Description : If the depth of flow in a circular sewer is 1/4th of its diameter D, the wetted perimeter is A. /2 B. /4 C. /3 D. D
Last Answer : ANS: C
Description : A circular sewer section is preferred to because A. It is cheaper in construction B. It provides maximum area for a given perimeter C. It provides maximum hydraulic mean depth D. All the above
Last Answer : ANS: D
Description : In R.C. sewer pipes, the percentage longitudinal reinforcement to the cross-sectional area of concrete is kept A. 10.0 B. 5.0 C. 2.0 D. 0.25
Description : Sewer pipes are designed for maximum discharge with 25% to 33% vacant cross-sectional area for A. Unexpected large scale infiltration of stream water B. Unexpected increase in the population C. Under estimates of maximum and average flows D. All of the above
Description : If the depth of partial flow in a sewer of diameter 2 m, is 50 cm, its wetted perimeter is A. B. /2 C. /3 D. 2 /3
Description : In Chezy’s formula V = C rs for calculating the velocity of flow in circular sewer of diameter running full, the value of hydraulic mean radius is A. D B. D /2 C. D/3 D. D/4
Description : The hydraulic mean depth or the hydraulic radius is the ratio of (A) Area of flow and wetted perimeter (B) Wetted perimeter and diameter of pipe (C) Velocity of flow and area of flow (D) None of these
Last Answer : Answer: Option A
Description : The arrangement made for passing the sewer line below an obstruction below the hydraulic gradient lines called A. Inverted syphon B. Depressed sewer C. Sag pipe D. all of these
Description : A circular gravity aqueduct is not generally preferred to because of (A) Its maximum hydraulic mean depth (B) Maximum area per unit of wetted perimeter (C) Minimum cost of construction (D) Its proper support on the ground
Last Answer : (D) Its proper support on the ground
Description : Pick up the correct statement from the following: A. The circular section of sewers provides maximum hydraulic mean depth B. The circular sewers are provided for separate sewerage system C. The circular sewers work efficiently if the sections run at least half full D. All the above
Description : If is the diameter of upper circular portion, the area of cross-section of a standard egg shaped sewer, is A. D² B. D² C. D² D. D²
Last Answer : ANS: A
Description : Hydraulic radius is the ratio of (A) Wetted perimeter to flow area (B) Flow area to wetted perimeter (C) Flow area to square of wetted perimeter (D) Square root of flow area to wetted perimeter
Last Answer : (B) Flow area to wetted perimeter
Description : channel is said to be of most economical cross-section, if (A) It gives maximum discharge for a given cross-sectional area and bed slope (B) It has minimum wetted perimeter (C) It involves lesser excavation for the designed amount of discharge (D) All of the above
Last Answer : Answer: Option D
Description : weight of water, the hydraulic mean depth of the sewer and the bed slope w is the unit of the sewer, then the tractive force exerted by flowing water, is A. w r S S B. w r1/2 C. w r S D. w r2/3
Description : Antisyphonage pipe is fitted A. At the end of septic tanks B. On manholes C. With a W.C. trap D. At the beginning of sewer line
Description : You are asked to design sewer pipes of diameters 0.4 m to 0.9 m at maximum flow, you will assume the sewer flow running at A. Full depth B. Half full C. Two third full D. Three fourth full
Last Answer : ANS: B
Description : Aerobic activity is maximum A. In freshly produced sewage B. At sewer pipes C. In sewer treatment plants D. None of these
Description : Sewer pipes need be checked for A. Minimum flow B. Maximum flow C. Both A. and B. D. None of these
Description : Which one of the following tests is used for testing sewer pipes? A. Water test B. Ball test C. Mirror test D. All of these
Description : The porosity of sediments in sewer pipes, is usually taken as A. 0.010 B. 0.011 C. 0.012 D. 0.013
Description : Pick up the in-correct statement from the following: A. Manholes are provided in sewer pipes at suitable intervals B. Catch basins are generally provided in sewers for carrying drainage discharge C. Inlets are generally provided in all sewers D. None of these
Description : ¾th or ¼th extra space is left in sewer pipes at maximum discharge for A. Low estimates of the average and maximum flows B. Large scale infiltration of storm water C. Unexpected increase in population D. All the above
Description : The sewer pipes A. Carry sewage as gravity conduits B. Are designed for generating self-cleansing velocities at different discharge C. Should resist the wear and tear caused due to abrasion D. All the above
Description : Pick up the correct statement from the following: A. The water supply pipes carry pure water free from solid particles B. The water supply pipes get clogged if flow velocity is less than self ... carried up and down the hills and valleys D. The sewer pipes are generally laid along level hills
