Test: Transportation Introduction - Civil Engineering (CE) MCQ

Increased productivity of various items such as agricultural and their distribution can lower the cost of products. The cost of transportation substantially reduces the prices.

The other 3 types of transport systems have to depend upon the roads to reach their destination point from the terminals that is railway station, harbours and airports.

The PMGSY aims to connect all the villages of population above 1000 by 2003 and population below 500 by 2007 it later became a part of bharat nirman programme.

Concept:

We know, Traffic capacity (q) = velocity (v) × density (k) ⇒ q = kV

For Case 1: When speed is constant, and density of the flow keeps on increasing at the same speed.

q = k × constant

∴ Flow becomes the linear function of density and with increase in density, flow increases linearly.

For Case 2: With decrease in the speed further, density increases linearly.

Here flow becomes the function the speed as well as density and hence flow becomes the parabolic function of density as density is varying with speed.

∴ After that V varies linearly with k, so q will vary parabolically with k.

As the base of the slab is frictionless less, the Slab base is free to expand in all directions.

⇒ ∴ Thermal stress = zero

The total roadway length in India is around5, 532,482km in march 2015 which is the 2nd largest network in the world.

Equilibrium cant =GV² / 127R

V - Design speed (kmph)

R - Radius of curvature (m)

For B.G track G = 1.676

The highway works all across the country are undertaken by NHAI, It was formed in 1988 and it has mandate to follow all the NHDP (national highway development programme) which is implemented in phases.

Correction for elevation: 7% increase per 300 m

So, correction =

= 249.66 m

Corrected length = 2000 + 249.66 = 2249.66 m

Correction for temperature:

Standard atmospheric temperature = 15 – 0.0065 × 535 = 11.5225°C

Rise of temp = 22.65°C – 11.523°C = 11.127°C

Correct length = 2249.66 + 250.320 = 2499.98 m

Check for total correction for elevation plus temperature

According to ICAO, this should not exceed by 35%.

For the option A:

For the speed - flow relationship:

It can be observed that the free flow speed (uf) is the speed when flow is negligible. 

At low speed, traffic volume would be low. With an increase in speed, volume increases up to a certain limit (approximately half of free-flow speed) then reduced similarly after that limit.

For option B: 

From the above diagrams, it can be observed that free flow speed (uf ) is the speed when density is negligible.

With the increase in density, traffic volume increases upto certain limit then decreases.

For option C: Traffic speed uf is affected by geometry and surface conditions of the road which is correct.

For option D: From the above statements we can conclude that uf is the speed at which flow is maximum and density is optimum is incorrect.