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BUILDING STONES

INTRODUCTION

• Building stones used for

stone masonry has high

strength, more durability

and good weather

resisting qualities.

CLASSIFICATION OF STONES

GRANITE SANDSTONE SLATE

BASALT AND TRAP LIMESTONE MARBLE

GRANITE

• Granite is a common variety of igneous rocks.

• It is hard, tough and is found in variety of colors.

• It is used as large building blocks for heavy engineering works such as piers, abutments of bridges, etc.

• It is used or constructing steps, sills and columns.

BASALT AND TRAP

• These are hard and tough and are greenish grey to dark grey in color.

• They are more suitable as road metal, railway ballast and as an aggregate in concrete.

• They are also used as flag stones for paving streets and for constructing steps.

SANDSTONE

• Sandstone is a common variety of sedimentary rocks.

• Its compact and fine grained variety is used in ashlars masonry and other works of architectural appearance.

• It is also used in heavy engineering works such as monumental buildings, dams, docks, etc.

LIMESTONE

• Limestone are the common variety of sedimentary rocks.

• These are unsuited for external work in industrial towns.

• It is used in masonry walls and paving streets.

SLATE

• Slate is a common variety of metamorphic rocks.

• It is hard, tough and least absorptive and gives ringing sound when struck with a light hammer.

• Being absorbent it is also used in bath, cisterns, urinal partitions, etc.

MARBLE

• Marble is compact and crystalline in structure due to which it takes a fine polish.

• It is less durable and its absorption is 1 to 3%.

• It is mainly used for ornamental and highly specialized building works as in columns, staircases, table slabs, window sill, floor finishing, steps, etc.

THANK YOU

By: Nisha ParwaniB.Sc. ID, 2nd sem