Description : Pick up the correct statement from the following: A. The sewer pipes of sizes less than 0.4 m diameter are designed as running full at maximum discharge B. The sewer pipes of sizes greater than 0.4 m ... discharge C. The minimum design velocity of sewer pipes is taken as 0.8 m/sec D. All the above
Description : The sewer pipe which carries sewage from a building for immediate disposal is A. House sewer B. Lateral sewer C. Intercepting sewer D. Main sewer
Description : A sewer pipe contains 1 mm sand particles of specific gravity 2.65 and 5 mm organic particles of specific gravity 1.2, the minimum velocity required for removing the sewerage, is A. 0.30 m/sec B. 0.35 m/sec C. 0.40 m/sec D. 0.45 m/sec
Description : A sewer running partially full and hurried with back filled, fails in compression due to A. Weight of the pipe B. Weight of the back fill C. Superimposed traffic loads D. All the above
Description : Pick up the correct statement from the following: A. The boning rod is used for checking the levels of the sewer inverts B. Manhole covers are made circular for the convenience of the cleaning staff C. A manhole is classified as shallow manhole if its depth is less than 0.9 m D. All the above
Description : If the side of a square sewer is 1000 mm, the diameter of a hydraulically equivalent circular section, is A. 1045 mm B. 1065 mm C. 1075 mm D. 1095 mm
Description : If D is the diameter of a circular sewer and D’ is the top horizontal diameter of an equivalent egg shaped section, the relationship which holds good, is A. D’ = 0.64 D B. D’ = 0.74 D C. D’ = 0.84 D D. D’ = 0.94 D
Description : running partially full with central angle , For a circular sewer of diameter A. d/D = ½ (1 – – B. a/A C. r/R = [1 – D. All the above
Description : If is the diameter of upper circular portion, the overall depth of New Egg shaped sewer section, is A. 1.250 D B. 1.350 D C. 1.425 D D. 1.625 D
Description : An inverted siphon is designed generally for A. One pipe B. Two pipes C. Three pipes D. Four pipes
Description : For sewers, inverted siphon is provided for A. One pipe B. Two pipes C. Three pipes D. Four pipes
Description : The reduced levels of the string at the consecutive sight rails A and B are 203.575 m, 203.475 m respectively. If the difference of their R.D.s is 10 m, the gradient of the sewer line is A. 1 in 100 upward B. 1 in 500 upward C. 1 in 100 downward D. 1 in 503 upward
Description : Drop manholes at the junctions of sewer lines, are provided if A. Invert level of a branch sewer is more than 60 cm that of the main sewer B. Sewer line runs along a main road C. Ordinary manhole cannot be built D. Two sewer lines intersect
Description : For laying a sewer line in a trench of 2 m width, an offset line is marked on the ground parallel to the given centre line at a distance of A. 100 cm B. 120 cm C. 140 cm D. 160 cm
Description : Ventilating shafts are provided to a sewer line at every A. 100 m B. 150 m C. 200 m D. 300 m
Description : Inter-distance between ventilation columns in a sewer line is kept A. 25 to 50 m B. 50 m to 100 m C. 100 m to 150 m D. 150 m to 300 m
Description : The most efficient cross section of sewers in a separate sewerage system is A. Parabolic B. Circular C. Rectangular D. New egged
Description : The suitable cross-section of sewers to carry combined flow, is A. Circular B. Egg shaped C. Rectangular D. Horse shoe shaped
Description : The most efficient cross-section of sewers in a combined sewerage system is A. Parabolic B. Circular C. Rectangular D. New egged
Description : Pickup the incorrect statement from the following: (A) The invert of pressure conduit is independent of the grade of the hydraulic gradient line (B) The pressure conduits may be taken uphill ... m (C) Aqueducts and tunnels sections are generally kept circular (D) None of these
Last Answer : (D) None of these
Description : Hydraulic diameter for non-circular ducts is equal to __________ times the area of flow divided by the perimeter. (A) Two (B) Three (C) Four (D) Eight
Last Answer : (C) Four
Description : The sewer which received discharge from two or more main sewers, is known as A. A trunk sewer B. An outfall sewer C. A main sewer D. An intercepting sewer
Description : Sewer manholes are generally provided at A. The change of gradient B. The change of direction C. The junctions of sewers D. All of these
Description : If the diameter of a sewer is 100 mm, the gradient required for generating self cleansing velocity is A. 1 in 60 B. 1 in 100 C. 1 in 120 D. None of these
Description : The sewer which transports the sewage to the point of treatment, is called A. House sewer B. Out-fall sewer C. Branch sewer D. Main sewer
Description : If a paper moistened with lead acetate for five minutes when placed in manhole turns black. The sewer certainly contains A. Hydrogen sulphide B. Carbon dioxide C. Methane D. Oxygen