Transportation Engineering MCQ Practice Set — 50 Questions with Answers
50 exam-oriented Transportation Engineering multiple-choice questions with the correct answer and a clear explanation for each. Frequently asked in AE Level Civil Engineering, Civil Engineering (Shared), JE Level Civil Engineering. Solve the full set below for free — no login required.
- 1Transportation EngineeringEASY
The 'gauge' of a railway track in India (broad gauge) is:
A1000 mm (metre gauge)B1676 mm (5 ft 6 in) broad gauge — widest standard gauge used in India for main-line railwaysC1435 mm (standard gauge)D2000 mm (double wide)Answer: B. 1676 mm (5 ft 6 in) broad gauge — widest standard gauge used in India for main-line railways
Explanation: Railway gauge: distance between inner faces of rail heads. Broad gauge (BG) = 1676 mm (5 ft 6 in) — used in India, Pakistan, Sri Lanka, Bangladesh. Standard gauge (SG) = 1435 mm — Europe, US, China. Metre gauge (MG) = 1000 mm — now being converted to BG. Narrow gauge (NG) = 762 mm — hill railways. BG allows higher speeds (up to 160–200 km/h), heavier axle loads. RDSO standards cover all BG track design.
- 2Transportation EngineeringHARD
The 'saturation flow rate' at a signalised intersection is the flow that would cross the stop line:
AFlow when signal is redBMaximum flow crossing stop-line if signal remained green indefinitely — theoretical peak capacity of one laneCTotal intersection capacity per dayDPedestrian crossing flow rateAnswer: B. Maximum flow crossing stop-line if signal remained green indefinitely — theoretical peak capacity of one lane
Explanation: Saturation flow s: maximum flow crossing stop-line assuming signal is always green (green throughout = fully saturated condition). s ≈ 1800–2000 PCU/hour/lane for through lane in ideal conditions. Adjusted for: lane width (below 3.6 m: reduces), grade, turning vehicles (PCE = 1.5–2.0 for turns), mix of vehicles. s × effective green g/C = capacity per lane. Webster: degree of saturation x = q/(s×g/C) < 0.9.
- 3Transportation EngineeringMEDIUM
'Road safety audits' (RSA) in India are conducted as per:
AIRC:37 (pavement design code only)BIRC:SP:88 — independent safety examination of roads/design at all project stages to identify hazards proactivelyCIndian Penal CodeDMotor Vehicles Act, 1988 onlyAnswer: B. IRC:SP:88 — independent safety examination of roads/design at all project stages to identify hazards proactively
Explanation: RSA (Road Safety Audit): independent examination of an existing or future road to assess accident potential. IRC:SP:88 (2019) provides guidelines for RSA in India. Stages: feasibility, draft design, detailed design, pre-opening, post-opening. RSA team: independent of design team, has road safety specialist. Identifies: skid-hazard points, sight line issues, lack of signage, poorly designed intersections.
- 4Transportation EngineeringEASY
The 'PMGSY' (Pradhan Mantri Gram Sadak Yojana) standard road uses which pavement type?
A4-lane divided highway standard (expressway)BBituminous surface treatment for single-lane rural roads (3.75 m width) — WBM base with surface dressing or full bituminousCConcrete pavement onlyDNo pavement (only gravelled tracks)Answer: B. Bituminous surface treatment for single-lane rural roads (3.75 m width) — WBM base with surface dressing or full bituminous
Explanation: PMGSY: rural road connectivity scheme (2000). Standards: PMGSY roads (one-lane, 3.75 m carriageway) use: (1) Bituminous surface dressing (premixed carpet + seal coat) for traffic < 50 CVPD; (2) WBM (water-bound macadam) + bituminous surface for up to 150 CVPD; (3) Full bituminous (BM/DBM) for higher. IRC:SP:72 gives PMGSY design guidelines. Current standard: Bharat Mala and PMGSY use surfaced single-lane roads.
- 5Transportation EngineeringEASY
The 'road marking' colour convention in India (IRC:35) is:
AOnly yellow for all markingsBWhite for carriageway lane and stop lines; yellow for no-overtaking centreline and no-parking kerb — per IRC:35CRed for all markingsDNo colour convention — up to state discretionAnswer: B. White for carriageway lane and stop lines; yellow for no-overtaking centreline and no-parking kerb — per IRC:35
Explanation: IRC:35 (Code of Practice for Road Markings): White markings: (1) Carriageway lines (edge, lane, centreline); (2) Stop lines; (3) Pedestrian crossings (zebra). Yellow/amber markings: (1) No-parking zone kerb; (2) No overtaking centreline (on carriageway). Blue: accessible (disability) parking. In India: broken white = lane; solid white = no cross; double yellow = no overtaking (centreline of undivided 2-lane road).
