Stackable Structural Cell With Quadrifoil Support For Hardscape
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Trees planted near hardscapes, such as roads and sidewalks, face challenges in root growth due to soil compaction from the weight of these structures, leading to reduced tree survival and growth.
Innovation Solution
The development of stackable structural cells with a quadrifoil-shaped support system that allows unimpeded root growth while providing structural support to hardscapes, preventing soil compaction, and designed to be lightweight, rigid, and injection-moldable, with features that prevent interlocking when stacked.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If hardscapes are placed close to trees to save space in dense urban areas, then land use efficiency is improved, but soil compaction increases making root growth difficult
Solution Approach 1:
The structural cell system divides the space beneath the hardscape into discrete cellular units that can be stacked. Each cell creates a segmented environment where soil and roots are contained within individual cells, allowing the hardscape to be supported while maintaining separate zones for root growth underneath.
Solution Approach 2:
The invention moves the root growth space vertically underneath the hardscape by stacking multiple cellular layers. This creates a three-dimensional root zone below the two-dimensional hardscape surface, allowing trees to access adequate soil volume without requiring additional horizontal space that would increase distance from the hardscape.
2Strength
If structural cells are designed with sufficient support members to bear hardscape loads, then load-bearing capacity is improved, but the volume available for root growth decreases
Solution Approach 1:
The support members are strategically positioned at specific locations within each cell to provide structural support where needed, while leaving the majority of the cell volume open and unobstructed for root growth. The quadrifoil cross-section provides localized strength at contact points while maintaining overall cell openness.
Solution Approach 2:
The structural cells utilize a composite design combining rigid support elements (such as quadrifoil-shaped members) with open cellular spaces. This composite structure provides both the necessary mechanical strength to support hardscapes and adequate volume for biological functions of root systems.
3Strength
If support members are stacked directly on top of each other to provide structural support, then vertical support strength is improved, but lateral stability decreases due to interlocking
Solution Approach 1:
The support members feature an asymmetric quadrifoil cross-section with four lobes oriented at specific angles. This asymmetric geometry prevents circular rotation and interlocking when cells are stacked, as the lobes of upper cells do not align with the gaps of lower cells, thereby maintaining lateral stability while preserving vertical support capability.
Solution Approach 2:
The quadrifoil cross-sectional shape is specifically designed to prevent interlocking between stacked cells before it can occur. The geometry of the lobes creates inherent clearance that anticipates and prevents the interlocking problem, allowing vertical stacking for support while maintaining lateral freedom of movement and stability.
Data Source
AI summary
Structural cells that are placed beneath hardscape. The cells are strong enough to structurally support the hardscape, effectively bearing its weight along with the weight of any load it carries. Furthermore, even though the cells are strong enough to offer structural support of a hardscape, the cells are also designed to be relatively lightweight, stackable, and open, allowing approximately 90% of their volume, or more, to be free volume that can contain uncompacted soil, tree roots, and the like. The cells achieve these attributes through a design that includes a flexible bottom frame, and support members. These support members have a cross-sectional shape that allows for axial rigidity while also preventing any interlocking between support members when cells are stacked. In one embodiment, this cross-sectional shape is a generally quadrifoil shape.