AIIMS Flyover-Appraisal of Landscape

AIIMS FLYOVER A CRITICAL APPRAISAL OF LANDSCAPE ELEMENTS

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SCHOOL OF PLANNING AND ARCHITECTURE

AIIMS FLYOVER

INTRODUCTION

Delhi, an ancient city with history dating back to the time of mythological Pandavas has

been a major destination for travellers from India as well as from outside. The planning of

the city has changed with the change of rulers like the Mughals, the British and the present

system. The road system of the city is ring-radial and bulk of the traffic is road-based only as

till recently no other mode of transport was available. The Ring Railway, started in the year

1954, did not serve the desired purpose on account of the development of the city has

taken place. The unprecedented increase in the number of vehicles has choked the road

system.

Most of the capital cities in developed countries have multi-modal transportation systems. The metro rail project in Delhi, though started recently, may take-off fully only after another five years as a result of which the traffic congestion on the roads in the command areas of the metro rail may be reduced. But, it is important that the problem be addressed in the transition period. As per the master plan of Delhi dating back to 1962, three Ring Roads were planned, namely, the inner Ring Road, the Ring Road and the outer Ring Road. The inner Ring Road however, did not become a complete entity and has remained largely dysfunctional till date. The other two Rings, i.e., the Ring Road and the Outer Ring Road acted as the main transport arteries. Till the late seventies, the Ring Road was the major traffic artery as the population around the Outer Ring Road was sparse. However, both these roads carry large volumes of traffic presently and urgent steps were needed to ensure faster and smooth flow of traffic. As per the study commissioned between 1988 & 1991 by the then Delhi Administration. For decongesting Ring Road, construction of three level grade separator at the intersection of Aurobindo Marg and Ring Road near AIIMS was recommended apart from making similar suggestions for other important intersections of Ring Road with the other roads. FLYOVER DESIGN The flyover was a cloverleaf design flyover. Since the configuration of the flyover had to be accommodated in fully built up urban environment, it was necessary to fit the configuration in minimum possible space so that least number of structures and services were disturbed. Due to limitation of space, the loops had to be provided with tight radii and the permissible speed of the vehicles on the loops had to be restricted to 30 km per hour. The radius of left turning loop from INA to Dhaula Kuan varies from 70 metres near the transition curve, and thereafter reduces to 35.5 metres. The radius of the left turning loop from Green Park to South Extn varies from 122.3 metres near the transition curve to a radius of 35 metres. The radius of the U-turn for the traffic coming from the Dhaula Kuan side and entering into Safdarjung Hospital had to be restricted to 9.9 metres. The down


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ramps from the two flyovers have been given a slope of 1 in 30, except for the climbing ramp from Green Park which has a slope of one in 20 just before the loop meets the skew flyover. The clearance below the flyover has been kept as 5 metres in order to enable the fire tenders to move freely. The width of the roads varies from 7 metres to 11 metres. The width of centeral verge has been kept as 1.2 metres on the underpass along Aurobindo Marg. For the roads going on both the flyovers, double faced crash barrier having a width of 0.65 metre at its base acts as the central verge. Footpaths have been provided at ground level along all the four slip roads for pedestrian movement.

Figure 1 Design as approved by the infrastructure committee

The width of the roads varies from 7 metres to 11 metres. The width of centeral verge has been kept as 1.2 metres on the underpass along Aurobindo Marg. For the roads going on both the flyovers, double faced crash barrier having a width of 0.65 metre at its base acts as the central verge. Footpaths have been provided at ground level along all the four slip roads for pedestrian movement.

In order to make the flyover less obtrusive, it was decided to restrict the total rise of the flyover. The Aurobindo Marg was, therefore, depressed by 2.5 metres and the Ring Road was raised by 4.5 metres. Plate 3 shows a photograph of the model of the flyover scheme.

AIIMS

DILLI HAAT

MAHATMA GANDHI MARG

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Figure 2 Photograph of the model of the flyover scheme

STRUCTRAL ARRANGEMENT The interchange consists of two flyovers across Ring Road, one being curved in plan and the other skewed figure 3 shows the locations of these flyovers along with retaining walls. Both the flyovers have a solid slab super structure having a maximum thickness of 1.7 m at the piers reducing to 1.3 m in the centre of the span. The super structure is continuous over the supports to reduce the number of joints so as to ensure a better riding quality. The super structure is supported over solid piers, which are aesthetically pleasing. GAD of the curved and skew flyover is shown in figure no.4 and 5.

Figure 3 Location of retaining wall with curved and skew flyover and under pass

EAST KIDWAI NAGAR AIIMS HOSPITAL

WEST KIDWAI NAGAR SAFDARJUNG HOSPITAL


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Figure 4 GAD of curved flyover


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Figure 5 Gad of skew flyover


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LANDSCAPING AT AIIMS FLYOVER

AIIMS CLOVERLEAF AND ITS APPENDAGES

Figure 6 beforeAIIMS clover leaf flyover was built it was possible to take the shortest direct route to Delhi haat but………..

