Role of Post-tensioned Coconut-fibre Ropes in Mortar-free Interlocking Concrete Construction During Seismic Loadings

This paper mainly presents the experimental work on studying the effect of post-tensioned coconut-fibre ropes in controlling uplifts of interlocking blocks in mortar-free concrete construction during seismic loadings. Interlocking blocks are capable of returning back to their original positions after the ground motion because of provided inclined key between the blocks. Coconut fibre reinforced concrete was used to make interlocking blocks. To simulate a single degree-of-freedom system, a mass of 200 kg is attached at the column top. The seismic response of structure is measured in terms of induced accelerations, block uplift, top relative displacement and rope tension. Generally, induced acceleration is increased up to the column mid-height and then decreased a little bit at the column top. The trends of block uplift and rope tension are somewhat similar i.e. non-linear with respect to the applied incremental seismic loadings. Empirical relations, as a function of peak ground acceleration, are also developed from the experimental results to envisage the structure seismic response. There is a percentage difference up to 35% in predicting the structure response which can be attributed towards the complicated nature of the structure versus the simple approach developed. But still, this can help in understanding the behaviour of mortar-free interlocking structure having post-tensioned coconut-fibre rope in a systematic manner.