I. Comparison of Material Characteristics
1. Asphalt Waterproofing Membranes
Core Advantages:
Physical Properties: Adopting SBS/APP modified asphalt composite substrates (e.g., Ruide Model R901), with a tensile strength of ≥800N/50mm and an elongation at break of ≥40%, enabling resistance to base layer deformation.
Weather Resistance: SBS membranes have a temperature tolerance range of -25℃~90℃, while APP membranes range from -15℃~110℃, making them suitable for areas with extreme climates.
Construction Efficiency: A single membrane roll covers a large area (e.g., 10㎡/roll), and the hot-melt construction method can reach a speed of 50㎡ per hour, ideal for large-area projects.
Limitations:
Complex joints require additional layer treatment, and lap joints carry a high risk of water leakage.
Hot-melt construction requires open flames, posing safety hazards and causing environmental pollution.
2. Waterproofing Coatings
Core Advantages:
Adaptability: Liquid materials can penetrate the micro-pores of the base layer to form a seamless waterproof layer, especially suitable for irregular parts such as internal/external corners and pipe roots (e.g., Ruide PU-800 Polyurethane Coating).
Environmental Performance: Water-based JS coatings (e.g., Ruide JS-600) have a VOC content of ≤10g/L, have passed the China Green Building Material Certification, and can be used in drinking water tanks.
Construction Flexibility: Can be constructed on damp base layers (moisture content ≤15%), with convenient local repairs and a 30% reduction in construction period.
Limitations:
A protective layer is required for exposed use; otherwise, the weather-resistant service life is only 5-8 years.
Thick coating is prone to cracking, requiring 3-4 coats to achieve a total thickness of ≥2mm.
II. Key Bases for Material Selection
1. Project Type and Structural Characteristics
Roof Engineering:
Large-area Flat Roofs: Prioritize SBS modified asphalt membranes (e.g., Ruide R901). The hot-melt construction method forms a rigid waterproof layer with strong puncture resistance, suitable for accessible roofs.
Sloped Roofs or Irregular Structures: Use JS waterproofing coatings (e.g., Ruide JS-600) reinforced with glass fiber mesh. It can adapt to slopes of ≥20% and avoid the risk of membrane sliding.
Basement Engineering:
Water-facing Waterproofing: Adopt a composite system of APP membranes (e.g., Ruide R902) + cement-based permeable crystalline coatings, with a water pressure resistance of ≥1.5MPa to resist long-term groundwater erosion.
Backwater Surface Leakage Treatment: Use non-curing rubber asphalt coatings (e.g., Ruide NC-900), which can absorb concrete shrinkage stress and repair cracks of ≤0.3mm.
2. Environmental Conditions
Temperature Impact:
High-temperature Areas (e.g., Southern China): Select APP membranes or light-colored reflective coatings to reduce surface temperature by more than 15℃.
Low-temperature Environments (below -10℃): Self-adhesive membranes (e.g., Ruide R903) allow cold construction, avoiding the freezing risk of the hot-melt method.
Chemical Corrosion:
For scenarios such as chemical plants, prioritize acid and alkali-resistant APP membranes or epoxy coal tar coatings.
3. Construction Conditions
Construction Period Requirements:
Emergency Projects: Self-adhesive membranes (e.g., Ruide R903) can be applied immediately after peeling, allowing personnel access after 2 hours of surface drying, shortening the construction period by 50% compared to the hot-melt method.
Complex Joints: Polyurethane coatings (e.g., Ruide PU-800) can be applied by spraying, drying quickly in 30 minutes, suitable for areas with dense pipes.
Safety Restrictions:
No-fire Areas (e.g., warehouses, gas stations): Use water-based coatings or self-adhesive membranes to avoid fire hazards.
III. Design of Composite Waterproofing Systems
1. Synergistic Effect of Membranes + Coatings
Scheme 1: Apply JS coating (1.5mm thick) on the base layer → lay SBS membrane (3mm thick) → spray elastic acrylic coating (1mm thick) on the surface. This combination can improve crack resistance by 30% and extend the weather-resistant service life to over 15 years.
