Effectiveness of Different Solutions to Reduce Plastic Shrinkage in Hot Climate Concreting Bella Nabil 1 , Assroun Aissa 2 , and Bella Ilham Aguida 2 1 Institute of civil engineering, University of Bechar, B P 417 Bechar 08000 Algeria. 2 Faculty of engineering, Djillali Liabès University, BP 89 Sidi Bel Abbès, 22000 Algeria. E-mail: < bella5dz@yahoo.fr > , < a_asroun@yahoo.fr > , < gini2007@yahoo.fr >. ABSTRACT Hot climate concreting requires that some practices are used to reduce the undesirable effects caused by excessive water evaporation from the concrete surface, which tends to induce plastic shrinkage cracking and thereby reduce durability. This research highlights the effectiveness of different solutions to reduce plastic shrinkage: curing agent, cold water and cover with plastic sheet. Two levels fractional factorial array experimental design was used to reduce the number of tests, and allowed studying both the effect of different factors and interaction between factors. The measured parameters include: plastic shrinkage crack in 10 x 10 x 40 cm specimens, and compressive strength and rate of evaporation. A climatic chamber was used to simulate the hot climate. The results indicate that to minimize the plastic shrinkage the most adequate solution is the application of curing compound followed by the use of a plastic sheet cover. The most effective solution to decrease the evaporation is a plastic film sheet cover. INTRODUCTION Hot climate concreting is when the concrete is mixed, placed and cured at any combination of the following conditions: high ambient temperature, high concrete temperature, low relative humidity, wind velocity and solar radiation. The potential problems for concrete in the freshly mixed concrete state are: increased water demand, increased rate of slump loss corresponding tendency to add water at the jobsite, increased rate of setting (resulting in greater difficulty with handling, compacting finishing and a greater risk of cold joints), increased tendency for plastic shrinkage cracking and increased difficulty in controlling entrained air control. The potential problems for concrete in the hardened state may include: decreased 28-day and later strengths resulting from either water demand and/or higher concrete temperature, decreased durability resulting from cracking, increased potential for reinforcing steel corrosion (this is primary due to increased cracking) and increased permeability [Adam 2000; ACI 305]. On the other hand, fiber- reinforcement virtually eliminates plastic cracking. Plastic cracking can be effectively controlled by protecting the fresh concrete from drying as early as possible, but always before its surface Coventry University and The University of Wisconsin Milwaukee Centre for Byproducts Utilization, Second International Conference on Sustainable Construction Materials and Technologies June 28  June 30, 2010, Università Politecnica delle Marche, Ancona, Italy. Main Proceedings ed. J Zachar, P Claisse, T R Naik, E Ganjian. ISBN 9781450714907 http://www.claisse.info/Proceedings.htm