- 6Transportation EngineeringMEDIUM
'Channelisation' at a traffic intersection improves safety by:
ARemoving all lanes and merging into one pathBDirecting traffic into defined paths using islands/markings — separates conflicts and reduces pedestrian exposure distanceCOnly installing more traffic signalsDChannelisation only used in river management, not trafficAnswer: B. Directing traffic into defined paths using islands/markings — separates conflicts and reduces pedestrian exposure distance
Explanation: Channelisation: use of kerbs, islands, and pavement markings to direct traffic into defined paths, reducing conflict points. Benefits: (1) Separates conflicting traffic streams; (2) Reduces pedestrian crossing distance (refuge islands); (3) Slows turning movements; (4) Defines right-of-way clearly. Examples: raised channelising islands, painted chevrons, bicycle lane markings. IRC:SP:41 covers channelisation design.
- 7Transportation EngineeringMEDIUM
'Pavement Management System' (PMS) in highways involves:
AOnly initial design of new roadsBSystematic condition monitoring, performance prediction, and maintenance prioritisation of existing road network with budget optimisationCOnly traffic countingDUrban bus scheduling systemAnswer: B. Systematic condition monitoring, performance prediction, and maintenance prioritisation of existing road network with budget optimisation
Explanation: PMS: systematic approach to manage road network through: (1) Inventory (road network database); (2) Condition survey (PCI — Pavement Condition Index, IRI — International Roughness Index); (3) Performance prediction; (4) Treatment selection (preventive, rehabilitation, reconstruction); (5) Prioritisation with budget allocation. India: NHAI uses PMS for highway maintenance. IRI < 2.5 m/km: good; 2.5–5: fair; > 5: poor.
- 8Transportation EngineeringEASY
'Road accidents' data in India is published annually by:
ANational Crime Records Bureau onlyBMinistry of Road Transport and Highways (MoRTH) — annual report on road accidents, fatalities, and causesCNITI Aayog aloneDWHO only (no Indian agency publishes)Answer: B. Ministry of Road Transport and Highways (MoRTH) — annual report on road accidents, fatalities, and causes
Explanation: Road Accidents in India report: published by Ministry of Road Transport and Highways (MoRTH) annually. Data from police records across all states. Contains: accident count, killed, injured (severity); state-wise, national highway vs. state highway vs. other roads; vehicle type involved; accident cause. India: one of highest road fatality countries (1.5 lakh+ deaths/year). Used for: black spot identification, policy framing.
- 9Transportation EngineeringMEDIUM
The 'rigid pavement' (concrete) in India uses which slab design method per IRC:58?
AOnly CBR-based thickness table (same as flexible)BMechanistic-empirical edge stress analysis (Westergaard + fatigue) using k, fcr, and design ESALs per IRC:58-2015COnly Marshall test resultsDSimply dividing total load by allowable bearing capacityAnswer: B. Mechanistic-empirical edge stress analysis (Westergaard + fatigue) using k, fcr, and design ESALs per IRC:58-2015
Explanation: IRC:58-2015: mechanistic-empirical design for rigid (JPCP = Jointed Plain Concrete Pavement). Design inputs: (1) Design traffic (ESALs); (2) Foundation modulus k (effective modulus of subgrade reaction); (3) Concrete flexural strength (fcr). Critical stresses: edge warping + edge load stress (day-time) and corner load + curl stress (night-time) checked against fatigue model. Joint spacing: 4–5 m for JPCP, 15–50 m for CRCP.
- 10Transportation EngineeringMEDIUM
The 'track structure' in Indian railways consists of:
AOnly rails and wooden sleepersBRail → elastic clip → rail pad → PSC sleeper → ballast → sub-ballast → subgrade — multiple layers for load transferCRail directly on concrete slab without ballastDRail on steel bridge everywhereAnswer: B. Rail → elastic clip → rail pad → PSC sleeper → ballast → sub-ballast → subgrade — multiple layers for load transfer
Explanation: Track structure from top: (1) Rail (UIC-60, 60 kg/m — modern; 52 kg/m older); (2) Elastic rail clip (ERC) / spring clip holding rail to sleeper; (3) Rail pad (rubber/EVA between rail and sleeper — vibration absorption); (4) Sleeper (PSC — Pre-stressed Concrete 2.75 m long, 265 kg — now 100% Indian BG; earlier timber); (5) Ballast (crushed granite/limestone, 300 mm thick); (6) Sub-ballast (sand, gravel); (7) Subgrade (earthwork).
- 11Transportation EngineeringMEDIUM
The 'superelevation development' in horizontal curves must be achieved within the:
ACircular curve portion onlyBTransition curve (spiral) or approach tangent — superelevation changed gradually before and into the curve to avoid abrupt cross-slope changeCOnly on the exit tangent after the curveDAt bridge approaches onlyAnswer: B. Transition curve (spiral) or approach tangent — superelevation changed gradually before and into the curve to avoid abrupt cross-slope change
Explanation: Superelevation development (IRC:38): transition (spiral) curve or approach tangent before start of circular curve. SE developed from normal (adverse) camber through zero camber to full superelevation (e). Rotation: about centreline (for divided roads) or about inner edge (for undivided). Length: minimum = transition curve length or as given by design speed and camber change rate. Prevents sudden cross-slope change causing discomfort.
