Answer to Question #311902 in Civil and Environmental Engineering for Oxian

Question

The design of a concrete mix requires 1173 kg/m3

of gravel in dry condition, 582 kg/m³ of sand in dry condition, and 157 kg/m³of free water. The gravel available at the job site has a moisture content of 0.8% and absorption of 1.5%, and the available sand has a moisture content of 1.1% and absorption of 1.3%. What are the masses of gravel, sand, and water per cubic meter that should be used at the job site?

Answer 1

Answer:

- the weight of the gravel is 1183.56 kg/m³

- the weight of sand is 588.98 kg/m³

- the weight of water is 165.784 kg/m³

Explanation:

 Given the data in the question;

mixture content of the gravel = 1173 kg/m³

sand content = 582 kg/m³

free water content = 157 kg/m³

moist of gravel = 0.9%

absorption of gravel = 1.5%

moist of sand = 1.2%

absorption of sand = 1.5% 

masses of gravel, sand, and water per cubic meter that should be used at the job site ?

To get the weight of moist gravel, we use the following equation;

Weight of moist gravel = content of gravel × ( 1 + moist of gravel )

we substitute

Weight of moist gravel = 1173 × ( 1 + 0.9%)

Weight of moist gravel = 1173 × ( 1 + 0.009)

Weight of moist gravel = 1173 × 1.009

Weight of moist gravel = 1183.56 kg/m³

Therefore, the weight of the gravel is 1183.56 kg/m³

To get weight of the sand, we use the following formula;

Weight of sand = sand content × ( 1 + moist of sand )

we substitute

Weight of sand = 582 × ( 1 + 1.2% )

Weight of sand = 582 × ( 1 + 0.012 )

Weight of sand = 582 × 1.012

Weight of sand = 588.98 kg/m³

Therefore, the weight of sand is 588.98 kg/m³

Weight of mix water= $mix-Water weight$

= 157-1173(0.9%-1.5%) - 582(1.2% - 1.5%)

= 157+7.038+1.746

= 165.784kg/m³

Therefore, the weight of water is 165.784kg/m³