INSTRUCTIONS ISSUED BY THE BUILDING CODE FOR CONSTRUCTION SHOULD BE FOLLOWED FOR REMEDIAL MEASURES SUGGESTED BY THE ENGINEERING DEPARTMENT, FOR THE SAFETY OF EXISTING STRUCTURES .

CAUSES OF FAILURE OF FOUNDATIONS :-- (2) Unequal settlement of the sub -soil for which masonry should be raised uniformly over the whole area .A slow progress of masonry work makes stronger joints and has more uniform settlement.(2) Unequal distribution of the weight of the structure on the foundations due to eccentricity of loads .In continues wall reinforcement should be provided whenever an abrupt change in magnitude of load or variation in ground support may occur.(3) Horizontal movement of earth adjoining the structure.This is effective in case of clayey soils and black cotton soils.Such soils becomes soft and swell when wet losing their bearing power considerably and shrink and crack when dry .(4) Atmospheric action :- Rain and the sun are the main agents with the change of seasons .Rise and fall of the sub soil water level , increasing or decreasing the moisture content which is especially effective when the underground water is near the surface,or in damp soils overlying a layer of porous material like sand , the sub soil shrinks or expands causing cracks .A plinth protection of about 60 to 90 cm width with concrete must be provided for the safety measures (5) Transpiration of trees and shrubs is a very important factor which is not generally considered.The drying effects of the transpiration of trees and shrubs are superimposed on the seasonal conditions and whenever the roots approaches the founded structures ,the root system of the isolated trees generally spread to a radius greater than the height of the tree and have been observed to cause significant drying of fat clay soil to a depth of three metres .The fast growing trees are especially dangerous.Some times a permanent depression of the ground is produced during the early period of the rapid growth ,when the tree demands more water than is available on the ground.It has been suggested that the fast growing and the water seeking trees should not be planted minimum twenty feet with in the building area .