Grade changes in the centerline of streets with an algebraic difference in grades of more than one percent (1.00%) shall be connected with vertical curves. Vertical curve design shall be based on the equation:
L = KA Where
L = length of curve in feet
K = factor defined by the table below
A = algebraic difference in grade
In any case, the street grades and vertical curves shall be such that the sight distance is not less than six hundred (600) feet on main thoroughfares, and not less than four hundred (400) feet on all other streets.
CLASSIFICATION | MINIMUM VERTICAL GRADE, % | MAXIMUM VERTICAL GRADE, % | MINIMUM LENGTH OF CURVE, L | CREST,K VALUE | SAG, K VALUE |
CLASSIFICATION | MINIMUM VERTICAL GRADE, % | MAXIMUM VERTICAL GRADE, % | MINIMUM LENGTH OF CURVE, L | CREST,K VALUE | SAG, K VALUE |
Major Thoroughfare | 0.50% | 6.00% | * | * | * |
Normal Thoroughfare | 0.50% | 6.00% | * | * | * |
Arterial | 0.50% | 6.00% | 150' | 145 | 100 |
Collector | 0.50% | 8.00% | 125' | 100 | 80 |
Major Residential | 0.50% | 10.00% | 100' | 30 | 35 |
Minor Residential | 0.50% | 12.00% | 100' | 10 | 15 |
*As approved by City Engineer based on actual design parameters. | |||||