Best solution for Roads in monsoon region?

[koli]

I see quite a good talent present on CE. I want to explore the possibility to find solution here.
Most roads in monsoon region (Indian subcontinents) damage heavily due to rain and sub standard quality of material used. We do see that there are several options like Tar (few different types), Concrete, Concrete bricks, etc. While pure concrete roads looks better options, due to cost and implementation time those are not that popular in most countries. I know that in US, UK and many countries Tar roads are more popular and those are not as bad in the rainy season.

Question is what is the real reason why these roads are giving up during monsoon?

What is the alternative to existing type of tar roads?

What is the exact problem in existing quality of material used in tar roads?
What are the other alternatives?

[ash]

We have the same problem here in Malaysia. There are loads of potholes on roads, and they are barely visible when it rains.

Some of the roads are concrete, but most are tar. The thing is, the potholes appear on some tar roads, while others is it does not. One needs to look at the consistency on how roads are built.

Other than the material used, I believe the ground the roads are build on is a factor. In highways, I'm pretty sure they hardened the ground first somehow, perhaps by putting loads of gravel. But on small streets, they wont do this often. Ive noticed that they fix potholes caused by rain/car erosion by layering it with tar again. However, the new layer somehow "sinks" into the ground, creating a new pothole.

I also think drainage plays a role. Water settling too long on the road may cause some damage.

[koli]

I know water is main reason to damage tar roads, but what i dont know is how it is managed in US, UK and other countries. There is some chemical composition or method which is different.

Any Chemical / Civil engineer want to comment with their expertise.

[BOBBY]

anyone has any idea about design parameters of roads,
such as
1.angle of slant of roads to either sides (to counter rain water damage)
2.Parameters at the turnings .
(i found lot of holes formation at the turnings)

I observed rain damaging the edges of roads and gradually expanding to all over.How to take care of edges?any tech that can be used to minimise the damage.

[gohm]

We don't have a monsoon time here in the US(nor UK). Instead some areas have damage due to frost heaves. These are bumps that are formed by the ground being thrust upwards from water freezing. Formula, base structure & compaction are all factors in road construction quality. Our roads are crowned (sloped away to both sides) and many have rain grooves to help expedite water run off. Many bridges & overpasses will use metal decking. Traffic itself is the largest cause of road surface damage due to high stress factors.

[dhaval23]

In developed countries there are better surface or storm water or rain water drainage system. The roads are well drained and have sufficient culverts to allow the gravity flow of water. In developing countries like india roads are not provided with sufficient culverts, due to which they act as an earthen dam. Water in turn finds its way inside this earthen dam, creating voids like cavillary tube and get ruptured on passind on heavy vehicles. This lead to creation of local pot holes where road, base and sub base fails in carrying the vehicle load.

Other reason is mentioned by other of contractor not able to compact properly base and sub base of the road. Material used in road construction also play important role.

According to me many of this problem can be overcomed if the drainage system in designed properly.

[The_Big_K]

Thanks for the information, Dhaval. Designing a drainage sytem could be a solution for the new roads. What do you think we can do for the existing roads?

There must be a solution.

[gohm]

Installing culverts in existing road decks is a fairly simple and cheap thing to do.

[ash]

Originally Posted by gohm

Installing culverts in existing road decks is a fairly simple and cheap thing to do.

But where would the water flow after? I think drainage systems takes some planning. Its certainly very hard to install a drainage system in a super congested area without disrupting traffic, as well as whatever already exists right next to or under the roads, such as power and telecommunication lines, or foundations of other buildings.

[gohm]

Don't you have storm drain infrastructure?! In the country it easily collects into ponds are streams. If there is no water runoff management system like storm drains or the like in the city then that certainly is the problem! The cart is before the horse.

[ash]

Originally Posted by gohm

Don't you have storm drain infrastructure?! In the country it easily collects into ponds are streams. If there is no water runoff management system like storm drains or the like in the city then that certainly is the problem! The cart is before the horse.

Oh.. aren't we assuming there is no (or very ineffective) drain infrastructure for existing roads? *scratches head in confusion*

[gohm]

Yes, I assumed that there may not be proper drainage infrastructure because of your post, though I initially guessed the drainage system was inpace first as it should be:

Ash- "But where would the water flow after? I think drainage systems takes some planning. Its certainly very hard to install a drainage system in a super congested area without disrupting traffic, as well as whatever already exists right next to or under the roads, such as power and telecommunication lines, or foundations of other buildings."

This would imply the infrastructure is not adequate or inplace. If that is accurate, then that problem would need to be addressed before the pavement issue. I had guessed the drainage system was there and so then normally with road expansion it is a simple matter of tying into the system & adding culverts. Working around buried cables and diverting traffic isn't to bad either, paving contractors do it all the time.

[ankur8819]

I don't know about the technical complications involved but yeah all i know is the material being used to make roads these days by the contractors and all is of vry low quality..I just found this out in my area only The road was constructed some months ago.and now as its raining here the new road is in pieces..
So the root cause behind evrythng is Corruption..
everyone frm The highest CIvilor PWd enggineer to the contractor is corrupted !!!

GOd Plz save my country from these TERRORISTS!!!

[sauravgoswami]

HI mates!!!....the situation in Mumbai is somewat diffrent than other cities in India,BMC(municipal corporation of Mumbai)are doing there job they have started making concrete roads and paver blocks at junction,as water clogging Rain water harvesting and other schmes have been introduced,KOLI i wud like you too observe the positives after all u shud be proud of this magical land

[mayurpathak]

*bump*

Oh boy how did I miss this thread. I'm a Civil Engineer after all. Anyway, building Concrete road is very good for the soil which has minimum internal movement. When the road is constructed, these guys make all attempts to consolidate the soil under the bed so that it doesn't allow water to seep below it. Other wise due to internal erosion, a part of the road may subside down leaving the Cement road permanently damaged. Moreover its very costly to construct this road as well as very time consuming.

Saurav I see you are from Mumbai. Look at the WE highway due to the contractor's inability to construct the road fast. He can't do much either because if he speeds up, there is every chance we will get a bad quality Cement road at a very high cost.

I guess Tar roads are the best as long as they are laid properly. Multiple layers with various size rubble might do the trick.