Seismic behaviour and strengthening of rammed earth constructions

Abstract

The widespread use of earthen buildings can be accredited to the local availability of the raw material, sustainability of the building process, and low cost. Earthen structures suffer from high seismic vulnerability, resulting from the low strength of the material, high mass, and lack of engineering approaches in design and building. Despite the extensive use of rammed earth structures, the structural behaviour of such buildings is still not well known, particularly concerning the in-plane and out-of-plane response under cyclic loads. Moreover, proper strengthening solutions are still required to reduce seismic vulnerability. In this context, an experimental program was conducted on the in-plane and out-of-plane cyclic performance of rammed earth structural sub-assemblies. The prototypes, after being damaged, were strengthened by employing a TRM-based solution and subjected to further testing. The experimental results are reported and discussed in terms of cracking pattern and peak base shear coefficient. Finally, the effectiveness of the proposed strengthening solution was evaluated against the performance of the unstrengthened mockups. The outcomes highlighted the effectiveness of the TRM solution in improving the ductility and the in-plane shear capacity of the mockups.