Creep Behaviour of Brickwork: A Parametric Investigation

The prediction of the creep behavior of periodic brickwork subjected to in-plane loads is dealt with in this paper. Analytical approximate expressions for the macroscopic relaxation and creep coefficients are proposed, according to simple statically or kinematically admissible solutions in which the joint thickness is neglected, units are assumed to be either rigid or elastic, and creep phenomena are confined in the interfaces between units. A parametric analysis is carried out to investigate the effect of several parameters on the global and local creep behavior of brickwork, namely: i) mortar to-brick thickness ratio; ii) ratio of the mortar Young’s modulus to the brick Young’s modulus; iii) brickwork texture (running vs header bond). A finite element model of a single representative volume element (RVE) is also analyzed under sustained macroscopic stresses, to numerically evaluate the creep coefficients and assess the accuracy of the analytical estimates. The creep coefficients are found to be very sensitive to the block stiffness for thin joints. Also, the agreement between numerical and analytical predictions is better for thicker mortar joints