Belling Stress In Rigid Pavement Slabs In The Environmental Conditions Of Portoviejo

Abstract

Temperature changes during the day cause thermal gradients between the upper and lower parts of the concrete slabs, generating warping stresses. Based on a previous investigation, carried out in Portoviejo, Ecuador, in which a simple concrete slab with a joint was instrumented, in this work a mathematical model is obtained that relates the ambient temperature with the temperature of the slab at different depths, in the climatic conditions of this city. Using this model, the temperature gradients in the slab were determined in each month of the year, to consequently estimate the warping stresses, using the EverFE Finite Element software. A maximum expected gradient is presented in the month of April, equal to 11.8OC, with maximum traction values for the interior and edges of the slab, of 1.52 MPa and 1.34 MPa, respectively.  It has been proven that the warping stresses in simple concrete slabs, for slab lengths of up to 4.50 meters, do not represent a significant effect for the fatigue consumption of the concrete, because the stress ratio between the maximum tensile value in the edges and the Modulus of Rupture of the concrete does not exceed 30%, in addition to having a very low probability of occurrence.