Finite Element Analysis of Cob Wallettes Using Etabs

Present study conducted a novel analytical programme to evaluate the compression and shear behaviour of cob wallettes. Earthen material shows environmental advantages when used as building materials. There are several available techniques where these materials are employed with structural purposes, likely as earth blocks (adobe), compressed earth blocks (CEB), cob and rammed earth. Adobe masonry is built with earth block units laid with an earth mortar. The manufacture of adobe masonry usually follows the same principles as those used for fired clay brick masonry. This is the comparative study on the experimental results of rammed earth and cob in compression and shear behaviour of cob wallette’s reinforced with bamboo and steel mesh evaluated and finite element analysis of cob wallette’s using software that is by using Etabs. Earthen wallettes were tested in the laboratories within an experimental program whose goal was to derive the compressive and shear strength of the cob wallette’s reinforced with bamboo and steel mesh. The material characterization and its modelling are hardly predictable due the variability shown by the raw earthen materials. For this reason, a detailed characterization of the earthen materials properties is required when the use of complex constitutive laws is necessary. In addition, considering the aforementioned aspects, the constitutive model, selected referring to the material behaviour and the analysis computational demand, needs to provide a good match between representativeness, complexity, accuracy and reliability. The first part of the study presents the mechanical characterization of earthen materials carried out. Earthen wallettes were tested in the laboratories within an experimental program whose goal was to derive the basic mechanical properties to employ in the numerical simulation. The second part of the study deals with the numerical modelling of the earthen wallettes implemented in FEM software Etab. The aim of the finite element analysis is to simulate the non-linear shear behavior of earthen materials. For adobe masonry the non-linear constitutive laws are based on the multidirectional fixed crack model and combined interface model. The macro-modelling approach was considered for the simulation of the experimental results obtained. Additionally, the micro-modelling approach intended to evaluate the influence of the interfaces between layers on the shear behaviour of rammed earth and failure mechanism block-mortar in adobe masonry.