In the recent past, many pedestrian underpasses have been built at various locations. However, the utility of these for pedestrian crossings has been minimal & one hardly finds pedestrians using them, unless forced to with barricades (eg. Pedestrian subway at City Railway Station, & at KBS).
This raises questions as to why they are ignored by pedestrians. One obvious reason is that everyone prefers to cross a street just about anywhere based on individual needs & requirements. The other, not so obvious reason is the discomfort in using them, especially for old people, small children, disabled people & pregnant women. The ordeal of descending about 8-9ft & climbing up again is perhaps a strain even for ordinary people when coupled with walking, sometimes long distances. Overhead walkways are even more uncomfortable for people as they have to climb even higher & then descend back to street level (about 12-15 ft or more, in some cases).
BBMP may claim to have addressed the needs of pedestrians by building these, but in the larger interests of users, a solution is necessary to ensure that these do not remain mere showpieces.
What if we make the subways as shown in the sketch above ? Position the subway midway below street level so that pedestrians need only descend about 4 feet instead of the usual 8 ft or more. Needless to say, an elevation of the road would also be necessary, stretching over a length of a mere 55 ft, or about 17 mtrs for a gradient of about 10 degrees. This rise in street level will also ensure that pedestrians do not cut across the street over this stretch & will have no option but to use the subway. Sidewalks will need to be maintained at grade, throughout & preferably barricaded for safety of all.
If designs that do not require pedestrians to physically stress themselves are adopted, such as the example above, we might see better utilization of pedestrian subways.
Appreciate your inputs & ideas in this regard.
ಪ್ರತಿಕ್ರಿಯೆಗಳು
Non stressful stairs
this is basically a magic
this is basically a magic box for pedestrians! good idea!
bring srivatsa's attention to this...they are working on a footpath improvement plan to propose to BBMP.
Space Constraints
IDS - Good example for locations where there is ample space, also assists wheel-chairs, prams, & hand carts !
At most locations, we seem to have space constraints. I think the walk distance also increases with this design, is'nt it ?
What is height of Human Being?
1.0 We need a flyover for pedestrains to stay at grade?
2.0 Is this only for wheelchairs without the attendant?
pls enlighten us.
nJ
-nJ-
919462900144
www.nitinjhanwar.biz
Good idea, but cant be used everywhere!!
Naveen,
I would concede that this is a good idea, especially if conveniently sloped ramps are provided to enter the subway.
But, this cannot be the template for every subway we have to construct in the future. I would argue that this augurs well for the kind of ped underpasses that are built on the roads away from junctions (Eg: opposite RBI on NT road).
What we need further is not subways to cross a road, but ones to cross a junction. That could well mean a network of such ped underpasses. While at Basaveshwara circle, there are two 'magic' ped underpasses, what we actually need is a loop which forms the subway,and entrance/exit to both sides of each road at the junction. Only then can we effectively provide safe access to ALL pedestrians at the junctions.
-Srivatsava V
-Srivatsava V
Forgot the metro!!
While I talked about subways to 'safely' cross the junctions and not just roads, the introduction of metro will provide an additional necessity.
For attracting ridership onto metro, we need more (number of) larger/longer and wider subways as entry points to the Metro station. Additionally, the subways and stations should be designed such that they are merged into one entity. i.e. the pedestrians should be able to use the subways without 'entering' the metro stations!!
Additionally, for both the Metro and pure-pedestrian 'junction subways', we need to interconnect two or more of those subways underground, so that users can enter the subway at one junction and walk underground for the next 1-2 junctions, and get out of the subway network at another junction!!
-Srivatsava V
-Srivatsava V
Calculations... for an inclined road?
Naveen,
You are right. Ramps tend to lot more space(longer) than stairs. But, for this part submerged design, ramps may be fine, since the depth is just four feet.
Some of the present ped underpasses are not completely submerged in the ground. They may raise about 1-2ft over the ground. We need to solicit feedback from various road users to understand its effects. We may have to talk to traffic police to assess the impact on traffic flow and average speeds. Only then can we consider raising the 'magic box' four feet over the ground.
Also, your calculations are for a levelled road. Can I assume that the total 55ft width holds good even for inclined roads. This design could make the calculations awry. See the impact this has? Can you assess the lengths affected on the road (top right '?' symbol) and the ramp length for the ped (bottom left '?' symbol)
(Click on the image to view to more clearly, on Flickr)
-Srivatsava V
-Srivatsava V
Ped Subways - This Sketch May Help
This sketch may help in understanding the design better :
The throughput with an 8' x 8' subway will be small & these will be suitable only for street crossings (eg. those across Bellary road, across Nrupathunga road, across Old & New Airport roads, etc.).
