泰州大桥深水沉井基础设计

泰州大桥采用主跨为1080m三塔两跨悬索桥,中塔位于主江中心。通过对沉井基础和高桩承台钻孔桩基础等多项基础方案的比选,考虑到沉井结构受力明确、刚度大、工序简单,经济性高等优点,中塔基础最终选用沉井基础。根据塔柱底的构造要求,受力要求,沉井采用58m×44m四角倒圆的矩形沉井,沉井总高76m。为了能在深水中顺利施工,沉井下部为钢壳混凝土结构,上部为钢筋混凝土结构。文中介绍了泰州大桥水中沉井的结构构造、施工方法、方案比较以及沉井的设计特点,为类似工程起到很好的借鉴作用。     

空间相关多点地震位移输入峰值控制对结构非线性响应的影响

在空间相关多点地震动人工拟合中,一般控制大跨结构不同支撑点处的地震加速度反应谱及加速度峰值相同,而相应于不同支撑点处位移时程的峰值则是不同的.为了研究地震动特性及不同的位移控制条件对结构响应的影响,引入两种不同的包线函数分别模拟地震动强度或频率非平稳特性,并且按照控制不同支撑点处时程的加速度峰值或位移峰值相同,拟合了6...     

泰州大桥中塔沉井基础承载力模型试验研究

泰州大桥中塔位于江中心,基础覆盖层高达200 m。通过多方面比选,基础采用58 m×44 m四角倒圆的矩形沉井,高76 m。为确保泰州大桥中塔沉井基础的安全和稳定,开展了1∶100的模型试验,获取了泰州大桥沉井极限承载力以及沉井埋深、土体含水量、侧壁摩阻力对极限承载力的影响。     

近场地震竖向分量对LRB基础隔震结构地震响应影响分析

该文主要对比分析了近场区竖向地震动对LRB基础结构动力响应的影响。首先,在ABAQUS有限元软件中建立了较为精确的有限元模型:上部结构采用纤维模型以考虑隔震结构在近场地震作用下可能出现的塑性变形,隔震层采用能反映隔震支座水平和竖向力学性能相互耦联的\     

近场地震竖向分量对LRB基础隔震结构地震响应影响分析EI北大核心CSCD

该文主要对比分析了近场区竖向地震动对LRB基础结构动力响应的影响。首先,在ABAQUS有限元软件中建立了较为精确的有限元模型:上部结构采用纤维模型以考虑隔震结构在近场地震作用下可能出现的塑性变形,隔震层采用能反映隔震支座水平和竖向力学性能相互耦联的"Ryan-Kelly"力学模型;同时,综合考虑隔震支座的剪切破坏和拉压破坏以确定支座的破坏界限;在此基础上,分别进行隔震结构在水平地震单独作用和水平竖向地震联合作用下的动力分析,对比分析结果可知:近场区竖向地震动对于隔震支座的破坏模式影响较大,在较大的竖向分量作用下,隔震支座可能会在剪切破坏之前先发生拉压破坏;对于上部结构的动力响应,竖向地震动的影响具有随机性,但同样不可忽略,在某些工况下,考虑竖向地震作用会较大幅度地降低其水平动力响应。     

基础提离对核电站结构地震响应的影响分析

当地震足够大时结构基础将会与下卧地基土发生分离,即所谓的基础提离现象。但该现象在常规的土-结构相互用(SSI)的地震响应分析中常常被忽视。核电站结构(NPP)由于特殊性,其设计地震强度一般较大,因而有可能发生基础提离现象。本文基于某简化核电站结构,利用大型通用软件ANSYS的接触面功能和弹簧单元,分别进行了四种工况的计算：（1）基础固定;（2）考虑基础提离,不考虑土-结构动力相互作用效应;（3）不考虑基础提离,但考虑土-结构动力相互作用效应;（4）同时考虑基础分离和土-结构动力相互作用效应。通过对比分析,确定合适的土-结构动力相互作用计算方法以及基础提离对核电站结构地震响应的影响。计算分析表明：（1）土-结构相互作用对核电站结构地震响应的影响不容忽视;（2）基础提离主要影响核电站结构竖向地震响应,而对结构水平向地震响应的影响较小。本文研究成果可为核电站结构的抗震分析提供参考。     

