Stupidity of repairing potholes

[husoi]

According to British standards, all road surfacing will require a minimum of 40 wear surface.

For those less familiar with the build up of a road this is made of several layers.

Firstly we will have the existing ground leveled and compacted..

A sub-base made of aggregate, this depending on ground condition, can be from 350mm upwards in order to support the traffic load (with 32 tonne lorries as max frequent load)

Then a second layer of aggregate (optional) if ground condition requires extra load support.

between 100 and 150 mm base layer of asphalt, usually with content of aggregate of larger stones.

Then a coat of liquid asphalt (although has become a poor norm to "forget" to add this to surfacing opting for a richer base layer

Finally, the wear course that will have a minimum of 40mm.

This wear course will reduce it's thickness with time, depending on many factors.

 

Unless the road was built non-complying and the surfacing wasn't done properly this should last a few years.

 

When a pothole appears, this means the wear layer is now about 10 to 20mm. Because councils, or even highway authority take forever to repair them (although it shouldn't be repaired) the base and sub-base are usually also damaged.

The reason why it is a useless thing to do, repairing a pothole will be done with different materials than the normal road build-up and binding is usually inexistent. Adding to this, the wear layer will be now half of the minimum so the repair is to the same level as surrounding pavement, therefore less than the 40mm.

 

The only proper technical and economic solution would be the replacement of the section of road affected by the pothole(s) around 10m each side on the entire width of the road.

The issue with this simplistic approach is the ramp created between the new surface (40mm) and the 20mm existing surface. Although this can be mitigated.

 

Technically because it is the correct way of doing it for a longer lasting surface.

Economically because if you consider a 10 years span, it will require fewer mobilization of equipment, even if heavier equipment is required for a complete surfacing.

 

[KiwiBob]

Around Mansfield they repair them by chucking in a shovel full of asphalt and stamping it down with their foot!

[Simon Davey]

But if there weren't any potholes we'd have nothing to swerve around. 

[husoi]

4 minutes ago, Simon Davey said:

But if there weren't any potholes we'd have nothing to swerve around. 

For that you have the Scottish Highlands

[S-Westerly]

I've seen my local council "repairing " potholes by shovelling warm asphalt into the hole and rolling it with a garden type roller. Needless to say this bodge lasts weeks if you're lucky less if it rains. Our roads are now a total disgrace.

[Pie man]

Ah Good Ole British Standards, not to be confused with Council and Highways who have no standards 

[Nute]

The majority of potholes, at least around here, are where the road has been dug up for some reason and poorly reinstated. When the patch breaks down, usually due to water getting in around the joints to the original surface, the council just chuck a load of cold repair tarmac in every 2 months for the rest of time, at our expense. 

[S-Westerly]

That sounds about right. Complete cluster f**k.