Flooding Effect on Earth Walls

Gabriela M Medero,Meysam Banimahd,Peter K Woodward,Justin H Kennedy

doi:10.3390/su3010069

Gabriela M Medero, Meysam Banimahd + Show 2 more

Open Access

https://doi.org/10.3390/su3010069

Copy DOI

Abstract

Earth building is a sustainable, environmentally friendly and economical method of construction that has been used worldwide for many centuries. For the past three decades, earth has seen a revival as a building material for a modern construction method due to its benefits in terms of low carbon content, low cost and energy involved during construction, as well as the fact that it is a sustainable technology of building. Climate change is influencing precipitation levels and patterns around the world, and as a consequence, flood risk is increasing rapidly. When flooding occurs, earth buildings are exposed to water by submersion, causing an increase in the degree of saturation of the earth structures and therefore a decrease of the suction between particles. This study investigated the effect of cycles of flooding (consecutive events of flooding followed by dry periods) on earth walls. A series of characterization tests were carried out to obtain the physical and mechanical properties of the studied earth material. In a second stage, Flooding Simulation Tests (FST) were performed to explore the earth walls’ response to repeated flooding events. The results obtained for the tested earth wall/samples with reinforced material (straw) reveal hydraulic hysteresis when wall/samples are subject to cycles of wetting and drying.

Highlights

Earth is still the second most common building material worldwide after bamboo [1], with 40% of the world’s population living in earth buildings [2]
Since the beginning of 1980s, earth as a building material has seen a revival as a modern construction technique [1,5] due to its low carbon content, sustainable method, low cost and energy involved during construction and inherent recyclability [5,6]
A serious enemy of earth construction is water, which can be in the form of moisture ingress [1,7] or by flooding of the earth walls [8]

Summary

Introduction

Earth is still the second most common building material worldwide after bamboo [1], with 40% of the world’s population living in earth buildings [2]. The obtained results show that the addition of straw affects, in terms of compaction, the amount of water that should be added to the mixture to obtain a denser soil structure This information should be considered when mixing the earth materials for construction in the field. The results obtained for the maximum unconfined compression strength were smaller than those usually observed on dry rammed earth and cob due to the fact that the wall/samples were tested with a moisture content of around 7.8% as well as due to the small scale of the specimens. The authors decided to test the samples with the water content of the molding process because this is the most critical situation and the site that motivated the study (in Perthshire, Scotland), presented a high level of relative humidity

Experimental Section

Findings

Conclusions