1a Using a waste factor of 11 percent determine the number o

1.a) Using a waste factor of 11 percent, determine the number of cubic yards of concrete needed to pour the continuous footings shown in Figures below. Assume that the wall is centered over the footing. The length of the continuous footing is 150 ft. Do not include wall volume. answer below(Show Work)

b) Using a waste factor of 10 percent, determine the number of pounds of rebar needed to reinforce the continuous footings shown in Figures below. Assume that the wall is centered over the footing. The length of the continuous footing is 150 ft. Do not include any amount for dowel bar.

Question 3 Using a waste factor of 11 percent, determine the number of cubic yards of concrete needed to pour the continuous footings shown in Figures below. Assume that the wall is centered over the footing. The length of the continuous footing is 150 ft. Do not include wall volume 1) 15.42 O 2) 12.42 3) 375.00 O 4) 212.00

Solution

(a) For calculating concrete quantity, we required dimensions of footing. From figure,

Width (b) = 2 \' 6\'\' = 2.5 foot

Depth of footing (d) = 1 foot

Length of footing (l) = 150 foot

Volume = l x b x d = 150 x 2.5 x 1 = 375 cubic feet

The wastage is 11 %, so above calculated volume should be increased by 11% ,

Final volume = 1.1 x 375 = 412.5 cubic foot

Answer should be reported in cubic yard,

1 cubic foot = 0.037037 cubic yard,

So final volume = 412.5 x 0.037037 = 15.42 cubic yard ( Option A)

(b) The steel present in footing as per drawing (excluding dowel bars as mentioned in question) is 4 bars of bar number 4, eah of length 150 feet.

Area of one bar = 0.2 square inch (Standard for bar no. 4)

Area of 4 such bar = 4 x 0.2 = 0.8 sq. inch

Area of 4 bars in square feet = (0.8) / (12²) = 0.00555 square foot

Volume of bars = Area x length

= 0.00555 x 150 = 0.818

Weight of reinforement bar = unit weight of steel in lb/ cubic foot x Volume in cubic foot

= 490 x 0.818

= 400.8 pound

Wastage is 10 %, So

Final weigth of reinforing steel = 1.1 x 400.8

= 440.88 pound ( Option D)