Rubblization technique has been extensively used to repair the damaged concrete pavement and has proven successful in developed countries like the US and Europe. It has not been fully adopted in developing region like...Rubblization technique has been extensively used to repair the damaged concrete pavement and has proven successful in developed countries like the US and Europe. It has not been fully adopted in developing region like the Middle East and this paper presents the design and construction challenges posed while assessing damaged concrete runway in empty quarter of Saudi Arabia. <span style="font-family:Verdana;">A number of design options for repairs for runway pavement were consi</span><span style="font-family:Verdana;">dered and rubblization was chosen as a preferred option for repair. This paper includes the consideration for the assessment and adoption of the concrete rubblized modulus value using the falling weight deflectometer, optimization </span><span style="font-family:Verdana;">of the tests for the whole runway using the Heavy Weight Deflectometer</span><span style="font-family:Verdana;"> HWD testing to replace pits, safely working around the utilities, reasonable assumption of drop height of the pavement and installation of utility conduits in the rubblized layer. Findings of the paper demonstrates resolving</span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">technical issues which are not very well covered in the Federal Aviation Authority (FAA) EB-66 such as the additional test strips, minimum areas of rubblization for assessment using test pits, drop in the height of concrete surface and fixing of utilities in rubblized pavement. The case study demonstrates that the rubblization can be successfully carried out in remote locations like empty quarter of Saudi Arabia with carefully carried out detailed site investigations, adopt</span><span style="font-family:Verdana;">ing correct assumed design rubblization modulus, quality control using </span><span style="font-family:Verdana;">HWD, protection of utilities while rubblizing and use of polymer modified asphalt for successful project deployment.</span></span></span></span>展开更多
The corrosion of the anticorrosion coating and the defects of the asphalt concrete paved layer have been investigated on long-span steel box bridge decks. The anticorrosion coating lies in the midclle of two entirely ...The corrosion of the anticorrosion coating and the defects of the asphalt concrete paved layer have been investigated on long-span steel box bridge decks. The anticorrosion coating lies in the midclle of two entirely different materials： a highway steel box bridge deck and a paved layer, which is used as anticorrosion and waterproof coating for the steel bridge deck. For our study, electrochemical corrosion and pull strength experiments have been selected for the investigation of the corrosion properties of inorganic zinc rich coating, epoxy zinc rich coating and arc sprayed zinc coating. The adhesive strength between the coatings and the panel, and the effect of the coating corrosion on the shear properties of the paved layers including cast asphalt, thermal asphalt mortar, epoxy asphalt and modified asphalt con- crete have been investigated. The results show that the adhesive strength between the coatings and the bridge panel is controlled by the method of pre-processing rust removal. Coating by sandblasting has stronger adhesive strength than coating by shot peening. The results also reveal that shear strength of the paved layer is affected by the corrosion product of zinc coating. The arc sprayed zinc coating has stronger shear strength than zinc rich coatings.展开更多
With the continuous development of bridge and tunnel construction technologies,large-scale sea-crossing bridges and tunnels have gradually become the preferred choice for regional traffic.The construction technology o...With the continuous development of bridge and tunnel construction technologies,large-scale sea-crossing bridges and tunnels have gradually become the preferred choice for regional traffic.The construction technology of Hong Kong-Zhuhai-Macao Bridge(HZMB),one of the most representative sea-crossing passageways,is instructive for the construction of other large sea-crossing infrastructures.At present,the pavement design method of sea-crossing passageways lacks pertinence as it still refers to specifications for design of common pavement.Therefore,it is necessary to consider the bridge and tunnel pavement of HZMB as a typical example to analyze key technical problems encountered in its design,construction and operation.Novel solutions for material selection and structural design built upon the analysis of such critical problems should thus follow up.Based on comprehensive literature research,it can be found that environmental variability,tunnel closure,structural differential settlement and expansion deformation are the key technical problems faced