Transportation Engg.-I

A transition curve has a radius which decreases from _________ at the tangent point to a designed radius.

A width of _________ is considered desirable for a road having single lane for vehicles of maximum width 2.44 m.

The rigid characteristics are associated with _________ action.

The ratio of contact pressure to tyre pressure is defined as _________ factor.

The property of the stones to withstand the adverse actions of weather may be called _________.

When the bitumen contains some inert materials it is sometimes called _________.

Keeping all these problems in view, bituminous stabilization seems to be a suitable solution for _________.

The distance travelled by the vehicle during the total reaction time known as _________ distance.

The spacing between contraction joints for 3.5 m slab width having thickness of 10 cm for plain cement concrete is _________.

A plate bearing test was carried out on sub grade using a 76 cm diameter rigid plate. A deflection of 1.25 mm was caused by a pressure of $0.84 \text{ kg/cm}^2$. The modulus of sub grade reaction is _________ $\text{kg/cm}^3$.

Why is widening of pavement necessary at horizontal curve? Explain the method of calculating widening and derive the formula.

Determine the absolute minimum radius and ruling minimum radius for minimum value of super elevation of horizontal curve for a design speed of $50 \text{ kmph}$.

What do you understand by sight distance? How does it affect the design and construction of highway?

Calculate the minimum non-passing sight distance on a highway at a descending gradient of 6%. Given the following data: Design speed = $80 \text{ kmph}$ Reaction time of driver = $2.5 \text{ secs}$ coefficient of friction between tyre and road surface = $0.4$.

What points will you bear in mind while deciding about the alignment of a new road?

What are the principles to be considered for an ideal highway alignment? Discuss in brief.

Name the usual tests employed for evaluating the road aggregates. What test values are generally considered suitable for road stones to behave as good construction materials?

What are the objects of carrying out penetration, ductility and softening point tests on bitumen?

What is understood by the following terms: (i) AADT (ii) 85 percentile speed (iii) Basic capacity (iv) PCU

The average normal flow of traffic on cross roads A and B during design period are 400 and 250 PCU per hour, the saturation flow values on these roads are estimated as 1250 and 1000 PCU per hour respectively. The all-red time required for pedestrian crossing is 12 secs. Design two phase traffic signal by Webster's method.

Discuss the functions of pavement layers, and draw the sketch of Flexible pavement layers in proper sequence.

Design a tie-bar system for a cement concrete pavement, given: Slab thickness = $20 \text{ mm}$, slab width = $3.35 \text{ m}$ Number of lanes to be tied = 2 Coefficient of friction between slab & subgrade = 1.5, weight of slab = $480 \text{ kg/m}^2$, Allowable working stress in steel = $1400 \text{ kg/cm}^2$ Maximum permissible bond stress for plain bars = $17.5 \text{ kg/cm}^2$ & deformed bars = $24 \text{ kg/cm}^2$.

Differentiate between WBM and WMM.

What do you understand by penetration macadam? What are the various materials used and what should be their requirements? Describe the methods of construction of a penetration macadam road.

Discuss the scope of soil stabilization in road construction.

Explain with sketches how the subsurface drainage system is provided to lower the W.T. and control seepage flow.