Chapter 1360
Interchanges
WSDOT Design Manual M 22-01.20
Page 1360-24
September 2021
Exhibit 1360-15 On-Connection: Single-Lane, Tapered
Notes:
[1] For acceleration lane length LA, see Exhibit 1360-10.
[2]
Point
A
is the point controlling the ramp design speed.
[3] A transition curve with a minimum radius of 3000 ft is desirable. The desirable length is 300 ft. When
the main line is on a curve to the left, the transition may vary from a 3000-ft radius to tangent to the
main line.
[4] Radius may be reduced when concrete barrier is placed between the ramp and main line.
[5] Lane and shoulder widths are shown for illustrative purposes. For ramp lane and shoulder widths,
see Exhibit 1360-6.
[6] Approximate angle to establish ramp alignment.
General:
For striping, see the
Standard Plans
.