Precautions for construction of JS Polymer Cement Waterproof Coating

1. Inadequate Mixing

2. Excessive Water Addition

To improve permeability and adhesion, many manufacturers recommend diluting the coating with additional water during initial application.

3. Ambiguous Acceptance Criteria

Several factors can limit construction workers from standardizing the process and ensuring the waterproof layer meets desired performance. These include the number of application passes, the dosage per unit area, and the evenness of the base layer. In a scenario where the waterproof coating is diluted with water multiple times and applied according to the required number of passes, workers might still achieve the specified dosage per unit area, even if the base layer is uneven. While this may technically meet requirements, variations in real-world conditions can prevent the coating from delivering the expected effectiveness and longevity.

Research shows that the impermeability of JS waterproof coating is strongly influenced by material thickness. Within a specific thickness range, as the coating’s thickness increases, tensile strength decreases, while elongation improves. Using average thickness as an acceptance criterion helps mitigate the impact of such variables, ensuring both mechanical properties and waterproofing performance.

If the waterproof layer is insufficiently thick, it will compromise the overall waterproofing effectiveness and reduce the layer’s durability; conversely, if it is excessively thick, it may lead to unnecessary material waste. The recommended thickness for JS waterproof coating ranges from 1.5 to 2.0 mm, yet design and construction oversight often focus solely on the number of application passes, neglecting the final thickness of the coating. Consequently, it is essential that the waterproof design and construction process not only specify the number of layers and coats, as well as the dosage per unit area, but also clearly indicate the required thickness of the coating film, with the average thickness serving as the acceptance criterion for the waterproofing project.

4. Absence of Critical Components in the Carcass

Specific areas of the joints, including yin and yang corners and pipeline roots, are susceptible to cracking as a result of stress concentration. Typically, reinforcing the carcass can mitigate these issues. The placement of the reinforced carcass significantly influences its effectiveness. Ideally, positioning the carcass closer to the base layer enhances its ability to distribute stress.In many projects, workers often place the carcass arbitrarily, without proper consideration.