After cracking, it becomes active and controls crack widths by restricting crack growth. Reinforcement is basically dormant until the concrete cracks. Steel reinforcing bars and welded wire reinforcement will not prevent cracking. Unrestricted crack width growth leads to spalled edges along out-of-joint cracks when exposed to wheeled traffic, especially hard-wheeled lift trucks. While there are several reinforcing options for nonstructural slabs-on-ground, this article focuses on steel reinforcing bars and welded wire reinforcement for crack width control. Because of constructability issues and costs associated with two layers of reinforcement, structural slabs-on-ground are not as common as nonstructural slabs. Most structural slabs-on-ground have both top and bottom layers of reinforcement for controlling crack-widths and increasing load capacities. Structural reinforcement is typically placed in the bottom portion of the slab thickness to increase the slab's load capacity. Shrinkage and temperature reinforcement is different than structural reinforcement. This type of reinforcement is commonly called shrinkage and temperature reinforcement. When positioned in the upper or top portion of the slab thickness, steel reinforcement limits the widths of random cracks that may occur because of concrete shrinkage and temperature restraints, subbase settlement, applied loads or other issues. Most slabs-on-ground are unreinforced or nominally reinforced for crack-width control.
0 Comments
Leave a Reply. |