Introduction
Development of land for use involves Infrastructure development like road, rail, sea and air transport systems, with suitable terminals for embarking and disembarking of passengers and other passenger support systems like catering, rest rooms, warehouses, etc. Sustainability of these transport systems is an important issue, in general. With Urban economic development there is a possibility of the local vernacular culture being threatened. There are certain tools developed which would be suitable for preserving this local culture. The three types of anchors which preserve the vernacular culture are (1):
1. Markets
2. Ethnic areas
3. Heritage sites
It is also important to preserve or improve the Ecology of the area being exploited for economic development. The present modular design concept developed for road networks, is independent of type of development be it Rural or urban community developments.
Motor Vehicle Traffic congestion and environmental effects
An Urban environment entropy model has been successfully proposed for urbanization environmental impact assessment (2). Substantial increase in urban population, household incomes, and industrial and commercial activities are the cause of urban transportation chaos in many countries like India. Studies made for building suitable future city growth prediction models for the Indian subcontinent are interesting(3).
Solutions proposed in such studies mainly aim at reducing owner driven motor vehicles and congestion by
1. Encouraging use of public transport
2. Building new mass transport systems like Metro Maglev etc.
3. Widening exiting roads and building new ones.
None of the above options are sustainable, as in no time the number of Motor Vehicles tend to overtake the increased capacity of the infrastructure.
The case for non motor Vehicle transport (NMVT)
Conventional urban land development planning practices often consider walking and cycling as minor transport modes, which leads to a planning bias (4). Mobility normally includes a walking link at both at start and end of daily commuting in every person’s life. This start and end transport link should be pleasant, non-irritating, healthy, safe and in a clean environment devoid of any pollutants. This link is an important factor in encouraging people to the use of public transport.
The pedestrians, cyclists and hawkers are a neglected lot due to lack of lobbying for infrastructure for this mode of transport. This option is a viable and effectively combative to the unchallenged motor vehicles lobby. Thus providing safe, healthy and conducive green atmosphere infrastructure for NMVT can be an effective MV Transport systems sustainability tool.
Often the question “Whose Roads” (5) is put by many people who believe that non motorized modes (Walking and cycling) have an inferior right to use the public road compared with motor vehicles. However since motor vehicles impose significant risk on pedestrians and cyclists, it is prudent to segregate them from motor vehicles traffic by having separate foot paths, cycling and hawker tracks. As majority of roads are developed and maintained by general taxes, it is worth while to allocate portion of these funds to development of exclusive foot paths and cycling cum hawker tracks. It is necessary to include Hawkers in the category of cyclists in 3rd world countries (6) like India.
A case for Greenery
The carbon foot print of the motor vehicles needs to be compensated by good green area ratios. It is a good policy to have enough greenery to alleviate the damage caused by motor vehicles not only due to their carbon emissions but also due to the road asphalting related ecological damage. The roads, foot paths and cycling tracks need to be surrounded by greenery, to maintain or improve the ecology of the terain. This green belt which houses the foot paths and cycling tracks has to be planned in parallel along with any road networking existing or newly planned.
A case for signal free MV Road Network
It is not uncommon for genuine apprehensions like
1. A signal free road may result in a nightmarish traffic.
2. The number of vehicles will always increase and eventually succeed in defeating any move for a signal free road network.
3. There should be more signals to control traffic!
4. Signal free means no control possible over traffic!
While the apprehensions are genuine, perhaps they should not exclude any attempt to visualize and design a road net work which is signal free for a given MV density pattern in a city. It is possible to estimate the number of vehicles which could ply comfortable in any stretch of a given road at a given speed, at any instant of time.
The Aim
With the above considerations we propose to develop a new signal free modular road network design concept for a vernacular land development with active segregation of Pedestrian and non motor transport like cycling and hawking carts. A network consisting of major and minor arterial roads are dealt with in the proposed design.
The Various Stages in the growth of a city
The Early days
Normally the traffic in any road is in dual direction, one direction being the opposite of that of the other. The dual way traffic is a default option due, to the freedom of movement it provides. However this initial freedom could be a potential bottleneck, for any organized growth in land connectivity. Unless this phenomenon is well understood and enough care is taken to avoid such bottle necks in future any city development will be an unpleasant endeavor.