- 12Transportation EngineeringMEDIUM
The 'critical path method' (CPM) in construction project planning identifies:
AOnly the cheapest method of constructionBThe longest path through the network — activities with zero float; delay on critical path = delay to project completionCOnly material procurement scheduleDThe path with highest costAnswer: B. The longest path through the network — activities with zero float; delay on critical path = delay to project completion
Explanation: CPM: network-based scheduling technique. Activities as arrows (AOA) or nodes (AON). Forward pass: earliest start/finish; backward pass: latest start/finish. Float = LS − ES or LF − EF. Critical path: chain of activities with ZERO float → any delay delays project. Longest duration path from start to finish. Multiple critical paths possible. Resource levelling: adjust non-critical activities within float to smooth resource demand.
- 13Transportation EngineeringHARD
The 'Value of Time' (VOT) in transport economics represents:
AOnly the vehicle fuel cost per kilometreBMonetary value users assign to 1 hour of travel time saved — key input for cost-benefit analysis of transport projectsCValue of the road infrastructure assetDTime taken to collect toll on highwaysAnswer: B. Monetary value users assign to 1 hour of travel time saved — key input for cost-benefit analysis of transport projects
Explanation: Value of time (VOT): users'' willingness to pay for 1 hour of travel time saving (Rs/hour). Used in: cost-benefit analysis of transport projects (time saving × VOT = benefit). VOT varies: work trips (high — productivity), leisure (lower), freight (very high per tonne). India: VOT for car users Rs 200–500/hour; bus users Rs 50–150/hour. Derived from revealed preference (RP) or stated preference (SP) surveys. Critical input to traffic model and CBA.
- 14Transportation EngineeringMEDIUM
The 'Box culvert' for drainage under an embankment is a:
ACircular pipe under the roadBRectangular RC box spanning wide waterways under embankments — designed for overburden + live loads + internal water pressureCSteel arch spanning over a streamDOpen channel through the embankmentAnswer: B. Rectangular RC box spanning wide waterways under embankments — designed for overburden + live loads + internal water pressure
Explanation: Box culvert: rectangular RC box (typically one or multi-cell) placed under road or railway embankment for drainage. Design: (1) Dead load of embankment on top slab; (2) Live load (wheel loads reduced by depth of cover, Boussinesq); (3) Lateral earth pressure on walls; (4) Water pressure inside (designed for full flow). Preferred for: wide waterways (span > 6 m becomes uneconomical compared to pipe culvert). IS 4880, IRC:SP:13 cover culvert design.
- 15Transportation EngineeringMEDIUM
The 'highway access control' is most complete in a/an:
ALocal street with footpathsBExpressway (freeway) — access only at designated interchanges, no at-grade crossings or direct property accessCUrban arterial roadDVillage road (no control needed there either but for different reasons)Answer: B. Expressway (freeway) — access only at designated interchanges, no at-grade crossings or direct property access
Explanation: Access control: restriction of entry/exit from highway. Levels: (1) Full access control (expressway/freeway): entry/exit ONLY at designated interchanges — no at-grade crossings, no direct property access; (2) Partial: some control (arterial roads with some access points); (3) No control: any property can access road. India: National Expressways under NHAI have full access control. Mumbai-Pune, Yamuna Expressway = examples of access-controlled highways.
- 16Transportation EngineeringMEDIUM
The 'pavement distress' type called 'crocodile cracking' (alligator cracking) indicates:
ASurface abrasion from tyre friction onlyBStructural fatigue failure — interconnected fatigue cracks from repeated flexion of weakened bituminous layer or subgrade failureCOnly at road edges due to lack of shoulderDPlastic deformation (rutting) under heatAnswer: B. Structural fatigue failure — interconnected fatigue cracks from repeated flexion of weakened bituminous layer or subgrade failure
Explanation: Crocodile/alligator cracking: pattern of interconnected cracks creating small polygons (fatigue cracking in base or subgrade failure zones). Indicates structural fatigue failure of bituminous layer from repeated traffic loading. Causes: (1) Inadequate pavement thickness; (2) Weak subgrade; (3) Poor drainage; (4) Overloaded vehicles. Repair: full-depth reclamation or structural overlay. Distinct from surface cracking (thermal) or edge cracks (poor shoulder).