For larger throughputs, such as those at 4-way or 5-way junctions or at Metro stations, larger widths will be required (say 12' or larger) to cater to higher volumes of pedestrians.
However, the height can be retained same (viz.8') in all cases & the subway need only be 'buried' about 4' below the ground, instead of 8' or more. This will make it more convenient & reduce stress for users, thereby improving utilization.
For inclined roads, similar designs can be adopted, but the rise of the road on one side will be longer than on the other side. The overall length over which the road will have to be interrupted for the rise & fall may however, remain approximately the same.
Proper earth compacting & street side retainer "walls" will be necessary, similar to large flyovers, but since the length & height are small, this should not be difficult & will be a small expense.
subways
ITS HEARTENING TO NOTE THAT WONDERFUL SUGGESTIONS R COMING FROM PRAJA MEMBERS. BBMP SHOULD TAKE NOTE AND IMPLEMENT THEM OR AT LEAST MAKE SINCERE EFFORTS TO IMPLEMENT.
IF U CANT FIND HAPPINESS ENROUTE , YOU WILL NEVER FIND AT THE END
IF U CANT FIND HAPPINESS ENROUTE , YOU WILL NEVER FIND AT THE END
usable vs used
Saw this related report today. Is this because it is not "usable" or it is not being "used" because it is a little far away?
Ped Subway - Correction
IDS - Perhaps both reasons !
Re. The later sketch for design of Ped Subway, the subway is shown 'sunk' by 3 ft below ground, thus, the road has to rise up by 5' (not 4' & 4' as previously mentioned). Thus, the calculations would correspondingly differ, but the point remains valid, viz. make it much easier for the pedestrian & not for motorized vehicles.
You cant have a camels back for vehicles!!
I dont agree, sorry but this is not engineering.
There have been inadequate designs for flyovers which have resulted in fatal accidents.
Vehicles dont prefer raised "speedbreakers"
The best option is to have the peds at grade under a flyover.
nJ
-nJ-
919462900144
www.nitinjhanwar.biz
Priority for Pedestrians, Not Vehicles
NJ - Your comments welcome.
Could you please describe the inadequate designs for flyovers that have resulted in fatal accidents, particularly in relation to this thread which is about designing pedestrian subways for better utilization ?
You state that vehicles do not prefer raised "speedbreakers". These would be similar to small bridges & not speedbreakers - the length of road effected is only about 57' by calculation. Second, it is not an inconvenience to vehicles since they will never have to slow down, but rise up on a small slope & then proceed down on the other side also on a similar slope. Third, even if it causes some inconvenience to vehicles, that is acceptable & preferable to inconveniences to pedestrians.
"The best option is to have the peds at grade under a flyover, at grade"
- this is also unclear - Is your suggestion to have the pedestrian pass at grade with vehicles rising the full height up (about 9', including road surface) & then going down slopes ? If so, the road length effected would be much longer as the rise is higher, necessiating alterations along longer distances.
Camel back engineering
I dont agree, sorry but this is not engineering
I tend to agree with you. It did seem to not go with the flow. The contours of a street go out of whack. Camels back is a good analogy. I am sure there are other less cumbersome ways of not making people have to walk up or down too much. It was called zebra crossing. We have forgotten about it. If we are ready to inconvience vehicles we should make them stop at zebra crossing.
Leave the engineering pls.
Thanks idontspam,
"The best option is to have the peds at grade under a flyover, at grade"
Should be read as "The best option is to have the peds at grade under a flyover in relation to this thread"
and Naveen I rest my case.
nJ
-nJ-
919462900144
www.nitinjhanwar.biz
Nice design Naveen
The current pedestrian underpasses or skywalks are impossible to negotiate for people with disabilities and the elderly.
The ideal is for pedestrians to be at grade, and vehicles going above or below. This would mean zebra crossings, but this need not necessarily mean vehicles stopping at themif they are used in conjunction with coordinated signals.
Where an underpass is unavoidable, Naveen's 4' dip design is a very nice idea, definitely better than the current design of pedestrian underpasses or skywalks.
Two more points that can be included in the design in some way:
1. Ventilation : Very important in longer underpasses. Try going through the City Market underpass - I actually feel suffocated. Also bad from the public health point of view since it will definitely spread air-borne disases.