by pavement of sea-crossing passageways.In view of the environmental variability,the steel deck-paving material and structure design of GMA-10 t SMA-13 is innovatively proposed.As for the closure of immersed tube tunnel,warm-mix flame retardant asphalt mixture is used to control pavement design through key indexes such as temperature and limit oxygen index.Regarding the deformation of immersed pipe joints,BJ200 asphalt seamless expansion joint material is introduced,which effectively satisfies the multi-directional deformation between pipe joints and ensures the smoothness of the road surface and driving comfort.For segmental joints,double-layer waterproof-coiled material is used to effectively prevent reflective cracks while ensuring the continuity of asphalt concrete pavement.Therefore,this paper provides a panel of ideas and methods for the pavement design of the same type of sea-crossing passageways.展开更多
The volume of e-commerce trade is surging, mobile payment is taking over the world, and the sharing economy is a worldwide phenomenon. In recent years, China has made remarkable achievements in the digital economy dom...The volume of e-commerce trade is surging, mobile payment is taking over the world, and the sharing economy is a worldwide phenomenon. In recent years, China has made remarkable achievements in the digital economy domain, which has garnered attention from a wide range of sources.展开更多
The stability of roads in cities directly affects the safety of traffic and transportation.In the process of pavement laying,relevant personnel should use permeable paving materials in the process of construction.Base...The stability of roads in cities directly affects the safety of traffic and transportation.In the process of pavement laying,relevant personnel should use permeable paving materials in the process of construction.Based on the analysis of road drainage requirements,traditional paving materials have relatively poor water permeability,which leads to ponding problems during road use[1].Within this frame of reference,beginning with the characteristics of permeable paving materials,this paper makes an in-depth exploration on practical application measures.展开更多
Hardly had the elation in the wake of the 1,200 km-survival of quantum entanglement subsided before we again had news from Micius.On August 10,the joint team reported online in Nature the results from the other two ma...Hardly had the elation in the wake of the 1,200 km-survival of quantum entanglement subsided before we again had news from Micius.On August 10,the joint team reported online in Nature the results from the other two major experiments aboard the satellite:Both the encrypted quantum key distribution(QKD)and quantum teleportation(QT)successfully passed through a distance of approximately 1,200 km,and did so less展开更多
China TieTong has made great achievements since it was founded about six years ago. And the achievements made by China TieTong cannot be separated from the path of differentiation it has stuck to. Zhao Jibin, board ch...China TieTong has made great achievements since it was founded about six years ago. And the achievements made by China TieTong cannot be separated from the path of differentiation it has stuck to. Zhao Jibin, board chairman of China TieTong has pointed out the company should develop a path of "enlarging the dedicated network and strengthening the regional service" to ensure precise positioning and successful implementation of the development strategy with solid management foundation and improving managem...展开更多
2000 years ago, Silk Road was considered the concernful channel of trade promotion that connects China and the world, stretching thousands of miles running through the desert. At that time, groups of Chinese traders c...2000 years ago, Silk Road was considered the concernful channel of trade promotion that connects China and the world, stretching thousands of miles running through the desert. At that time, groups of Chinese traders crossed this road with the help of camels at the risk oflosing their own life in the desert; venturing their trade in westerncountries. Nowadays, sands have covered this road and soundfrom camel bells has died out for a long time, but the pioneeringspirit of Chinese trade forerunners has been passed to us despitethe lapse of time. As a trade platform of China’s textile and apparelenterprises, the Sub-Council of Textile Industry, China Council forthe Promotion of International Trade (CCPIT TEX) was consideredas an intangible Silk Road that provides trade opportunitiesthrough organizing expo. and exhibitions.展开更多
