Behavior of hollow clay brick masonry walls during fire. Part 2: 3D finite element modeling and spalling assessment

•Thermo-elastic nonlinear model is adopted to simulate the fire behavior of walls.•Heat propagation is modeled by three modes (conduction, convection and radiation).•A criterion of type “crushing-detachment-buckling” is used to simulate the spalling.•Scenario of spalling is satisfactorily described.

In the first part of this work [1], the fire behavior of masonry walls made with hollow fired-clay bricks was investigated experimentally. Several complex mechanisms occurred during firing are analyzed and identified. In particular, in cases of load-bearing walls, the local spalling of bricks is considered as an important factor governing the fire performance of masonry walls.In this second part, fired-clay masonry is investigated by theoretical approach with the finite element method in order to predict its behavior and its performance under fire exposure. For this purpose, a 3D numerical simulation is conducted with paying a particular attention to the spalling risks of alveolus bricks.