Bitumen sheet with a protection against plant roots
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Solution Overview
Problem
Existing bitumen membranes for sealing building surfaces fail to effectively prevent plant root penetration, especially at edge zones, and organic root protection additives are washed out over time, posing environmental concerns and reducing their protective duration.
Innovation Solution
A bitumen membrane design featuring an upper layer without root protection additives, a lower layer with organic root protection additives, and a reinforcing layer, where the reinforcing layer is positioned between the upper and lower layers, and edge zones have a lateral edge layer without root protection additives, preventing additive washout and enhancing UV, weather, and walkability protection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If organic root protection additive is incorporated into the bituminous membrane, then root protection function is improved, but the additive is washed out over time and enters the environment
Solution Approach 1:
The bituminous membrane is divided into multiple layers: an upper bituminous layer without additive, a lower bituminous layer with root protection additive, and a reinforcing layer. This segmentation confines the additive to the lower layer, preventing washout while maintaining root protection function.
Solution Approach 2:
The reinforcing layer acts as an intermediary barrier between the lower bituminous layer (containing additive) and the upper bituminous layer (without additive). This intermediary structure prevents the additive from migrating to the surface and being washed out, while still allowing the root protection function to operate.
2Reliability
If continuous sealing layer is applied over bituminous layer with root-resistant additive, then root protection is improved, but coating with fine mineral particles becomes difficult
Solution Approach 1:
The membrane structure is segmented into distinct layers with the upper bituminous layer free of root-resistant additive. This segmentation creates a surface layer that is easy to coat with mineral particles while the lower layer provides root protection, resolving the contradiction between protection efficacy and manufacturability.
3Reliability
If root protection additive is distributed throughout the entire bituminous membrane, then root protection is improved, but additive washout at edge zones increases
Solution Approach 1:
The root protection additive is localized to the lower bituminous layer rather than being distributed throughout the entire membrane. This local quality approach ensures root protection where needed while preventing washout at edge zones, as the additive remains confined to the lower layer that does not form the exposed surface.
Data Source
Figure 1~2
Figure 3~4
AI summary
The present invention relates to a bitumen membrane with root protection (1) for sealing building surfaces, comprising an upper bitumen layer (2), a lower bitumen layer (3) and at least one reinforcement layer (4), the lower bitumen layer (3) and/or the reinforcement layer (4 ) contains an organic anti-root additive and the upper bitumen layer (2) contains essentially no anti-root additive, the reinforcing layer (4) between the upper bitumen layer (2) and the lower bitumen layer (3), within the upper bitumen layer (2) and/or is arranged within the lower bitumen layer (3). Also claimed is a method for producing the bitumen sheet (1), a method for sealing building surfaces with the bitumen sheet (1), sealed building surfaces obtainable using the method according to the invention, and the use of the bitumen sheet (1) for sealing building surfaces, in particular building roofs , interior and exterior areas of tunnels, canopies such as road canopies, bridges and swimming pools.