305R-99: Hot Weather Concreting

Concrete mixed, transported and placed under conditions of high ambient temperature, low humidity or wind requires an understanding of the effects such environmental factors have on concrete properties and construction operations. When these factors are understood, measures can be taken to eliminate or minimize undesirable effects. The most serious difficulties are experienced in weather and types of construction that are unusual in the experience of those performing the work.

This committee report defines hot weather, lists possible unfavorable effects, and presents practices intended to minimize them. Among these practices are such important measures as pre-cooling ingredients, consideration of concrete temperature as placed length of haul, facilities for handling concrete at the site, and special batching, placing and curing techniques. A selected bibliography is appended. 20 pp.

Table of Contents:

• Introduction
• Effects of hot weather on concrete properties
• Production and delivery
• Placing and curing
• Testing and inspection
• References
• Appendix A--Estimating concrete temperature
• Appendix B--Methods for cooling concrete