& Subterranean

Canalization (Cloaca Maxima “The Great Sewer”,Ancient Rome)

More than 2,500 years ago, Etruscan kings built the Cloaca Maxima, a system of ancient tunnels beneath Rome, to direct rainfall and drain a marsh so they could regain land. It is a significant example of major public works, infrastructure projects, and a historical use of the arch in Rome. Despite its shortcomings, it was a step up from using the streets as sewage systems and latrines, which allowed Rome to grow and prosper.

With manual labour, hand tools, and a great deal of human sacrifice, the Cloaca Maxima was constructed. The workers' lives were miserable, and many of them chose to suicide to escape their difficult, demanding, and hazardous jobs The system was also employed to dispose of human and animal waste, but the ancient engineers lacked the knowledge necessary to stop sewer gas from escaping, endangering the Roman populace by causing hazardous evaporation However, the Cloaca Maxima endured for more than 2,600 years, serving its purpose and helping to define and encircle Rome

Underground Arched Passageways for Pedestrians and Vehicles

During the Cloaca Maxima era, the ancient Romans invented the concept of the Cryptoporticus, which were vaulted tunnels used for both residential and commercial purposes Often underground, these serene, shaded lanes lined the terraces or platforms that supported tall buildings They occasionally served as ambulatories and stood next to streets The Cryptoporticus tunnels were lit by tiny windows placed in the vault along one side Many of these tunnels are still in use as thoroughfares for traffic or pedestrians today.

The Murray Hill Tunnel (NY), the World’s Second Subway Tunnel

The third was the Metropolitan Railway in London, which began construction in 1853 and was completed in 1863.construction of a subterranean railway. Due to uncontrollable traffic congestion, this subterranean, a 2-1/4 mile short line railway extension of the Great Western Railway, had to be built immediately. some of the for full grade separation, the route needed to be built as both an open cut and "cut and cover" tunnel It was a main line railway operation rather than a specific fast transit route.

The Metropolitan Railway line in London is the first line of the London Underground. The railway extension was built using the "cut and cover" and "open cut" methods to provide grade separation for the Great Western Railway's extra passenger and freight access to the Thames River via downtown London The Metropolitan Railway line's design, which utilised advancements in structural engineering theory, was influenced by the Atlantic Avenue tunnel in Brooklyn and Manhattan

The British engineers employed abutment walls with elliptical forms to maximise the structure's underlying shape-strength and use fewer materials while building. The Metropolitan Railway line, which was established to enable mixed-use (passenger and freight) transit, services.

Epilogue: Greathead Shield & the Deep Tubes

The "deep tubes" built for the London subterranean in 1886 using the Greathead Shield were a significant development in subterranean construction. The shield was a cylinder with steel blades that hydraulic rams drove into the earth to facilitate the excavation of a railway tunnel without using the "cut and cover" method The City & South London Railway, which used this technology, was the first deep-level subterranean passenger railway in the world as well as the first urban electric traction railway in England This opened the way for the construction of urban rail networks in cities all over the world in the late 19th and early 20th century.

Tower Subway - Part of the Secret London series (historic-uk.com)

1.2 HISTORYOFPEDESTRIAN SUBWAYIN INDIA

the concept of subway was became popular during late 19 century . from london it spreads all over the world to increase the safety and covinience of the pedestrians to cross busy roads and vehicular congestion . the concept of pedestrian subways in india can be traced back to early 1900s Cities with growing population with increase in traffic iin roads was causing lot of traffic congestion which causes lot of pedestrian problems in order to address this issue brithish administration started to building pedestrian subways to provide safe pedestrian envirorment.

First pedestrian was contructed 1930 during british colonial era in busy crossroads of crawford market and chatrapathi shivaji terminus trian station, mumbai at the same time in 1932 pedestrian subway was built in chennai near the intersectiojn of anna salai and mount road .the concept of subways swiftly caught ton in other in Indian citeis .

At the intersection of Chowringhee Road and Hare Street, Kolkata built its first pedestrian subway in 1934, following Mumbai's lead Many additional pedestrian subways, some of which were art deco-inspired, were constructed in Kolkata during the next few decades.

Time Ofpedestrian Subwayin India

1.3 Subway designguidelines

Hump subways:

Both the car lane users and the pedestrian (including cycists wherever segregated facility is provided) need to have a change in level. The surface of the road is raised (+1.5 m) using a ramp of 1:30 and the pedestrian paths (cycle tracks, wherever provided) are lowered using ramps of slope1:20 with landing at appropriate intervals to equally achieve a clear minimum height of 2.75 m (-1.5 m).

The advantage of such subways is that the walking length of a pedestrian is not increased to that extent that discourages her/him from using it. Fig. 32 shows a typical sections of subway

Full subways: Pedestrian paths are lowered to a depth where a clear height02 75 m minimum can be achieved using 1:20 slope ramps with appropriate landings. The car lanes encounter no level change and maintain the same level Small shop may be included in the planning of subway which may provide a sense of safety to the pedestrian traffic during night time This will also help maintain the subway

Even cost of construction and maintenance of subway may be recovered by allowing shops to operate in the subways. Subway with 40 m length should be provided with forced ventilation facies in busy areas. While planning and designing the subway, an attempt should be made to ensure natural lighting and ventilation as much as possible.

