Write three paragraphs discussing the possible sources of er

Write three paragraphs discussing the possible sources of error of Standard Test Method for specific gravity and absorption of coarse aggregate assuming that there was no error in calculations but in the procedure itself.

Solution

Possible Sources of Errors in Absorption Test are:

1. If the aggregates are not oven dried before immersion:

This is very important that the aggregates must be completely oven dried at 110 Celcius before immersion, otherwise the values of the specific gravity or absorption will be highly altered. If this happens, then there would already be moisture present in the pores, and therefore the calculated values of the moisture absorbed will be less, and therefore the results get varied.

2. While making the aggregates SSD (Saturated Surface Dry) make sure to use a cloth towel. If you use a paper towel, the water from the pores may get extracted, and therefore that will create the error. This lowers the moisture content from the SSD condition to lower, and therefore the absorption capacity value will get altered(lowered.)

3. Please note that bulk specific gravity is the lowest of the specific gravities, bulk SSD specific gravity is in the middle and apparent specific gravity is the highest. So if this does not reflect in the results, then there would be an error. Make sure to keep the aggregates completely immersed in water for 16 to 17 hours.