Waste plastics,such as waste polyethylene terephthalate(PET)beverage bottles and waste rubber tyres are major municipal solid wastes,which may lead to various environmental problems if they are not appropriately recyc...Waste plastics,such as waste polyethylene terephthalate(PET)beverage bottles and waste rubber tyres are major municipal solid wastes,which may lead to various environmental problems if they are not appropriately recycled.In this study,the feasibility of collectively recycling the two types of waste into performance-increasing modifiers for asphalt pavements was analyzed.This study aimed to investigate the recycling mechanisms of waste PET-derived additives under the treatment of two amines,triethylenetetramine(TETA)and ethanolamine(EA),and characterize the performances of these additives in modifying rubberized bitumen,a bitumen modified by waste tyre rubber.To this end,infrared spectroscopy and thermal analyses were carried out on the two PET-derived additives(PET–TETA and PET–EA).In addition,infrared spectroscopy,viscosity,dynamic shear rheology,and multiple stress creep recovery tests were performed on the rubberized bitumen samples modified by the two PET-derived additives.We concluded that waste PET can be chemically upcycled into functional additives,which can increase the overall performance of the rubberized bitumen.The recycling method developed in this study not only helps alleviate the landfilling problems of both waste PET plastic and scrap tyres,but also turns these wastes into value-added new materials for building durable pavements.展开更多
The control method of rubber tyre gantry (RTG) spreader in Qingdao Port Container Terminal is logic board control,which has many shortcomings such as expensive spare parts and high faults.This paper designs a new co...The control method of rubber tyre gantry (RTG) spreader in Qingdao Port Container Terminal is logic board control,which has many shortcomings such as expensive spare parts and high faults.This paper designs a new control system using programmable logic controller (PLC) centralized control to replace the original logic board control.The new system mainly contains complete ELME spreader control scheme design,hardware selection and PLC control program development.Its field application shows that the system has characteristics of high efficiency,low running cost,easy maintenance.展开更多
A precise friction model is essential for the prediction of tyre wet grip performance and optimization of pavement surface texture design.A mechanical system for predicting the wet grip potential of asphalt pavement w...A precise friction model is essential for the prediction of tyre wet grip performance and optimization of pavement surface texture design.A mechanical system for predicting the wet grip potential of asphalt pavement was systematically presented using an extended rubber material model by a time step integration scheme.This analytical approach was transferred to a 2D numerical multi-body system consisting of interconnected masses,coupling spring and elementary rubber element of a generalized Maxwell model of rubber tyre tread.The system consists of two basic modules with the same program structure and algorithm,considering the frequency-,temperature-,and strain-dependency behaviors of the complex dynamic modulus of rubber element.The dependence of penetration depth and friction coefficient on the velocity was simulated and validated.It can be concluded that this system can be used for predicting the wet grip potential of asphalt pavements.展开更多
基金support from the Hong Kong Environment and Conservation Fund through ECF Project(84/2017)Science and Technology Project of Henan Provincial Department of Transportation(2020J6).
文摘Waste plastics,such as waste polyethylene terephthalate(PET)beverage bottles and waste rubber tyres are major municipal solid wastes,which may lead to various environmental problems if they are not appropriately recycled.In this study,the feasibility of collectively recycling the two types of waste into performance-increasing modifiers for asphalt pavements was analyzed.This study aimed to investigate the recycling mechanisms of waste PET-derived additives under the treatment of two amines,triethylenetetramine(TETA)and ethanolamine(EA),and characterize the performances of these additives in modifying rubberized bitumen,a bitumen modified by waste tyre rubber.To this end,infrared spectroscopy and thermal analyses were carried out on the two PET-derived additives(PET–TETA and PET–EA).In addition,infrared spectroscopy,viscosity,dynamic shear rheology,and multiple stress creep recovery tests were performed on the rubberized bitumen samples modified by the two PET-derived additives.We concluded that waste PET can be chemically upcycled into functional additives,which can increase the overall performance of the rubberized bitumen.The recycling method developed in this study not only helps alleviate the landfilling problems of both waste PET plastic and scrap tyres,but also turns these wastes into value-added new materials for building durable pavements.
基金Shandong University of Science and Technology Spring Buds Program(No.2010AZZ170)
文摘The control method of rubber tyre gantry (RTG) spreader in Qingdao Port Container Terminal is logic board control,which has many shortcomings such as expensive spare parts and high faults.This paper designs a new control system using programmable logic controller (PLC) centralized control to replace the original logic board control.The new system mainly contains complete ELME spreader control scheme design,hardware selection and PLC control program development.Its field application shows that the system has characteristics of high efficiency,low running cost,easy maintenance.
基金Project(FP6-PL-0506437) supported by European CommissionProject(50908053) supported by the National Natural Science Foundation of China
文摘A precise friction model is essential for the prediction of tyre wet grip performance and optimization of pavement surface texture design.A mechanical system for predicting the wet grip potential of asphalt pavement was systematically presented using an extended rubber material model by a time step integration scheme.This analytical approach was transferred to a 2D numerical multi-body system consisting of interconnected masses,coupling spring and elementary rubber element of a generalized Maxwell model of rubber tyre tread.The system consists of two basic modules with the same program structure and algorithm,considering the frequency-,temperature-,and strain-dependency behaviors of the complex dynamic modulus of rubber element.The dependence of penetration depth and friction coefficient on the velocity was simulated and validated.It can be concluded that this system can be used for predicting the wet grip potential of asphalt pavements.