Sub-problem 4a: Potential Left-Turn Capacity
Step 1. Setup
We will now look at the operation of the northbound left-turn movement and consider the potential left-turn capacity of that movement as it crosses the eastbound movement.
Exhibit 3-26 shows the northbound left-turn queue at the Okeechobee Road Intersection. Observe the number of heavy vehicles in the traffic stream.
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Exhibit 3-26. Northbound Left Turn |
The heavy northbound congestion evident in the current operation (see Exhibit 3-26) suggests that the capacity of the northbound left turn should first be examined by the basic principles set forth in the HCM before the full procedure is invoked by software. This step will give us a better understanding of the basic relationships that apply to TWSC control.
Consider:
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What volume-related factors affect the northbound left-turn movement capacity?
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What geometry-related factors affect the northbound left-turn movement capacity?
- How could we take into account the separation of the roadways?
Discussion:
Take
a few minutes to consider these questions. Click continue when you are
ready to proceed.