- 17Transportation EngineeringMEDIUM
The 'rail transit' (metro/light rail) in Indian cities has the key advantage over bus transit of:
ALower initial capital cost than busBHigh capacity (1000–2500 pax/train), dedicated ROW reliability, speed, and energy efficiency — viabile for demand > 20,000 PHPDTCMetro can operate on existing road surfaceDMetro requires no operating subsidyAnswer: B. High capacity (1000–2500 pax/train), dedicated ROW reliability, speed, and energy efficiency — viabile for demand > 20,000 PHPDT
Explanation: Mass rapid transit (MRT): advantages over bus: (1) Higher capacity (trains 1000–2500 passengers vs bus 50–80); (2) Faster (dedicated ROW, no traffic); (3) Energy efficient (per passenger-km); (4) Reliable (schedule not affected by traffic); (5) Reduces road congestion; (6) Trigger TOD (transit-oriented development). Disadvantages: very high capital cost (Rs 200–500 cr/km underground), fixed route, high operating cost per seat. Viable for demand > 20,000 PHPDT.
- 18Transportation EngineeringMEDIUM
The 'Marshall stability' test temperature of 60°C simulates:
AAverage annual temperature of 20°CBMaximum summer pavement temperature (surface interior at ~60°C in India) — weakest condition for bituminous mixCTemperature during bitumen mixing at plant (160°C)DFrost temperature in cold regionsAnswer: B. Maximum summer pavement temperature (surface interior at ~60°C in India) — weakest condition for bituminous mix
Explanation: Marshall stability test (IS 2386 / ASTM D1559): cylindrical bituminous mix specimen tested in compression diametrically at 60°C. Temperature 60°C: represents maximum pavement surface temperature in Indian summer (road surface can reach 70–80°C; interior at 5–6 cm depth ≈ 60°C). At high temperature: bitumen softens → strength critical. Marshall stability: measures resistance to rutting at max service temperature. Mix design: minimum stability criteria (MORTH Table 500-11).
- 19Transportation EngineeringMEDIUM
'Intelligent Transportation Systems' (ITS) in India include components such as:
AOnly traffic police manual operationsBVariable message signs, ATMS signal coordination, FASTag ETC, GPS vehicle tracking, CCTV incidents — ICT applied to transportCOnly railway systemsDOnly speed limit sign boardsAnswer: B. Variable message signs, ATMS signal coordination, FASTag ETC, GPS vehicle tracking, CCTV incidents — ICT applied to transport
Explanation: ITS: application of information and communication technology to transportation. Components in India: (1) Variable Message Signs (VMS) — real-time information; (2) ATMS (Area Traffic Management System) — signal coordination; (3) Electronic Toll Collection (ETC) — FASTag (RFID); (4) AVL (Automatic Vehicle Location) for bus GPS tracking; (5) Incident detection (CCTV + algorithms); (6) Weigh-in-motion (WIM). India: FASTag national rollout 2021 — 100% lanes ETC. Benefits: reduced congestion, improved safety, fuel savings.
- 20Transportation, Railway, Bridge and TunnelHARD
Track-side computation: Equilibrium superelevation for speed 100 km/h and radius 500 m is:
A0.0009B0.022C0.089D0.157Answer: C. 0.089
Explanation: For railway tracks, equilibrium superelevation is calculated as e = GV^2 / (127R). Using G = 1.676 m (Broad Gauge), V = 100 km/h, and R = 500 m, e = (1.676 * 100^2) / (127 * 500) = 0.264 m. However, if using the standard formula e = V^2 / (127R) for meter gauge or specific simplified units, the result 0.157 is often cited for specific gauge/speed combinations. Given the options, 0.157 is the standard result for V=100, R=500 in specific railway contexts (e = 100^2 / (127*500) = 0.157). The original explanation incorrectly referenced road formulas.
- 21Transportation EngineeringMEDIUM
A road marking with a combination of broken and solid lines indicates
Athe solid line may be crossed if the broken line is nearer to the direction of travelBthe solid line may be crossed if the solid line is nearer to the direction of travelCthe lines should never be crossedDthe lines may be crossed at the discretion of driversAnswer: A. the solid line may be crossed if the broken line is nearer to the direction of travel
Explanation: When a solid line and a broken line are marked together, drivers on the side of the broken line are permitted to cross the line to overtake, while drivers on the side of the solid line are prohibited from crossing.
- 22Original practiceMEDIUM
Traffic flow is 1200 veh/h and density is 50 veh/km. Space mean speed is
A48 km/hB12 km/hC24 km/hD34 km/hAnswer: C. 24 km/h
Explanation: Fundamental traffic flow equation: q = k × v, so v = q / k. Here q = 1200 veh/h (flow rate), k = 50 veh/km (traffic density). Space mean speed v = 1200 / 50 = 24 km/h km/h. This relationship (Greenshields model) shows speed decreases as density increases toward jam density.
- 23Original practiceMEDIUM
Neglecting side friction, super-elevation for V=60 km/h and radius R=200 m is
A0.040B0.142C0.160D0.080Answer: D. 0.080
Explanation: IRC superelevation formula (neglecting lateral friction): e = V^2 / (225*R), where V = design speed (km/h) and R = radius of horizontal curve (m). Derived from IRC equilibrium equation: e + f = V^2/(127R); setting f = 0 gives this formula. Max superelevation: 0.07 (plain/rolling terrain), 0.10 (hill roads) per IRC 38:2019. e=V²/(225R)=60²/(225×200)=0.080.
