-
Pressure Resistance and Long-Term Reliability of PVC-U Drinking Water Pipes ——Stress Analysis and Life Prediction Based on GB/T 10002.1 Standard
1. Research Background PVC-U (Unplasticized Polyvinyl Chloride) pipes are ideal for drinking water supply due to their high strength, corrosion resistance, and no plasticizer migration (Figure 1). However, in high-pressure scenarios (high-rises, long-distance 输水): 50-year hydrostatic strength compliance is only 78% (GB/T 6111-2018) - 爆裂 rate of dn200mm pipes is 0.6 times/100km·year (domestic water company data) 2. Core Issue: Pressure Failure Mechanism 2.1 Failure Stages Through full-scale burst testing and creep testing, failures occur in three stages:  Elastic stage (0-10 years): Strain <2%, linear stress-strain Plastic creep stage (10-30 years): Strain rate 0.01%/year, crystallinity decrease Fracture stage (>30 years): Brittle fracture due to stress concentration 2.2 Key Parameters Parameter... -
Hydraulic Performance Optimization of Perforated Steel-Belt PE Composite Pipes for Drainage ——Cooperative Design of Infiltration and Drainage for Sponge City LID Facilities
1. Research Background Perforated steel-belt PE composite pipes, with a "steel reinforcement + HDPE matrix + regular perforations" structure (Figure 1), are core components for sponge city stormwater infiltration systems. Compared to ordinary PE perforated pipes, their ring stiffness increases by 50%, but engineering issues exist: Perforation rate >25% causes 22% strength reduction (GB/T 19472.2 critical value) 41% blockage rate after 3 years due to sediment (2024 MOHURD report) 2. Core Issue: Perforation Structure Conflict 2.1 Performance Parameter Conflicts Parameter Infiltration Requirement Structural Requirement Traditional Design Conflict Perforation rate (%) ≥20 ≤25 Performance inflection at 22-24% Hole diameter (mm) 8-12 (for infiltration)... -
Optimization of Anti-Leakage Structure and Construction Efficiency for Prefabricated Manholes ——Rapid Construction Technology Based on GB/T 23483 Standard
1. Research Background Manholes are critical nodes in municipal pipe networks, responsible for pipe maintenance, water level monitoring, and stormwater collection. Traditional cast-in-place concrete manholes face three major challenges (Figure 1): Long construction 周期: 7-10 days per manhole, accounting for 35% of pipeline project time High leakage rate: 42% of pipeline defects from joint leakage (2024 MOHURD data) Poor durability: 65% crack incidence after 5 years 2. Core Issue: Failure Mechanism of Traditional Manholes 2.1 Failure Mode Analysis Failure Type Cause Typical Scenario Joint Leakage Shrinkage cracks + seal failure Stormwater-sewage intersections Settlement Uneven foundation + low stiffness Soft soil...
