FACULTY OF CIVIL AND ENVIRONMENTAL ENGINEERING DEPARTMENT OF GEOTECHNICAL AND TRANSPORTATION ENGINEERING TRAFFIC AND TRANSPORTA TRANSPORTATION TION TRANSPORTATI ON ENGINEERING LABORATORY
LABORATORY REPORT Subject Code Lab Work Title
TR3 – SIGNALIZED INTERSECTION LEVEL OF SERVICE ANALYSIS
Course Date of Lab Work Name of Student Group Name of
1.
Group Members
2. 3. 4. 5.
Name of Instructor Marks
Attendance & Discipline
/ 10%
Involvement
/ 15%
Data Analysis
/ 30%
Results
/ 25%
Discussion & Conclusion
/ 20%
TOTAL
/ 100% Stamp of Receipt:
Faculty: Faculty of Civil and Environmental Engineering Department : Department of Geotechnical and Transportation Engineering Title: SIGNALIZED INTERSECTION LEVEL OF SERVICE ANALYSIS 1.0
INTRODUCTION The capacity of a street is related primarily to the signal timing and the geometric characteristics of the facility as well as to the composition of traffic on the facility. Geometrics are a fixed characteristic of a facility. Thus, while traffic composition may vary somewhat over time, the capacity of a facility is generally a stable value that can be significantly improved only by initiating geometric improvements. At signalized intersections, the additional element of time allocation is introduced into the concept of capacity. A traffic signal essentially allocates time among conflicting traffic movements that seek to use the same space. The way in which time is allocated significantly affects the operation and the capacity of the intersection and its approaches. In analyzing a signalized intersection, the physical unit of analysis is the lane group. A lane group consists of one or more lanes on an intersection approach. The outputs from application of the method in this manual are reported on the basis of each lane group. Capacity at intersections is defined for each lane group. The lane group capacity is the maximum hourly rate at which vehicles can reasonably be expected to pass through the intersection under prevailing traffic, roadway, and signalization conditions. Capacity is stated in vehicles per hour (veh/h). The level of service (LOS) at signalized intersections is expressed in terms of delay, which relate to control, geometrics, traffic and incidents. Stopped delay may be used to determine the LOS. It is defined as the time a vehicle waits at a traffic light. Stopped delay is stated in seconds per vehicle (sec/veh).
2.0
OBJECTIVE The objective is to determine the capacity and level of service of the UTHM intersection using JKR Arahan Teknik (Jalan) 13/87 procedure.
Prepared by: Name: Basil David Daniel Date: 1 November 2007
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Faculty: Faculty of Civil and Environmental Engineering Department : Department of Geotechnical and Transportation Engineering Title: SIGNALIZED INTERSECTION LEVEL OF SERVICE ANALYSIS 3.0
4.0
APPARATUS / EQUIPMENT 1.
Measuring Tape / Odometer
2.
Stopwatch
3.
Analog Counter (optional)
4.
Safety Vest
5.
Safety Cones
6.
Flags
PROCEDURE 1.
Conduct a traffic movement count at each approach for one hour in segments of 15 minutes. Record the data in Tables 1 – 6.
2.
Measure the lane width, W (in meter) for each approach and record the data in Table 7.
3.
For each phase, measure the green time, g (sec) and cycle time, C (sec). Record the data in Table 8.
4.
Convert traffic volumes recorded in Tables 1 – 6 to passenger car unit (p.c.u.). This is taken as the design flow, q (pcu/hr) which will then be used in Table 7.
5.
Determine the saturation flow, S (pcu/hr) for each approach and transfer the values to Table 7.
6.
Using Table 7, compute y , which is the ratio of design flow to saturation flow and determine theY value, which is the total value of y for each approach.
7.
Then, calculate the intergreen time, I (sec) and total lost time per cycle L (sec),
8.
Determine the practical capacity, Y prac and reserve capacity, RC of the intersection.
9.
Determine the average stopped delay per vehicle, d (sec) and level of service for each approach.
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Faculty: Faculty of Civil and Environmental Engineering Department : Department of Geotechnical and Transportation Engineering Title: SIGNALIZED INTERSECTION LEVEL OF SERVICE ANALYSIS 5.0
DATA ANALYSIS & RESULTS Table 1 Location: PARIT RAJA APPROACH (THROUGH) Day: __________________ Date: __________________ Time: _____________ Weather: _______________ Time
Traffic Count Vehicle Class 1
2
Vehicle Class
3
Traffic Volume (veh/hour)
Class 1 (Motorcycles) Class 2 (Cars) Class 3 (Vans & Medium Trucks) Class 4 (Heavy Trucks & Buses)
4
p.c.u. Factor 0.33 1.00 1.75 2.25
p.c.u.
