by Tom Bailey*
Road pavements quite often develop problems with depressions forming in the road surface either side of where culverts go under the roadway. In fact, big culvert areas can cause big problems for the road; sometimes known to locals as the ‘ski jump’!
There are often a number of contributory causes, including these factors:
- the pounding of heavy
traffic over time compacting
the fill each side of the
culvert structure - flood or heavy rains
washing fill away - fines being washed from
the fill into the culvert or
surrounding areas.
That washing into the culvert occurs through cracks, joints and bolt holes left after insitu construction of the culvert walls.
Although such penetrations are usually small, over time serious erosion can result, causing the road pavement above to lose support and become depressed, or in extreme cases it can even collapse.
These road surface depression problems have traditionally been very hard to solve by conventional methods – simply retopping the wearing surfaces often leaves continuingly remaining problems.
However, in the last few years Uretek has developed a lasting solution, now applied in many road situations, involving many types and sizes of culverts from small road pipe culverts to large, multiple box culverts on major floodways.
The unique Uretek solution involves raising and relevelling the road pavement with Uretek expanding structural resins and then deep injecting Uretek resins to expand into the fill at prescribed depths each side of the culvert.
Resupport is also extended to the fill immediately above the culvert structure, if required.
This method not only relevels the surface, but also densifies all the fill to give maximum support, thus absolutely minimising the chance of future problems.
Sometimes a whole section of a multiple box culvert can become undermined by floodwater. No matter how heavy, Uretek can lift such a section back into place and resupport it.
Uretek injections have been used up to eight metres down. So depth of fill presents little difficulty. Other advantages of the Uretek method are that it is very quick, with most such jobs taking only a few hours; and Uretek work can be done at night or at other times of low traffic volume.
For more information contact Tom Bailey on 0418 288 277, email tbailey@uretek.com.au or www.uretek.com.au
*Tom Bailey is Manager of Mainmark-Uretek
