In ultraviolet cured-in-place-pipe(UV-CIPP)pipeline rehabilitation,resin performance critically determines repair effectiveness.Current UV-curable resins exhibit high volatile organic compound(VOC)emissions and inadeq...In ultraviolet cured-in-place-pipe(UV-CIPP)pipeline rehabilitation,resin performance critically determines repair effectiveness.Current UV-curable resins exhibit high volatile organic compound(VOC)emissions and inadequate post-cure toughness,which compromise fatigue resistance during service.To address these issues,we synthesized hydroxyl-terminated polyurethane acrylate prepolymers using diphenylmethane diisocyanate(MDI),polypropylene glycol(PPG),and hydroxyethyl methacrylate(HEMA).Fourier transform infrared spectroscopy(FTIR)confirmed successful prepolymer synthesis.We developed UV-curable resins by incorporating various crosslinking monomers and optimized the formulations through mechanical property analysis.Testing revealed that the polyurethane-acrylic UV-cured resin system combines polyurethane's mechanical excellence with acrylics'high UV-curing activity.The PPG200/MDI/HEMA formulation achieved superior performance,with a tensile strength of 55.31 MPa,an impact toughness of 22.7 kJ/m^(2),and a heat deflection temperature(HDT)of 132℃.The optimized system eliminates volatile components while maintaining high reactivity,addressing critical limitations in trenchless pipeline rehabilitation.The improved mechanical properties meet the operational demands of underground pipes,suggesting practical applicability in trenchless pipeline repair.展开更多
The city of New Owerri Nigeria is situated on a flat terrain and rainfall pattern is tropical high. The area is the seat of Government of Imo state and is crisscrossed by network of dual carriage roads adjoining exclu...The city of New Owerri Nigeria is situated on a flat terrain and rainfall pattern is tropical high. The area is the seat of Government of Imo state and is crisscrossed by network of dual carriage roads adjoining exclusive housing complexes. The road drainage system comprises open concrete drains on both sides of the cambered asphalt pavement. Much of the area is often flooded after a torrential rainfall and the flood water remains in the drains as long as evaporation permits. A study shows that the scenario is due to a number of factors, amongst which siltation and vegetal growth in the drains, poor drainage outlets are, very gentle terrain and poor maintenance culture. The standing pools of water in the drains sustain massive breeding of mosquitoes which constitute health hazard. Replacement of open concrete drains with properly designed trenches backfilled with permeable earth materials, sand, and overlay of grasses does not only reduce standing time of flood water but completely eliminates stagnant water. The method makes use of enlarged surface area of infiltration provided by the trenchless drain and millions of infiltration channels provided by the grass rootlets.展开更多
In this study,the research progress of trenchless piping technology for pipes with a large diameter was reviewed.The geological conditions of the sandbar in Xiangyang were taken into account in this study.This paper h...In this study,the research progress of trenchless piping technology for pipes with a large diameter was reviewed.The geological conditions of the sandbar in Xiangyang were taken into account in this study.This paper highlights the construction process management of the pipeline network project in Yuliangzhou Starting Area of Xiangyang City.Research was carried out in the aspects of optimizing mud ratio,controlling pipeline elevations,pipeline welding,and trenchless pipeline construction in limited spaces,stable support during pit excavation,and controlling the spacing between the junctions of two pipe segments.The research resulted in excellent outcomes and ensured safe construction,and the quality requirements were also met.展开更多
The rapid development of trenchless technology to repair the trenchless repair engineering precision and efficiency of consumption is put forward higher request, in the current research on the consumption forecast met...The rapid development of trenchless technology to repair the trenchless repair engineering precision and efficiency of consumption is put forward higher request, in the current research on the consumption forecast method cannot have satisfied current consumption of trenchless repair engineering control, be badly in need of an accurate and efficient method to forecast the consumption. Based on the BP neural network theory, this paper establishes the BP neural network algorithm model between the consumption of trenchless restoration engineering and its influencing factors, predicts the unknown consumption through the known limited number of samples, and verifies the feasibility of this method with an example.展开更多
