Plastic pipes reinforced by cross helically wound steel wires (PSP), which have exhibited excellent mechanical performance, consist of inner polyethylene (PE) layer, winding layer and outer PE layer. The winding layer...Plastic pipes reinforced by cross helically wound steel wires (PSP), which have exhibited excellent mechanical performance, consist of inner polyethylene (PE) layer, winding layer and outer PE layer. The winding layer is composed of two monolayers where steel wires are cross helically wound. An analytical procedure is developed to predict the short-term burst pressure of PSP as the monolayer is assumed to be elastic and orthotropic. The 3D anisotropic elasticity and Maximum Stress Failure Criterion are employed in the formulation of the elasticity problem. Good agreement between the theoretical results and the experimental data shows that the proposed approach can well predict the short-term burst pressure of PSP.展开更多
The geotubes have been widely applied in the engineering of land reclamation from sea. At present three kinds of material can be used to make geotubes: splitting film, fibrillated splitting film and multifilament. The...The geotubes have been widely applied in the engineering of land reclamation from sea. At present three kinds of material can be used to make geotubes: splitting film, fibrillated splitting film and multifilament. The geotubes made of these materials have their advantages and disadvantages. In engineering application to know the rule of forces change is very important. Based on geometry way, limit-filling height of geotubes is determined. Experiment in Pudong International Airport reflects that packing soil height of small-size geotubes will be smaller than that of large-size geotubes.展开更多
Microbiologically induced corrosion of concrete （MICC） and its protective coatings has a high eco-nomic impact on sewer maintenance and rehabilitation. A better understanding of the micro-organisms and the bio- geni...Microbiologically induced corrosion of concrete （MICC） and its protective coatings has a high eco-nomic impact on sewer maintenance and rehabilitation. A better understanding of the micro-organisms and the bio- genie acids that are generated in the sewer is essential in controlling the corrosion of concrete pipes and protective coatings. The role of succession of micro-organisms growth in the corrosion of concrete and protective coatings was evaluated in this study. Examination of various sewer pipe materials exhibiting various extents of degradation, including concrete, cement based and epoxy based coating revealed the presence of both organic and biogenic sulphuric acids. This reflects the activity of fungi and the thiobacilli strains. Organism growth and metabolism were strongly related to the substrate pH. Fungi were found to grow and metabolise organic acids at pH from 2.0-8.0. Whilst the thiobacilli strains grew and generated sulohuric acids at oH below 3.0. The successive growth of the organisms provides an impgrtant bearing in deyeloping improved strateegies.to better manage sewers.展开更多
基金the New Century Excellent Talents in University, MOE, China (No. NCET-04-0526)the Specialized Research Fund for the Doctoral Program of Higher Education, MOE, China (No. J20050398)the Key Project of Wenzhou (No. G2004034), China
文摘Plastic pipes reinforced by cross helically wound steel wires (PSP), which have exhibited excellent mechanical performance, consist of inner polyethylene (PE) layer, winding layer and outer PE layer. The winding layer is composed of two monolayers where steel wires are cross helically wound. An analytical procedure is developed to predict the short-term burst pressure of PSP as the monolayer is assumed to be elastic and orthotropic. The 3D anisotropic elasticity and Maximum Stress Failure Criterion are employed in the formulation of the elasticity problem. Good agreement between the theoretical results and the experimental data shows that the proposed approach can well predict the short-term burst pressure of PSP.
文摘The geotubes have been widely applied in the engineering of land reclamation from sea. At present three kinds of material can be used to make geotubes: splitting film, fibrillated splitting film and multifilament. The geotubes made of these materials have their advantages and disadvantages. In engineering application to know the rule of forces change is very important. Based on geometry way, limit-filling height of geotubes is determined. Experiment in Pudong International Airport reflects that packing soil height of small-size geotubes will be smaller than that of large-size geotubes.
文摘Microbiologically induced corrosion of concrete （MICC） and its protective coatings has a high eco-nomic impact on sewer maintenance and rehabilitation. A better understanding of the micro-organisms and the bio- genie acids that are generated in the sewer is essential in controlling the corrosion of concrete pipes and protective coatings. The role of succession of micro-organisms growth in the corrosion of concrete and protective coatings was evaluated in this study. Examination of various sewer pipe materials exhibiting various extents of degradation, including concrete, cement based and epoxy based coating revealed the presence of both organic and biogenic sulphuric acids. This reflects the activity of fungi and the thiobacilli strains. Organism growth and metabolism were strongly related to the substrate pH. Fungi were found to grow and metabolise organic acids at pH from 2.0-8.0. Whilst the thiobacilli strains grew and generated sulohuric acids at oH below 3.0. The successive growth of the organisms provides an impgrtant bearing in deyeloping improved strateegies.to better manage sewers.
