Surveying Multiple Choice Questions on “Compound Curve Elements”.
1. Length of tangent formula is same for all types of curves.
a) True
b) False
Answer: a
Clarification: Though there might be a change in the curve but length of the tangent value remains the same i.e., t = R tan (δ/2). Where R is the radius and δ is the deflection angle measured.
2. In a compound curve, both curves are of equal radius.
a) True
b) False
Answer: b
Clarification: A compound curve consists of two curves which will meet at P.C.C, known as Point of Compound Curve, in which it consists of one shorter radius curve another one of longer radius.
3. Compound curve can be designated by____________
a) Angle subtended by a chord of any curvature
b) Angle subtended by a chord of known radius
c) Angle subtended by a chord of known length
d) Angle subtended by a chord of any length
Answer: c
Clarification: For designing a Compound curve, we must know the required property like length from where it has to be started and where it has to end. It should also be known that the angle by which the chord subtends that is taken by the length determined.
4. The angle at point of intersection of tangents indicate____________
a) Radius of the arc
b) Angle of the arc
c) Curvature angle
d) Deflection angle
Answer: d
Clarification: The point where the two tangents will meet is described as the point of intersection, where the deflection angle between the two tangents can be known and later on used for further calculation like setting out curve.
5. Which of the following curves helps in avoiding overturning of vehicles?
a) Simple curve
b) Transition curve
c) Compound curve
d) Reverse curve
Answer: b
Clarification: Though compound curve serves as a best source in highways, it doesn’t provide the elevation needed to avoid overturning. Simple curve, reverse curve are not used in case of highways so those can be avoided. Transition curve provides the required amount of super elevation by using the formula provided and helps in decreasing overturning problem.
6. The tangent distance of a long curve is given as____________
a) (T = t_l – (t_s + t_l) frac{sin(Δ1)}{sinΔ})
b) (T = t_l + (t_s – t_l) frac{sin(Δ1)}{sinΔ})
c) (T = t_l + (t_s + t_l) frac{sin(Δ1)}{sinΔ})
d) (T = t_l + (t_s + t_l) frac{sin(Δ1)}{sinΔ})
Answer: c
Clarification: The tangent distance for a long curve can be given as (T = t_l + (t_s + t_l) frac{sin(Δ1)}{sinΔ}) in which tl = long tangent length, ts = short tangent length. These can be determined by their respective formulae and will be substituted in T for getting tangent distance.
7. What would be the short curve length of tangent if the radius of curvature is given as 43.21m and deflection of about76˚54ꞌ?
a) 34.13m
b) 43.13m
c) 43.31m
d) 34.31m
Answer: d
Clarification: The tangent length can be found out by using the formula,
t = R*tan (θ/2). On substitution, we get
t = 43.21*tan (76˚54ꞌ/2)
t = 34.31 m.
8. Find the value of the long curve tangent distance, if the tangent length of short and long curves were given as 23.21m and 65.87m. The total deflection is 67˚54ꞌ and the deflection angle at short curve is given as 28˚43ꞌ.
a) 112.06m
b) 121.06m
c) 211.06m
d) 121.68m
Answer: a
Clarification: The long curve tangent distance can be determined by,
T = tl + (ts+tl)* sin θ1/ sin θ. On substitution, we get
T = 65.87 + (23.21+65.87)* sin 28˚43ꞌ / sin 67˚54ꞌ
T = 112.06 m.
9. Determine the value of chainage of point of the compound curve, if the chainage at T1 is given as 226.43m and the curve length as 23.64m.
a) 205.07
b) 250.07
c) 207.7
d) 202.79
Answer: b
Clarification: Chainage at point of compound curve can be given as
Chainage at P.C.C = chainage of T1 + curve length. On substitution, we get
Chainage at P.C.C = 226.43 + 23.64
Chainage at P.C.C = 250.07 m.
10. If the radius of curvature is given as 76.98m and the deflection angle as 45˚21ꞌ, find the short curve length of a compound curve.
a) 60.93m
b) 6.93m
c) 9.63m
d) 3.69m
Answer: a
Clarification: The compound curve length can be determined by using the formula,
t = R*θ*π/180. On substitution, we get
t = 76.98*45˚21ꞌ*π/180
t = 60.93 m.
11. Find the value of long curve tangent length, if the radius is given as 76.43m and the deflection angle as 54˚32ꞌ.
a) 39.24m
b) 93.42m
c) 39.42m
d) 93.24m
Answer: c
Clarification: The formula for the determination of the long curve tangent length is given as,
t = R*tan (θ/2). On substitution, we get
t = 76.43*tan (54˚32ꞌ/2)
t = 39.42m.