The improvement of road surface engineering construction quality is helpful to create safe and comfortable travel conditions for people and prevent traffic accidents. With the acceleration of highway construction in o...The improvement of road surface engineering construction quality is helpful to create safe and comfortable travel conditions for people and prevent traffic accidents. With the acceleration of highway construction in our country, the standard of pavement construction is also improving. Only by strictly following the national and industry standards can the service life of the pavement be prolonged and the subsequent maintenance and management work be guaranteed. Especially in asphalt paving, temperature, humidity and geological conditions will have different degrees of influence, which brings great difficulty to the construction. Performance parameters such as compactness and cohesiveness of asphalt mixture also determine the overall paving quality. In the construction, the effect of various factors should be considered, and a practical construction organization scheme should be prepared according to the construction requirements and actual conditions of highway pavement engineering. In addition, ensure that the paving technology meets the standard requirements, strengthen the construction standardization and reduce the probability of pavement diseases.展开更多
From lecture halls in Beijing to villages in the mountains of southwest China,a group of young rural innovators from Global South countries recently embarked on a journey that connected policy thinking,technological p...From lecture halls in Beijing to villages in the mountains of southwest China,a group of young rural innovators from Global South countries recently embarked on a journey that connected policy thinking,technological practice and lived rural experience.展开更多
文摘Rubblization technique has been extensively used to repair the damaged concrete pavement and has proven successful in developed countries like the US and Europe. It has not been fully adopted in developing region like the Middle East and this paper presents the design and construction challenges posed while assessing damaged concrete runway in empty quarter of Saudi Arabia. <span style="font-family:Verdana;">A number of design options for repairs for runway pavement were consi</span><span style="font-family:Verdana;">dered and rubblization was chosen as a preferred option for repair. This paper includes the consideration for the assessment and adoption of the concrete rubblized modulus value using the falling weight deflectometer, optimization </span><span style="font-family:Verdana;">of the tests for the whole runway using the Heavy Weight Deflectometer</span><span style="font-family:Verdana;"> HWD testing to replace pits, safely working around the utilities, reasonable assumption of drop height of the pavement and installation of utility conduits in the rubblized layer. Findings of the paper demonstrates resolving</span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">technical issues which are not very well covered in the Federal Aviation Authority (FAA) EB-66 such as the additional test strips, minimum areas of rubblization for assessment using test pits, drop in the height of concrete surface and fixing of utilities in rubblized pavement. The case study demonstrates that the rubblization can be successfully carried out in remote locations like empty quarter of Saudi Arabia with carefully carried out detailed site investigations, adopt</span><span style="font-family:Verdana;">ing correct assumed design rubblization modulus, quality control using </span><span style="font-family:Verdana;">HWD, protection of utilities while rubblizing and use of polymer modified asphalt for successful project deployment.</span></span></span></span>
基金Project BK2005020 supported by the Natural Science Foundation of the Jiangsu Province
文摘The corrosion of the anticorrosion coating and the defects of the asphalt concrete paved layer have been investigated on long-span steel box bridge decks. The anticorrosion coating lies in the midclle of two entirely different materials： a highway steel box bridge deck and a paved layer, which is used as anticorrosion and waterproof coating for the steel bridge deck. For our study, electrochemical corrosion and pull strength experiments have been selected for the investigation of the corrosion properties of inorganic zinc rich coating, epoxy zinc rich coating and arc sprayed zinc coating. The adhesive strength between the coatings and the panel, and the effect of the coating corrosion on the shear properties of the paved layers including cast asphalt, thermal asphalt mortar, epoxy asphalt and modified asphalt con- crete have been investigated. The results show that the adhesive strength between the coatings and the bridge panel is controlled by the method of pre-processing rust removal. Coating by sandblasting has stronger adhesive strength than coating by shot peening. The results also reveal that shear strength of the paved layer is affected by the corrosion product of zinc coating. The arc sprayed zinc coating has stronger shear strength than zinc rich coatings.
基金This paper was financially supported by the National Natural Science Foundation of China(52038001,52122809).