2. Security : Important in the less populated underpasses. I used to walk through the one on Race Course Rd. (before it broken up to widen the road) in the evening, and it was scary because there used to be nobody in it. High possibility of getting mugged. This alone can cause people to avoid using an underpass in which case its purpose is defeated. I actually used to avoid uysing it after dark.
This is a very tricky problem, and one solution could be to increase the visibility into the underpass from the outside.
IDS, NJ - You Maybe Right, But...
IDS & NJ - You are correct about zebra crossings being the ideal solution as they cause no inconvenience to pedestrians - I would also have preferred those to anything else, but unfortunately, they involve safety hazards & monitoring.
Considering that pedestrian deaths in relation to other road accidents are the highest in the city, I feel that grade separation is called for to provide safer means & this was one option I felt might work, especially after seeing similar designs in China & also in Mumbai.
I would prefer you not ridicule it since others have found it suitable & I also do not see how or why these are being argued as unsuitable when so many similar magic boxes are being put up for vehicle movements involving even higher rises & falls contours on streets. Are pedestrians not deserving of similar considerations ? If at all, the design that I have mentioned reduces the rise & fall & over a smaller distance whilst allowing the pedestrians to descend & ascend fewer steps than those that maintain at-grade streets (like the ones being installed by BBMP).
I request other/s to comment about this.
ok
I would prefer you not ridicule it since others have found it suitable.
Ok, sorry, since I am not a civil engineer my comments were subjective anyway. I didnt think the design was graceful for street design but didnt say it. Since NJ has a background and he felt the same I thought I should second it.
No Comments
Naveen,
You ur self have answered yr design deficiency.
Ask any body of yr ward engineering department and he will
tell you the sight distance and head light distance required for
vehicle at 40kms/hrs.
Otherwise ask some of your friends in China to do a simulation.
1.0 Go in vehicle, stop just before the top of yr crest.
2.0 Get down, walk upto the top.
3.0 See if any body is coming from the other side.
4.0 If yes wait and count the peds going underneath
5.0 If no go yr way after getting in the vehicle.
Pls let me know which location Mumbai has a "grown from the Road ped.pass?"
Nothing to offend or riducle.
nj
-nJ-
919462900144
www.nitinjhanwar.biz
IDS, NJ and Naveen - I disagree..
Naveen,
You seem to agree with IDS and NJ that zebra crossings are the ideal solution. Zebra crossings are convenient and cost-effective solution, but they surely cannot assure safety to pedestrians. This is true not just in Bangalore or India, but even in the cities with 'disciplined' traffic. That doesn't necessarily suggest that these subways are ideal.
NJ,
You make a important point about visibility. While you may 'sound' logical, I do not believe that the exaggerated steps are needed for motorists as in your post. Please note that if the roads are proper carriageways (with a median and sidewall for the road), there is no danger posed by the 'raised' road level.
As I have already said, these are not feasible close to the junctions, since we have seen the effect of the stormwater drain covers which are raised over the ground by about 1ft.
Das,
Your concerns of ventilation and security are sound. What solutions do you suggest for these? Would putting up enough fans and lighting be sufficient? Or do you see the need for putting 'costly' systems like AC and CCTV, even for 30ft long subways?
-Srivatsava V
-Srivatsava V
More On Ped Subways
NJ - I agree with Srivathsa & think that you are exaggerating.
In Mumbai, along the Western Express, Eastern express highways & also along the Andheri-Ghatkopar road, there are a few locations (cant remember exact areas) where the road rises up to allow for pedestrian subways & underpasses that are sub-sunk & accessed with only a few steps or a narrow road. The elevated road distance along the highways is kept large as speeds are much higher. The edge of the road is walled /barricaded.
Along NH-4, there is a similar underpass where the highway passes past a village somewhere near Chitradurga, also with barricaded sides.
In China, I have seen these at Guangzhou & at Pudong, near Shanghai. Having friends in China or not is irrelevant here, & I have quoted what I had seen & thought was a great idea as it was well utilized at almost all the locations.
Similarly, on Bellary road (BDA junction, etc), the road rises up & drops back to allow for pedestrian underpass as also vehicle underpasses, but the gradient is too steep & the disturbed road length is large.
Within the city, since speeds are not as high, the distances can be reduced & an optimum reached for safety on the road whilst making it convenient for pedestrians also.
As Srivathsa also mentioned, with a proper median & sidewalk barricades over the length of the road where it is elevated, none of the hazards that you mention are true.
I still cannot figure out why you say that the motorists need to worry about & count the no. of pedestrians passing underneath (Item-4 in your post). The motorists will be grade-separated from the pedestrians.
