Problem

The grade of -5% is followed by a grade of +1%, the grades intersecting at the vertex (sta. 10 + 060). The change of grade is restricted to 0.4% in 20 m. Compute the length of the vertical parabolic sag curve in meters.

A. 250 m

B. 300 m

C. 350 m

D. 400 m

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Problem

The length of a summit vertical curve is 200 m. Tangent grades for the vertical curves are +3% and -2%. Compute the radius of the summit curve.

A. 3500 m

B. 4000 m

C. 6000 m

D. 5200 m

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Problem

A symmetrical parabolic curve 120m long passes through point X whose elevation is 27.79m and 54m away from PC. The back tangent of the curve has a grade of +2%. If PC is at elevation 27.12, what is the elevation of the summit?

A. 27.18

B. 28.81

C. 29.57

D. 27.83

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Problem

A -6% grade and a 2% grade intersect at STA 14+720 whose elevation is at 35.632 m. The two grades are to be connected by a parabolic curve, 160 m long. Find the elevation of the first quarter point on the curve.

A. 38.956 m

B. 38.778 m

C. 38.432 m

D. 38.156 m

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Situation

A highway intersection of 40° is to be connected by a 6-degree simple curve and 80-m long spiral on each end of the simple curve. Use arc basis.

1. What is the length of throw in meters?

A. 5.6

B. 1.8

C. 1.4

D. 2.6

2. What is the length of the short tangent in meters?

A. 26.86

B. 23.54

C. 28.72

D. 36.52

3. What is the total length of the curve in meters? Error, R = 240m.

A. 327.55

B. 167.55

C. 254.55

D. 312.55

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Problem

A spiral easement curve has a length of 2200m with a central curve having a radius of 320m. Determine the degree of the spiral at the third-quarter point.

A. 2.69

B. 3.58

C. 2.85

D. 3.21

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Problem

A spiral easement curve has a length of 85m and the radius of central curve is 200m. Determine the maximum velocity that a car could pass through this curve?

A. 72.56 kph

B. 80.54 kph

C. 77.87 kph

D. 83.65 kph

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Problem

The degree of curve of the central curve of a spiral easement curve is equal to 6°. If the maximum design velocity of the car passing thru the spiral curve is 80kph, determine the required length of the spiral.

A. 96.51

B. 92.54

C. 98.45

D. 101.23

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Problem

A 100 m-long spiral connects a tangent with a 4-degree circular curve. Find the spiral angle at SC.

A. 8° C. 10°

B. 9° D. 11°

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Problem

A spiral easement curve has a length of 100m with a central curve having a radius of 300m. Determine the offset distance from the tangent to the third-quarter point of the spiral.

A. 3.52 m

B. 2.34 m

C. 1.57 m

D. 2.96 m

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Problem

A spiral easement curve has a length of 100m with a central curve having a radius of 300m. Determine the degree of the spiral at the third-quarter point.

A. 3.12

B. 2.14

C. 3.82

D. 2.86

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