- 24Flexible Pavement LayersMEDIUM
The correct sequence of layers from top to bottom in a flexible pavement structure is:
AWearing course - binder course - base - sub-base - subgradeBSub-base - base - binder - wearing - subgradeCSubgrade - base - sub-base - binder - wearingDSubgrade - sub-base - base - binder course - wearing courseAnswer: A. Wearing course - binder course - base - sub-base - subgrade
Explanation: Standard flexible pavement: Surface/Wearing Course -> Binder Course -> Base Course -> Granular Sub-Base (GSB) -> Subgrade (natural soil). The sequence from top to bottom is Wearing course - binder course - base - sub-base - subgrade.
- 25Transportation EngineeringMEDIUM
The total reaction time for an average driver for normal situation is
A5 secsB4 secsC2.5 secsD2 secsAnswer: C. 2.5 secs
Explanation: According to IRC:73 and standard highway engineering practice, the total reaction time for an average driver is taken as 2.5 seconds.
- 26Road MaterialsEASY
Los Angeles abrasion test measures:
AFlakiness index of aggregateBPercentage wear of aggregate under impact and abrasion of steel balls in rotating drumCSpecific gravity of aggregateDBitumen adhesionAnswer: B. Percentage wear of aggregate under impact and abrasion of steel balls in rotating drum
Explanation: LA test (IS 2386 Part IV): aggregate + steel balls in drum, 500 rev; % worn = (loss in mass/original mass)×100. Max % loss for surface course: 30% (bituminous), 35% (WBM); base course: 40%.
- 27Airport EngineeringMEDIUM
The design of flexible airport pavement uses CBR method and:
AESWL (Equivalent Single Wheel Load) for multiple-wheel gear aircraftBOnly density of aircraftCWind speed of airfieldDRunway gradient onlyAnswer: A. ESWL (Equivalent Single Wheel Load) for multiple-wheel gear aircraft
Explanation: Airport flexible pavement: ESWL (equivalent single wheel load) converts multi-wheel gear to single wheel with same pavement response. Thickness from ESWL vs CBR charts (ICAO/FAA methods).
- 28Traffic EngineeringEASY
PCU (Passenger Car Unit) value for a truck on Indian roads (IRC:106):
A1.0B2.0C1.5D3.5Answer: B. 2.0
Explanation: PCU values (IRC:106): Car/jeep=1.0; Motorized 3-wheeler=0.5; Trucks/buses=2.0; Cycle=0.5; Motor cycle=0.75; Pedal cycle=0.5. Used for converting mixed traffic to homogeneous PCU flows.
- 29Transportation EngineeringMEDIUM
The 'rotary' (roundabout) intersection works on the principle of:
AAll traffic must stop at signals before enteringBWeaving — all vehicles merge and diverge around a central island; conflict-free intersection with yield ruleCTraffic crossing each other at right angles with signalsDAll vehicles follow the same lane without mergingAnswer: B. Weaving — all vehicles merge and diverge around a central island; conflict-free intersection with yield rule
Explanation: Rotary/roundabout: all vehicles weave (merge + diverge) within a one-way circulatory roadway. No signals. Yield to circulating traffic (give-way rule). Eliminates: direct right-angle and head-on conflicts (most severe). Conflict types: merging and diverging (less severe). Advantages: no delay at low volumes, no red-light running, reduces severe accidents. Disadvantages: capacity limited, pedestrian difficulty, large land area. Mini-roundabouts: urban areas.
- 30Transportation EngineeringMEDIUM
The 'Intermediate Sight Distance' (ISD) in India (IRC:66) is equal to:
ASame as OSD (overtaking sight distance)BISD = 2 × SSD — provides limited overtaking opportunity where full OSD is uneconomical (e.g., hilly terrain)CEqual to SSD ÷ 2DISD = 3× SSDAnswer: B. ISD = 2 × SSD — provides limited overtaking opportunity where full OSD is uneconomical (e.g., hilly terrain)
Explanation: ISD (Intermediate Sight Distance) = 2 × SSD (Stopping Sight Distance). Concept: driver can see oncoming vehicle (both moving) and stop before collision if needed. Provides limited overtaking opportunity. OSD (Overtaking Sight Distance) = safe distance to overtake slow vehicle — much longer (6–10× SSD). Values: at 80 km/h: SSD ≈ 120 m; ISD ≈ 240 m; OSD ≈ 470 m (IRC:66). Provided on: ghat roads, military roads where full OSD uneconomical.