Your post suggests that you might still not have grasped what I am proposing.
IDS - Thanks & no offence taken.
Srivathsa - I mentioned earlier that disturbed earth must be well compacted before relaying the road. If this were done, the vehicles will not face problems. Storm-drains are cast & are solid, but the slopes up & down are never done up properly in most cases. If proper compacting & load-bearing surfaces are prepared before laying the road, it will be just as fine as the normal road.
You state that this will not be suitable at junctions. I dont think this is correct as the underpasses at BDA, Sanjaynagar, etc. on Bellary rd were all junctions previously. Also, the new plan for KR circle involves grade separation with one level well above the existing street level.
To provide ventilation & light, an opening can be made at the center median & the top covered with fibre-glass sheet. This will allow light through, but prevent rain water. I dont think there is any need for CCTV, but lighting will be required within the subway for night time.
What Das mentioned was in the context of the subways that are fully buried below street level when utilization becomes abysmal, unless pedestrians are forced to use them with no choice. If the subway/s are well utilized, they may not remain dirty & foul smelling & the need for forced draft fans may not be required.
Rest my case
nj
-nJ-
919462900144
www.nitinjhanwar.biz
Ventilation and security
The systems should ideally not be dependent on electricity and should be low (or no) maintenance. So breakdowns and power cuts don't affect the them.
Ventilation : Factories use natural ventilation systems that depend on pressure differences to move fresh air - hot air rises, etc. Like in these examples: http://www.tradeindia.com...
Option 1 : Fresh air comes in from the pedestrian entrances, hot air rises through the center. Maybe a vent embedded in the road itself, with a grating on the road surface ?
Option 2 : Air exits from one entrance, sucked in through another.
This is the limit of my gyan on this matter, and specifics will doubtless be provided by the system manufacturers.
Security :
This WILL be a big issue, and no simple solution exists. Here're a couple of links on this.
http://www.walkinginfo.or...
http://www.designcentrefo...
Technology (like CCTV) will be useful after an incident, and will act as a deterrrant only to a limited extent. You really can't have these in a few hundred subways. Also the problem of breakdowns, electricity, a subway-security force watching a bank of monitors somewhere 24/7, on call to rush to a trouble-spot. Too complex. The City Market subway actually has a guard through the day who keeps out hawkers and the homeless.
The best security anywhere is the presence of other people, of which there is no dearth in India. A radical solution would be to reserve one edge for hawkers and charge them a license fee. They however are only available maybe 9 AM to 7 PM. At night (even more radical) the edge can be used by homeless people.
Useful Information
Das,
Those links provide very useful information for subways. I think the first task is obviously to ensure that subways are used. If people find it convenient, they will use it & the need for security will diminish to a large extent due to the presence of people, at least through the day.
The subways near KBS & City railway station are in use by force rather than due to convenience as the median/s cannot be crossed + there are barricades at the sides. I dont think it will be possible to erect such preventive measures everywhere. So, a solution is required on how to get people to use them of their own will.
I think you are right - for wide roads, some form of ventilation will be required & there are worthwhile suggestions that could be referred.
17% Gradient
The logic is ok though at-grade is good.... but the dimesions are wrong.
You are talking about 17% gradient for vehicles...
Even in hilly terrains you have only 6-8% gradients ...
Sudhir
Gradient Can be Fixed !
Sudhir - thanks your input.
I used 10deg only as an example. Even if the gradient has to be no more than 6%, the disturbed road length will be less than 150' - much better than over 300' for fully elevating a road (to allow for at-grade pedestrian underpasses).
With your background, could you advise if I could take this up with BBMP ? I am concerned with the new underpasses being built, but remaining unused & deserted, probably in large part due to inconvenience/s of descending down & then ascending up, I think.
There may be other issues such as locational suitability, absence of barricades, etc., but I think it must first be designed to be convenient for use.
Naveen, Please change the
Naveen,
Please change the dimensions to have a grade of 3.3% maximum permissible for plain areas and take this up with BBMP. They cannot say no as the logic is being applied in Mumbai and Pune....
It is more cost effective then the normal pedestrian underpasses...
Sudhir, Thanks
Sudhir,
Many Thanks for Your Assistance.
I will soon make modifications on the sketch & post it here. I request you to please confirm if the dimensions, design, etc. are okay. Once we agree, I will pass it on to BBMP with a note explaining the need for a change.
