Structural performance of bamboo 'bahareque' walls under cyclic load

In many Latin American countries, people have traditionally built and still build their houses with 'bamboo bahareque' walls (these walls have a timber frame with split bamboo in the middle, covered with cement plaster on both sides). However, this constructive technique has not been technically studied, which is necessary to validate or, if necessary, improve it as a previous step to a much needed dissemination effort. The objective of the research reported in this paper is (a) to experimentally evaluate the strength and deformation capacities of prefabricated 'bamboo bahareque' shear walls developed in Costa Rica by the Bamboo Foundation (FUNBAMBU), under horizontal cyclic loads simulating earthquake effects, and (b) to propose testing procedures and provide reliable design recommendations for 'bamboo bahareque' house design and construction. For this purpose, 7 full-scale 'bamboo bahareque' walls were built and tested at the Materials and Structural Models National Laboratory (LANAMME), School of Civil Engineering, University of Costa Rica. The dimensions of the walls are 2.4 m in height and 2.7 m in length with a thickness varying from 40 to 60 mm. The results showed that the tested 'bamboo bahareque' walls have enough capacity to withstand earthquake induced loads of considerable magnitude. They also presented some ductile behaviour under cyclic loading.