TRANSPORTATION MODELING

Transcription

1 TRANSPORTATION MODELING

2 Modeling Concept Model Tools and media to reflect and simple a measured reality. Types of Model Physical Model Map and Chart Model Statistics and mathematical Models MODEL?

3 Physical Model

4 Map Model (Desire Line)

5 Map Model

6 Chart Model

7 Chart Model

8 Statistic and Mathematical Models

9 What is the final goal of designing model? What is variables considered? What is variables that influenced and arranged by planner? What is the theory? How grouping model level? How the role of time? What kind of data that available? How about the calibration and validity?

10 Objectives Help to understanding how the system working Predicted the changes in land use and transport infrastructure system The main variables Land Use Transportation Infrastructure System Traffic flow Parameters that can be set Land Use RTRW, RDTRK, etc. Transportation Infrastructure Tatranas, Tatrawil, Tatralok, etc.

11 Theory/ Concept Accessibility Generated and Attracted Trip Trip Distribution Mode choice Route choice Dynamic Traffic Flow Grouping Level Areas? Combining and Grouping traffic flow? Time Static Model Dynamic Model

12 Scope Mathematical, statistical, operational research, programming Data Quantity Quality Calibration and Validation Calibration : process of assessing the parameter value of a model with various techniques (numerical analysis, linear algebra, optimization, etc.) Validation : expected models with calibrated parameters before it produce the same output with reality (data) forecasting future Modification : Reduction or addition of several variables suit for the applications in the area or another condition.

13 Determination of the study area Study area divided into several zones, numbers and areas depend on level of accuracy expected The Outside of study area divided into several external zones to reflect the other zones

14 System activities simplified in the zone form and considered to represented by the central zone Internal Zone the zone that located in studies area have major contribution to the movement that occurred External Zone the zone that located outside study area have small contribution to movement occurred Central Zone virtual point that representing the center activity zone, the beginning and the ending of the movement to another zone

15 Network system that simplified in road and joint form Road segment or railway network, etc. The segment must have information of road conditions Node intersection, station, city, etc. Activity and Network systems was connected with central zone Central Zone Link virtual segment that connected to the central zone (activity system) by a node (network system)

16 1 2 Internal Zone Central Zone 4 3 Border Study Study area 5 6

17 gateway Road Node Border area Study area

18 Zone center link Border area Study area 5 6

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20 Combined Cost Concept Combining three main components of route choice (Distance, cost, time) Combined cost of private cars Gcp = yd + utv + C Where : Gcp = Combined cost for PC (Rp) y = Operating vehicle cost per unit distance (Rp/km) C = parking cost, toll, etc.

21 Combined cost for public transport: G cu = fd + u T a + u T w + u T v + d Where : Gcu D Ta Tw Tv minutes) f u d = Combined cost for PT (Rp) = Distance (distance unit, e.g : km) = walking time (time unit, e.g: minutes) = waiting time PT (time unit, e.g: minutes) = time in public transportation (time unit, e.g: = cost per distance (Rp/km) = time value per unit time (Rp/minutes) = surcharge unmeasured

22 A Simple Model of Land Use / Transport System Objectives: Help to understand how the transportation system works Predict the changes in traffic flows which will result from changes to land use or to the transport system Variables: Land Use System : population and employment Transport system : Distance, Travel time Traffic System

23 Notasi: L A,B P A A B = Land Use in Zone A, B = Traffic Generation from zone A = Traffic Attraction to zone B Q AB(1) = Traffic from zone A to zone B using route 1 T Q AB(1) = Travel time from zone A to zone B using in traffic condition is Q T 0 = Travel time in free-flow traffic = 0 C = Road capacity a = Level of Service index

24 Traffic Generation P A = f (L A ) A B = f (L B ) Traffic Distribution Q AB = P A.A B.k T QAB Mode and Route Choice T QAB(1) = T QAB(2)

25 Activity system : Zone Land Use Population Information A Residential % working age B Employment area Transport characteristic: Route Length (km) To (min.) Los Index (a) Capacity (veh/h) , , , Traffic Distribution Q AB = P A.A B.0,001 T QAB

26 1. The amount of traffic from zone A to zone B if only route 1 that operated? 2. The amount of traffic from zone A to zone B if only route 2 that operated? 3. The amount of traffic from zone A to zone B if route 1 and 2 operating together? 4. The amount of traffic if adding a new road 3 and route 1,2, and 3 are operated together? 5. The amount of traffic if there are changes in residential population become and employment population ?

