Suryakanta The bentonite powder and bentonite suspension used for pilling work shall satisfy the following requirements: The liquid limit of bentonite when tested in accordance with IS 2720 (Part 5) shall be 400 percent or more. The bentonite suspension shall be made by mixing it with fresh water using a pump for circulation. The density of … Read more
Blow counts are affected by operational procedures, by the presence of gravel, or cementation. They do not reflect fractures or slickensides in clay, which may be very important to strength characteristics. The standard penetration test results (N values) are influenced by operational procedures as given in the following table. No. Procedure Its Affect 1. Inadequate … Read more
Even though plate load tests are very commonly used, they do not represent the behavior of prototype foundations totally for the following reasons: The zone of influence for prototype foundation is larger and deeper than for small size plate. Thus, in stratified soil deposits the soils at greater depths will have a significant influence on … Read more
There are many pitfalls associated with the standard penetration test. If these are not carefully avoided, the N-values collected from SPT are mere numbers rather than being useful indicators of soil parameters. Some of the precautions to be taken are: Results of standard penetration test are not reproducible in cohesion less soil below water level … Read more
Reference IS-10050-1981-Method for determination of slake durability index of rocks. Objective This test is done to find out the resistance offered by a rock sample to weakening and disintegration when subjected to two standard cycles of drying and wetting in a slaking fluid usually water. Apparatus used NAME OF EQUIPMENT CAPACITY LEAST COUNT/ACCURACY Balance As … Read more
Reference IS-13030-1991- Method of test for laboratory determination of water content, porosity, density and related properties of rock material. Objective Determination of mass of water contained in a rock sample. Apparatus used Name of equipment Capacity Least count/Accuracy Oven 105±30C 10C Balance As per requirement 0.01% of the sample Procedure Clean the container and … Read more
Reference IS-9143-1979-Method for the determination of unconfined compressive strength of rock materials Objective The objective of this test is to determine unconfined compressive strength of rock. This test is primarily done to classify the rock on the basis of strength. Apparatus used Name of equipment Capacity Least count/Accuracy Loading Machine 5000 kN 2.5 N Vernier … Read more
Objective For determination of free swell index of soils Reference Standard IS: 2720(Part 40)-1985- Methods of test for soils: Determination of free swell index of soil. Equipment / Apparatus Oven(1050C to 1100C, min) Balance (0.01g accuracy) Sieve [425 micron] Graduated glass cylinder [100ml capacity] Preparation sample The soil passing 425 micron sieve is used in … Read more
Objective For determination of linear shrinkage of soil Reference Standard IS: 2720(Part 20)-1966- Methods of test for soils: Determination of linear shrinkage. Equipment / Apparatus Mould Oven Preparation sample A sample weighing 150g from thoroughly mixed portion of bulk material passing 425 micron IS sieve is prepared. Procedure The mould is thoroughly cleaned and a … Read more
Objective Determination of CBR of soil either in undisturbed or Remoulded condition Reference Standards IS: 2720(Part 16)-1973- Methods of test for soils: Laboratory determination of CBR. Equipments / Apparatus Compression machine Proving ring, Dial gauge, Timer Sampling tube Split mould Vernier caliper, Balance Preparation sample The test may be performed (a) On undisturbed soil specimen … Read more