Site investigation is a process of obtaining the information about subsurface conditions at a site where construction is proposed. It is generally done for big engineering projects. Information gathered from this investigation about subsurface is essential for design of structures and for planning construction techniques.
Site Investigation basically consists of obtaining profile of natural soil, taking soil samples, determining engineering properties etc..
Purposes of Soil Investigation are as follows:
1. Select type and depth of foundation for a structure
2. Determine ground water table and its properties
3. Determine Bearing Capacity of soil
4. Predict Lateral Earth Pressure against retaining walls
5. Investigate the safety of the existing structures and suggest remedial measures
6. Predict and solve potential foundation problems.
Stages of Site Exploration :
1. Reconnaissance : This is the first step in subsurface exploration. It includes visit to site and study the maps and relevant records which help in deciding the future programme of site investigation, scope of work, methods of exploration, types of samples to be collected, laboratory and in-situ testing.
2. Preliminary Exploration : This exploration is done to determine the depth, thickness, composition of soil, bed rock depth and ground water table. Preliminary Exploration is generally done in the form of borings or test pits.
The boundaries of different strata are located using Geophysical methods. The strenght and compressibility of soil is determined using cone penetrometers and sounding rods.
3. Detailed Exploration : This exploration is done to determine engineering properties of soil, which includes an extensive boring programme, sampling and testing of samples in laboratory.
To determine the properties of soil in natural state vane shear test, plate load test and permeability of soils are conducted.
Tags : site investigation, methods of site investigation, site investigation and soil exploration, site investigation stages, site investigation and soil exploration.