The Construction Industry

CHAPTER 1

INTRODUCTION

1.1 MASONRY

Construction industry is booming and resource generating field. Construction activities have a significant impact on the environment throughout the life cycle of development. Development of the construction project inherently contributes to the economic and social development and enhancing both the standard of living and quality of life. Construction industry is one of the largest consumers of both renewable and non-renewable natural resources. The materials selected for construction determines the level of environmental impact. The increasing complexity in the construction creates the need for professional designs trained in all phases and develops an admiration of the building as an advanced technological

Availability of experimental results regarding masonry is several but theoretical research to understand the behaviour of masonry is minimal. Masonry units are the individual units, which are combined together with the help of mortar to configure masonry element such as wall, columns, domes, piers and buttress. Conventional materials in load bearing structural masonry such as bricks have become costly, delinquent to depletion in resources and escalating energy cost for burning. Concrete blocks are substituting bricks for masonry

For the distribution of stresses in masonry construction, mortar is the important material. The mechanical and physical behaviour of mortars are affected by the water-cement ratio and grading of the aggregates. A mortar, which sticks the masonry unit together, acts as a sealant and performs as gap filling adhesive. The mortar directly affects the bonding characteristics and performance of masonry. Mortar influences the durability, strength and resistance to water penetration to masonry. Mortars can be categorized into various types depending on the cementitious material such as lime mortar, cement mortar, composite mortar, lime-pozzolana mortar and soil-cement mortar.

Mortars were basically made of clay and mud. The first evidence of humans of using mortar was at the ziggurat of Sialk at Iran in 2900 BC, according to Roman Ghirshman. In the periods of Egypt, gypsum mortar was used for the construction. During the middle ages, lime mortar was the active ingredient, but the structures got degraded from wind. The use of sand and clay was observed in Catal Huyuk in