Subwayand foot over bridges(FOB)

In general, escalators are not thought to be a suitable solution for universal mobility. Except in the case of a subway, approaches to footbridges and subways should include ramps, elevators, inclinators, and steps. The widths should be as wide as they may be. According to section 6.8, footbridge ramps with a slope of 5% (1 in 20) and suitable resting areas/landings are preferred.

In the underground, a handrail should be installed between 760 and 900 millimeters above the ground. To help those who are visually impaired, 300 mm before and after, or at the top and bottom of the flight of steps, should be supplied with tactile paving/ties and a color contrast, and these areas should be properly illuminated.

Ramp/fit is mandatory and steps/escalators can be provided. Lift should be provided on both the entrances/exits and should have minimum intimal dimensions of 1500 mm x 1500 mm More natural light forth subways should be provided. Greater safety can be achieved by having hawker space sin some subways and/or video surveillance camera Minimum width of the FOB should be1800 mm.

The ideal solution would be to offer both steps and ramps. Some people with disabilities (such as those who use crutches) find it simpler to utilise steps than a ramp. If neither can fit in the exterior environment, a ramp shouldbe provided. The path shouldn'tbe difficult to follow or lead people in the wrong direction.

1.4 PLAN SUBWAYAND SECTIONAS PER GUILDLINES

1.4 Ramps and Steps

The ideal solution would be to offer both steps and ramps. Some people with disabilities (such as those who use crutches) find it simpler to utilise steps than a ramp If neither can fit in the exterior environment, a ramp should be provided. The path shouldn't be difficult to follow or lead people in the wrong direction

A ramp should be accompanied by a fight of easy-going steps. Slope of ramp is to be a maximum of 1:12 Refer Table 6 for ramp gradients for long lengths which will facilate water to drain away from the ramp surface and from landings.

Grill type gullies can be provided across the width of the ramp surface to ensure good drainage. Sip-resistant smooth surfaces 'can be used such as ribbed or brushed concrete textured stone or macadam. Landings at every 750 mm of vertical rise should be provided and minimum width of the ramp will be 1200 mm.

Handrails are to be on both sides at two levels 760 mm and 900 mm; both ends are to be rounded and grouted and to be extended to 300 mm beyond top and bottom of ramp. Surfaces (ramp + landing) should be sip resistant. Tactile warning tile 300 mm will be provided before and end of ramp to indicate change in gradient. On long ramps, one can provide passing bays, 1800 mm x 1800 mm every 20 m.

Landings should be at least 1500mm x 1500 mm Where a door or gate opens onto a landing, the length of the landing should be at least 1300 mm clear of the door swing. Edge protection 100 mm high is required at the sides of ramps and landings to prevent persons falling through A tuming circle of 1800 mm diameter will be provided at the top and bottom of a ramps.

1.5 Pedestrian facilities principles

Safety, security, continuity, comfort and livability are the key five principles to consider in the planning and design of pedestrian infrastructure for a safe and enjoyable walking experience These principles make walking more attractive over personal motor vehicle use especially for short trips

Safety – Pedestrians should be protected from motorized vehicles to prevent injuries and fatalities due to crashes They should be able to walk and cross safely irrespective of age, gender and disabilities.

Security – Pedestriansshould be secured from crimes while walking.All pedestrians including women, children and elderly should feel secure while using the facilities.

Continuity – Pedestrians should be provided with continuous walking environment without any obstructions.All pedestriansincluding persons on wheelchair, visually impaired persons, caregivers with prams and elderly should be able to move seamlessly.

Comfort – Pedestrians should be provided with well-shaded, well-drained, spacious and clean walking environment They should feel comfortable while walking, waiting at the busstop and seating.

1.6 DesignParametersforAccessibility Accessibility of Subways

All subways and FOBs should have elevators in addition to stairs. Elevators are essential at all grade-separated pedestrian crossingsfor mobility of disabled on wheel chair.

• Escalators may be provided along with stairs to increase comfort, but it cannot be a replacement to elevators, as escalators cannot safely accommodate pedestrians on wheel chair.

• Elevators should have enough space to accommodate at least one wheel chair and a pedestrian to stand.

• Opening to subways and FOBs should have sufficient width at least to allow two people to comfortably cross each other

Safety of Pedestrian Facility Safety of Footpath

Footpath should be well lit with direct lightingon footpath

• Footpath should have an even surface free from obstacles that could create any safety concern for elderly people.

• When footpaths (or ramps) have a gradient unsafe for elderly people to walk, then handrails shouldbe providedat such locations.

• Tactile pavement should be provided at all locations on a pedestrian facility where there is a potential safety concern for visually impaired pedestrians (such as just before a ramp that leads to pedestriancrossing, around an obstruction,before the stairs to a subway access).

• Access to footpaths and medians should be provided to only pedestrians Railings and bollards should be used to restrict access for motorists.

Safety of Pedestrian Subways and FOBs

• Grade separated crossing (subways, FOBs) should be designed in a way that is safe for vulnerable group of pedestrians such as women, children and others who may be targeted by miscreants

• Subways and FOBs should be well lit all throughout the day for safety of women and other pedestrians · FOBs should have protective railing bearing in mind the safety of children

• However FOBs should not be fully enclosed in a manner that the pedestrians on the FOBs are not visible from the road (by opaque design, advertising or for other reasons), as enclosed FOBs can be claustrophobic for some potential users and may also encourage miscreant activities. Hawking space should be assigned and permitted in the grade separated crossing to improve the safety for pedestrians.

• Automated surveillance cameras can be utilized for stricter enforcement against miscreant activities and misuse of grade separated crossing