Influence of particle grading on the hygromechanical properties of hypercompacted earth

Alessia Cuccurullo,Christian La Borderie,Domenico Gallipoli,Paul Hughes,Charles Augarde,Agostino Walter Bruno

doi:10.1007/s41024-019-0066-4

Abstract

Civil engineering research is increasingly focusing on the development of sustainable and energy-efficient building materials. Among these materials, raw (unfired) earth constitutes a promising option for reducing the environmental impact of buildings over their entire service life from construction to demolition. Raw earth has been used since old times but only recently has acquired prominence in mainstream building practice. This is mainly because of the development of novel methods to enhance the mechanical, hygroscopic and durability properties of compacted earth without increasing carbon and energy footprints. In this context, the present paper studies the dependency of the strength, stiffness, moisture capacity and water durability of compacted earth on particle grading. Results indicate that the particle size distribution is a key variable in defining the hygromechanical characteristics of compacted earth. The effect of the particle size distribution on the hygromechanical properties of compacted earth may be as important as that of dry density or stabilisation. This study suggests that a fine and well-graded earth mix exhibits higher levels of strength, stiffness, moisture capacity and water durability than a coarse and poorly-graded one.

Highlights

The construction sector accounts for 30% of the worldwide carbon emissions and consumes more raw materials than any other economic activity on the planet
It is understandable that civil engineering research is currently focusing on the development of resource-effective construction materials that can reduce the environmental impact of buildings during construction, operation and demolition
The utilization of raw earth as a building material is attracting the interest of engineers and architects worldwide due to environmental and economic advantages and to the availability of novel fabrication techniques that can meet the demands of modern construction

Summary

Introduction

The construction sector accounts for 30% of the worldwide carbon emissions and consumes more raw materials than any other economic activity on the planet. Raw (unfired) earth is a attractive construction material that can cut down energy consumption and carbon production over the entire lifetime of buildings, resulting in lower levels of embodied, operational and end-of-life energy [1]. The amount of energy required for the transportation and manufacturing of raw earth is relatively low compared to conventional construction materials. Raw earth exhibits a strong ability to store or release ambient moisture while exchanging latent heat with the surrounding environment. This increases the comfort of occupants and reduces the operational energy required for conditioning indoor temperature and humidity [1, 3, 4].

Methods

Results

Conclusion