A city Road Infrastructure is planned for an expected sprawl of the city and the expected traffic density applicable to each of its main boulevards, in fairly foreseeable time at the time of conception. L Kempegowda (7) the founder of the city of Bangalore in India, for example had erected Four Towers to mark the expected growth of the city of Bangalore, when he laid the foundation stone of the city, in early 16th century. The city crossed these limits in a couple of centuries.
Mature days
When the traffic density increases beyond the early design limits, regulating the dual way traffic in the existing main boulevards in the older parts of the city becomes unmanageable.
1. More and more curbs on the traffic by way of introducing one ways
2. Manual Traffic regulation
3. Introduction of automatic Traffic lights
4. Introduction of intelligent traffic lights systems and
5. Introduction of Regular cycle of maintenance
Panic Days
The police and general public become more and more worried about pedestrians and increasing accidents at this stage. Apart from the above the other concerns would be:
1. Increasing commuter time of professionals and government officials becomes intolerable.
2. Ad hoc solutions like flyovers shifting the congestion to other junctions
3. Solutions like signal free smooth flowing traffic between important high densities routes with Road over Road option.
4. Multiple modes of transport
The Days of realization
The dark days of panic have to be followed by the dawn of realization that providing extra transport infrastructure solutions are not endurable in a fast growing economy. Innovations are the need of the hour. They are in the realm of
1. policies
2. land use planning strategies
3. Road Network Design
4. Road Building technology
5. Vernacular land Development
6. Land Ecology
The Current Scenario
Realization of enormity of the cities transport problems
A thought for Pedestrians(8)
The writer, Praveen Sood, an additional commissioner of police (traffic), in Bangalore, India, writes in the Times of India a reputed newspaper of the country:
In 2008 of the 810 fatalities, 60% were pedestrians. Their right of way has been snatched by distorted policies, skewed implementation, prejudiced mindsets and apathy. Popular statements like ‘signal-free drive’ without creating facilities for pedestrians are an antithesis to the right to life. Today, it's impossible for anybody -- forget senior citizens and children -- to cross a road without endangering his or her life due to absence of infrastructure. But all of us First, motorist-centric policies should be put aside and instead, pedestrian-oriented policies adopted.
The Chaotic prevailing road network management reality
After Independence and especially after globalization the growth in the city of Bangalore is so fast that the standard urban development concepts being followed would no longer be satisfactory. In Bangalore as well as in many other cities in India enough pedestrian infrastructures are not provided because of shortage in funds and in adequate or absence of suitable policies. The variety of chaos can be summarized with the following:
1. The list of designated one ways including their one way direction are constantly changing
2. The status of roads gets elevated periodically.
3. The two roads, with opposing traffic are separated by a median. The right turns are restricted.
4. There is no service road
5. No places earmarked for high voltage power and other communication cables.
6. There are over head domestic and commercial power cables running on electric poles.
7. The right to run TV cables on electric poles is sold to the operators causing unacceptable usage of these street light poles.
8. The bare aluminum power cables which are run on the street light poles are ugly, hazardous and badly maintained.
The traffic lights are placed as shown at suitable over head locations at the junction square. Without any police manning these traffic lights, motorists are prone to jump the signals.
Figure - 1 Two Dual ways crossing with Traffic Lights
These arterial roads attract commercial ventures on both sides of them. Parking, which is at best only an after thought, becomes a problem resulting in the hasty no parking signs.
The Pedestrians moving in and out of the commercial establishments on to the foot paths as illustrated in Figure 1. Above, results in heavy pedestrian interference on the roads. The foot paths alongside of the roads are used to grow huge trees, obstructing the pedestrian movement. They are invariably uneven and hazardous to walk on. Thus the walk ability of these foot paths is poor, which compels the pedestrians to step on to the road. Thus the main arterial roads as conceived to day, inherently not conducive to smooth vehicular traffic, by such faulty design. The principle of convenience resulting in the above faulty design therefore needs to be addressed, scientifically.
