Interfacial behavior of cement stabilized rammed earth: Experimental and numerical study

Cement stabilised rammed earth (CSRE) is a modern earth construction technology witnessing renewed interest by researchers worldwide due to its improved strength and durability vis-a-vis un-stabilised rammed earth (URE). Rammed earth walls are predominantly subjected to compressive loading and occasionally to lateral loads. Strength and deformation ability of interface in rammed earth plays a vital role in case of in-plane lateral loads. The present study focuses on assessing the performance of interface layers in cement stabilized rammed earth elements. Triplet test is conducted on CSRE specimens under dry and saturated condition. Three types of bonding techniques are considered for the interface in CSRE triplets, namely, (i) formation of dents (ii) coating cement slurry across interfacial area (iii) combination of dents and slurry. The influence of stresses normal to the interface of CSRE triplet is also explored in this study. Further, a finite element simulation of the CSRE triplet test is performed. A finite element model of the CSRE triplet is developed by using ABAQUS software. Eight node brick elements are adopted to model the CSRE material and interface. Linear elastic material model is adopted for the CSRE material whereas a PPR-potential based cohesive model is adopted for the interface. Shear stress-displacement curve obtained from the finite element model and experiment are compared with each other and were found to be in reasonable agreement.