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goldfish9776
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in ASTM C127 Aggregate test , why the weight of SSD is higher than water submerged weight?
tas why we will always feel that we will be lighter when we are in the water ?Baluncore said:Specific gravity, SG, of rock must have the SG of water (= 1) subtracted when rock is submerged to account for buoyancy.
If rock SG=3 and weighs 3 tonne, then when submerged in water it will weigh 2 tonne.
The weight of any water in the aggregate dissapears when it is submerged as it becomes part of the water.
Yes.goldfish9776 said:will always feel that we will be lighter when we are in the water ?
ASTM C127 is a standard test method for determining the density (unit weight) of aggregates. It involves determining the weight of a specific volume of aggregate in both a submerged and saturated-surface-dry (SSD) state.
Determining the submerged weight and SSD weight of aggregates is important because it helps to accurately measure the density of the aggregates. This information is crucial in construction and engineering projects, as it can affect the strength and stability of concrete and other building materials.
The test involves immersing a known volume of aggregate in water to determine its submerged weight, and then drying the same aggregate to a SSD state and weighing it again to determine its SSD weight. The difference between the two weights is used to calculate the density of the aggregate.
Submerged weight refers to the weight of an aggregate when it is fully immersed in water, while SSD weight refers to the weight of an aggregate when its pores are filled with water, but the surface is not submerged. The difference between these two weights is known as the absorption of the aggregate.
The results of the test can be affected by factors such as the type and size of the aggregate, the temperature and duration of submergence, and the accuracy of the measurement equipment. It is important to follow the standard test method closely and ensure proper calibration of equipment to obtain accurate results.