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From page 46... ... 46 This section includes strategies to optimize traffic flow through the work zone corridor and adjacent roadways using various traffic operations techniques and technologies. The following strategies are covered in this section: • Lane merge systems • Reversible lanes • Ramp metering • Truck-lane restrictions 3.1 Lane Merge Systems 3.1.1 Description Lane merge systems refer to the lane-use instructions that inform motorists of the merge point location during a lane closure. Read the entire page →
From page 47... ... Corridor/Network Management Strategies 47 • Speeds and lane occupancy volumes are anticipated to vary unpredictably and cause the motorist to have trouble identifying the best lane-use practice, such as using both lanes versus moving into the continuous thru-lane. Figure 3.3 shows a flowchart developed by ATSSA (2012) Read the entire page →
From page 48... ... 48 Strategies for Work Zone Transportation Management Plans 3.1.3 Benefits The use of an early-merge system provides the following benefits: • Reduces aggressive driving and unsafe merge maneuvers. • Provides significant advanced warning to allow drivers adequate distance to merge. Read the entire page →
From page 49... ... Corridor/Network Management Strategies 49 Figure 3.4. Static (passive) Read the entire page →
From page 50... ... 50 Strategies for Work Zone Transportation Management Plans Figure 3.5. Dynamic late-merge (i.e., zipper merge) Read the entire page →
From page 51... ... Corridor/Network Management Strategies 51 It is pertinent to ensure that the PCMS is displaying reasonable messages. The PCMS should be located in advance of the lane closure as determined by the engineer based on estimated queue lengths and geometry. Read the entire page →
From page 52... ... 52 Strategies for Work Zone Transportation Management Plans queues for only 35 minutes, and for weeks 7–9, that location saw queues for 76 minutes. Data for weeks 10–12 was skewed because of another work zone operation that involved a lane closure. Read the entire page →
From page 53... ... Corridor/Network Management Strategies 53 In general, the rental cost is the same for a PCMS or a traffic sensor or camera -- approximately $1,000 per week. For longer-duration projects, the rental costs can be substantially lower. Read the entire page →
From page 54... ... 54 Strategies for Work Zone Transportation Management Plans 3.2 Reversible Lanes 3.2.1 Description A reversible roadway is one in which the direction of traffic flow in one or more lanes or shoulders is reversed to the opposite direction for some period of time. Its utility is derived by taking advantage of the unused capacity of the minor-flow direction to increase capacity in the major-flow direction, thereby negating the need to construct additional lanes. Read the entire page →
From page 55... ... Corridor/Network Management Strategies 55 3.2.6 Implementation Considerations The ITE Traffic Engineering Handbook (7th edition) recommends that DOTs examine the following criteria before implementing reversible lanes: • The traffic congestion problem under investigation should be both periodic and predictable. Read the entire page →
From page 56... ... 56 Strategies for Work Zone Transportation Management Plans MUTCD (Figure 6H-45) shows a typical application using moveable barriers for a temporary reversible lane. Read the entire page →
From page 57... ... Corridor/Network Management Strategies 57 peak hour traffic. The moveable barrier was moved twice daily, which allowed contractors to maintain two open lanes of travel during peak volumes (two lanes southbound in the morning and two lanes northbound in the afternoon) Read the entire page →
From page 58... ... 58 Strategies for Work Zone Transportation Management Plans barriers to separate directional traffic would mean restricting traffic to a 3/2 pattern through the duration of the $46 million project. Instead, MDOT used a reversible lane to keep three lanes open in the peak direction at all times while retaining positive barrier protection between opposing traffic lanes. Read the entire page →
From page 59... ... Corridor/Network Management Strategies 59 eastbound pavement in 2017. During the 2017 season, a reversible lane using moveable barriers allowed contractors to maintain four lanes of travel open during peak volumes (four lanes westbound in the morning and four lanes eastbound in the afternoon) Read the entire page →
From page 60... ... 60 Strategies for Work Zone Transportation Management Plans 3.2.10 Resources and References CDOT. I-70 Mountain Corridor CSS, I-70 Reversible Lane -- Phase II Feasibility Study, Colorado Department of Transportation, February 2011. Read the entire page →
From page 61... ... Corridor/Network Management Strategies 61 Figure 3.11. Temporary ramp-metering layout (Credit: MnDOT) Read the entire page →
From page 62... ... 62 Strategies for Work Zone Transportation Management Plans For the work zone ramp meter to be effective, the recommendation is that the combined vehicular volume on the main line and the ramp not exceed 1,600 vphpl (ramp volumes not to exceed 400–600 vphpl) Read the entire page →
From page 63... ... Corridor/Network Management Strategies 63 Ramp geometry is often a barrier to implementing ramp metering. Agencies should ensure the acceleration lane and storage can accommodate queues resulting from a metered traffic setup. Read the entire page →
From page 64... ... 64 Strategies for Work Zone Transportation Management Plans 3.3.10 Resources and References Arnold, E Read the entire page →
From page 65... ... Corridor/Network Management Strategies 65 3.4.2 When to Use Conditions most conducive to favorable application of truck-lane restrictions are • Roadways with two or more lanes in each direction. • Interchanges spaced more than 2 mi apart with low ramp volumes. Read the entire page →
From page 66... ... 66 Strategies for Work Zone Transportation Management Plans 3.4.7 Design Features and Requirements Truck-lane restrictions are typically achieved by using stand-alone static signs (TRUCKS USE LEFT/RIGHT LANE [2009 MUTCD R4-5] Read the entire page →
From page 67... ... Corridor/Network Management Strategies 67 truck use to the left lane to keep trucks off shoulders that were not repaired. Trucks were restricted to left-lane use in both the northbound and the southbound directions. Read the entire page →

From page 46...

... 46 This section includes strategies to optimize traffic flow through the work zone corridor and adjacent roadways using various traffic operations techniques and technologies. The following strategies are covered in this section: • Lane merge systems • Reversible lanes • Ramp metering • Truck-lane restrictions 3.1 Lane Merge Systems 3.1.1 Description Lane merge systems refer to the lane-use instructions that inform motorists of the merge point location during a lane closure.