The subsurface space in urban areas is an important asset.However,the information available on this environment is relatively poor compared to above ground information.This paper proposes a Building Information Model(...The subsurface space in urban areas is an important asset.However,the information available on this environment is relatively poor compared to above ground information.This paper proposes a Building Information Model(BIM)for underground applications as means to address this information gap.The creation and progressive update of BIM for a constructed artefact ensures that data on the structures is available and can be used throughout its lifetime.A BIM for underground applications integrates data on surface structures,such as buildings,and subsurface infrastructures,such as pipes,along with details of the surrounding ground,the associated soil and rock properties and groundwater regime into a single framework.This approach is demonstrated by applying it to trenchless construction operations,including a microtunnelling project for a new sewer.The data from this extended BIM concept can be interactively used with analysis packages to conduct risk assessments for new construction activities.It also shows how BIM for the Underground can be used throughout the planning,construction and post-construction stages of a project,and,importantly,how this information can be available for future projects.展开更多
Currently,there is a worldwide trend towards reducing emissions into the environment generated by human activities.Pollutant emissions into the atmosphere are a major measure of the impact on environment.The construct...Currently,there is a worldwide trend towards reducing emissions into the environment generated by human activities.Pollutant emissions into the atmosphere are a major measure of the impact on environment.The construction indus-try is a major producer of such emissions due in part to the magnitude of operations and the vast array of equipment.Increased urbanization has resulted in a need for the installation of an expanded underground network of infrastruc-ture that includes gas,water,wastewater,pipelines,power,and communications systems.Today,engineers are faced with engaging the construction option that not only provides the best cost advantage,but also considers environmental sensitivities to create the most sustainable solution.Reduction of pollutants such as carbon dioxide(CO_(2)),carbon monoxide(CO),nitrogen oxide(NO_(X)),total organic compounds(TOC),and sulfur oxide(SO_(X))have been identified by the United States Environmental Protection Agency as critical to sustainable development.This paper describes an approach for quantifying airborne emissions that is demonstrated through a comparison of two construction methods for installing a wastewater line.It was discovered that the option involving a traditional open cut method resulted in an overall average of about 80%greater emissions compared to trenchless pipe replacement.Thefindings of this paper should assist the utility construction industry in technology selection to minimize environmental impacts.展开更多
基金Funded by the National Natural Science Foundation of China(No.52473077)China Three Gorges Corporation(No.202403190)。
文摘In ultraviolet cured-in-place-pipe(UV-CIPP)pipeline rehabilitation,resin performance critically determines repair effectiveness.Current UV-curable resins exhibit high volatile organic compound(VOC)emissions and inadequate post-cure toughness,which compromise fatigue resistance during service.To address these issues,we synthesized hydroxyl-terminated polyurethane acrylate prepolymers using diphenylmethane diisocyanate(MDI),polypropylene glycol(PPG),and hydroxyethyl methacrylate(HEMA).Fourier transform infrared spectroscopy(FTIR)confirmed successful prepolymer synthesis.We developed UV-curable resins by incorporating various crosslinking monomers and optimized the formulations through mechanical property analysis.Testing revealed that the polyurethane-acrylic UV-cured resin system combines polyurethane's mechanical excellence with acrylics'high UV-curing activity.The PPG200/MDI/HEMA formulation achieved superior performance,with a tensile strength of 55.31 MPa,an impact toughness of 22.7 kJ/m^(2),and a heat deflection temperature(HDT)of 132℃.The optimized system eliminates volatile components while maintaining high reactivity,addressing critical limitations in trenchless pipeline rehabilitation.The improved mechanical properties meet the operational demands of underground pipes,suggesting practical applicability in trenchless pipeline repair.
