Along with the popularization and application of the steel bridge in China,due to the high modulus of asphalt concrete with good waterproof,anti-fatigue,anti-aging and good performance,asphalt concrete with high modul...Along with the popularization and application of the steel bridge in China,due to the high modulus of asphalt concrete with good waterproof,anti-fatigue,anti-aging and good performance,asphalt concrete with high modulus was widely used in steel bridge deck pavement,the test and comparative study of high modulus asphalt concrete were carried out based on two types of common high modulus asphalt concrete which include the casting type asphalt concrete and epoxy resin modified asphalt concrete,aims to further explore the performance features of the steel bridge deck with high modulus asphalt concrete,and provide help on the application of this asphalt concrete on the steel bridge deck.展开更多
As a solution against the serviceability problem caused by the cracks occurring at the UHPC precast deck-joint interface, this study proposes a method exposing the steel fiber at the interface and evaluates the corres...As a solution against the serviceability problem caused by the cracks occurring at the UHPC precast deck-joint interface, this study proposes a method exposing the steel fiber at the interface and evaluates the corresponding flexural performance of the lap spliced construction joint. After having slowed down the strength development of the concrete placed in the joint of the precast deck by means of a curing retardant, the concrete at the interface is crushed so as to expose the steel fibers and the change in the flexural performance is observed experimentally according to the exposure of the steel fibers. The results show that, even if the ultimate strength and stiffness of the UHPC precast deck including the joint are mostly determined by the arrangement details of the rebar lap splice, the exposure of the steel fibers can secure stable ductile behavior and reduce the width of the cracks generated at the precast deck-joint interface under service load.展开更多
This research investigated a pavement system on steel bridge decks that use epoxy resin(EP)bonded ultra-high performance concrete(UHPC).Through FEM analysis and static and dynamic bending fatigue tests of the composit...This research investigated a pavement system on steel bridge decks that use epoxy resin(EP)bonded ultra-high performance concrete(UHPC).Through FEM analysis and static and dynamic bending fatigue tests of the composite structure,the influences of the interface of the pavement layer,reinforcement,and different paving materials on the structural performance were compared and analyzed.The results show that the resin bonded UHPC pavement structure can reduce the weld strain in the steel plate by about 32%and the relative deflection between ribs by about 52%under standard axial load conditions compared to traditional pavements.The EP bonding layer can nearly double the drawing strength of the pavement interface from 1.3 MPa,and improve the bending resistance of the UHPC structure on steel bridge decks by about 50%;the bending resistance of reinforced UHPC structures is twice that of unreinforced UHPC structure,and the dynamic deflection of the UHPC pavement structure increases exponentially with increasing fatigue load.The fatigue life is about 1.2×10^(7) cycles under a fixed force of 9 kN and a dynamic deflection of 0.35 mm,which meets the requirements for fatigue performance of pavements on steel bridge decks under traffic conditions of large flow and heavy load.展开更多
Ultra-high performance concrete (UHPC) is featured by a compressive strength 5 times higher than that of ordinary concrete and by a high durability owing to the control of the chloride penetration speed by its dense s...Ultra-high performance concrete (UHPC) is featured by a compressive strength 5 times higher than that of ordinary concrete and by a high durability owing to the control of the chloride penetration speed by its dense structure. The high strength characteristics of UHPC offer numerous advantages like the reduction of the quantities of cables and foundations by the design of a lightweight superstructure in the case of the long-span bridge preserving its structural performance through axial forces and structures governed by compression. This study conducted the conceptual design of a hybrid cable-stayed bridge with central span of 1000 m and exploiting 200 MPa-class UHPC. The economic efficiency of the conceptual design results of the hybrid cable-stayed bridge with central span of 1000 m and of Sutong Bridge, the longest cable-stayed bridge in the world, was analyzed.展开更多
近年来,超高性能混凝土(UHPC)得到了推广应用,但在UHPC生产过程中超量水泥消耗以及UHPC自身耐久性强、寿命长的特点,对UHPC的碳排放水平认识尚不清楚。因此,研究采用生命周期评价(LCA)方法构建了UHPC碳排放定量分析模型,对比分析钢-UHP...近年来,超高性能混凝土(UHPC)得到了推广应用,但在UHPC生产过程中超量水泥消耗以及UHPC自身耐久性强、寿命长的特点,对UHPC的碳排放水平认识尚不清楚。因此,研究采用生命周期评价(LCA)方法构建了UHPC碳排放定量分析模型,对比分析钢-UHPC桥面板与常规钢-混桥面板结构在全生命周期内的碳排放。结果表明:虽然生产阶段UHPC的碳排放量约1 245.84 kg CO_(2)eq/m^(3),是普通混凝土的1.58倍,但从性能上来说,UHPC碳强度是普通混凝土的62.25%,是一种更绿色的建材;在整个生命周期内,与常规钢-混桥面板相比,钢-UHPC桥面板的年均碳排放量下降了35.76%,具有巨大的碳减排潜力,有助于基础设施的可持续性发展;钢-UHPC桥面板方案具有工程比选优势,经济性合理,同时其单位产值碳排放为0.89 t CO_(2)eq/万元,是常规钢-混桥面板的86.41%,具有更好的减碳效果。研究对结果的可靠性和碳减排措施进行了讨论,最后提出了有待进一步研究的内容。展开更多
文摘Along with the popularization and application of the steel bridge in China,due to the high modulus of asphalt concrete with good waterproof,anti-fatigue,anti-aging and good performance,asphalt concrete with high modulus was widely used in steel bridge deck pavement,the test and comparative study of high modulus asphalt concrete were carried out based on two types of common high modulus asphalt concrete which include the casting type asphalt concrete and epoxy resin modified asphalt concrete,aims to further explore the performance features of the steel bridge deck with high modulus asphalt concrete,and provide help on the application of this asphalt concrete on the steel bridge deck.
