2008 Volume 6 Issue 1 Pages 111-120
This paper proposes a simplified prediction model for drying shrinkage stress in a concrete building wall externally re-strained by beams. This prediction model is a uniaxial model with an effective Young's modulus method based on the following three assumptions: (1) the equilibrium condition of forces between a wall and restraining beams, (2) equal restraining effect between the upper and lower beams, and (3) Bernoulli-Euler hypothesis for the strains in the entire cross-sectional areas of the members.
The accuracy of this model was verified using five types of reinforced concrete walls constructed using three kinds of coarse aggregates, namely, normal coarse aggregate and recycled coarse aggregate of grade 1 and grade 3. The elastic modulus, drying shrinkage strains and creep coefficients of concrete specimens were measured. Furthermore, control concrete walls and beams were also constructed in order to measure the free shrinkage strains of concrete elements. Based on these mechanical properties, the shrinkage stresses in the walls were well simulated by the proposed model.