Traffic Solutions Evolution Of The 2pi

Metropolitan Traffic CorporationPresents:

The Super Street Concept“Two Phase At-Grade System”

Copyright 2003 MetTra Corp.

Arthur Hale’s CloverleafAASHTO

Copyright © 2002 Belisario H. Romo / Mettracorp. All rights reserved.

Belisario H. Romo’s

The Problem TodayCan we afford to wait?

Today, in our mobility oriented

world, serious congestion and

gridlock is widespread.

The ideal “freeway” mode has

disappeared!

Most freeways are saturated, and

they are indeed NOT free. Ideally

vehicles should ride freely,

without delays from entrance to

exit.

The clogged freeway is

frustrating. Everybody knows is

cramped and slow, but, WHY?.....


Failed example to solve mobility

The Katy Freeway is congested

more than 11 hours per

weekday, usually in both

directions.

Morning rush hour averages

16 mph.

It is already so slow that

people avoid it!

This is the result of injecting 60

percent of the traffic onto 2

percent of road surface!

At this rate there will be no city left to go to.

Motorists became disenchanted with the freeway

dream.


Analysis…

At rush hours 60

percent of traffic is

force into 2 percent

of freeways road

surface.

The streets, 98% of

road surface, works

at 25% capacity.

There is a traffic

light at the entrance

or exit of a freeway

ramp.


Analysis…

For decades traffic engineers have

transplanted the design philosophies

developed for intercity freeways to the

quite different conditions of the city.

Were new design criteria is essential.

Requirements of high speed design truly

do not apply to urban areas.

Saving time by increasing speed is not

relevant in urban traffic conditions

because average trip distance is

significantly shorter.



Speed 5 Mile Trip 10 Mile Trip

mph (in minutes) (in minutes)

5 60 120

10 30 60

15 20 40

20 15 30

30 10 20

35 51.4 8.6 102.7 17.1

40 7.5 15

45 6.7 13.3

50 6 12

55 5.5 10.9

60 5 10

65 4.6 9.2

70 4.3 8.6

75 4 8

80 4.8 3.8 9.6 7.5

Tra

ve

l Tim

es

Sa

vin

gs

(in m

inu

tes

)

Tra

ve

l Tim

es

Sa

vin

gs

(in m

inu

tes

)

Tra

ve

l Tim

es

Sa

vin

gs

Only…

……

.

Tra

ve

l Tim

es

Sa

vin

gs

On

ly……

….

Increasing average

speeds from 5 mph

to 35 mph on an 5

mile trip would save

51.4 minutes travel

time.

Increasing average

speeds from 35

mph to 80 mph will

reduce travel time

by only 4.8 minutes.

Urban freeways, reduce travel time by insignificant amounts, take decades

to complete, decimates the city and create gridlock by concentrating the

bulk of traffic in less road surface (2%.)

Better returns can be obtained by investing these massive sums in more

advanced designs snatching back the full capacity of the other 98% of

available road surface, the streets network, thus obtaining greater benefit

to cost ratio and increase capacity for the new millennium.

We at Metropolitan Traffic Corporation concluded that in order to achieve

sustainable mobility in urban areas, one goal has to be meet. Solve the

simple street crossing. The basic cell of the network.

We succeeded!Copyright © 2002 Belisario H. Romo / Mettracorp. All rights reserved.


In the beginning our main objective was to

improve the highway interchange.

Reducing the number of levels required to

obtain 4 left turns and the 4 trough traffic.

Save land and reduce significantly the cost to

almost 40%

We succeeded!

We manage to produce a design that only

requires 2 levels to obtain all movements

required.

Saves 30% of the land required by the 4

leveled design

And more importantly saves cost and time to

implement it.


It was only natural to scale the highway

interchange to obtain this concept.

We finally were able to offer a complete

featured interchange within the urban

network of streets.

The City of Phoenix, Az., order us to evaluate

this conceptual design for the Camelback

Road corridor.

Although mechanically efficient the cost

remain a concern when a number of

intersections were considered.

It was at this point, that, in an effort to reduce

the cost we decided to manage the left turns

with traffic lights controls instead of

depressed access ramps.

The result was…………… unexpected! Copyright © 2002 Belisario H. Romo / Mettracorp. All rights reserved.

This flattened interchange became the most efficient traffic design ever to

solve the nemesis of traffic: the left turns !

In fact we found that it was feasible to operate with only two phases per

cycle in a same plane. By parallelizing and synchronizing 2 trough traffics,

2 left turns, 2 right turns and 2 pedestrian movements per phase.

Reducing the number of phases at the intersection also allows to operate

the intersection at maximum capacity.

Among other benefits:

Reduces atmospheric emissions and noise. Cleaner air.

Increases capacity by 100% at the intersections.

Coordination and synchronization is greatly improved.

Cycles are shorter delay are reduced to a few seconds.

Pedestrians are safer enjoying full phase to cross.

Can be implemented in record time, is economical, urban and

environmental friendly.

Improves property values. No structures are necessary.

Corridors can be upgrade to work in two phases: The Super Street ! Copyright © 2002 Belisario H. Romo / Mettracorp. All rights reserved.


The technology to avoid gridlock exist. Putting it

together to solve traffic congestion requires

geometrical innovations at the intersections.

Mode separation is required primarily to achieve:Organized traffic operations

Systemic multimodal connections.

More capacity out of the network of city streets.

Efficient detection, control and management.

The mixing of transportation modes is a major contributor in the

generation of gridlock. Mass transit systems, private transportation

and cargo are incompatibles because:

Operative Speed

Turning radius

Required stops

Size

Passenger number


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Traffic Solutions Evolution Of The 2pi