Figure 7 ……..after AIIMS clover leaf flyover has been built walking distance has increased manifold

Walkways around hospital do not address specific needs of ailing visitors: the pedestrian

ways around the ALL INDIA INSTITUTE OF MEDICAL SCIENCES that number to a large

number of ailing people visiting the hospital presents a dichotomous situation.


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The cloverleaf flyover that has been created in its vicinity of aiims has disrupted at-grade

continuity in its proximity, and increased distances for the ailing visitors approaching the

hospital from the side of the ring road.

DESIGN CONCEPT

Delhi’s first site specific, stainless steel contemporary sculpture, ‘sprouts’, a project

designed by jindal stainless limited. It was conceptualised in 2007 by sculptor Vibhor Sognai,

sprouts has two clusters of giant metallic sprouts -- one has eight, with the tallest one 35

feet tall, while the other cluster has over 400 smaller sprouts, 3 - 5 feet high. Made of rust-

free, 304 and 316 grade stainless steel, the sculpture is organic to its location.

The globes of the sprout have been designed in such a way that the top half reflects the sky

and lower half the green on the ground.

The ground itself has been re-landscaped by Ravi Punde and special lighting has been done

by Caurtney Mark from the United Kingdom.

Figure 8 Sketch of AIIMS flyover

Figure 9 AIIMS flyover after landscaping


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The project, titled `Sprout', aims to symbolise progress made by the country since

Independence, and its march forward. Driving past the roundabout at present, one sees

large mounds of mud in varying sizes dotting the islands. These are part of landscaping

activities being carried out under the supervision of landscape architect Ravi Punde. "We

will have several mounds that will give the islands a rhythm, with Kadam trees around the

perimeter giving a forest feel," Punde said. "We chose the sacred Kadam tree since it is

medicinal and gives a stately feel of a forest." The most expensive part of the project is

installing eight special LED lights imported from a UK-based manufacturer, costing Rs 1.75

lakh each. These lights can give out different colours and will be used to highlight sculptures

on the islands.

DRAINAGE AND GROUND WATER RECHARGING

The flyover is spread in an area of more than 4 hectares with a number of loops and green

spaces in between. The storm water drainage has been designed to be gravity based, as it is

the most economical and foolproof system. Trunk mains have been laid along the periphery

of the flyover scheme, i.e., along the four outer slip roads namely (i) road from INA to South

Extn. (ii) South Extn. to Green Park (iii) Green Park to Dhaula Kuan and (iv) Dhaula Kuan to

INA.

The main peripheral trunk mains collect the discharge and dispose the storm water off to

the nearby Kushak Nallah. In order to bring the storm water to those peripheral mains, a net

work of open drains, covered rectangular drains and pipe drains has been laid. Drains have

also been provided along the deck slab of the curved and skew flyover to collect the surface

water and down take pipes have been provided on the abutment to bring this water down

to the main drainage system. The underpass is the most critical from drainage point of view

as it has been depressed by approximately 2.5 m. For the underpass also, the storm water

will be disposed off first by gravity through 0.5 m wide rectangular drains with removable

covers to facilitate cleaning. These drains run parallel to the underpass on both sides.

Recharging bores are being provided to collect the water from these drains so that he storm

water is used for charging of the ground water as recommended by the Central Ground

Water Board. As a further foolproof arrangement, the storm water shall be pumped from

these shafts in case the recharging bores are not capable of transferring the water to the

ground water table. Separate grids for pumping main have been laid. In order to drain the

pedestrian subways, pumping arrangement has been provided.

Central Ground Water Board in NCT, Delhi, has provided technical designs for 33

flyovers. Intersection of Ring road and Aurobindo marg at AIIMS crossing is one of the most

important flyovers in NCT, Delhi. Runoff from this green flyover is utilized for recharging to

the aquifers. The total runoff available in this flyover is about 35000 cu.m., which is

recharged to the aquifers through 10 recharge shafts constructed at different locations

of the flyover. The shafts are associated with recharge tubewells of depth 25 m to recharge

the ground water aquifers.


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Figure 10Location of recharge structures at AIIMS flyover

Figure 11 Artificial Recharge structure at AIIMS flyover

LIGHTING

Efficient lighting of the interchange area is a must for safe movement of traffic and

pedestrians. The design tends to demand more attention due to complicated configuration

where individual carriageways must have light of adequate illumination level and uniformity

ratio. This has been provided by a judicious mix of 13 nos. of 30 m high light masts with

conventional street lights along slip roads in two quadrants. The landscaping has been


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planned in such a way that no shadow reaches the carriageways even when the plants grow

up. Special care has been taken in the areas below the flyovers. These high masts and the

pedestrian subways are partially lit up through a emergency generator in care of failure of

electricity. A dedicated sub-station building has been provided for these services. The area

below the deck slab is lit with lights fixed on top of the piers.