Total Note: p.c.u. = passenger car unit
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Faculty: Faculty of Civil and Environmental Engineering Department : Department of Geotechnical and Transportation Engineering Title: SIGNALIZED INTERSECTION LEVEL OF SERVICE ANALYSIS Table 2 Location: PARIT RAJA APPROACH (RIGHT TURN) Day: _________________ Date: __________________ Time: _____________ Weather: _______________ Time
Traffic Count Vehicle Class 1
2
Vehicle Class
3
Traffic Volume (veh/hour)
Class 1 (Motorcycles) Class 2 (Cars) Class 3 (Vans & Medium Trucks) Class 4 (Heavy Trucks & Buses)
4
p.c.u. Factor 0.33 1.00 1.75 2.25
p.c.u.
Total Note: p.c.u. = passenger car unit
4
Faculty: Faculty of Civil and Environmental Engineering Department : Department of Geotechnical and Transportation Engineering Title: SIGNALIZED INTERSECTION LEVEL OF SERVICE ANALYSIS Table 3 Location: UTHM APPROACH (LEFT TURN) Day: __________________ Date: __________________ Time: _____________ Weather: _______________ Time
Traffic Count Vehicle Class 1
2
Vehicle Class
3
Traffic Volume (veh/hour)
Class 1 (Motorcycles) Class 2 (Cars) Class 3 (Vans & Medium Trucks) Class 4 (Heavy Trucks & Buses)
4
p.c.u. Factor 0.33 1.00 1.75 2.25
p.c.u.
Total Note: p.c.u. = passenger car unit
5
Faculty: Faculty of Civil and Environmental Engineering Department : Department of Geotechnical and Transportation Engineering Title: SIGNALIZED INTERSECTION LEVEL OF SERVICE ANALYSIS Table 4 Location: UTHM APPROACH (RIGHT TURN) Day: __________________ Date: __________________ Time: _____________ Weather: _______________ Time
Traffic Count Vehicle Class 1
2
Vehicle Class
3
Traffic Volume (veh/hour)
Class 1 (Motorcycles) Class 2 (Cars) Class 3 (Vans & Medium Trucks) Class 4 (Heavy Trucks & Buses)
4
p.c.u. Factor 0.33 1.00 1.75 2.25
p.c.u.
Total Note: p.c.u. = passenger car unit
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Faculty: Faculty of Civil and Environmental Engineering Department : Department of Geotechnical and Transportation Engineering Title: SIGNALIZED INTERSECTION LEVEL OF SERVICE ANALYSIS Table 5 Location: BATU PAHAT APPROACH (THROUGH) Day: __________________ Date: __________________ Time: _____________ Weather: _______________ Time
Traffic Count Vehicle Class 1
2
Vehicle Class
3
Traffic Volume (veh/hour)
Class 1 (Motorcycles) Class 2 (Cars) Class 3 (Vans & Medium Trucks) Class 4 (Heavy Trucks & Buses)
4
p.c.u. Factor 0.33 1.00 1.75 2.25
p.c.u.
Total Note: p.c.u. = passenger car unit
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Faculty: Faculty of Civil and Environmental Engineering Department : Department of Geotechnical and Transportation Engineering Title: SIGNALIZED INTERSECTION LEVEL OF SERVICE ANALYSIS Table 6 Location: BATU PAHAT APPROACH (LEFT TURN) Day: __________________ Date: __________________ Time: _____________ Weather: _______________ Time
Traffic Count Vehicle Class 1
2
Vehicle Class
3
Traffic Volume (veh/hour)
Class 1 (Motorcycles) Class 2 (Cars) Class 3 (Vans & Medium Trucks) Class 4 (Heavy Trucks & Buses)
4
p.c.u. Factor 0.33 1.00 1.75 2.25
p.c.u.
Total Note: p.c.u. = passenger car unit
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Faculty: Faculty of Civil and Environmental Engineering Department : Department of Geotechnical and Transportation Engineering Title: SIGNALIZED INTERSECTION LEVEL OF SERVICE ANALYSIS Table 7 Phase Diagram
Movement W (m) S *(pcu/hr) q (pcu/hr) y = q/S y
1
PRThrough
2
BPTh+Left
PRThrough
3
PRRight
KLeft
KRight
* Saturation flow (S) must be corrected for effect of gradient, turning radius, left-turn and right-turn (whichever required). * Assume turning radius for this intersection is between 10 – 15 m.
