Concept explainers
The capacity of the lane group.
Answer to Problem 5P
The capacity of the lane group is
Explanation of Solution
Given:
The base rate is
Lane width is
Heavy vehicles are
Approach grade is
No on-street parking.
No bus stops.
Bicycle and pedestrian traffic conflicting with this lane group is negligible.
Intersection is in a central business district.
The effective green time for the movement is
The total cycle length is
Formula used:
The adjusted saturated flow rate for a lane group is given by
Here,
The Heavy-vehicle adjustment factor is given by
Here,
The grade adjustment factor is given by
Here,
Parking adjustment factor is given by
Here,
The bus blockage adjustment factor is given by
Here,
The lane utilization adjustment factor is given by
Here,
The right turn adjustment factor for protecting movement on exclusive lane is given by
Here,
The left turn adjustment factor for protecting movement on exclusive lane is given by
Here,
The value of
The capacity of the lane group is given by
Here,
Calculation:
The Heavy-vehicle adjustment factor is calculated as
Substitute
The grade adjustment factor is calculated as
Substitute
Parking adjustment factor is calculated as
Substitute
The bus blockage adjustment factor is calculated as
Substitute
The right turn adjustment factor for protecting movement on exclusive lane is calculated as
Substitute
The left turn adjustment factor for protecting movement on exclusive lane is calculated as
Substitute
The adjusted saturated flow rate for a lane group is calculated as
Substitute
The capacity of the lane group is calculated as
Substitute
Conclusion:
The capacity of the lane group is
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Chapter 10 Solutions
MindTap Engineering for Garber/Hoel's Traffic and Highway Engineering, 5th Edition, [Instant Access], 1 term (6 months)
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