Mechanical properties of hardened concrete in hot and dry climate

Concrete is the most popular material in construction industry. Recycling of waste and their application in the construction industry are the main purpose in the world economy. The concrete working in dry and hot climate are exposed to high temperatures in the summer. The temperature can increase up to 50 °C while the relative humidity drops to 10-15% and lower. Climatic conditions lead to decrease the performance properties (strength and modulus of elasticity). The basic tasks of region with dry and hot climate are improve resistance and efficiency of concrete. An extreme daily change in temperature, low humidity, soil salinity are the main cause of erosion of concrete. One of the way of optimizing of cracking resistance of the concrete is to increase the amount of cementitious components. The dependencies of experiment with similar climatic conditions based on sulfate resistant cement were conducted. The results of experiment show that the optimal content of materials in concrete included 530 kg of cement; 833 kg of quartz sand; 873 kg of coarse aggregate; 1.5 liters of plasticizer and 176 liters of water. The designed mixture had the following characteristics: the density 2414 kg/m3, the compressive strength in 28-day at the range of 47 MPa, water permeability - W4, with water cement ratio equal to 0.34. (paper)