Although often overlooked, mature tree canopies provide extraordinary benefit to the watershed. Whether it be collecting water on leaves or up taking water and providing evapotranspiration, millions of cubic feet of water can be prevented from running off a development simply by having a mature tree canopy. In urban environments, this can be incredibly challenging due to the compaction that occurs in the soils. While local code requires we plant trees, the health of those trees are often lacking, and the ones that do survive root system typically destroys the infrastructure around it. Because of this, we need a new approach. We at Construction EcoServices believe that in order to give a tree it’s best chance at becoming a viable Best Management Practice, we must give it an appropriate soil structure to root in.
Creating the Optimal Growth Zone for Tree Roots
Stratavault represents the sixth generation of structural cell and has been developed and patented globally by Citygreen® Systems. Stratavault builds on the experience gained through trials, projects and collaborations with industry innovators. The main drivers have been the need for:
- Root Growth
- Lower Installation Costs,
- Higher Strength,
- Reduced Transport Costs
The open, skeletal structure of the Stratavault matrix provides an optimal growth zone for tree roots. In excess of 90% of the total volume is available for tree root growth.
Stratavault has very generous apertures for root growth, without sacrificing the structural integrity of the matric. Stratavault apertures are large enough to permit some common conduits, services pipes and aeration systems to be incorporate within the structure.
Lower Installation Costs
Stratavault has been designed to achieve major reductions in installation costs. Units snap together quickly and easily, with labor times being drastically reduced.
Positive and secure connectors are a feature of the Stratavault patented design both vertically and laterally. Stratavault components are simple and fast to click together, producing an integrated matrix.
The Stratavault is a very highly engineered system that owes much of its incredible strength to a unique design (subject to numerous patents). So strong is this design, that the Stratavault is the world’s strongest large soil cell without relying on any steel bars (subject to corrosion), or glass reinforcement, or virgin resins.
Today, the Stratavault is available in:
- 30 series with 43.5psi Ultimate Load capacity
- 45 series with 65.2psi Ultimate Load capacity
We strongly recommend that specifiers check the Ultimate Load capacity from lab testing, of any product being considered for use beneath pavements. (That is the pressure at which the product fails when crushed in a laboratory. One of the popular US products fails at a pressure of just 21psi)
Stratavault modules are crush tested during manufacture as part of the rigorous quality control standards required by Citygreen.
Reduced Transportation Cost
Another unique design feature of the Stratavault system is the significant volume reduction for freight. With increasing scrutiny placed on use of fossil fuels and shipping costs, it was decided that this unit must achieve major volume reductions for shipping. The innovative nesting design is protected by worldwide patents and design registration, as are all other design features.
Trees in cities are almost universally seen as a very desirable, indeed hugely beneficial part of our lives. And probably the most critical factor in tree health and longevity, is the provision of enough quality soil for the tree roots. Providing for this volume of uncompacted soil beneath pavements is an issue that aborists, landscape architects and engineers have been debating for decades.
The modular Stratavault™ system employs advanced design geometry and reinforced copolymers to produce an incredibly robust, skeletal matrix. This matrix has been tested by Finite Element Analysis, as well as physical Ultimate Load tests at university. These test results have been verified by consulting engineers to provide adequate support for pavement loads.
Structural Soil Cells
Structural soil cells are modular units that assemble to form a skeletal matrix, situated below pavement level, to support the pavement load while providing a large volume of uncompacted soil within the matrix structure for root growth.
Compared to rock/soil matrix
Early research utilized a rock and soil matrix to provide support for pavement, while permitting some root growth within the pavement. Structural Cells have moved this principle forwarded by replacing the rock (80% of the total volume) with engineered modules (10% of total volume).
This sixth generation Root Cell has very generous apertures for root growth, without sacrificing the structural integrity of the matrix. Stratavault™ apertures are large enough to permit some common conduits, service pipes and aeration systems to be incorporated within the structure.
The open, skeletal structure of the Stratavault™ matrix provides an optimal growth zone for tree roots. In excess of 90% of the total volume is available for tree root growth.
Stratavault™ has been designed to achieve major reductions in installation costs. Units snap together quickly and easily, with labor times being drastically reduced. Positive and secure connectors are a feature of the Stratavault™ patented design both vertically and laterally. Stratavault™ modules are simple and fast to click together, producing an integrated matrix.
Using Stratavault™ can help clients earn additional points in the categories of: creating sustainable sites, water efficiency, energy and atmosphere, material and resources, indoor environmental quality, neighborhood pattern and design and green infrastructure and buildings.