Action Effect of Concrete Pavement with different Properties of Top and Bottom Layer due to Moisture and Temperature Variations

摘要

The top layer of two-layer concrete pavement can be produced with either an exposed aggregate finish or as high strength concrete. Recycling aggregate from old concrete pavement is frequently used in the bottom concrete layer. This can lead to large deformations and stresses due to moisture and temperature variations as well as enhanced autogenous shrinkage. A two-layer construction comprising a top layer of high stiffness on a bottom layer of lower stiffness lowers the stresses. In order to avoid high stresses due to annual and daily temperature variations caused by the bimetal strip effect, the difference between the coefficients of thermal expansion should be at most 0.25 centre dot 10~(-5)/K.