Bissoy.com
Doctors Medicines MCQs Q&A

Calculate the value of minimum base width for an elementary triangular concrete gravity dam supporting 72 m height of reservoir water and full uplift? (Take specific gravity of concrete as 2.4 and coefficient of friction as 0.7)

Calculate the value of minimum base width for an elementary triangular concrete gravity dam supporting 72 m height of reservoir water and full uplift? (Take specific gravity of concrete as 2.4 and coefficient of friction as 0.7) Correct Answer 73.5 m

Using formula – Case 1: B = H / (Sc – c)1/2 (For full uplift c = 1 and specific gravity of concrete = 2.4 ) = 72/ (2.4 – 1)1/2 = 60.85 m Case 2: B = H/μ (S – 1) where μ = coefficient of friction taken as 0.7 B = 72 / 0.7 x 1.4 = 73.46 m The highest among the two base width value is to be selected i.e. B = 73.46 m.

Related Questions

Consider the following statements related to uplift pressure in gravity dams: 1. A drainage gallery reduces the uplift pressure at all levels below the gallery. 2. A drainage gallery below upstream water level reduces the uplift pressure at all levels below the upstream water level. 3. A grout curtain near the heel reduces seepage and uplift pressure everywhere on the gravity dam whatever the upstream water level. Which of the above statements are correct?
The ratio of base width 'b' to height 'h' of an elementary profile of a gravity dam, from 'no tension' consideration, is given by Where G = specific gravity of dam material K = uplift pressure intensity and  μ = coefficient of friction           
The ratio of base width ‘b’ to height ‘h’ of an elementary profile of a gravity dam from ‘no tension’ consideration is given by Where G = specific gravity of dam material K = uplift pressure intensity μ = coefficient of friction
A concrete gravity dam having a maximum reservoir level at 200 m and the RL of the bottom of the dam 100 m. The maximum allowable compressive stress in concrete is 3000 KN/m2 and the specific gravity of concrete is 2.4. Calculate the height of the dam and check whether it is a high dam or low dam.
Consider the following statements in respect of dams: 1. In a gravity dam, a grout curtain is provided near the toe to reduce the exit gradient. 2. A drainage gallery with its drainage pipe system provided in a gravity dam reduces the uplift pressure at all levels below the upstream water level. 3. An earthquake acceleration of 0.1 g acting vertically downward causes a decrease of 10% in the limit weight of concrete and of water in a gravity dam. 4. The Tehri dam is a gravity dam. Which of the above statements are correct?
The base width of a solid gravity dam is 35 m and the specific gravity of dam material is 2.45. What is the approximate allowable height of the dam having an elementary profile without considering the uplift?
The water level in a municipal reservoir has been decreasing steadily during a dry spell, and there is a concern that the drought could continue for another 60 days. The local water company estimates that the consumption rate in the city is approximately 107 L/day. The state conservation service estimates that rainfall and stream drainage into the reservoir coupled with evaporation from the reservoir should yield a net water input rate of 106 exp (-t/100) L/day, where t is the time in days from the beginning of the drought, at which time the reservoir contained an estimated 109 liters of water. Integrate the balance to calculate the reservoir volume at the end of the 60 days of continued drought.
Which of the following is/are not true for a triangular pyramid? (a) Triangular pyramid has six faces. (b) Triangular pyramid has four vertices. (c) Triangular pyramid has six edges. (d) The sum of the number of faces, vertices and edges of a triangular pyramid is 14. (e) Triangular pyramid is also known as a tetrahedron.
During rainy season, huge inflow of water takes place into a reservoir. Measures are taken to clear the reservoir while water keeps flowing into it at a constant rate. It has been observed that seven and five men can clear the reservoir in 20 and 50 days, respectively, with the initial quantity of water in the reservoir being 24 and 36 kilolitres, respectively. What is the rate of inflow of water into the reservoir in litres per day?
A low gravity dam of elementary profile made up of concrete of relative density 2.57 and safe allowable stress of foundation material 4.2 MPa. What is the maximum height of the dam without considering the uplift force?