[stanjohn123]

Recently our Village had extended our roads using Interlock on either sides of the road. This was done for a total stretch of 7.5 Kms from Munchirai to Kozhivilai( Kanyakumari District ).



For this, first they dug up on either side a width of 3 feet ( Approx ) and depth of 3 feet using an Excavator. Then they created a 1 feet wide x 2 feet height concrete fence in the border as seen here.



Then the gap between the road and concrete fence, they filled it up with small rocks and on top of that they put M-sand ( Rock powder ) to level it and finally placed the Interlock on top of them and then hit it in place with a machine so that it seats properly.



This is definitely a very expensive way to expand the width of our roads than just using regular Tar. That too such a construction was done on a 7.5 Km stretch. Of course I am glad that the roads have extended ( so no more broken mirrors for me or car falling into a ditch ) but how good or bad is this technique ?



I have few questions as below

1) How safe is it for bikes during a rainy day ?

2) Is there any justification for the huge amount of public money they must have spent in doing this ?

3) If this is a great novel idea, why aren't other cities and towns following the same model ?

4) Is it safe for cars while riding at 60-80 Kmph over the road and interlock at the same time ?

5) How does it the rubber compound of our tyres react with the concrete Interlocks ? Tyres are more Grippier and softer on Tar if my understanding is right on this.

[anandhsub]

I guess this is mainly used to drain rainwater faster. Was there a problem with waterlogging earlier?

I have seen this used on some ghat roads ( Kodaikanal I think?). So if it works there then I think it should be fine. But I hope this is still a work in progress. That gap between the road and these tiles which has been filled with stones will definitely cause skidding.

[BLACNWYTE]

While this has certain advantages like, long life and better load bearing capacity the biggest drawback will be the lack of grip when wet. Interlock concrete blocks are notorious for losing grip while wet and there need not be a layer of water on top of them for smaller vehicles to skid and slip. I have faced a couple of heart in mouth situations with my Activa during monsoon rains on these roads. I was doing less than 40 kmph since it was raining. Also the road/tyre noise is horribly loud with a loud humming sound if you go above 50 kmph on these.

Since they offer more life, the PWD and other authorities are repairing the damaged asphalt section with these deathtraps everywhere. And people too are asking for these since they will have a motorable road for more than 6 months at a stretch, in spite of the hidden danger.

[nagr22]

Originally Posted by stanjohn123

I have few questions as below

1) How safe is it for bikes during a rainy day ?

Are you sure this has been done to let vehicles drive on it? To me it looks like they have constructed footpaths for people to walk. Please get it clarified from your area administrators about its purpose. It shouldn't become the case where two wheelers end up using the space meant for pedestrians like it happens in our cities

Regarding safety, I've seen these kind of surfaces laid in some of Bangalore roads and they seem to be perfectly fine for two wheelers to drive on. It can be dangerous if few stones get dislodged leading to bumps or holes which might make a two wheeler loose balance.

[stanjohn123]

Originally Posted by anandhsub

I guess this is mainly used to drain rainwater faster. Was there a problem with waterlogging earlier?

No, there was no water logging issue. But the earlier road was narrow for 2 vehicles to cross each other. Either 1 or both vehicles had to get off the road to pass each other. But it used to be uneven and deep so some cars like the Verna bottom out pretty badly.

Originally Posted by BLACNWYTE

While this has certain advantages like, long life and better load bearing capacity the biggest drawback will be the lack of grip when wet.

This is what I am worried about mostly too. Grip during wet will be horrible.

Originally Posted by nagr22

Are you sure this has been done to let vehicles drive on it? To me it looks like they have constructed footpaths for people to walk. Please get it clarified from your area administrators about its purpose. It shouldn't become the case where two wheelers end up using the space meant for pedestrians like it happens in our cities

Pretty certain this is widening the road because the older road was too narrow for 2 vehicles to pass freely in opposite direction. It's definitely not a foot path. Also on 1 side the Interlock is 2 feet in width while on the other side it's just 1 feet wide.

[lamborghini]

In Mumbai, over time, many of these interlocking pavers have gotten loose over time, chipped, etc. which can be a hassle for two wheelers & pedestrians.

[ninjatalli]

Originally Posted by stanjohn123

Pretty certain this is widening the road because the older road was too narrow for 2 vehicles to pass freely in opposite direction. It's definitely not a foot path. Also on 1 side the Interlock is 2 feet in width while on the other side it's just 1 feet wide.

Just to add - quite a few parts of Mumbai have this setup for the footpath sections. The footpath on our street had this till recently when it was dug up by BMC for laying storm water drains.