The present dual way road which is separated by a central safety median, the right turn due to the opposing road traffic is restricted. With the proposed innovation of “Discarding the median” it is possible to have unrestricted left and right free turns at any required designated locations.
The Discarded Median Innovation
With the arguments put forth in the preceding paragraphs, we now introduce the following innovation:
1. Whenever there is a requirement for a new road in the outskirts of a city, instead of building one dual way road, separated by a median, build new or modify existing two roads separated by a wide enough usable land as a pair of two one ways. These roads need to be barricaded, so that free NMVT access to roads is denied, except at the Bus Stations.
2. In the case of an existing arterial road being selected, the criterion should be based upon serving the needs of the entire city, optimally.
The idea behind this innovation is to save the obtrusive wastage of the median! A road should allow free access to both sides of its penetration in to the land, as shown in Figure-2. While a dual way road allows free left turns, the right turns do pose the problem. So why not have usable land at the right too! Hence it is wise to replace "the wasted obtrusive median" with a usable land. This usable land is a potential prime commercial land, served on both sides by arterial roads. We call this innovation as the "discarded median innovation" Further proper community planning either "Urban" and or "Rural" goes hand in hand with this dual road penetration. Commercial activities like food courts are first to arrive at the land sandwiched between the pair of two one way arterial roads.
The concept is illustrated in Figure 2. In the current practice as shown, there is a single road bifurcated by a meridian. The traffic on either side of this meridian is opposing to each other. The main bottleneck in this arrangement is the Right turn, which requires two slots for allowing the right turn for each direction of traffic, with a traffic lights arrangement. The proposed design, replacing the meridian with usable land is free flowing with no need of the traffic signal. The reason for barricading the road on both sides is the segregation of pedestrians.
Figure 2 The Discarded Meridian Innovation
The Modular Road Network Design Concept
In this article a modular design concept, for a conscious segregation of the vehicular Traffic from the pedestrians, is developed. This modular urban (or rural) road network design concept, allows us to deliberately segregate vehicular traffic from the pedestrians.
The concept
The road network in any existing city like Bangalore for example can be visualized as an assembly of only two basic modules.
1. A Road module (RM)
2. A Road Junction Module (RJM) with crossing of two Roads at right angles
It can be shown that with a combination of the above two basic modules, it is possible to build the entire road network of a city.
The Road Module
The road module consists of the following elements: 1. Left lane 2. Center lane 3. Right Lane 4. Two Service roads and 5. Two Barricaded Green belts. Free turning access to both left and right directions is possible due to the fact that useable land is made available on both the sides, due to the current design innovation. The commercial area is to the
Figure - 3 The Road Module
Right, where as the rural or urban communities on the left. Since the green belt is barricaded, the entry in to the road is only at allowed design points and hence is under control. The module is unaffected by the type of community either rural or urban the road is penetrating. The Land to the right of this module is a potentially valuable prime property, due the fact that a complimentary road with opposing traffic will be simultaneously built by design
The Barricaded Green Belt Module
The green belt is to be barricaded on either side so that pedestrian’s access to the belt is denied. In tern the barricaded green belt bars the pedestrian access to the roads too. Note that Pedestrians access to the road network is thus deliberately avoided through out the network.
The Service Road Module
The service road is where various conduits with easy access panels, should be placed underneath the service road surface. Service road can also serve as distress zone for vehicles in distress.
Introduction
The Lane Transit Zone Bill Board
Vehicles that need to go left, straight, or right at a junction need to be on their desired respective lanes while arriving at the junction. They should start aligning in the transit zone preceding the actual road crossing. This transit zone should be easily identifiable by over head display boards placed appropriate locations at the start of the zone. This is essential as a reminder to the commuters, to align in time.
Figure - 6 The Over head Transit Zone Bill Board
Two Road Junction Modules
Here we consider two types of junction modules. The reason for this is that these are the two basic modules which are least complicated and are elegant. The schematic with either of the road junction modules results in a signal free continuous flow traffic.
