UNIT V 1. What are the traffic management measures? [N/D-13] Some of the well-known traffic management measures are: a) Restrictions on turning movements b) One - way streets c) Tidal - flow operations d) Exclusive bus lanes e) Closing side streets 2. What is Transportation System Management (TSM)? [N/D-14] Transportation System Management (TSM) is a package of short term measures to make the most productive and cost - effective use of existing transportation facilities, services and modes. 3. List out the various types of Travel Demand Management (TDM) techniques. [N/D-13] The following are some of the techniques of Travel Demand Management (TDM): a) Car pooling and other ride-sharing programmes b) Peripheral parking schemes c) Road pricing d) Entry fee e) Priority for buses in traffic. f) Restriction on entry of trucks during day time 4. What is period of forecasting? [N/D-13] Since the traffic forecasting is needed for transport plans, the design period selected for transport plans should be sufficient for traffic forecasting. In general, transport plans are for a period of about 5 to 10 years in detail and an additional five years in less detail. In U.K., it is customary to forecast traffic for a design period of 15 years when dealing with rural roads. In India, National Highways are designed for 15 years after completion of work. 5. What is Aggregate and Disaggregate Models in Traffic Forecasting? [N/D-13] Aggregate models deal with the estimation of travel of a group of travellers. Disaggregate models deal with the smallest decision making unit, the individual traveller. 6. What is the purpose of one - way streets? [N/D-14] One-way streets provide the most immediate and the least expensive method of controlling the traffic conditions in a busy area. In combination with other methods such as banned turning movements, installation of signals and restrictions on loading and waiting, the one-way street system is able to achieve great improvement in traffic congested areas. 7. What are the disadvantages of one - way streets? [N/D-13] The disadvantages of one - way streets are: a) Although the journey times and delays are reduced, the actual distances to be covered by drivers increases b) Where buses operate on the streets, the stops will have to be relocated and in many instances the passengers will have to walk extra distances c) In the initial stages of introduction of one-way streets, confusion is likely to be created amongst motorists and pedestrians
8. Write any two advantages of closing side streets. [N/D-13] The advantages of closing side streets are: a) Since interference from the traffic from side streets is eliminated, the speed increases, journey time reduces and accidents reduces b) The side - streets which are closed can be utilised for parking of vehicles, if there is an acute shortage of parking space in the area 9. What is meant by traffic regulations? [N/D-14] The traffic regulations should cover all aspects of control of vehicles, driver and all other road users. The regulations should be rational. Traffic regulations and laws give legal coverage for strict enforcement. Traffic regulations and laws cover the following four phases: a) Driver controls b) Vehicle controls c) Flow regulations d) General controls 10. Define - Traffic Calming [N/D-13] Traffic calming consists of physical design and other measures for the intention of reducing the motor vehicle speed as well as to improve the safety of pedestrians and cyclists. Traffic calming includes the engineering measures such as: a) Narrowing traffic lanes b) Speed bumps c) Speed humps d) Speed cushions e) Speed tables 11. What is meant by tidal flow operation in Traffic Management? [N/D-14] The morning peak results in a heavy attraction of flow towards the city centre, whereas the evening peak brings in heavier flow away from the city centre. In either case, the street space provided for the opposing traffic will be found to be in excess. This phenomenon is called as Tidal flow. One method of dealing with the problem of tidal flow is to allot more than half the lanes for one direction during peak hours. This system is known as Tidal flow operation, or Reverse flow operation. 12. What is meant by Exclusive Bus Lanes? Exclusive bus lane is provided by reserving a lane of the carriageway exclusively for bus traffic. This is possible only in situations where the carriageway is of adequate width and a lane can be easily spared for the buses. This implies that there should be atleast 3 lanes in each direction. For reasons of convenience of alighting and embarking passengers at the curb, the exclusive bus lane has to be adjacent to the curb. 13. What are the uses of exclusive bus lanes in road traffic? [N/D-14] The following are some of the uses of exclusive bus lanes in road traffic: a) The journey time of buses can be considerably reduced b) Bus journey can be made more attractive c) Regularity of buses can be improved 14. Define ITS [N/D-14] Intelligent Transport Systems (ITS), also known as Transport Telematics, are transport systems that apply modern information technologies to improve the operation of transport networks. The ITS acquires vast volume of data on various aspects of transport operation (such as traffic volume, speed, headway), process them and apply the result to guide traffic, improve operations, enhance safety and transport costs.