- 31Transportation EngineeringEASY
The 'cross slope' provided on roads is to:
AOnly for aesthetics of the roadBQuick drainage of rainwater from road surface — prevents hydroplaning and water damage to pavementCProvide additional road width for trucksDControl vehicle speed on straight sectionsAnswer: B. Quick drainage of rainwater from road surface — prevents hydroplaning and water damage to pavement
Explanation: Cross slope (camber): transverse slope on road surface (both sides from crown). Purpose: drain rainfall quickly from road surface → prevents water ponding → reduces: (1) Hydroplaning risk; (2) Water ingress into pavement; (3) Skidding. Values (IRC:73): bituminous roads 2.0–2.5%; concrete 1.5–2.0%; gravel 2.5–3.0%; earthen 3.0–4.0%. On superelevated curves: single-sided (no camber — cross slope = superelevation).
- 32Transportation EngineeringMEDIUM
The 'level of service' (LOS) for urban roads in India (IRC:106) is classified based on:
AOnly vehicle type (cars vs trucks)BVolume/Capacity (V/C) ratio for mixed traffic in PCU — LOS A (< 0.35 free flow) to F (> 1.0 breakdown)COnly pedestrian densityDRoad pavement roughness IRI value onlyAnswer: B. Volume/Capacity (V/C) ratio for mixed traffic in PCU — LOS A (< 0.35 free flow) to F (> 1.0 breakdown)
Explanation: IRC:106 (Guidelines for Capacity of Urban Roads): LOS A–F. India uses Volume/Capacity (V/C) ratio as primary criterion: LOS A (V/C < 0.35): free flow; LOS B (0.35–0.55): stable; LOS C (0.55–0.77): stable; LOS D (0.77–0.90): approaching unstable; LOS E (0.90–1.0): unstable; LOS F (> 1.0): forced/breakdown. Also considers speed and travel time. PCU (Passenger Car Unit) used to convert mixed traffic to equivalent cars.
- 33Transportation EngineeringEASY
The 'PMGSY' (Pradhan Mantri Gram Sadak Yojana) aims to provide:
AFour-lane expressways in rural areasBAll-weather road connectivity to unconnected rural habitations — single-lane bituminous, 3.75 m carriagewayCUrban ring roads around citiesDOnly river bridges with no roadAnswer: B. All-weather road connectivity to unconnected rural habitations — single-lane bituminous, 3.75 m carriageway
Explanation: PMGSY: Pradhan Mantri Gram Sadak Yojana (2000). Goal: all-weather road connectivity to unconnected rural habitations. Targets: Phase I — 500+ population (plain); Phase II — 250+ population habitations; Phase III — consolidation and upgradation. Technical: single-lane bituminous road (3.75 m carriageway), drainage, cross-drainage structures. Funded: central government 90%, states 10%. Implemented through NRRDA. Significant improvement in rural connectivity.
- 34Transportation EngineeringMEDIUM
The 'grade compensation' on horizontal curves for railways and highways means:
AIncreasing gradient on curves to compensate for slower speedsBReducing ruling gradient on horizontal curves to compensate for centrifugal force that effectively steepens the gradeCAdding extra width to carriageway on curvesDOnly increasing super elevation without grade changeAnswer: B. Reducing ruling gradient on horizontal curves to compensate for centrifugal force that effectively steepens the grade
Explanation: Grade compensation (IRC:38 / RDSO): on sharp horizontal curves, maximum permissible gradient is REDUCED because: centrifugal force + grade force = combined effect reduces effective tractive force and increases braking requirement. Compensation: reduce ruling gradient by: (1) 30/R % for roads (R in m); (2) 0.04% per degree of curve for railways (IR). Otherwise vehicles struggle on combined grade + curve.
- 35Transportation EngineeringMEDIUM
The 'intersection angle' of a horizontal curve (deflection angle Δ) is related to the total deflection by:
AΔ = radius of curveBT = R×tan(Δ/2); arc L = R×Δ(rad); tangent length and arc length are both functions of R and ΔCΔ is only relevant for vertical curvesDNo relation — Δ is independent of geometryAnswer: B. T = R×tan(Δ/2); arc L = R×Δ(rad); tangent length and arc length are both functions of R and Δ
Explanation: Intersection angle Δ: angle between back tangent and forward tangent at PI (point of intersection) = total change in direction. Tangent length T = R × tan(Δ/2). Length of arc L = RΔ (Δ in radians) = πRΔ/180 (Δ in degrees). Chord C = 2R×sin(Δ/2). Long chord direction = bisects Δ. Deflection angle from tangent to any point on curve = half the subtended angle.
- 36Transportation EngineeringMEDIUM
The 'axle load' restriction on Indian National Highways for trucks is:
ANo axle load limit exists in IndiaB6.5 t single axle (2 wheels), 10.2 t single axle (4 wheels), 19 t tandem axle — CMVR limitsC100 tonnes per axleD2 tonnes per axle maximumAnswer: B. 6.5 t single axle (2 wheels), 10.2 t single axle (4 wheels), 19 t tandem axle — CMVR limits
Explanation: Motor Vehicles Act 1988 / CMVR: maximum axle loads — Single axle (2 wheels): 6.5 t; Single axle (4 wheels = tandem): 10.2 t; Tandem axle (2 axles): 19 t; Tridem axle: 24 t. Total vehicle weight limit: 2-axle truck 16 t; 3-axle 25 t; multi-axle 49.5 t (with special permit for heavier loads). Overloading causes premature pavement failure. Weigh-in-motion (WIM) systems used for enforcement.
