CE 474 Class 17. October 1, 2015

Transcription

1 CE 474 Class 7 October, 05

2

3 Excel Skills Parse text data file into columns Manipulate rows and columns of data Sort data by criterion (criteria) Use logical (if) statements Create frequency data from raw data Create frequency plots VISSIM Skills Increase demand on link Set signal timing parameters Set data collection point Select/configure data collection evaluation file Statistical Skills Create and interpret frequency plots Transportation Concepts/Knowledge Define Maximum Allowable Headway (MAH) Define types of phase termination (and desirability of each) Distinguish between queued and nonqueued vehicles Select MAH, trading competing (type, type ) risks, using phase termination analysis (PTA) results Describe concept of PTA and components of process Relate PT to MAH

4 Determine the MAH and Passage Time balancing: Phase failure, initial queue not served (Type ) Inefficient extension of green (Type ) 4

5 5

6 6

7 t(leave) VehNo Headway t(exit)

8 Frequency Headway Frequency Headway (sec) Queued Headway Free-flow Headway Non-Queued Headway 8

9 Headway, sec MAH=s MAH=s Vehicle number in departing queue 9

10 Headway, sec 6 5 MAH=s 4 MAH=s Vehicle number in departing queue 0

11 Headway, sec 6 MAH=s 5 4 MAH=s Vehicle number in departing queue

12 Task

13 Task

14 Tab Description Deliverables A6 Title page with activity number and title, authors, and date completed. Raw data from the MER file. Parsed data, headway data, and frequency data and plot. 4 Phase termination analysis using template including summary table containing number of occurrences of each termination type. 5 Evaluation of phase termination analysis including discussion of results from Task 5, selection of and justification for MAH, and determination of passage time. 6 Performance data from VISSIM. 7 Analysis and summary of VISSIM performance data including comparison of new data and observations with results from the base case (Activity #8). 4

15 Task 5

16 If(tQueue>0, Q, NQ ) Task 6

17 Task 7

18 Task 4 8

19 Percentage of total 5% 0% 5% Queued vehicles 0% Non-queued vehicles 5% 0% Headway, sec Task 4 9

20 Task 5 0

21 Task 5

22 First cycle Second cycle Here is an example of two consecutive sets of queued and non-queued data ready for the phase termination analysis.

23 First cycle Second cycle Note that the first two queued headways (in red boxes) are large. These are actually not realistically headways as they really represent the time from the last vehicle departing from the previous cycle to the first vehicle departing from the current cycle.

24 In this figure, we ve now eliminated these two very large headways

25 Task 5 5

26 Other slides 6

27 t(leave) VehNo Q or NQ Headway Q Q Q Q Q Q NQ NQ NQ NQ NQ NQ NQ NQ 0.7 7

28 8

29 Headway (sec) Queue Free-Flow Why blank? 9

30 Headway (sec) Queue Free-Flow Queued Data Non-Queued Data Bin Frequency %Frequency %CumulativeFreq Bin Frequency %Frequency %CumulativeFreq

31 Frequency Headway (sec) Queue Free-Flow 0.5 Headway Frequency Queued Data 0.4 Non-Queued Data Bin Frequency %Frequency %CumulativeFreq Bin Frequency %Frequency %CumulativeFreq Headway (sec) Queued Headway Free-flow Headway

32 Frequency Frequency Headway (sec) Queue Free-Flow 0.5 Headway Frequency Queued Data 0.4 Non-Queued Data.8 Bin Frequency %Frequency %CumulativeFreq Bin Frequency %Frequency %CumulativeFreq Cumulative 5 Headway 0.69 Frequency Headway (sec) Queued Headway Free-flow Headway Headway (sec) Queued Headway Free-flow Headway

33 Headway (sec) Signal Information Outcomes Queue Free-Flow Ideal Signal Display Change Occurs Type Good Type.95 G.58 G.8 G.56 G.7 R Change.9 R.5 R.6 R.67 R.7 R 0.9 R.9 R.87 R

34 Headway (sec) Signal Information Outcomes Queue Free-Flow Ideal Signal Display Change Occurs Type Good Type.95 G.58 G.8 G.56 G.7 R Change.9 R.5 R.6 R.67 R.7 R 0.9 R.9 R.87 R Outcome Distrubution Error Type 7 Good Error Type Outcome Summary Conclusion Percentiles 97th (Optimal) 95th 85th 75th Headway (sec) Error Type Good Error Type 4

35 Headway, sec Time

36 Headway, sec Time

37 Headway, sec Time Type : Green extends too long

38 Headway, sec Time Type : Green ends too early

39 Headway, sec Time Type : Green ends too early Type : Green extends too long