为研究国内外桩基设计差异,结合伊朗德黑兰至伊斯法罕高速铁路建设,开展了中国《建筑桩基技术规范》与美国AASHTO 《Design and Construction of Driven Pile Foundations》的桩基设计区别分析,采用两种标准进行盐湖段预制桩的承载力与...为研究国内外桩基设计差异,结合伊朗德黑兰至伊斯法罕高速铁路建设,开展了中国《建筑桩基技术规范》与美国AASHTO 《Design and Construction of Driven Pile Foundations》的桩基设计区别分析,采用两种标准进行盐湖段预制桩的承载力与沉降计算。结果表明:在承载力计算方面,中国标准和AASHTO标准分别采用安全系数法与作用抗力系数法,但二者的计算原理是相同的;在沉降计算方面,中国标准和AASHTO标准均采用分层总和法,中国标准采用Boussinesq理论且沉降计算为压缩模量法,主要适应于应力历史影响小的地基沉降设计;而AASHTO标准采用应力扩散角法分析附加应力传递规律且沉降计算为e-logp曲线法,其特征在于可有效考虑地层应力历史,采用中国标准和AASHTO计算的盐湖段预制桩承载力与沉降结果差异较小,且反算桩长也基本一致。展开更多
This paper addresses a comprehensive design of RCC T-beam Bridge based on AASHTO design standards. The bridge is designed and proposed to be constructed over an irrigation canal (Zahirshahi canal) of Kandahar province...This paper addresses a comprehensive design of RCC T-beam Bridge based on AASHTO design standards. The bridge is designed and proposed to be constructed over an irrigation canal (Zahirshahi canal) of Kandahar province, Afghanistan that has more than 30 bridges over it. Yet they are not enough, and the demand for construction of new bridges is gradually arising because of the vast urbanization in the surrounding of the canal. Most of the bridges on this canal are Reinforced Concrete Slab (RCS) bridges;?these type bridges are limited by capacity and are generally found only in smaller spans. Since they can only span short distances and are often constructed as multiple-span?bridges with vertical supports between the abutments to allow a longer length.?All constructed slab bridges over Zahirshahi canal are four-span bridges. Constructing multi-span bridges on the canal decreases waterway due to the existence of many piers and footings that could increase the water level during the peak flow, even, sometimes can cause over flow. Taking into consideration these deficiencies of the present (RCS) bridges, two-span RCC T-beam Bridge is one of the best alternatives to be constructed over the canal. In addition, canal cross-sectional dimensions are almost constant along its length, though the construction of two-span RCC T-beam bridge is applicable at any point of the canal. The design is selected based on exclusive survey of the area during all seasons including the peak flowing of the canal.展开更多
文摘为研究国内外桩基设计差异,结合伊朗德黑兰至伊斯法罕高速铁路建设,开展了中国《建筑桩基技术规范》与美国AASHTO 《Design and Construction of Driven Pile Foundations》的桩基设计区别分析,采用两种标准进行盐湖段预制桩的承载力与沉降计算。结果表明:在承载力计算方面,中国标准和AASHTO标准分别采用安全系数法与作用抗力系数法,但二者的计算原理是相同的;在沉降计算方面,中国标准和AASHTO标准均采用分层总和法,中国标准采用Boussinesq理论且沉降计算为压缩模量法,主要适应于应力历史影响小的地基沉降设计;而AASHTO标准采用应力扩散角法分析附加应力传递规律且沉降计算为e-logp曲线法,其特征在于可有效考虑地层应力历史,采用中国标准和AASHTO计算的盐湖段预制桩承载力与沉降结果差异较小,且反算桩长也基本一致。
文摘This paper addresses a comprehensive design of RCC T-beam Bridge based on AASHTO design standards. The bridge is designed and proposed to be constructed over an irrigation canal (Zahirshahi canal) of Kandahar province, Afghanistan that has more than 30 bridges over it. Yet they are not enough, and the demand for construction of new bridges is gradually arising because of the vast urbanization in the surrounding of the canal. Most of the bridges on this canal are Reinforced Concrete Slab (RCS) bridges;?these type bridges are limited by capacity and are generally found only in smaller spans. Since they can only span short distances and are often constructed as multiple-span?bridges with vertical supports between the abutments to allow a longer length.?All constructed slab bridges over Zahirshahi canal are four-span bridges. Constructing multi-span bridges on the canal decreases waterway due to the existence of many piers and footings that could increase the water level during the peak flow, even, sometimes can cause over flow. Taking into consideration these deficiencies of the present (RCS) bridges, two-span RCC T-beam Bridge is one of the best alternatives to be constructed over the canal. In addition, canal cross-sectional dimensions are almost constant along its length, though the construction of two-span RCC T-beam bridge is applicable at any point of the canal. The design is selected based on exclusive survey of the area during all seasons including the peak flowing of the canal.