文摘With the continuous development of bridge and tunnel construction technologies,large-scale sea-crossing bridges and tunnels have gradually become the preferred choice for regional traffic.The construction technology of Hong Kong-Zhuhai-Macao Bridge(HZMB),one of the most representative sea-crossing passageways,is instructive for the construction of other large sea-crossing infrastructures.At present,the pavement design method of sea-crossing passageways lacks pertinence as it still refers to specifications for design of common pavement.Therefore,it is necessary to consider the bridge and tunnel pavement of HZMB as a typical example to analyze key technical problems encountered in its design,construction and operation.Novel solutions for material selection and structural design built upon the analysis of such critical problems should thus follow up.Based on comprehensive literature research,it can be found that environmental variability,tunnel closure,structural differential settlement and expansion deformation are the key technical problems faced by pavement of sea-crossing passageways.In view of the environmental variability,the steel deck-paving material and structure design of GMA-10 t SMA-13 is innovatively proposed.As for the closure of immersed tube tunnel,warm-mix flame retardant asphalt mixture is used to control pavement design through key indexes such as temperature and limit oxygen index.Regarding the deformation of immersed pipe joints,BJ200 asphalt seamless expansion joint material is introduced,which effectively satisfies the multi-directional deformation between pipe joints and ensures the smoothness of the road surface and driving comfort.For segmental joints,double-layer waterproof-coiled material is used to effectively prevent reflective cracks while ensuring the continuity of asphalt concrete pavement.Therefore,this paper provides a panel of ideas and methods for the pavement design of the same type of sea-crossing passageways.
文摘The volume of e-commerce trade is surging, mobile payment is taking over the world, and the sharing economy is a worldwide phenomenon. In recent years, China has made remarkable achievements in the digital economy domain, which has garnered attention from a wide range of sources.
文摘The stability of roads in cities directly affects the safety of traffic and transportation.In the process of pavement laying,relevant personnel should use permeable paving materials in the process of construction.Based on the analysis of road drainage requirements,traditional paving materials have relatively poor water permeability,which leads to ponding problems during road use[1].Within this frame of reference,beginning with the characteristics of permeable paving materials,this paper makes an in-depth exploration on practical application measures.
文摘Hardly had the elation in the wake of the 1,200 km-survival of quantum entanglement subsided before we again had news from Micius.On August 10,the joint team reported online in Nature the results from the other two major experiments aboard the satellite:Both the encrypted quantum key distribution(QKD)and quantum teleportation(QT)successfully passed through a distance of approximately 1,200 km,and did so less
文摘China TieTong has made great achievements since it was founded about six years ago. And the achievements made by China TieTong cannot be separated from the path of differentiation it has stuck to. Zhao Jibin, board chairman of China TieTong has pointed out the company should develop a path of "enlarging the dedicated network and strengthening the regional service" to ensure precise positioning and successful implementation of the development strategy with solid management foundation and improving managem...
文摘2000 years ago, Silk Road was considered the concernful channel of trade promotion that connects China and the world, stretching thousands of miles running through the desert. At that time, groups of Chinese traders crossed this road with the help of camels at the risk oflosing their own life in the desert; venturing their trade in westerncountries. Nowadays, sands have covered this road and soundfrom camel bells has died out for a long time, but the pioneeringspirit of Chinese trade forerunners has been passed to us despitethe lapse of time. As a trade platform of China’s textile and apparelenterprises, the Sub-Council of Textile Industry, China Council forthe Promotion of International Trade (CCPIT TEX) was consideredas an intangible Silk Road that provides trade opportunitiesthrough organizing expo. and exhibitions.
文摘The improvement of road surface engineering construction quality is helpful to create safe and comfortable travel conditions for people and prevent traffic accidents. With the acceleration of highway construction in our country, the standard of pavement construction is also improving. Only by strictly following the national and industry standards can the service life of the pavement be prolonged and the subsequent maintenance and management work be guaranteed. Especially in asphalt paving, temperature, humidity and geological conditions will have different degrees of influence, which brings great difficulty to the construction. Performance parameters such as compactness and cohesiveness of asphalt mixture also determine the overall paving quality. In the construction, the effect of various factors should be considered, and a practical construction organization scheme should be prepared according to the construction requirements and actual conditions of highway pavement engineering. In addition, ensure that the paving technology meets the standard requirements, strengthen the construction standardization and reduce the probability of pavement diseases.
文摘From lecture halls in Beijing to villages in the mountains of southwest China,a group of young rural innovators from Global South countries recently embarked on a journey that connected policy thinking,technological practice and lived rural experience.