Interesting concept
As Sudhirgota (kindly) pointed out, the slope needs to be less steep for the vehicles. Nitinjhanwar talked about sight distances - they are not needed if the road is wide and a barrier can be provided and the traffic is one-way each side of the barrier (adds to the cost, though). Of course, at-grade pedestrian crossings with greater ramp-up/down distances are probably the best.
Ped Subways - Sudhir, N
Sudhir - I have made corrections - please confim if it is okay now.
N - thanks your comments. I understand there will be some cost implications for retainer walls, etc. but I think designing it right for pedestrian convenience is more important. The present "completely buried" or "completely overhead" designs have few takers. With this design, I think it will have many more users & also reduce too much rise & fall for street levels, though I concur, at-grade subways would be the best.
The Ideal Infrastructure
The ideal arrangement of infrastructure for safety & convenience is as per sketch below. The pedestrian underpass is integrated with bus stops & is physically grade-separated from the road overhead. Such infrastructure is quite common in many of the re-developed chinese cities.
Unfortunately for Indian cities, this may be quite impossible as space constraints will come in the way, but can be included in the newer areas.
5 ft hump too high!
Naveen,
I am afraid a 5ft high ped crossing is gonna be too high and cars and busses will be doing camel back obstacle jumps..as it happens with dirt bikes..
The tallest one can afford will be 2-3 feet above the normal road level..this can also act as speed arresters for fast vehicles..this could be particularly useful for a merging traffic at an approaching signal free junction!
It Is Not a "Hump"
Blrsri,
There are so many magic boxes on Bellary road & other places too that require vehicles to rise up & then go down without interruption, just as they do at so many other bridges. So, why can't they do it elsewhere too if it helps pedestrians ? This is not a "hump" as you say, but it is similar to so many other such "bridges".
As mentioned previously, I have seen them in many places & liked their convenience & utility for pedestrians.
Ped Subways - Ltr to BBMP
Attached is a copy of the letter being sent to BBMP....
files/u139/BBMP_-_Pedestrian_Subway_Design_Ltr.pdf![](/files/u139/BBMP_-_Pedestrian_Subway_Design_Ltr.pdf)
The hump...
This is not a "hump"
I had the same thoughts... ROTFL!!!
Draw the pictures to scale Naveen. We are amatuers! I am sure every body is missing the numbers and looking at your nice drawings. (i did notice you have mentioned not to scale)
Ideal Infrastructure?? BBMP istyle??
Naveen,
The BBMP recently came up with a ped. underpass on Nrupatunga road, just next to a bus bay. After crossing the road by means of the underpass, the user had to cross the surface -level busbay to reach the bus stop. You know how well the underpass was recieved and how well it was ridiculed.
Without making any comments, I would like to remind you that this proposal is exactly the same. What is more useful is to connect the underpsass to four points - before and after the bus bay on both sides of the road. Or even simpler, put the same underpass before or after the bus bay!!
Isnt that more ideal - safe for the pedestrians, convenient for the buses and motorists on the road?
PS: What the BBMP built is useful on one-ways like NT road, but if only the bus bay was on the right side of the road!! Its not a bad idea, if land is available only on the right-side of a one-way street.
-Srivatsava V
-Srivatsava V
Nrupathunga Rd Subway
Srivatsava,
I had a look at the Nrupathunga rd pedestrian subway (& also one on Bellary road) before I had started this thread. In my opinion, the Nrupathunga rd subway is correctly positioned & provides access to the busbay across the street, but since it is completely below street level, it requires pedestrians to use staircases, which is inconvenient for many. Thus, it's not the same as the one shown on the sketches above. The one illustrated above is only a few feet below surface or almost at grade (with the street elevated to facilitate this), & is thus much more convenient for users.
Having two such subways or four entry /exit points just to avoid crossing the busbay would involve much more extensive work & may not be necessary at Nrupathunga road since it is midway along a single street. If other traffic (other than buses) respect the busbay & not use it, it will be quite safe for pedestrians crossing the busbay after emerging out of the subway since they only have to negotiate buses, if there are any.
The problem is that due to heavy traffic, autos, vans & even some cars tend to enter the busbay & make it inconvenient for pedestrians to cross it. The subway could have been lengthened & extended beyond the busbay to the sidewalk - this would have been safer.
What you previously highlighted was that multiple, integrated subways with several entry /exits were necessary at junctions to provide access from any street side to all other street sides at a junction, which I think is correct. But, are such multiple subways necessary for getting across a single street ?
IDS - I admit that the sketches convey the impression of a "hump". I will try to make a scaled sketch, though it might be more unclear due to the long road length involved !