Geosynthetics for Ground Improvement Long ago, when difficult sites for construction purposes were to be dealt, the conventional practice was limited to either the replacement of unsuitable soils or adopting suitable foundation which sometimes increases the cost of foundations. Innovative soil modification approaches are evolved to solve soil related problems. One among them is the … Read more
Bearing Capacity Definitions Bearing capacity is the power of foundation soil to hold the forces from the superstructure without undergoing shear failure or excessive settlement. Foundation soil is that portion of ground which is subjected to additional stresses when foundation and superstructure are constructed on the ground. The term bearing capacity qualitatively refers to the … Read more
Electrical Resistivity Test of Soil This method depends on differences in the electrical resistance of different soil (and rock) types. The flow of current through a soil is mainly due to electrolytic action and therefore depends on the concentration of dissolved salts in the pores. The mineral particles of soil are poor conductors of current. … Read more
Pile Load Capacity Calculation Using Static Cone Penetration (SCPT) Test Data The safe load capacity of bored cast in situ piles can be calculated using the test data obtained from static cone penetration test as described below. We know that the ultimate load capacity of pile consist of two terms, i.e. End bearing resistance Skin … Read more
Pile Load Capacity Calculation in Weathered or Soft Rock This method of calculating pile load capacity was suggested by Cole & Stroud. Cole & Stroud used ‘N’ values or results of standard penetration tests to find allowable load capacity of the pile in weathered rocks. The formula suggested by Cole & Stroud is given below. … Read more
Guidelines to Follow While Constructing Pile under Water While placing concrete by tremie method, all tremie pipes should be cleaned before and after use. The diameter of tremie pipe should be preferably 200 mm for constructing piles of all diameters within 600 mm. For 25 mm down aggregate, tremie pipe should have a diameter not … Read more
Pile Load Capacity Calculation Using Standard Penetration Resistance This method of calculating pile load capacity in cohesion less soil (i.e. in sand) was suggested by Meyerhof. Meyerhof suggested the following equation, to calculate the ultimate pile load capacity in saturated sand, using standard penetration resistance (N). In the formula given below the 1st term gives … Read more
Step-by-Step Procedure for Calculation of Bearing Capacity from Standard Penetration Test Values or N-values Step-1 Perform standard penetration test on the location for which you want to calculate bearing capacity. This is done as per standard procedure given in IS-2131. Standard penetration test must be done at every 75 cm in vertical direction. Step-2 Decide … Read more
Objective To perform plate load test to obtain a load-settlement curve of a soil at a particular depth so as to estimate the ultimate bearing capacity a foundation. Apparatus Test plate of square size (300 mm or 450 mm or 600 mm or 750 mm) Hydraulic jack (50 T capacity) Hydraulic pump (50 T capacity) … Read more
The ultimate bearing capacity of a pile is the maximum load which it can carry without failure or excessive settlement of the ground. The bearing capacity of a pile depends primarily on 3 factors as given below, Type of soil through which pile is embedded Method of pile installation Pile dimension (cross section & length … Read more