RJM(1x1)
Two one way roads crossing each other at right angles. These modules are placed at each junction of the entire road network. While the south bond traffic, in this example, crossing the junction goes below the north bound, it is able to take a free level left turn; to join the east bound traffic. Similarly the east bound traffic is able to take level turn to join the south bound traffic.
Figure - 7 The Road Junction Module (1x1)
Road Junction Module -(1x2)
As is evident from the two sketches a single underpass is used to grade separate the crossing traffic. Separate Pedestrian crossings are provided for each road at both road segments. The pedestrian crossing for the road going through the under pass has to be provided at the ends of the ramp. Thus the complete set consists of a total of eight entries cum exit booths, four on either side of one road. There are easy ramps provided for Disabled people chairs as well as for the Hawker carts, with central steps so that people can climb or descend with the carts or wheel chairs.
Figure - 8 The Road Junction Module (1x2)
Note: The two way traffic road shown above in the West East direction is the old Median Separated traffic which however is not advocated for Major arterial roads. It can be at best be adopted at Minor Arterial roads if so desired, intermittently.
Communities
A community is defined as the one served by arterial roads (one way) at all four sides of it. A typical community is encircled by one way roads. Entry and exit points are provided at central location on each side of a community. All the roads inside a community are dual way roads. Communities in turn are of several kinds.
1. Business
2. Commercial
3. Urban Residential
4. Rural
5. Heritage
6. NO Motor Vehicles Market Spaces
7. Amusement parks
8. Ecological Farms
9. and more
We exclude the Educational institutions specifically from residential category, in this discussion.
Business community
Figure - 9 The Mall
The Malls are places which attract big daily crowds who throng the big screens, shopping centers and food courts. They have multiple level parking spaces. As such the land served by four one way roads on all the sides is ideal locate them.
Commercial community
Commercial communities are in the in between two Malls. Thus there are four commercial communities encircling one residential community. Here one has to observe that the traffic flow pattern around the community is different. The traffic is not going round the community. However it is possible to go round the community including the two corner business communities.
Figure - 10 The Commercial Area
Residential community
A residential community is the neighbor hood where people reside and do not indulge in commercial activities, requiring a group of working people who do not reside at the community. This kind of activity may affect the tranquility of the neighborhood. The strategy is to provide enough space for commercial activities around each residential community insulated from it served by major arterial roads. Thus the innovation is to keep the commercial belt sandwiched between two one way arterial roads. Residential community needs to have land for RWA, club and recreation etc apart from that required for the residential buildings. Malls and business centers should surround the Residential communities as a policy to facilitate separation of the two. The residential and commercial land should have sufficient distinct foot path area as shown in the diagram as yellow space. Pedestrians can access the Mall, commercial and residential areas only by road crossing through the under passes provided. It can be seen that they do not have any direct access to the arterial roads at all. These arterial roads are as can be recalled are barricaded and restrict any entry of pedestrians, as such.
Figure - 11 The Communities
The Green Area
The green area in a residential Community is placed centrally and provides the land for Vegetation, RWA, Club and recreation facilities for the community
Figure - 12 The Green Area inside a Community
Conclusions
This article proposes a network of arterial Roads made exclusive for transit, by barricading both sides of them. The pedestrian’s access to these roads is restricted to bus stand areas only for transit to other locations. This new concept is valid to both urban and rural land development. The innovation of using these barricaded roads in pairs of dual one way roads separated by useable land in between provides for free left as well as right turns, which provides better accessibility.
The proposed network of roads encourages natural zoning of Residential, Commercial and Business land use by suitable land area ratios maintained among them. The concept is applicable in both Urban and Rural context.
Pedestrians are discouraged to mix in to arterial roads as they are made devoid of any buildings on both sides of the road. Foot paths are provided inside the Commercial, Business and residential areas, as the arterial roads are barricaded. Pedestrian access to shopping and business areas is facilitated by provision of pedestrian under passes at all arterial junctions.
Non arterial Roads are entirely interior to all usable zones like Commercial, Business and Residential communities. These are inter connected only at center locations of each of four sides of the quadrilateral boundary of any typical zone.
Saturday, March 28, 2009
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