文摘As a solution against the serviceability problem caused by the cracks occurring at the UHPC precast deck-joint interface, this study proposes a method exposing the steel fiber at the interface and evaluates the corresponding flexural performance of the lap spliced construction joint. After having slowed down the strength development of the concrete placed in the joint of the precast deck by means of a curing retardant, the concrete at the interface is crushed so as to expose the steel fibers and the change in the flexural performance is observed experimentally according to the exposure of the steel fibers. The results show that, even if the ultimate strength and stiffness of the UHPC precast deck including the joint are mostly determined by the arrangement details of the rebar lap splice, the exposure of the steel fibers can secure stable ductile behavior and reduce the width of the cracks generated at the precast deck-joint interface under service load.
基金This work is jointly supported by the Natural Science Foundation of Jiangsu Province(Nos.BK20180113 and BK20181112)the Jiangsu Provincial Programme for High-Level Talents in Six Areas(No.XCL-CXTD-007)+1 种基金the Youth Programme of National Natural Science Foundation of China(Grant No.51908285)the Transformation Project of Scientific and Technological Achievements of Qinghai Province(No.2017-SF-134).
文摘This research investigated a pavement system on steel bridge decks that use epoxy resin(EP)bonded ultra-high performance concrete(UHPC).Through FEM analysis and static and dynamic bending fatigue tests of the composite structure,the influences of the interface of the pavement layer,reinforcement,and different paving materials on the structural performance were compared and analyzed.The results show that the resin bonded UHPC pavement structure can reduce the weld strain in the steel plate by about 32%and the relative deflection between ribs by about 52%under standard axial load conditions compared to traditional pavements.The EP bonding layer can nearly double the drawing strength of the pavement interface from 1.3 MPa,and improve the bending resistance of the UHPC structure on steel bridge decks by about 50%;the bending resistance of reinforced UHPC structures is twice that of unreinforced UHPC structure,and the dynamic deflection of the UHPC pavement structure increases exponentially with increasing fatigue load.The fatigue life is about 1.2×10^(7) cycles under a fixed force of 9 kN and a dynamic deflection of 0.35 mm,which meets the requirements for fatigue performance of pavements on steel bridge decks under traffic conditions of large flow and heavy load.
文摘Ultra-high performance concrete (UHPC) is featured by a compressive strength 5 times higher than that of ordinary concrete and by a high durability owing to the control of the chloride penetration speed by its dense structure. The high strength characteristics of UHPC offer numerous advantages like the reduction of the quantities of cables and foundations by the design of a lightweight superstructure in the case of the long-span bridge preserving its structural performance through axial forces and structures governed by compression. This study conducted the conceptual design of a hybrid cable-stayed bridge with central span of 1000 m and exploiting 200 MPa-class UHPC. The economic efficiency of the conceptual design results of the hybrid cable-stayed bridge with central span of 1000 m and of Sutong Bridge, the longest cable-stayed bridge in the world, was analyzed.
文摘近年来,超高性能混凝土(UHPC)得到了推广应用,但在UHPC生产过程中超量水泥消耗以及UHPC自身耐久性强、寿命长的特点,对UHPC的碳排放水平认识尚不清楚。因此,研究采用生命周期评价(LCA)方法构建了UHPC碳排放定量分析模型,对比分析钢-UHPC桥面板与常规钢-混桥面板结构在全生命周期内的碳排放。结果表明:虽然生产阶段UHPC的碳排放量约1 245.84 kg CO_(2)eq/m^(3),是普通混凝土的1.58倍,但从性能上来说,UHPC碳强度是普通混凝土的62.25%,是一种更绿色的建材;在整个生命周期内,与常规钢-混桥面板相比,钢-UHPC桥面板的年均碳排放量下降了35.76%,具有巨大的碳减排潜力,有助于基础设施的可持续性发展;钢-UHPC桥面板方案具有工程比选优势,经济性合理,同时其单位产值碳排放为0.89 t CO_(2)eq/万元,是常规钢-混桥面板的86.41%,具有更好的减碳效果。研究对结果的可靠性和碳减排措施进行了讨论,最后提出了有待进一步研究的内容。
