Highway and Railroad Engineering PDF

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PROBLEM NO. 1HIGHWAY AND RAILROAD ENGINEERINGREVIEWER FOR MIDTERM PROBLEM NO. Two converging tangents have azimuth of 300-degree and 90-degree respectively, while that of the common tangent is 320-degree. The distance from the point of intersection of the tangents to the P. of the second curve is 92...

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HIGHWA HIGHWAY Y AND RAILROAD ENGINEERING REVIEWER FOR MIDTERM PROBLEM NO. 1

PROBLEM NO. 2

Two converging tangents have azimuth of 300-degree and 90-degree respectively, while that of the common tangent is 320-degree. The distance from the point of intersection of the tangents to the P.I. of the second curve is 92m while the stationing of the P.I. of the first curve is 12 + 890.34. If the radius of the first curve is 280.72m. a. Determine the radius of the 2nd curve b. Determine the Sta. P.R.C. c. Determine the Sta. P.T

A vertical summit curve has a back tangent of +2.2% and a forward tangent of -2.9% intersecting at station 22 + 978.98 and elevation of 787.89m. The design speed of the curve is 80kph. Assuming coefficient of friction is 0.28 and a perception reaction time of 2.45sec. a. Solve for the safe stopping sight. b. Solve for the length of curve. c. Solve the elevation of the highest point of curve.

A car is approaching an easement curve having a rate of 0.5161 m/sec3 so as not to cause discomfort to the passengers. The length of spiral curve is 60 m. long, a. Solve the velocity of the approaching car in kph. b. Solve the required radius of the central curve of the easement curve to limit the centrifugal acceleration. c. Solve the length of the long tangent of the spiral curve if the distance along tangent from T.S. to S.C is 79.30 m. long.

A back tangent with -5% grade meets a 1% grade. Find the length of the parabolic curve if it is changing 0.40% in every 25m.

PROBLEM NO. 8 The design speed of a car passing through an easement curve is equal to 80 kph. The radius of the central curve of the spiral curve is equal to 260 m long. a. Solve the value of the rate of centrifugal acceleration in m/sec for this speed. b. Solve the length of the spiral curve based on the centrifugal acceleration. c. Compute for the length of throw.

PROBLEM NO. 9 The length of the sag curve having grades of –2.5% and +3.5% is equal to 310 m. a. Solve the length of the head lamp sight distance if the head lamps are 0.80 m. above the road surface and their beams tilt upward at an angle of 1.2 degrees above the longitudinal axis of the car. b. Solve the max. speed of the car passing through sag curve. c. Determine the perception reaction time in seconds if the coefficient of friction between the road pavement and tires is 0.25.

The central curve of an easement curve is on a 5° curve. Spiral easement curve has a length of throw equal to 1.02 m. at the T.S. a. Solve the required length of the spiral curve. b. Determine the velocity of the car passing through this curve so that it will not exceed the minimum centrifugal acceleration of 0.50 m/sec. c. What is the length of the long tangent of a spiral easement curve if the distance along the tangent up to S.C. is 73.60 m. long.

PROBLEM NO NO.. 11 The sight distance of a sag parabolic curve is 155.32 m. long with grade tangents of – 2% and +2.98% respectively. a. Solve the length of parabolic curve. b. Solve the max. Velocity of car that can maneuver on the curve to avoid possible collision of any approaching cars. c. Compute the perception-reaction time of the driver to avoid collision. Assume coefficient of friction between tires and pavement to be 0.38.

PROBLEM NO. 12 A parabolic sag curve has grade tangents of –3% and +2% intersecting at station (10+120.60) having an elevation of 326.42 m. A car approaches the curve at a speed of 80 kph. If the driver is driving on the nighttime, he has to switch on the headlight to avoid collision of cars moving towards his direction. The coefficient of friction between the tires and the pavement is 0.20. The perception-reaction time of the driver is ¾ of a seconds. a. Solve the head lamp sight distance considering the downward slope. b. If the length of the curve is 200 m. how high is the head lamp above the pavement if the beam light has an angle of tilt of 0.90° above the longitudinal axis of the car. c. Determine the maximum speed that a car could safely travel along this curve.

PROBLEM NO NO.. 13 The clearance to an obstruction is 9 m and the desirable sight distance when rounding a horizontal curve is 180 m. Determine the minimum radius of horizontal curve.

PROBLEM NO. 1 4 The length of a spiral curve is 80 m. with a radius of 280 m. at the central curve. a. Determine the offset distance from the tangent on the first quadrant point of the spiral. b. Solve the length of throw for the spiral curve. c. What is the maximum velocity that a car could pass through the easement curve?

As the transition curve are used to build up super elevation gradually, the radius of curvature should increase gradually from infinity to that of the circular curve, to enable convenient handling of the steering wheel to eliminate the shock due to the increase in centrifugal force and the radius of curvature should be inversely proportional to the length such that the rate of change of centrifugal acceleration should not cause discomfort to the driver. If a car approaches the easement curve at a speed of 90 kph and the permissible value of super elevation for the easement curve is 0.07. a. Solve the centrifugal acceleration of the car, so that it will not cause discomfort to the driver. b. Solve the radius of curvature of the easement curve for a length of transition curve of 120 m. to limit the centrifugal acceleration. c. Solve the lateral friction on the easement curve....