文摘The city of New Owerri Nigeria is situated on a flat terrain and rainfall pattern is tropical high. The area is the seat of Government of Imo state and is crisscrossed by network of dual carriage roads adjoining exclusive housing complexes. The road drainage system comprises open concrete drains on both sides of the cambered asphalt pavement. Much of the area is often flooded after a torrential rainfall and the flood water remains in the drains as long as evaporation permits. A study shows that the scenario is due to a number of factors, amongst which siltation and vegetal growth in the drains, poor drainage outlets are, very gentle terrain and poor maintenance culture. The standing pools of water in the drains sustain massive breeding of mosquitoes which constitute health hazard. Replacement of open concrete drains with properly designed trenches backfilled with permeable earth materials, sand, and overlay of grasses does not only reduce standing time of flood water but completely eliminates stagnant water. The method makes use of enlarged surface area of infiltration provided by the trenchless drain and millions of infiltration channels provided by the grass rootlets.
文摘In this study,the research progress of trenchless piping technology for pipes with a large diameter was reviewed.The geological conditions of the sandbar in Xiangyang were taken into account in this study.This paper highlights the construction process management of the pipeline network project in Yuliangzhou Starting Area of Xiangyang City.Research was carried out in the aspects of optimizing mud ratio,controlling pipeline elevations,pipeline welding,and trenchless pipeline construction in limited spaces,stable support during pit excavation,and controlling the spacing between the junctions of two pipe segments.The research resulted in excellent outcomes and ensured safe construction,and the quality requirements were also met.
文摘The rapid development of trenchless technology to repair the trenchless repair engineering precision and efficiency of consumption is put forward higher request, in the current research on the consumption forecast method cannot have satisfied current consumption of trenchless repair engineering control, be badly in need of an accurate and efficient method to forecast the consumption. Based on the BP neural network theory, this paper establishes the BP neural network algorithm model between the consumption of trenchless restoration engineering and its influencing factors, predicts the unknown consumption through the known limited number of samples, and verifies the feasibility of this method with an example.
基金The authors gratefully acknowledge the financial support of EPSRC to Stylianos Providakis to enable him to undertake his doctoral studies,notably via the following grants:Balancing the impact of City Infrastructure Engineering on Natural Systems using Robots(EP/N010523)City(EP/K021699)and UKCRIC—National Buried Infrastructure Facility(EP/P013635).The visualisations shown in this paper were produced using SketchUp Pro(Inc,2016).
文摘The subsurface space in urban areas is an important asset.However,the information available on this environment is relatively poor compared to above ground information.This paper proposes a Building Information Model(BIM)for underground applications as means to address this information gap.The creation and progressive update of BIM for a constructed artefact ensures that data on the structures is available and can be used throughout its lifetime.A BIM for underground applications integrates data on surface structures,such as buildings,and subsurface infrastructures,such as pipes,along with details of the surrounding ground,the associated soil and rock properties and groundwater regime into a single framework.This approach is demonstrated by applying it to trenchless construction operations,including a microtunnelling project for a new sewer.The data from this extended BIM concept can be interactively used with analysis packages to conduct risk assessments for new construction activities.It also shows how BIM for the Underground can be used throughout the planning,construction and post-construction stages of a project,and,importantly,how this information can be available for future projects.
文摘Currently,there is a worldwide trend towards reducing emissions into the environment generated by human activities.Pollutant emissions into the atmosphere are a major measure of the impact on environment.The construction indus-try is a major producer of such emissions due in part to the magnitude of operations and the vast array of equipment.Increased urbanization has resulted in a need for the installation of an expanded underground network of infrastruc-ture that includes gas,water,wastewater,pipelines,power,and communications systems.Today,engineers are faced with engaging the construction option that not only provides the best cost advantage,but also considers environmental sensitivities to create the most sustainable solution.Reduction of pollutants such as carbon dioxide(CO_(2)),carbon monoxide(CO),nitrogen oxide(NO_(X)),total organic compounds(TOC),and sulfur oxide(SO_(X))have been identified by the United States Environmental Protection Agency as critical to sustainable development.This paper describes an approach for quantifying airborne emissions that is demonstrated through a comparison of two construction methods for installing a wastewater line.It was discovered that the option involving a traditional open cut method resulted in an overall average of about 80%greater emissions compared to trenchless pipe replacement.Thefindings of this paper should assist the utility construction industry in technology selection to minimize environmental impacts.
