TTENG 422 Traffic Operations Module 3 S2024.pdf

Traffic and lane management

2. | Lane Management
V4

4. Lane Management

| What is Managed Lanes?

| It can be defined as a combination of operational and design
actions that meet local and regional mobility objectives.

/ The overall goals of managed lanes are:
YA Improve traffic operations (better LOS)
Facilitate movement of people and goods (better LOS)

Enhance performance and efficiency (better LOS)
Promote air quality goals (Minimize congestion)
Improve safety

5. | Lane Management

Lane management Examples:
HOV lanes
| High-occupancy/Toll (HOT) lanes

Dynamic shoulder lanes
y Express lanes
VL Lane Reversal
Truck lanes
Interchange bypass lanes (usually transit, HOV or truck only)

Dual roadways in which at least one of the roadways is
managed

Separate express lane tollways constructed within freeways

6. Lane Management

Examples: High Occupancy Vehicles(HOV) Lane

E p ol

7. Lane Management

Examples: Shoulder Use

!

use end use of leave
hard shoulder hard shoulder hard shoulder

8. | Lane Management Examples: Lane Reversal

9. Lane Management Examples: Lane Reversal

10. Lane Management Examples: Lane Reversal

12. Lane Management Examples: Lane Reversal

13. Lane Management Strategies

Occupancy restrictions

Vehicle type restrictions (e.g.. buses, vanpools, taxis, carpools)
Access

Express lanes with limited access

/ Contratlow lanes

Reversible lanes
Ramp and mainline metering

Pricing
Decal or sticker registration for use
Congestion pricing on managed lanes

Fixed or variable electronic tolling

14. Lane Management Strategy

Lane Management

Pricing

Vehicle
Eligibility

Access
Control

Value Priced Lanes
Toll Lanes HOT Lanes
HOV Lanes Multifaceted
Truck Lane Restrictions Managed Lane
Use of HOV lanes by Facilities
other vehicle group

Incorporates

multiple lane

management
strategies

Increasing complexity with active management 3

individuals

15. Lane Management Strategies

Active traffic management (ATM), generally represented as traffic control
applications that promote safer and more efficient operations, can be
used to support the above strategies.

Examples include
Speed advisories and controls
Dynamic lane assignment
Dynamic hard shoulder running

Dynamic route diversion

16. Lane Management: Context of Application

| The supporting rational might be one or more of the following:

| A mobility policy that encourages commute choices
Aneed to allocate limited spatial resources to a higher and better level of performance.

An inability to manage the lane(s) or roadway through more conventional strategies.

A willingness to segregate and prioritize some lanes to meet a variety of regional goals,

A lack of other options for more conventionally expanding capacity among one or more
transportation modes

A desire to flexibly address demand over time due to changing traffic and corridor
conditions, often beyond the respective project design year

A need for the respective project to cover some of its operation and implementation cost
due largely to limited funding.

17. | Lane Management: Determining Operational
Needs
Demand:
Demand for a single dedicated lane needs to meet two thresholds:

| 1. Enough near-term “opening year” minimum demand needs to exist to
| support public acceptance, and

2. Demand for the longer-term should be present to justify

implementation.
J

The thresholds for demand can vary by concept and by the two
timelines indicated.

18. Lane Management: Determining Operational
Needs

Capacity:
Due to limited capacity: there is aneed to manage demand to ensure
maximum utilization of limited capacity
Managing demand does not mean allowing the lane to reach its vehicle
carrying capacity.
Managing flow below capacity can better assure travel benefits.
For Single lane , the maximum managed flow threshold of approximately
1600 to 1650 vehicles/hour/lane (vphpl)

Multi-lane treatments may obtain somewhat higher values approaching
1700 to 1900 vphpl

19. Lane Management: Determining Operational
Needs

Capacity:

LOS F=1400
vph/lane at 25
mph

LOS. C:1600,vph/lane at.60 mph

20. Lane Management: Determining Operational
Needs

Corridor and System Context :

managed lanes may be only appropriate at a corridor level in a
| region where congestion is limited in duration and extent on the
| region's freeway system

In larger areas where traffic congestion is systemic to the freeway
network and may regularly recur for many hours, a regional context
/ to determining operational needs may be appropriate

21. Lane Management: Anticipated Benefits

| Provide more mobility options.

Promote and sustain transit service

Reduce dependence on single occupant travel by promoting ridesharing
Enhanced travel reliability.

Address air quality

Improve safety
Enhance trucking and commerce.

Augment transportation funding & Generate revenue.
Improve user information

Expand throughput

Reduce travel delay.

22. | Case Studies:
| Lane Reversal Assessment
Va

A

23. Impact of Lane Reversal on Highway Capacity & LOS
Operational Case: Existing Facility

Design Input:

Multilane Highway

Number of Lanes = 6 (both directions)
Lane Width = 3.2m

Median = yes

spoulders =0.6

Traffic Volume = 41000 AADT ( K =0.14, D=0.65 )
Topography (i.e. Terrain: Rolling

HV% = 12%, PHF= 0.90, BFFS = 70 km/hr
Design Objective:

Improving Current Level Of Service (LOS)

24. | Case Studies:

\ HOV Lane Assessment
| /

|

25. HOV Lane Feasibility Assessment: Example

Data: Evaluate the addition of HOV lane to a given freeway
Lane width = 3.40 m , #lanes = 6 (3 in each direction) PHF = 0.90
Truck% = 0 % (Trucks are not allowed during peak hours)

Basic Free Flow Speed (BFFS) = 100 km/hr,

Current Volume = 4860 veh/hr , Lateral Clearance = 1.2 m (Right) &
0.6m (Left)

Interchange density = 0.5 interchange/ km
Occupancy Rate Survey Data:

Current: 1 person > 79%, 2 p. > 18%, 3+ py? 12%
Expected: 1 person 3,58%, 2 p. > 20%, 3+ p. > 22%

Estimate the new LOS for the HOV traffic and the average LOS
for the freeway

26. |

| / End of Module 3