But I have seen roads with this inter-lock system too (across Mumbai), so I guess it can be for both purpose. Considering it's at the same level as the tar road, I'd think they did it for both purposes - use it as road during traffic; while otherwise people can use it for footpath purpose (or parking their vehicles).

[2cents]

In Kerala this is used in short stretches (like 5-20 m) where there is frequent road repair due to the underground drinking water pipes bursting every now and then. Road grip can be managed by using the right kind of interlocks, but the real trouble I've noticed is that interlock paved stretches do not have the same elasticity (is that the right word!) of a tarred road. Under frequent or heavy traffic the stretch is likely to buckle up easily making it a traffic bottle neck.

[Night Raven]

I hate it when they use these tiles to repair damaged patches of road. Nowadays it has become the norm in our state especially in areas where road gets damaged repeatedly. Durability seems much better, but it feels very rough compared to normal tarmac. Road noise becomes too much and the car just jumps about if driven in good speed. Also, I am always worried about losing traction and skidding when it is wet.
Reminds me of this video

https://youtu.be/fn8A8UYbYmA

[itwasntme]

We have similar interlocking paver blocks in our gated community, which have proved resilient throughout the 7 years we have been here. I must admit though that they were definitely laid much more scientifically and robustly than the pictures you've shared.

One advantage is that there is minimal heavy vehicle movement in our estate. Overloaded HGVs will definitely churn up these blocks especially if they are not well set. I remember a tanker water unloading point which had got badly rutted, and it was changed to tarred road by our RWA.

[Eddy]

I've seen this in Delhi, but being used as a footpath and mostly separated from the road via a drain. Even though it hardly sees motor vehicle traffic, it does not last beyond a year or two.

In your case, the life may be even lower given that it will see a lot of traffic and much more rainfall than Delhi (?).

[ABHI_1512]

These Paver blocks are mainly used for decorating footpaths for pedestrian use. Have seen these blocks being used as part of residential streets and lanes as well. In cities like Guwahati, these paver blocks are used extensively for streets with low and slow vehicular traffic.

Footpaths in many parts of cities like Calcutta and Delhi are beautified with these kind of paver blocks. These blocks are great for walking streets as water doesn’t hold and the pavements dry out soon.

But the real problem starts when these are used for roads with high density of vehicles like in the case above. Deviations start after some time and gaps begin to widen by the pressure of vehicles running over. In the worst case I have even seen Bikes taking a hit from a loose block and meeting with accidents.

Heck, even car underbody also gets hit by some uneven block which juts out and even damaging the tyre rim or alloy. Cars have met with accidents on narrow paved roads as well. Whoever thought of using paver blocks as skirting on a proper road is only putting the motorists at risk while some contractor makes money.

[Thermodynamics]

I’m surprised they did this in a village at such scale.

Originally Posted by stanjohn123

I have few questions as below

1) How safe is it for bikes during a rainy day ? .....

To your questions, my two cents

1) Bikes: Should be safe, most bicycle lanes in Europe are very similar. They do lodge off, periodic maintenance is the norm.

2) Public money: as you know, elections are ahead

3) Why not in other cities: track your leader

4, 5) Cars: are not safe. I guess this is likely to get demarcated and reserved for bicycles/pedestrians.

[ninjatalli]

Originally Posted by ninjatalli

Just to add - quite a few parts of Mumbai have this setup for the footpath sections. The footpath on our street had this till recently when it was dug up by BMC for laying storm water drains.

But I have seen roads with this inter-lock system too (across Mumbai), so I guess it can be for both purpose. Considering it's at the same level as the tar road, I'd think they did it for both purposes - use it as road during traffic; while otherwise people can use it for footpath purpose (or parking their vehicles).

This is a perfect example of what I was talking about - the interlock has been used for the roads and footpaths. Scenes like these are common in Bombay. The main lanes of the roads are tar and/or concrete.

[arun_josie]

Originally Posted by stanjohn123

1) How safe is it for bikes during a rainy day ?

4) Is it safe for cars while riding at 60-80 Kmph over the road and interlock at the same time ?

5) How does it the rubber compound of our tyres react with the concrete Interlocks ? Tyres are more Grippier and softer on Tar if my understanding is right on this.

This is not new in Kanyakumari dist. I remember people had raised concerns about safety on such roads during rainy season. But the authorities involved just went ahead about their business as they had a long term agreement signed with a vendor.

I am always extra cautious(especially when it rains) while crossing the interlock stretch in aralvaimozhi.

https://www.youtube.com/watch?v=AQgFz2v91lA