Civil Engineering Reference
In-Depth Information
Fig. 17.1
Growth rate in traf
c versus growth rate in roadway capacity (1982
-
2010) and its
impact on traf
c congestion.
Source
Reference [
3
], p 16, Exhibit 11
Roadway Widening and Reconstruction
New Roadways
New Toll Roads
Examples of strategies that apply to
priority vehicles
include:
Managed Lanes (HOV, HOT, Express Toll/Value Pricing)
Truck-only Lanes
Intermodal Access Roads
A summary assessment of these various strategies, developed by Cambridge
Systematics and Resource System Group [
2
], is shown in Table
17.1
.
The remainder of this chapter describes new capacity enhancement strategies
that apply to all vehicles and priority vehicles. It also sets forth some consequences
in the application of these strategies such as the
“
induced traf
c
”
issue of added
capacity.
17.2 Capacity Expansion for All Vehicles
The traditional approach to capacity expansion has been to eliminate congestion for
all roadway users by highway bottleneck removal, intersection reconstruction and
expansion, widening existing roads, and building new roadways. Collectively these
capacity expansion actions have generally reduced congestion and increased
mobility.