27 Solution Demand Equation: Q AB = x x 0,001 T QAB = T QAB

28 Supply Equation: Route 1: Route 2: Route 3: T QAB(1) = 25 x ( Q AB(1) ) Q AB(1) T QAB(2) = 40 x Q AB(2) T QAB(3) = 20 x ( Q AB(3) ) Q AB(3)

29 Analytical method If only route 1 that operated: T QAB(1) = Then: Q AB(1) ( Q AB(1) ) x Q AB(1) = (3.000 Q AB(1) ) x Q 2 AB(1) Q AB(1) = 0 Q AB(1) = Q AB(1) = (>>C 1 ) Q AB(1) = veh/h T QAB(1) = 137,2 minutes

30 If only route 2 that operated: T QAB(2) = Q AB(2) x Q AB(2) = (2.000 Q AB(2) ) x Q AB(2) = 0 Q AB(2) = veh/h T QAB(2) = 229 minutes

31 If route 1+2 operating together: Limit 1: Q AB = Q AB(1) + Q AB(2) Limit 2: T QAB = T QAB(1) = T QAB(2) Equal condition 1 and 2: T QAB = = Q AB Q AB(1) +Q AB(2) (1)

32 Equ.(1) Limit 2: T QAB = T QAB(2) = Q AB(1) +Q AB(2) Q AB(2) Q AB(2) = Q AB(1) Q AB(2) Q AB(1) = ,725 Q AB(2) (2)

33 Limit 2: T QAB(1) = T QAB(2) QAB(1) = Q AB(1) Q AB(2) Q AB(2) Q AB(1) 15Q AB(1) Q AB(2) = Q AB(1) Q AB(1) 15Q AB(1) Q AB(2) Q AB(2) = (2)

34 Substitution (1) to (2): ( ,725 Q AB(2) ) 15 ( ,725 Q AB(2) ) Q AB(2) Q AB(2) = ,875Q AB(2) Q AB(2) = 0 (3) Obtainable: Q AB(2) = Q AB(2) = (-, impossible) Then : Q AB(2) = veh/h T QAB(2) = 98,675 mins. Q AB(1) = veh/h T QAB(1) = 98,675 mins. Q AB = veh/h T QAB = 98,675 mins.

35 If route operating together: Limit 1: Q AB = Q AB(1) + Q AB(2) + Q AB(3) Limit 2: T QAB = T QAB(1) = T QAB(2) = T QAB(3) Limit 1: T QAB = = Q AB Q AB(1) +Q AB(2) +Q AB(3) (1)

36 Graphical method From the equation demand and supply, input value of Q AB to obtain value of T QAB, T QAB(1), T QAB(2) or T QAB(3) Plot the value of Q AB and T QAB, to obtain the demand curve Plot the value of Q AB and T QAB(1), T QAB(2) or T QAB(3) to obtain supply curve route 1, 2 and 3 Cutting point between demand and supply curve is a equilibrium point

37 QAB Demand TQAB 0 ~ Supply QAB TQAB(1) TQAB(2) TQAB(3) ~ ~ ~

38 T (Travel time- minutes) Relationship between Q AB and T QAB Demand Supply 1 Supply 2 Supply 3 0 Q (Vehicle per hour)

39 T (Travel time, minutes) Relationship between Q AB and T QAB Demand Supply 1 Supply 2 Supply 3 Supply 1+2 Supply Q (Vehicle per hour)

40 T (Travel time, minutes) Relationship between Q AB and T QAB Demand Supply 1 Supply 2 Supply 3 Supply 1+2 Supply Demand Baru Q (vehicle per hour)

41 Assignment Transportation Characteristic: Route Length (km) To (minutes) LoS index (a) Capacity (veh/h) , , Another data same with example before

42 Complete with analytical method: 1. The amount of traffic from zone A to zone B if only route 1 that operated? 2. The amount of traffic from zone A to zone B if only route 2 that operated? 3. The amount of traffic from zone A to zone B if route 1 and 2 operating together?