Figure 12 Lighting at AIIMS flyover

ROAD SIGNAGE

The interchange caters to 13 directional movements over two flyovers, one underpass and a

set of loops running at different levels. In order to ensure effective guidance to the traffic

using the interchange, a scheme of overhead and curb mounted informative road signs was

devised and the road signs were fixed in a planned manner. The foundations of the

overhead road sign structures were integrated with the main flyover structure or the

retaining walls depending on the location of the sign. An innovative architectural design for

the road signs was specially designed which consisted of a 350 mm dia M.S. pipes for

vertical posts and the same pipe was used in the horizontal direction instead of the usual

truss being provided elsewhere, Plate 27. The signboards were hung from the top pipe and

the entire structure looks very sleek and un-obstructing. The signboards have been provided

with high intensity retro reflective sheeting pasted over 2 mm thick aluminium sheet.


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Figure 13 Road Signage at AIIMS flyover

ENVIRONMENTAL CONSIDERATION

A number of trees were affected by the interchange configuration. A summary of all the

affected trees was prepared indicating the species, height and girth of each tree. For this the

position of each tree was marked on a plan and was assigned a unique number. The trees

were got inspected by the Forest department and as per their recommendations, a total of

147 trees (113 in phase I and 34 in phase II) were transplanted and 156 trees (150 in phase I

and 6 in phase II) were cut in order to accommodate the flyover configuration, figure 12. For

every tree that was cut, 10 trees were planted at other locations as compensatory

plantation. Kadam trees were planted at the site.

Figure 14 Kadam tress planted along the flyover


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OBSERVATIONS FROM PHOTOGRAPHS AND SURVEY

Combination of small and large earth mounds creates a dominant landform that:

Dominates the vision at high speed.

Enframes the large and complex road structure

Use of vegetation (predominantly ground cover and small shurbs) along with steel structure

contemporatry scluptures conceptualised by sculptor vibhor songai.


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Though the flyover has created continous flow of traffic and served the connection; there is

no easy pedestrian connectivity.

Space just below the flyocver are unutilized that can act as an interchange space for

pedestrians.


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There are two clustur sprouts – one has 8 no. With the tallest one 35’ tall while the other

cluster has no. Of small sprouts 3-5’ tall.

The globes of the sprouts have been designed in such a way that the top half reflects the sly

and the lower half the green on the ground.

The median is totally hardscape and there is no plantation.


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Loose pedestrian links, badly maintained and absence of cross walk facilities (at grade,

subway and foot over bridge), has high modal conflict. The mounds helped in water

recharge.

The zones outside the loop are in a state of neglect which can be improved with distinct and

non – distracting treatment which should at the same time be visually significant over a

short time frame.


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INFERENCES

The AIIMS cloverleaf flyover has an island with several mounds that gives island a

rhythm and kadam trees around the perimeter to give a forest feel.

The mounds are built in coherence with the contour which facilitates ground water

recharge and drainage.

There are water recharge structures installed by CGWB to recharge ground water.

The mounds and steel sprouts dominates the vision at speed and enframes the large

and complex road structure.


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CASE STUDY

PARC NUS DE LA TRINITAT, BRACELONA

Parc nus de la trinitat (1993) is located in one of the most important road networks in

bracelona.

Parc nus de la trinitat, bracelona is done by joan roig and enric batlle is in north east

bracelona, inside a circular motorway junction. The scale of the six hectare park is defined

by a framework of trees forming a spatially effective filter between the motorways and the

park. A circular gallery divides the park into an inner and an outer area.

The park location is definitely difficult, with multiple

lanes of converging traffic. The use of buffering bands of

vegetation, water and beaming creates separation from

the immediate context, to the point where you can’t see

any of the traffic ways from the park interior.

It includes a water channel, two tennis court, urban farm

gardens, a volleyball court, a basketball court, a mini

football pitch and picnic areas.

The layout no doubt echoes the presence of the ring

roads, nevertheless the roundabout and its traffic are

visually and aurally screened out:

Through grade changes

Landform construction and strategic planning

Figure 15 Landscaping of Parc Nus De LA Trinitat


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References

Construction of grade separators at the intersection of ring road and aurobindo marg, new Delhi – a success story, S.P. Banwait, S.S. Mondal, Rajeev Singhal Mr. Manoj Mathur; M/s Mathur & Kapre, Consultant AIIMS flyover design Mr. Ravi Punde; Design Cell, Landscape Architect, AIIMS flyover Annexure VI, Plantation Scheme, PWD, Horticulture Department

Documents

AIIMS Flyover-Appraisal of Landscape