Compressive and shear behavior of cement stabilized rammed earth wallettes reinforced with coir, bamboo splints and steel bars

This paper investigates the effect of coir, bamboo and steel reinforcement on the axial and diagonal compressive strength of cement stabilized rammed earth wallettes. Two types of rammed earth wallettes were cast (rectangular and square) to study the failure pattern and effect of different height to thickness ratios on axial compressive strength. Rectangular sample type was tested only under axial compression whereas square sample type was tested under axial as well as diagonal compression. 10% cement stabilizer and 1% coir of 25 mm length were used throughout the experimental program. Experimental results reveal that addition of coir improved the compressive strength of samples by about 17.93% - 37.82% and also enhanced the failure mechanism from sudden/brittle to a gradual ductile failure. The strength of rectangular samples decreases by about 4.95% 6.52% and deformation increases by 19.52% - 26.46% respectively when compared with square samples. The maximum compressive and shear strength was recorded with cement stabilized 4-steel coir reinforced rammed earth (CS4SCRRE) samples and the maximum deformation was observed with cement stabilized 4-bamboo coir reinforced rammed earth (CS4BCRRE) samples. Prediction model has been developed and validated with respect to theoretical and experimental values. Strong correlations exist between the predicted and experimental values and found suitable for predicting compressive strength and deformation of wallettes.

Automated summary

This research investigates the effect of coir, bamboo and steel reinforcement on the compressive strength of cement stabilized rammed earth wallettes. The experimental results show that the addition of coir significantly improves the compressive strength of the samples and changes the failure mechanism from brittle to ductile. The study also found that rectangular samples have lower strength and higher deformation compared to square samples.