Finite Element Model Analysis of Thermal Stresses of Thick Airport Concrete Pavement Slabs

Abstract

Thermal stress caused by temperature distribution in pavement slab is important in the structural design of airport concrete pavements. Airport concrete pavement slab is thick; therefore, temperature in the slab varies nonlinearly throughout its depth. Thermal stress caused by nonlinear temperature distribution differs from that of linear temperature distribution. In this study, thermal stress caused by nonlinear temperature distribution was calculated by using temperatures and restraint strains measured in an experimental concrete pavement with 460-mm-thick slabs. The calculated thermal stress differed from curling stress because of the linear temperature distribution. Temperature distributions in concrete slabs of various thicknesses were computed by solving the heat transfer equation with the control volume method. This calculation revealed that temperature distributions in thick concrete slabs were highly nonlinear. Thermal stress was analyzed to compute the nonlinear thermal stress distributions in concrete slabs from the computed temperature distributions by using a three-dimensional finite element model. On the basis of the analysis, effects of slab thickness and nonlinear temperature distribution on thermal stress were discussed. The effect of nonlinearity was found to be pronounced at a slab thickness greater than 300 mm. In this range, the reduction factor for taking into account the effect of nonlinear distribution was larger than 0.7. It was also found that thermal stresses in summer and spring were relatively large.

Thermal Stress Calculation Method for Concrete Pavement Based on Temperature Prediction and Finite Element Method Analysis

“…Values for f σ T are obtained from 3DFEM simulations that use the temperature profiles estimated from one-dimensional heat transfer analysis. The control volume method (CVM) was employed to solve the one-dimensional heat transfer problem of pavements, with climate data obtained from the Automated Meteorological Data Acquisition System (AMeDAS, the Japanese metrological monitoring system) (9). Temperatures predicted with CVM and AMeDAS data for several cities in Japan were compared with those measured at the cities to validate the method.…”

“…These studies have shown the advantages of three-dimensional FEM (3DFEM) analysis for calculating thermal stress due to the nonlinear temperature profile, with considerations of slab configuration, base course stiffness, and load transfer at joints. For thick airport concrete pavements, 3DFEM models that take into account the nonlinear temperature profile have been developed, and their validity has been verified (8,9).…”

Mechanical Behavior of Concrete Pavement considering Void beneath Slabs and Joints LTE

“…A boundary condition of the fixed placement in the horizontal direction is applied to the base course. All displacements at nodes on every side face of concrete slabs are free [36].…”

Technical and Economic Sustainability of Concrete Pavements

“…The thermal pattern of road concrete pavements generates stresses comparable to stresses related to traffic loads (Chai et al, 2012;Qin & Hiller, 2011;Nishizawa et al, 2009;Faraggi et al, 1987), so in the program has been implemented an innovative verified thermal model to describe temperature in slab thickness and calculate thermal stresses.…”