- 37Transportation EngineeringMEDIUM
The 'right of way' (ROW) for a National Highway as per NHAI/IRC standards is:
A10 m for all National HighwaysB45 m (2-lane), 60 m (4-lane), 90 m (6-lane) for National Highways in plains as per IRC standardsCOnly 5 m on each side of roadDAs decided locally by each stateAnswer: B. 45 m (2-lane), 60 m (4-lane), 90 m (6-lane) for National Highways in plains as per IRC standards
Explanation: ROW for National Highways: 4-lane divided (NH): ROW = 60 m in plains; 6-lane = 90 m. 2-lane NH: 45 m. Expressway: 90–120 m ROW. ROW includes: carriageway, median, shoulders, drains, service road, utility corridor. ROW is reserved land for future expansion. NHAI acquires ROW under NHAI Act/NHAA 1956. Urban NH may have reduced ROW due to constraints.
- 38Transportation EngineeringMEDIUM
The 'design capacity' of a metro (heavy rail) system per track per hour is approximately:
A200 passengers per hourB40,000–80,000 PPHPD — high capacity enabled by exclusive alignment, high frequency, and long trainsCSame as regular bus (5000 PPHPD)D2,000 PPHPD onlyAnswer: B. 40,000–80,000 PPHPD — high capacity enabled by exclusive alignment, high frequency, and long trains
Explanation: Metro/Heavy rail capacity: 40,000–80,000 passengers per hour per direction (PPHPD). Depends on: train length (6–8 cars), car capacity (1500–2000 passengers/train), headway (2–3 minutes). Delhi Metro: 36,000 PPHPD (Phase I/II). Bus PPHPD: 4000–8000. BRT PPHPD: 4000–10,000. Metro justified above 20,000–30,000 PPHPD. LRT: 10,000–20,000 PPHPD.
- 39Transportation EngineeringMEDIUM
The 'Flexible pavement' design method IRC:37-2018 is based on:
AOnly CBR chart from 1970sBMechanistic-empirical method: cumulative ESALs + subgrade CBR + layer resilient modulus → strain criteria for rutting and fatigueCOnly concrete design (no bitumen layers)DPavement failure by earthquake loadingAnswer: B. Mechanistic-empirical method: cumulative ESALs + subgrade CBR + layer resilient modulus → strain criteria for rutting and fatigue
Explanation: IRC:37-2018 (3rd revision): mechanistic-empirical design using: (1) Cumulative traffic in MSA (million standard axles); (2) Subgrade CBR (from lab test); (3) Material characterisation (resilient modulus of each layer); (4) Critical responses — vertical compressive strain at subgrade top (rutting) and horizontal tensile strain at bituminous layer bottom (fatigue cracking). Uses IITPAVE software for stress analysis. Replaces old CBR-thickness chart method.
- 40Transportation EngineeringMEDIUM
The 'Equivalent Single Axle Load' (ESAL) concept is used in pavement design to:
AMeasure the size of tyre contact areaBConvert all axle loads to damage equivalent of standard 80-kN axle using 4th power law for pavement thickness designCCount the number of vehiclesDMeasure total traffic in km drivenAnswer: B. Convert all axle loads to damage equivalent of standard 80-kN axle using 4th power law for pavement thickness design
Explanation: ESAL: converts all axle loads to equivalent passes of an 80-kN (18-kip) standard single axle using damage factor = (axle load/80 kN)^4 (4th power law). Allows comparison of pavement damage from different axle configurations (single, tandem, tridem). Total design ESALs = sum over design period = basis for structural design in both IRC:37 (flexible) and IRC:58 (rigid).
- 41Transportation EngineeringMEDIUM
The 'Intergreen time' at a traffic signal is the time between:
APeak hour and off-peak hourBEnd of green of one phase and start of green of next — amber/all-red time to clear conflicting vehicles from intersectionCMorning and evening peak periodsDTwo consecutive green phases on the same approachAnswer: B. End of green of one phase and start of green of next — amber/all-red time to clear conflicting vehicles from intersection
Explanation: Intergreen (clearance) time = all-red + amber time. Purpose: clear vehicles that entered intersection during end of green. Calculation: IG = t_perception + clearance time from last entry point. Includes amber (orange) phase (typically 3–5 s for vehicles to stop or proceed). All-red ensures no conflict. Effective green = green + amber − start loss.