15. List out the uses of ITS in traffic engineering. [N/D-13] ITS can cover a wide variety of application such as: a) Monitoring traffic flow b) Monitoring incidents on the road c) Traffic control on urban roads d) Public Transport Management Systems e) Electronic collection of toll f) Electronic Road Pricing System 16.List our various travel demand management techniques. [N/D-16] Car pooling and other ride-sharing programmes Peripheral parking schemes Road pricing Entry fee Priority for buses in traffic. Restriction on entry of trucks during day time 17.What are the applications of intelligent transport system? Monitoring traffic flow Monitoring incidents on the road Traffic control on urban roads Public Transport Management Systems Electronic collection of toll Electronic Road Pricing System [N/D-16]
PART-II 1.Write in detail the methods of forecasting in traffic volume prediction. All-or-nothing assignment method [N/D-16] Direction curve method Capacity restraint assignment techniques Multi-route assignment technique All-or-nothing This is the simplest technique, in which all trips for a zone are assigned the minimum path connecting the nodes. The minimum path is the route which has the least travel time, travel cost or distance. The technique assumes that the capacity of each link is infinite so that the volume of traffic does not affect the time of travel or cost of travel. In the first stage, the network description and tree building is made. The next stage is to assign the traffic flows to the minimum path tree. Direction curve Diversion curves method is one of the frequently used assignment techniques. This method predicts the percentage of trips that is likely to use a proposed new facility (bypass, new expressway, new arterial street, etc.) based on distance saved or time saved or cost saved. The data collected from the pattern of road usage in the past serve to build up such curves. Diversion curves can be constructed using the following variables:- 1. Travel time saved 2. Distance saved 3. Travel time ratio 4. Distance ratio 5. Travel time and distance saved 6. Travel cost ratio 7. Distance and speed ratio
Capacity restraint The capacity restrained assignment technique involves a sequence of all-or-nothing minimum path assignments where the sequence is iterated until the traffic volumes assigned to each links are comparable with the link travel time assumed in the minimum path tree building phase. The link travel time used in assignment is a function of speed on that link, which again is independent on the traffic flow being assigned. Because of the iterative nature of the calculation involved this technique is carried out entirely by computers. Multi-route All road users may not be able to judge the minimum path for themselves. It may also happen that all road users may not have the same criteria for judging the shortest route. These limitations of tall-or-nothing approach are recognised in the multiple route assignment technique. The method consists of assigning the interzonal flow to a series of routes, the proportion of the total flow assigned to each being a function of the length of that route in relation to the shortest route. Mclaughlin developed one multipath traffic assignment technique as under: A driver's route selection criteria is used which is a function of :- (i) (ii) (iii) Travel time Travel cost Accident potential
2. Discuss in detail the traffic management measures as per IRC standards. [N/D-16] Area Licensing Scheme a. 1970s Singapore experienced rapid growth b. Traffic volume was especially high during peak hours c. Government made plans to manage traffic before it became too serious Area Licensing Scheme d. Area Licensing Scheme (ALS) introduced e. Motorists had to pay for use of certain roads f. Roads bounded within areas designated as Restricted Zones g. Gantries set up to monitor motorists Area Licensing Scheme h. To support ALS, other measure introduced i. Improving bus services ii. Increasing cost of parking city areas iii. Providing park-and-ride facilities i. When ALS started, motorists were unhappy j. However ALS reduced the number of cars k. Overall, ALS was successful in ensuring smooth traffic flow