good points. given the dimensions, they can only work at the intersection of a major road with a minor road. it will be an under engineered solution for a junction of two major roads. that was always the danger, that they would use the same hammer for all surfaces. they have to have a clear idea about what they are trying to achieve and test if these pre-cast underpasses suffice towards that end. it should not be that just because they can do pre-cast they force it on all roads. i was under the impression that solid 2x2 system between the city and hebbal, was what they were after. (if done properly, 2x2 systems can do atleast 40K PCUs/hour). then suddenly they started talking of 10 lanes between CBI and hebbal. shows they have no clue what they are talking about. nevetheless might be worthwhile to map where these are situated. and test if they pass the consistency tests. now since they are interventions on junctions, it might be worthwhile to see if these result in serious improvements to junctions like we discussed before, or if they are just cut and fill types. any chance we get look at the designs for all these junctions? need to track those features in DH. will post them later.

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From todays DH:

It’s been just over a month Bruhat Bangalore Mahanagara Palike threw its ‘innovative’ underpass near Cauvery theatre junction open for vehicle flow. It is already witnessing traffic jams: Traffic from Sadashivanagar (from Bhashyam Circle) is getting clogged at the mouth of the underpass, especially during peak hours.

Autorickshaws, two-wheelers and BMTC busses jostle to pass through the underpass. So much so that BBMP was forced to put up a road hump (produced from South Korea) to check vehicle speed and to prevent accidents. The big question here is: What would be the scene in coming days as the number of vehicles increase? “The present traffic between Bhashyam Circle and the Cauvery theatre junction is 5,500 passenger car per unit (PCU). And it’s going to grow in coming days. It will definitely turn into a major traffic bottleneck in coming days,” a traffic expert, who is part of the BBMP technical advisory team, noted.

For the existing traffic volume on this stretch, the width of the box should have been 7.5 metres and there should have been two lanes for the underpass. No where in the world such a small box is used. A 4.5 metre width box is used for pedestrian underpass. The underpass is too steep, which again contributes to slow traffic. If in case a bus breaks down below the underpass, the entire traffic comes to a standstill, fear experts.

“There is very slow movement of traffic at the entrance, as the width of the box is small (4.4 metres). So our buses are moving slowly,” BMTC Divisional Traffic Engineer Chandapur said.

Now that the BBMP has proposed to replicate the model at 44 “critical” junctions across the City in 2008-09 and much more in future, experts say, “The BBMP refuses to learn from its experiences. Though City planners have been suggesting implementation of long-term solution, it is doing just the opposite.”

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The underpass has one good feature. It is a temporary detour if the BBMP build a ramp/magic box on bellary road (uni-directional) to avoid the U turn. While this is being built the U-turn will engage most of the traffic.

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From the day one, i was wondering how will BBMP, make a snake swallow the dragon. In kannada there is a famous song from Shishunala shareifa "Kodagana Koli Nungitta". With the present size of the Magic Boxes, there needs to be some serious Magic for it to work for long time. As suggested in other posts BBMP, should increase the width of the Magic boxes to the breadth of the road, for the traffic to be smooth. Anyway Bangalore's magic box solution should not turn out to be one of those famous flyovers with a signal on top of it, you know which flyover i am taking about. (Richmond).... -- Anyway Cheers

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you are right;

though the idea of construction of underpasses is excellent, its implementation should have been better.

The underpasses should be

 - wide enough to all two big vehicls pass simultaneously

 - should be constructed of cement

thanks

Srinath Heragu

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paper reports today point to clogged drains at the cauvery underpass..its just the pre-monsoon showers now..

This has already led to huge jams and damage to vehicles which risked to wade through the waters..BBMP says its a small issue!

Is it really a small issue? or is it something that overzealous engineers completely overlooked?

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Magic box underpass is just a stop gap solution, but the BBMP thinks of it as the magic mantra. They have started thinking of it as the magic wand which will take away all the traffic woes.

Just take a look at the anand nagar underpass and you would wonder what kind of vehicles are supposed to pass thru that drain. it is so narrow and the roof is so low.

Moreover, the magic boxes are supposed to take less time (3 days ?) to be setup and that is why they use precast technology (which has its limitations on the size of the elements, hence limiting the width of the boxes). But since BBMP takes 3-4 months to complete each underpass, why use the precast elements and not use the standard method, as you are anyways taking the same time and also building narrow passes. Using the standard method they would atleast be able to make wider passes.

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The court has given a notice to BBMP over a PIL demanding stay over magic boxes.

Source: TOI article.

-Shastri

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now that BBMP has planned for so many magic boxes I would like to reiterate my earlier points & echo others points

1. magic boxes for traffic in each direction should be wide enough (minimum wdth)  so that two (2) VOLVO buses can travel abreast at moderately high speeds

2. magic boxes should havehigh ceiling so that there is a clearance of at leat 5 feet from the top of a VOLVO to the ceiling

3. the road system near any magic box should be planned in such a way so that any vehicle with an extraordinarily big height should be able to go around or over the magic box (necessarily in a cumbersome way) in the desired direction

4. the drainage should be such that there is no clogging during monsoon; they can be made slopingon eitherside so that water flows down easily

5. pedestrians can be provided safe passage alongisde the vehicular traffic

6. the mgic boxes should be curved and aesthetically pleasant

7. some water outlets for fire fighting should be provided

8. IN MAJOR COMMERCIAL AREAS LIKE MAJESTIC magix boxes SHOULD REPLACED BY FLYOVERS

thanks

Srinath Heragu

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The tolgate underpass has been lying there for almost

2years now.the work stopped again a few days earlier

and fights about govt. sanctioning appropriately.something must be done about this

evrytime u want to go to vijaynagar and its outskirts you get to ride/pay more!

peace out

mas*

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