MOGENS BUHELT Danish Building Research Institute
The combination wall provides an extension of the concept of the cavity wall. A combination wall consists of two structurally active leaves and a layer of insulation material. The inner leaf generally varies in material and thickness from the outer leaf, which typically is based on masonry, but nonetheless their stiffnesses are similar. The leaves are connected by wall ties and thus share the lateral load and the bending moments due to vertical load in proportion to their stiffnesses. The stiffness of a wall leaf, however, is influenced by the vertical load acting on the leaf. A simplified method is presented to take this effect into account which will be implemented in the new Danish code for masonry. In addition, it provides a tool for the determination of deflections and bending moments in laterally loaded columns in general.