Re: Six lane underground rail lines

From: habshi (habshi_at_anony.com)
Date: 01/02/05 

Date: Sun, 02 Jan 2005 21:44:04 GMT

        The only way to separate the trucks is to put them on rail
wagons underground. If Paris can buld 70 miles of six lane underground
highways for cars , why cant the US and India build 5000 miles for
just trains which takes up a lot less space ?

excerpts
http://www.rppi.org/ps250.html
C. Metroroutes--Lower-Cost Auto Tunnels

The French have gone furthest in systematically studying car/truck
separation because of their determination to improve mobility inside
Paris. Acquiring space for surface motorways and gaining acceptance of
elevated structures were so unlikely that the French were led to look
carefully at high-cost underground construction. In 1987 Francois
Lemperiere of the GTM engineering company was credited with the idea
of using a 34-foot (10m) diameter tunnel which could normally house
just two lanes of roadway for unrestricted-size vehicles to provide a
three-fold increase in capacity. He showed a design for using the same
tube to provide two levels with three lanes each level for vehicles of
six foot seven (2m) maximum height in lanes of about ten-foot (3m)
wide (see Figure 3). He pointed out that this tripled vehicle-carrying
capacity could transform the prospect of financing underground urban
toll motorways. Out of Lemperiere's conceptual proposal came a
government-organized commission to study safety issues and work to
produce specifications for light-vehicle underground road networks.

In June 1992 the Center for the Study of Tunnels (CETU), central
government officials, and city officials from Paris and Nice produced
specifications translated as Recommendations on Reduced Height Urban
Tunnels (known by the acronym RECTUR) suggesting three standards for
what have come to be called "metroroutes." The name was a take from
"Metro," the name of the Paris subway. Gerondeau and others saw this
as a possible system or network of underground roads that could be
applied under major cities to supplement and link together currently
unconnected surface motorways.

GTM was credited with the idea of using a 34-foot (10m) diameter
tunnel which could normally house just two lanes of roadway for
unrestricted-size vehicles to provide a three-fold increase in
capacity.

The three vehicle height standards set by RECTUR were:

Six foot seven (2.0m), which covers 85 percent of vehicle types in the
Paris region excluding minibuses in which passengers can stand, and
all existing emergency vehicles;
Eight foot ten (2.7m), which allows most ambulances and the minibuses;

Eleven and a half feet (3.5m) allows urban buses and most fire
equipment, but not heavy trucks or long-distance coaches.
RECTUR recommended 20 inches (55cm) above the height of the highest
allowable vehicle for hanging signs and for psychological comfort, so
in the case of 2m-max vehicle tunnels the ceiling would be at eight
foot four (2.55m.) The committee also researched the lane width needs
and offsets from walls. Cofiroute decided on the six foot seven (2m)
standard for its six-mile toll tunnel for the A-86 West project in
Versailles. Cofiroute found the benefits of the larger dimensions did
not come near the extra costs. Special low-height emergency vehicles
will be built. The company estimates that in rush hours, when such a
toll facility will be in greatest demand, well over 90 percent of
potential traffic will fit into the six foot seven (2m) gauge of the
tunnel portals. It estimates the tunnel's six lanes will carry up to
8,000 vehicles/hour and average daily traffic of 100,000. Posted speed
limit will be 70km/hr (43 mph) with automated speed ticketing at
80km/hr (50 mph). The tight dimensions will encourage this kind of low
average speed driving, but the lower speed also maximizes vehicle
throughput and is considered likely to produce safe travel. Another
cost saving in excluding heavy vehicles is the ability to design for
steep grades and tighter curves, especially helpful in reducing costs
of ramps at interchanges. A maximum grade of 12 percent was specified
by the RECTUR report.

The A-86 West small gauge tunnel will use air ducts, separate for each
level. In case of fire or accidents stairways will allow motorists to
use the alternate level as refuge from smoke, and emergency services
will be able to block off the other level and operate from there.
Cofiroute officials have said they will probably begin operations of
the tunnel with only two travel lanes on each level with the third as
breakdown buffer area and merge/diverge lane at interchanges, but may
run all three lanes if traffic is heavy. Estimated cost of the whole
project is now $2 billion or $360m/mile. This is about an 80 percent
cost increase as compared to estimates made when the franchise was
granted, though Cofiroute insists it remains financially viable.

The Paris regional plan for 2015 lays out 62-miles of metroroutes, and
they have also been considered for a new motorway to the Roissy
Charles de Gaulle Airport, and as additional capacity for the southern
part of the Boulevard Peripherique or inner ring road. Metroroutes
seem to have considerable potential in a number of large dense
European cities, especially in London. In the United States they would
seem to be most applicable in developed areas with high land values
and local antagonism to the

"We have to get the trucks out of lanes in which cars travel. This is
the only way to make the major highways safe for small vehicles such
as cars." --James Ball, Transportation International

The Pennsylvania Turnpike, which runs 25,000 heavy trucks a day (out
of a total of 75,000 vehicles daily), has examined what it called a
"dual/dual" concept, a 2/2/2/2 lane profile in which two lanes in each
direction would be for heavy trucks and two for light vehicles, but so
long as there are free parallel interstates for trucks (I-80 in the
north of the state, and I-68 just south in Maryland) it seems unlikely
to be a financially viable idea. John Hickey, manager of research for
the turnpike, says giving heavy trucks separate roadways is a very
attractive idea. He says that many motorists in their cars feel
extremely uncomfortable on the four-lane turnpike driving right
alongside heavy trucks, especially in bad weather when the trucks'
tires spray their windshields with great showers of dirty water as
they pass. The sheer size of trucks intimidates many car drivers, and
Hickey thinks the turnpike loses car patrons because of the heavy
concentration of trucks in its present mixed-vehicle

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