Soil exploration and Site Investigation

 These are the important parameters that should be required from soil investigation report. 

• Soil Identification of the site by boring test
• Location of the ground water table
• Allowable bearing Capacity for foundation design
• soil classification for seismic parameter
• Soil properties to be used in the evaluation of soil pressure, soil settlement, and to determine also if the soil is expansive soil or liquifiable.  

There 3 Steps of Soil Exploration

• Boring =drilling a hole in the ground
• sampling =refers to removing of soil from the hole to obtain valuable information and properties of the soil.
• Testing = refers to determining the characteristics and properties of the soil.

Common Types of borings

Auger boring = by using like tool used to bore a hole by hand operation or power operated. This type of boring is difficult to be operated on very soft clay or coarse due to the hole tends to refill when the auger is removed.

Test Pits = excavating the soil that permits a direct visual inspection of the soil along the sides of the pit. test pits are limited to depth of 10ft to 15ft where water table are expected below this depth.

Core Boring = is usually done when drilling through rock formation.

Common Types of Foundation

 Foundations play vital part in the building; it will support the superstructure from differential settlement and helps to stabilize the structure from tilting.

These are types of footings that are theoretically applied on the building foundations. 

1. Wall footing or Strip Footing

is a continuous strip of concrete that supports non-loadbearing and load bearing wall, stair footing and retaining wall.

2. Square footings 

  are concrete pads that support and distribute the column load directly to an area of soil below the   column.

3. Rectangular Footings

are used to support loads on a single column where the location of the footing is limited to its    property line on one of the sides.

4. Combined footings

    

are used to support two loaded columns. if the support of the two columns are single footings, the        concrete pad would run into each other, so the appropriate support to use is rectangular or trapezoidal footings.

5. Cantilever Footing

   

is usually used when the location of the column is at the edge of the property line, this footing            will require size of concrete pad due to the eccentricity of the load.

6. Strap footings

are to two footings joined by a strap beam. It is usually seen when one of the footings is located at the edge of the property line and the other footing is located at the interior part of the building. 

7. Mat or Raft Foundation

 is single thick slab that supports the entire structure. This type of foundation is usually used with poor soil conditions to control differential settlement.

8. Pile Caps

 is reinforced concrete pad used to distribute column loads to group of piles.