Title:
Contraction Joints in Residential Slabs-On-Ground—TechNote (ACI PRC-224.5-22)
Author(s):
Publication:
Concrete International
Volume:
48
Issue:
7
Appears on pages(s):
55-61
Keywords:
Thermal cracks, shrinkage cracks, contraction joints, PT slabs
DOI:
10.14359/51751812
Date:
7/1/2026
Abstract:
ACI 332 requires contraction joints in plain and reinforced concrete slabs-on-ground. For post-tensioned (PT) residential slabs-on- ground, PTI DC10.1 permits contraction joints to minimize and conceal random cracks. The layout of contraction joints in residential slabs requires special considerations, which are discussed in this TechNote.
Related References:
ACI 224.4R-13—Guide to Design Detailing to Mitigate Cracking
ACI 332-20—Code Requirements for Residential Concrete and Commentary
ACI 360R-10—Guide to Design of Slabs-on-Ground
PTI DC10.1-08—Design of Post-Tensioned Slabs-on-Ground
Bondy, K. B., 1995, “Cracking in Ground-Supported Post-Tensioned Slabs on Expansive Soils,” Technical Note #6, Post-Tensioned Institute, Farmington Hills, MI, 6 pp.
Haynes, H. and Bondy, K.B., 2020, “Contraction Joints for Residential Post-Tensioned Slabs,” Concrete International, V. 42, No. 7, July, pp. 33-35.