PATHLINK PROJECT SUCCESS The value of TripStop

TripStop would like to congratulate Mornington Peninsula Shire for using TripStop in its Pathlink project. TripStop is a cross shaped device that is encased in wet concrete, at intervals, to form articulation joints.

An Australian invention, TripStop separates the otherwise continuous concrete footpath into separate but linked slabs. It acts as a hinge that controls any displacement by combining the hinge with a shear connector. This reduces the likelihood of injury to pedestrians or cyclists.

Footpaths are usually built insitu as one continuous concrete mass. When subjected to forces caused by, for example, tree root invasion, soil movement or extreme temperature changes, the concrete cracks, either haphazardly or evenly at score lines across the width of the footpath.

After cracking has occurred the now separate concrete pieces are free to move independently and usually become misaligned or displaced. Because the gap between the footpath and a person?s foot when walking is so small ? 6mm is considered to be a threshold level for a tripping hazard ? it only takes a slight displacement to create a trip hazard.

Displaced concrete footpaths can cause enormous repair and legal costs, environmental damage and personal injury.

?There is cost factor in using TripStop,? said Tom Burk, Mornington Peninsula?s Pathlinks Project Manager. ?But it will save us enormous costs in the long term through less maintenance. We didn?t use it in one section of the path which has already lifted, so now we have to rip this up and will definitely be using TripStop this time.?

He said it is particularly useful when the path is close to trees and other vegetation, or the area is subject to reactive or unstable drainage conditions.

?The TripStop solution is radically different,? said TripStop inventor, Peter McLean. ?Rather than try to prevent roots from growing under pavements, which is not possible, or to make footpaths strong enough to resist trees, soil movement or extreme temperature changes which is also not practical, TripStop enables sidewalks to accommodate these forces, without causing misalignment or displacement, the danger to people. ?

TripStop makes footpath trip hazards a thing of the past. For further information visit www.tripstop.net

This is not an LG FOCUS Story but a Case Study

Source: Brisbane City Council, 2008 Internal Memorandum Progress Report- TripStop Concrete path Jointing System.

Case Study:

Step-faulting in concrete paths Where step-faulting of the footpath is likely to occur (this may be due to nearby large shrubs and trees), the ideal solution is to isolate the footpath from the roots by placing a 600 mm-deep vertical root-barrier alongside the path, (C&CA, 2006). The alternatives to this are to create some form of sheer connection between slabs that assists in preserving the surface alignment. Traditionally this has been done in thick concrete slabs by using: ? forming devices such as keyed joints, which are restricted to slabs of 100 mm or more in thickness ? dowels, which have large cover requirements and in thin slabs differential movement would cause spalling, or Technical Note, Transport and Main Roads, November 2014 11 TN132 Maintenance minimisation guidelines for walking and cycling facilities ? continuous reinforcing mesh which again requires cover and likely rusting at the shrinkage cracks. Brisbane City Council, (BBC, 2008) has been trialling a PVC joint former called ‘TripStop’ designed to create a rigid, articulated joint between adjoining concrete slabs between 75 and 125 mm thick. It is used in series with a minimum of five consecutive joints installed between the slabs adjacent to the tree as shown below. The additional supply and installation cost of ‘TripStop’ is around 10 percent of the total path cost but this is likely to be significantly outweighed by the savings derived from extending the life of the path. Figure 1:

The cross-sectional shape of TripStopTM PVC joiners

Figure1

Contact 0433 132 129

Mike Ramsey

[email protected]

TripStop Pty Ltd

www.tripstop.net