Sprayed Polymer Waterproofing for Tunnel Joints
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional waterproofing methods for civil structures, such as tunnels, are time-consuming to install and prone to water leakage at panel joints, leading to reduced service life and safety concerns.
Innovation Solution
A waterproof covering system featuring a geotextile and geogrid with a synthetic polymer coating applied in situ, providing a continuous, joint-free barrier with enhanced adhesion and mechanical resistance, and optionally including a second flame-retardant coating for fireproof properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If conventional polyethylene panels are used for waterproofing, then the system provides good adhesion to irregular surfaces, but the installation becomes time-consuming and joints between panels become difficult to seal
Solution Approach 1:
The patent replaces the mechanical panel attachment system with a sprayed polymer coating system. Instead of manually attaching polyethylene panels to the shotcrete surface, a liquid polymer composition is sprayed onto the surface where it cures to form a continuous waterproof membrane. This substitution eliminates the time-consuming panel installation process while maintaining adhesion to irregular surfaces through the liquid application method that conforms to surface contours.
Solution Approach 2:
The patent changes the physical state of the waterproofing material from solid panels to liquid sprayable form. The polymer composition is applied in liquid state and then cures to form the final membrane. This parameter change from solid to liquid state enables continuous application without joints, dramatically reducing installation time while the liquid nature allows it to conform to irregular surfaces effectively.
2Strength
If conventional polyethylene panels are used for waterproofing, then the system provides good adhesion to irregular surfaces, but the joints between panels are difficult to seal completely
Solution Approach 1:
The patent merges the entire waterproofing system into a single continuous membrane formed by sprayed polymer coating. Instead of having separate panels that require joint sealing, the liquid polymer is sprayed to create an unbroken, continuous layer across the entire surface. This merging of discrete panels into a unified continuous membrane eliminates joints entirely, thereby eliminating the reliability issue of joint sealing while preserving adhesion to irregular surfaces.
Solution Approach 2:
The patent changes the physical state of the waterproofing material from solid panels to liquid sprayable form. The polymer composition is applied in liquid state and then cures to form the final membrane. This parameter change from solid to liquid state enables continuous application without joints, dramatically reducing installation time while the liquid nature allows it to conform to irregular surfaces effectively.
3Reliability
If shotcrete layer is used for waterproofing, then the system provides low porosity and good waterproof covering, but the installation process becomes multi-step and time-consuming
Solution Approach 1:
The patent extracts the waterproofing function from the multi-step shotcrete process and consolidates it into a single polymer spray application. While shotcrete provides waterproofing through low porosity, it requires multiple steps including surface preparation, shotcrete application, and curing. The polymer spray system extracts and delivers the waterproofing function in one application step, reducing installation time while maintaining or improving waterproofing performance.
Solution Approach 2:
The patent replaces the mechanical shotcrete projection system with a polymer spray application system. Instead of projecting concrete at high velocity and allowing it to cure, the liquid polymer is sprayed and cures faster to form the waterproof membrane. This substitution reduces the number of steps and overall installation time while achieving the same or better waterproofing effect.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system offers improved waterproofing performance, reduced installation time, and increased durability, preventing water leakage and providing fireproof protection while maintaining mechanical integrity under external loads.
Implementation Method 1
a first coating layer of synthetic polymer continuous coating that from a liquid state in which said synthetic polymer is applied by in situ projection to cover said second face of said geotextile, said geogrid and said anchoring means, said first coating layer is cured to a solid state
Implementation Method 2
The geotextile is made of a nonwoven fabric, punched with a first face smoothed by thermofusion
Data Source
Figure 1~2
Figure 3~5
Figure 6~9
AI summary
A waterproof covering system (1) for covering a surface comprising a geotextile (2), a geogrid (8) arranged on the geotextile (2). The system further comprises anchoring means (10), comprising a nailing member (12) and a retaining plate (14) operatively associated thereto. The retaining plate (14) comprises a plurality of through holes and is arranged such that in the operation position of the anchoring means (10), the retaining plate (14) overlaps the geogrid (8). Finally, a first coating layer (18) of synthetic polymer forms a continuous coating is applied by in situ projection. The first coating layer (18) covers the geotextile (2), the geogrid (8) and the anchoring means (10), and cures to a solid state to provide a positive fit connection between the first coating layer (18) and the anchoring means (10). The invention further relates to a civil structure and a method for forming a waterproof covering system.