Clay in construction technology

Abstract

Construction projects encounter often problems which are concerned with the characteristic of clay minerals. In one way, clays bring difficulties into construction, and in another, they can be utilized favorably.
The knowledge of clay science is necessary not only for survey, design, material, site work and maintenance of construction projects, but also for conservation of environment, prevention of disaster and disposal of waste products. As clay specialists are few in the construction field of Japan, co-operation and understanding of various clay scientists are needed in the field. As the problems of soil mechanics field, the present paper deals with the relation between soil characteristics and mineralogical structures of clays as well as the relation between soil stabilization and chemistry of clays. As the problems of concrete field, the paper handles harmful clays in aggregates, useful clays for pozzolanic action and for raw material of light weight aggregates as well as the structural similiarity between hydration products of cement and clay minerals. As the problems of disaster prevention, the paper refers to land slide, swelling and deformation of tunnel as well as settlement of ground. Further, the paper touches upon solidification of waste products and very soft alluvium soils, oxygen deficiency in underground work sites, and silicosis due to clay materials.