Tests of reinforced concrete floor slab with initial crack

Abstract

This study presents the results of the examination of precast reinforced concrete floor slab with initial crack of continuous rectangular cross-section with nominal dimensions 6380*3230 mm and a height of 160 mm. The slab was manufactured in the factory during summer. Concrete curing took place in natural conditions without the use of heat and humidity treatment. The slab has an initial crack that appeared before the test, located in the middle of the span in the direction of the channel-former in the layer of concrete with minimum thickness. Information on the testing procedure is presented, the results of calculations and full-scale tests are given. The analysis of the slab deformation dependence diagram on the load value is carried out. The conformity of crack resistance, stiffness and load-carrying capacity of a slab with an initial crack to the normative requirements has been checked, and the theoretical and experimental results have been compared. The influence of the initial crack in the slab on its stiffness and crack resistance has been established.