![]() The contractor claimed the engineer was responsible for slab cracking because his design joint spacing "pushed the limits" of accepted practice. The engineer had such an experience involving slab cracking. If panels do crack, the design may be criticized as unconservative in a claims action. In hot, dry weather or when poor construction practices are used, even 12-foot joint spacings for a 6-inch-thick slab may be excessive. He contends that mid-panel cracking is likely in a 6-inch-thick slab with joints at 18 feet or in a panel with a 1.5 length-to-width ratio. Reader response:Ī consulting engineer called to warn about the dangers of designing joint spacings at the extremes of these limits. Thus, for a 6-inch-thick slab the maximum recommended joint spacing is 18 feet. The recommended joint spacing in feet is usually two to three times the slab thickness in inches. Panels with excessive length-to-width ratios are likely to crack at the mid-panel point or at some other location between joints. This value is recommended in "Guide for Concrete Floor and Slab Construction," ACI 302.1R-80, in Section 2.3.2 on contraction joints. No wire mesh is called for in the 6-inch-thick slab.Ī.: The rule of thumb is that the ratio of panel length to width shouldn't exceed 1.5. Q.: What's the maximum recommended length-to-width ratio for sections between joints in a slab on grade? The drawings for a job I'm building show some bays that are twice as long as they are wide. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |