Category: Building Stones

Because of crystallization on reaction with some chemicals, the stones may show a loss of weight and some defects. This test consists of immersing a cubical specimen of 40 mm side in a sodium sulphate solution for 2 hours and then drying it in an oven at 100°C. This procedure is repeated for five times.…

This test is also called Mohs’ scale of hardness test. This is a simple test in which the hardness of the test is based on the hardness of the surface. The surface of the stone is scratched with the help of a pen knife, and the hardness is gauged based on the relative abrasiveness of minerals…

It is a rough test without any rigid specification or procedure. A stone is struck by a hammer to gauge the toughness of the stone. The force required to break the stone reflects the toughness of the stone.

This is usually called the water absorption test. This is a simple test conducted on all stones. It consists of keeping a cubical specimen of the stone of about 50 g weight immersed in water for 24 hours and finding the volume of the absorbed water. This is represented as a percentage of absorption by…

Simple field tests are the absorption test, Smith’s test, the toughness test, the hardness test, the acid test and the crystallization test.

Building stones must be tested to assess their properties to use for various purposes. Some tests are simple which can be conducted in the field, and some can be tested only in a laboratory. Accordingly, they may be grouped as field tests and laboratory tests (IS: 1121, 1974 and IS: 1124, 1998).

Stones have to be selected for a specific work based on the strength and other properties including durability. Stones needed for building exposed to different environments and stones needed for other civil engineering works are discussed below. General Building Works Stones are used for foundations, walls and superstructure. Stones with a high mechanical strength and…

Preservation of stones is intended to protect the structure against the action of weathering agents and also to protect the good appearance of the face work. The durability of stones increases remarkably if the stones are properly preserved. Preservation is effected in the following ways:

Various agencies which are responsible for the deterioration of stones are discussed below. 1. Rain Rain is one among the main causes for wetness on stones. This wetness is dried by the sun. The process of wetting and drying go a long way in deteriorating the stone. Gases and acids contained in rain water may…

Durability of stones depends on the environment at which they are constructed. For proper durability assurance, it is necessary to know the agencies which deteriorate stones and to take adequate steps to preserve the quality of stone during its lifespan.