be. 8 2 types of joints in concrete walls 8 3 contraction joints 8 4 isolation or expansion joints 8 5 construction joints. The pre planned cracks will provide a better finish concrete product and will be formed in specific locations where those cracks could be monitored.