Example Calculation of Saturation Flow, S
Y = y 1 + y 2 + y 3 =
(Note: Y must be 0.85 or below, in order to proceed with calculations.) Amber time, a = 3 sec All-red period, R = 2 sec Intergreen time, I = a + R = Drivers’ reaction time, l = 2 sec Number of phases, n = 3 Total lost time, L = n(I – a) + nl =
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Faculty: Faculty of Civil and Environmental Engineering Department : Department of Geotechnical and Transportation Engineering Title: SIGNALIZED INTERSECTION LEVEL OF SERVICE ANALYSIS
Practical capacity, Y prac = 0.9 – 0.0075L =
Reserve capacity, RC = 100% × ( Y prac – Y ) / Y =
Table 9 Phase Movement C (sec)
1 PRThrough
2 BPTh+Left
PRThrough
3 PRRight
KLeft
KRight
g (sec) λ =
g/C
S (pcu/hr) q (pcu/hr) qs(pcu/sec) x = q/λ S d (sec) LOS
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Faculty: Faculty of Civil and Environmental Engineering Department : Department of Geotechnical and Transportation Engineering Title: SIGNALIZED INTERSECTION LEVEL OF SERVICE ANALYSIS Example calculation for delay and determination of LOS
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Faculty: Faculty of Civil and Environmental Engineering Department : Department of Geotechnical and Transportation Engineering Title: SIGNALIZED INTERSECTION LEVEL OF SERVICE ANALYSIS 6.0
DISCUSSION Comment on the LOS of UTHM intersection? Based on the LOS, do you think the intersection needs to be upgraded? Why? What upgrading is required?
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Faculty: Faculty of Civil and Environmental Engineering Department : Department of Geotechnical and Transportation Engineering Title: SIGNALIZED INTERSECTION LEVEL OF SERVICE ANALYSIS 7.0
CONCLUSION
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Faculty: Faculty of Civil and Environmental Engineering Department : Department of Geotechnical and Transportation Engineering Title: SIGNALIZED INTERSECTION LEVEL OF SERVICE ANALYSIS 8.0
APPENDIX (A) Saturation Flow Estimation If W < 5.5 m, use the following table: W (m) S (pcu/hr)
3.0 1845
3.25 1860
3.5 1885
3.75 1915
4.0 1965
4.25 2075
4.5 2210
4.75 2375
5.0 2560
5.25 2760
If W ≥ 5.5 m, use the equation S = 525W
(B) Saturation Flow Adjustment Sadj = S × F g × F r × F l × F t Correction factor for the effect of gradient, F g is taken as 1.00 for 0% gradient. Correction factor for the effect of turning radius, F t Correction Factor, F t Description 0.85 for turning radius R < 10 m 0.90 for turning radius where 10 m < R < 15 m 0.96 for turning radius where 15 m < R < 30 m Correction factors for turning traffic, F r and F l % Turning Traffic Factor for right-turn, F r 5 0.96 10 0.93 15 0.90 20 0.87 25 0.84 30 0.82 35 0.79 40 0.77 45 0.75 50 0.73 55 0.71 60 0.69
Factor for left-turn, F l 1.00 1.00 0.99 0.98 0.97 0.95 0.94 0.93 0.92 0.91 0.90 0.89
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Faculty: Faculty of Civil and Environmental Engineering Department : Department of Geotechnical and Transportation Engineering Title: SIGNALIZED INTERSECTION LEVEL OF SERVICE ANALYSIS (C) Average Stopped Delay per Vehicle Average delay per vehicle, d on a particular intersection arm is given by the formula:
d =
2 9 C (1 − λ )
10 2(1 − λ x )
+
2qs (1 − x ) x
2
where C = cycle time (sec) λ = proportion of the cycle that is effectively green for the phase = g/C qs = flow in pcu/sec x = degree of saturation = q/λ S
(D) Level of Service Criteria for Signalized Intersection LEVEL OF SERVICE DELAY PER VEHICLE A < 5.0 seconds B 5.1 to 15.0 seconds C 15.1 to 25.0 seconds D 25.1 to 40.0 seconds E 40.1 to 60.0 seconds F > 60.0 seconds Source: JKR ATJ 13/87 (E) UTHM Intersection Layout
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