Scheme 2: Non-curing coating (2mm thick) + polymer self-adhesive membrane (1.5mm thick), forming a "skin-like" waterproof layer that can resist water pressure of 0.5MPa, suitable for dynamic structures such as subway tunnels.
2. Joint Reinforcement Treatment
Deformation Joints: First fill with polysulfide sealant, then apply polyurethane coating (2mm thick), and finally cover with a membrane reinforcement layer (width ≥300mm).
Wall-penetrating Pipes: Adopt the "one fabric + three coats" process (glass fiber fabric + coating), forming a frustum with a diameter of 300mm at the pipe root to ensure tight sealing.
IV. Brand Technical Advantages and Selection Recommendations
1. Characteristics of Ruide Products
Membrane Technology:
Self-adhesive Membranes (e.g., R903): Adopt a pressure-sensitive adhesive layer with an adhesive strength of ≥1.5N/mm, and can be constructed on damp base layers (moisture content ≤15%).
Root-resistant Membranes (e.g., R905): Have passed FLL certification, with a root-resistant layer thickness of ≥1.2mm, suitable for green roofs.
Coating Technology:
Water-based Polyurethane Coatings (PU-800): Have a tensile strength of ≥3.5MPa and an elongation at break of ≥400%, capable of covering cracks of 2mm.
Cement-based Permeable Crystalline Coatings (e.g., CCW-200): Have a penetration depth of ≥3mm, generating crystals when in contact with water to block capillary pores and achieve self-healing.
2. Recommended Composite Schemes
Economical Scheme:
Roof: SBS membrane (3mm) + acrylic coating (1mm), with a comprehensive cost of approximately 80 RMB/㎡ and a service life of 10-15 years.
High-performance Scheme:
Basement: Non-curing coating (2mm) + polymer self-adhesive membrane (1.5mm) + fine-aggregate concrete protective layer, with a water pressure resistance of ≥2.0MPa and a service life of over 20 years.
Green Building Scheme:
Water Tank: Water-based JS coating (2mm) + food-grade epoxy coating (0.5mm), have passed NSF certification, and can be in contact with drinking water.
V. Key Points for Construction Quality Control
1. Membrane Construction
Base Layer Treatment: Moisture content ≤9%, flatness error ≤3mm/2m, and cracks must be filled with sealant.
Hot-melt Process: Control the spray gun temperature at 300-400℃, ensure the membrane melting width is 8-10mm, and allow continuous asphalt strips to overflow from lap joints.
Joint Reinforcement: Add 500mm-wide additional layers at internal/external corners, and cut the membrane into a "cross" shape for paving at pipe roots.
2. Coating Construction
Proportion Control: For two-component coatings (e.g., PU-800), mix Component A and Component B at a weight ratio of 1:2, stir for ≥5 minutes, and use after 10 minutes of curing.
Coating Process: Adopt the "cross-hatching method" for 3 coats, with an interval of 6 hours between each coat, and ensure a total thickness of ≥2mm.
Curing Requirements: Cure at room temperature for 7 days, extend to 14 days in humid environments, and prohibit stepping during this period.
VI. Cost and Maintenance Strategies
1. Economic Comparison
Initial Cost: Membranes (60-120 RMB/㎡) ＞ Coatings (40-80 RMB/㎡), but the labor cost for membranes is 30% lower.
Long-term Cost: Coatings need renovation every 5-8 years, while membranes require replacement every 15 years; the total life-cycle costs of the two are similar.
2. Maintenance Recommendations
Regular Inspection: Use an infrared detector to check for hollowing before the rainy season every year, focusing on lap joints, drain outlets, and other key parts.
Local Repair: For damaged membranes, cover with patches of the same material (lap width ≥100mm); for cracked coating areas, remove the material down to the base layer and reapply.