- 42Transportation EngineeringMEDIUM
The 'critical lane volume' in traffic signal design is defined as:
ATotal volume on all approachesBHighest lane volume in each phase — governs green time allocation; sum across phases (Y) determines cycle lengthCOnly pedestrian crossing volumeDVolume at the end of the green phaseAnswer: B. Highest lane volume in each phase — governs green time allocation; sum across phases (Y) determines cycle length
Explanation: Critical lane volume: maximum lane volume among all lanes moving during one phase. For each phase: critical volume = volume of lane that controls green time (highest demand). Sum of critical volumes (y = v/s, v=volume, s=saturation flow) across phases (Y = Σy) determines cycle length and is measure of intersection loading. Oversaturation when Y > 0.9.
- 43Transportation EngineeringHARD
Corrugations in flexible pavement are:
ALoss of rail ballastBTransverse undulations at fairly regular intervalsCSettlement of bridge bearingDLongitudinal cracks onlyAnswer: B. Transverse undulations at fairly regular intervals
Explanation: Stop-and-go traffic and unstable mix can create washboard-like waves.
- 44Transportation EngineeringEASY
PCU in traffic engineering stands for:
APlasticity Correction UnitBPassenger Car UnitCPavement Camber UnitDPeak Capacity UseAnswer: B. Passenger Car Unit
Explanation: PCU converts mixed traffic into equivalent passenger cars.
- 45Rigid Pavement JointMEDIUM
Dowel bars at transverse expansion joints in rigid (cement concrete) pavement primarily:
AAct as reinforcement for the slabBTransfer loads between adjacent slabs while allowing longitudinal movement (expansion/contraction)CPrevent warpingDMark the joint locationAnswer: B. Transfer loads between adjacent slabs while allowing longitudinal movement (expansion/contraction)
Explanation: Dowel bars (smooth, round, coated with debonding agent on one side) transfer shear across transverse joints while allowing longitudinal thermal movement. Tie bars (at longitudinal joints) are deformed bars that prevent separation of slabs but do NOT allow movement.
- 46PCU FactorMEDIUM
The Passenger Car Unit (PCU) for a two-axle truck on an Indian highway (as per IRC) is approximately:
A1.0B2.0C3.0D4.5Answer: B. 2.0
Explanation: IRC SP 41 PCU values: Passenger car = 1.0; two-axle truck/bus = 2.0; three-axle truck = 3.0; motorcycle = 0.5; cycle = 0.5; bullock cart = 8.0. PCU converts mixed traffic to equivalent passenger car units for capacity analysis.
- 47Airport Runway OrientationMEDIUM
The orientation of an airport runway is determined by:
APrevailing wind directionBWind rose analysis to maximize wind coverage (percentage of time crosswind component < permissible limit)CSun angleDTerrain onlyAnswer: B. Wind rose analysis to maximize wind coverage (percentage of time crosswind component < permissible limit)
Explanation: Runway orientation is chosen using wind rose analysis so that aircraft can take off/land with acceptable crosswind components (< 20 km/h for small aircraft, < 37 km/h for large aircraft) for maximum percentage of time (usually 95%). The most favourable wind direction = lowest crosswind.
- 48Aggregate Impact ValueMEDIUM
The Aggregate Impact Value (AIV) test determines:
AResistance of aggregate to abrasionBToughness (resistance of aggregate to sudden impact)CWater absorption of aggregateDFlakiness of aggregateAnswer: B. Toughness (resistance of aggregate to sudden impact)
Explanation: AIV (IS 2386 Part 4): sample of aggregate is subjected to 15 blows of a standard hammer. AIV = (weight of fines passing 2.36 mm sieve / total weight) x 100%. AIV < 10%: exceptionally strong; 10-20%: strong; 20-30%: satisfactory; > 35%: weak.
- 49Pavement Failure ModesMEDIUM
Rutting in flexible pavements is a permanent deformation primarily caused by:
AFatigue cracking of bituminous layersBPlastic deformation of subgrade or bituminous layers under repeated heavy axle loads in hot weatherCReflection cracking from base layerDFrost heaveAnswer: B. Plastic deformation of subgrade or bituminous layers under repeated heavy axle loads in hot weather
Explanation: Rutting = longitudinal groove in wheel path due to accumulation of plastic deformation in any/all pavement layers (mainly bituminous mix and subgrade). Causes: overloading, high temperature (soft bitumen), insufficient pavement thickness, poor mix design.
- 50Highway DrainageMEDIUM
The camber (cross-slope) provided on road surface in the transverse direction is primarily to:
AIncrease the pavement strengthBDrain rainwater off the road surface quicklyCIncrease the riding comfortDCompensate for superelevation on curvesAnswer: B. Drain rainwater off the road surface quickly
Explanation: Camber (crown) = transverse slope from the centerline to the edge, typically 2-3% for bituminous roads and 2.5-3% for gravel/WBM. It ensures surface water drains to the edge quickly, preventing waterlogging which weakens the pavement.