BULKING OF FINE AGGREGATE – WHAT, WHY & HOW?

percentage of bulking of sand with moisture content

The volume increase of fine aggregate due to presence of moisture content is known as bulking. Fine sand bulks more as compared to coarse sand. Extremely fine sand particularly the manufactured fine aggregate bulks as much as about 40%. Note: Fine aggregate do not show any bulking when it is absolutely dry or completely saturated. … Read more

CORRECTION APPLIED TO SPT VALUE

The N-value observed during testing is not utilized directly in assessing soil properties. These values are corrected to account for The overburden pressure Dilatancy in saturated fine sands and silts Correction for overburden pressure The penetration resistance of soil depends on the over burden pressure. At deeper depth in-situ soil will have higher overburden pressure … Read more

COMPRESSIVE STRENGTH TEST OF CONCRETE (IS:516-1959)

Compressive Strength Test on Concrete

Objective The tests are required to determine the strength of concrete and therefore its suitability for the job.  Reference Standards IS : 516-1959 – Methods of tests for strength of concrete. Equipment & Apparatus Compression testing machine (2000 KN) Curing tank/Accelerated curing tank Balance (0-10 Kg)   Procedure  Representative samples of concrete shall be taken and … Read more

AGGREGATE FLAKINESS INDEX VALUE (IS:2386-Part 1-1963)

Thickness Gauge

Objective For determination of flakiness index of coarse aggregate, where the  size of the coarse aggregate are larger than 6.3mm .  Reference Standards IS : 2386 (Part I) – 1963 – Method of test for aggregates for concrete (Part I) Particle size and shape. Equipment & Apparatus Thickness gauge Sieves [63, 50, 40, 31.5, 25, … Read more

SOUNDNESS OF CEMENT BY LE-CHATELIERS METHOD (IS:4031-Part 3-1988)

Le chatelier Apparatus

Overview In the soundness test a specimen of hardened cement paste is boiled for a fixed time so that any tendency to expand is speeded up and can be detected. Soundness means the ability to resist volume expansion. Apparatus Measuring Instruments NAME CAPACITY / RANGE / SIZE ACCURACY / LEAST COUNT Le-chatelier apparatus  Should be made … Read more