Sandwichconstruction

Load-bearing and pressure spreading system

Pressure spreading systems spread the load of vehicle movements around the rooting area of the tree and eliminate/reduce soil compaction within the pit. Our sandwich construction replaces the foundation layer, creates a thinner base course and increases the available root growth volume. The open structure produces an open air layer beneath the pavement and prevents root damage to the pavement. Sandwich constructions are specially developed for situations where compaction of root space is to be expected due to traffic loads. 

MINIMIZING PAVEMENT LIFTING

Vehicular traffic over unprotected areas within the tree root protection zones of existing trees cause compaction of sub soils which leads to reduced voids within the soil structure. This reduces air and water transfer to the roots themselves which can ultimately lead to the root structure declining and the eventual loss of the tree. Because of the compaction the roots will search for air and water just underneath or between the pavement or asphalt. 

A sandwich construction is placed on a layer of tree soil, or structural soil, beneath the surface of the pavement. The system can be used in areas with existing or newly planted trees. Our pressure spreading system is also a good alternative in areas where it is not possible to use other subsurface structures or in areas with a high groundwater level.

We advise that the system should not be used within the zone of rapid taper (distance depends on the tree species, but to be sure ask a tree specialist when working within a 2 metre circle around the tree). To prevent the sandwich construction from lifting we recommend that you use our Tree Root Directing panels. Please remember that the situation could differ and depends on your expectations and objectives. Our experts will gladly help you find the best solution.

BENEFITS

  • Easy installation.
  • High load-bearing capacity.
  • Prevents tyre ruts.
  • Excellent tyre twist resistance.
  • Replenishes water supply to landscaped areas.
  • Unique and easy to use interlocking system.
  • No surface drains required.
  • Reduces ambient temperature around buildings (When compared to use of hard surfaces).

Find your urban tree solution