地震动强度指标与结构地震响应的相关性研究

目前结构抗震分析时使用的地震动强度指标较多,各种地震动强度指标的适用性尚未有统一的定论,缺乏系统的分析。采用考察结构最大地震响应与地震动强度指标之间的线性相关性的方法,选取具有代表性的100条原始地震动记录作为输入,基于不同周期的SDOF系统和实际减隔震桥梁,研究各地震动强度指标与结构地震响应的相关性。根据研究结果,将地震动强度指标划分为4类,其中以Sa(T1)为代表的第Ⅰ类强度指标与不同周期结构的相关程度都较高,而以PGA为代表的第Ⅱ类和以PGD为代表的第Ⅲ类强度指标分别对短周期和长周期结构的相关程度较高,以PGV为代表的第Ⅳ类强度指标相对较稳定,建议采用第Ⅰ类强度指标作为衡量地震动强度的指标参数。并通过工程实例进一步论证了对于自振周期已知的结构,地震动的不同强度指标与结构地震响应的相关性不同。     

结构地震响应计算模型的比较与分析

回顾并比较了地震动激励下计算结构响应的位移输入模型和一致加速度输入模型,详细地讨论了由于阻尼项忽略不同导致两种输入模型的本质差别,分析了由此对计算结果产生的影响,并通过数值算例说明该影响不容忽视,进而建议在比较地震动多点激励与一致激励下的结构反应时,一致激励应采用位移输入模型而不是一致加速度输入模型,从而可避免由于两种模型本身阻尼项忽略不同对计算结果产生的影响.此外,指出了振型叠加方法在严格理论上不适用于位移输入模型.     

地震和风效应下高耸结构振动控制模拟塔设计

介绍了地震和风效应下高耸结构振动控制模拟塔的设计方案和模拟范围，使塔的自振周期具有可调性并给出调节办法，确定了模拟地震波的施加办法及风荷载作用的模拟办法，阐述了对塔下基础、运动块（平台）和安全锁定系统的处理方法。     

TMD-基础隔震混合控制体系在近场地震作用下的能量响应与减震效果分析

基于能量平衡原理对近场地震作用下TMD-基础隔震混合控制体系进行了能量响应分析,研究了不同脉冲周期地震作用下混合控制体系的减震效果。采用Bouc-Wen模型模拟隔震层的非线性力-变形行为,建立了TMD-基础隔震混合控制体系的运动方程和相对能量平衡方程。以某八层基础隔震结构为算例,运用四阶龙格-库塔法和梯形法分别对结构安装TMD前后的非线性地震响应和能量响应进行求解,分析了混合控制体系中输入能量的变化和耗散过程。分析结果表明：以隔震层峰值位移作为控制对象时,TMD的控制效果并不好;从能量的角度来看,TMD对主结构的输入能,特别是隔震层滞回耗能的控制非常有效,这是因为TMD的阻尼耗散了体系中的大部分输入能;不同脉冲周期地震作用下TMD的减震效果差别较大,对TMD最优参数进行求解时应考虑地震动特性的影响。     

Technical research on control of caisson construction for the middle tower foundation of Taizhou Bridge

The real-time informational monitoring system is adopted in the construction of middle tower foundation of Taizhou Bridge for the first time. The geometric state of the caisson, the stress of upstream and downstream anchorage cables, underwater topography, the drag forces of the caisson cutting edge and frictional resistances of the sidewall etc. are monitored in real time. According to the synthesized data analysis and decision-making system, the spatial states of the caisson are adjusted in time to locate and embed the deep water caisson precisely. The offset errors of the caisson are less than 30cm and the vertical errors is 1/363 at the final stage. The control technology for the construction of large caisson under deep water is concluded and would be helpful to the construction of bridge foundation in the future.     

泰州大桥夹江桥动床模型试验研究

简述了泰州大桥夹江桥工程概况及在夹江桥开展动床模型试验的目的,对试验河段的水文特性及河势进行了分析,确定了模型设计的参数,在此基础上开展了建桥对河道、护岸、河床等的影响研究,为工程设计和后续实施提供了依据。     

Research on subsidence method aided by water injection and its engineering application for the north anchor of Taizhou Bridge

The north anchorage caisson of TaizhouBridge encountered some difficulties during the sinking process for the large sidewall frictional resistances. To solve this problem, a new concept and method of called subsidence method aided by water injection is proposed.Numeral analysis is adopted to simulate and the effects of this method for the north anchor of TaizhouBridge, which confirmed the feasibility and validity. Finally, the method is applied to the north anchor caisson during the caisson sinking procedure and helpsthe caisson sinkand embedto the designed position smoothly.     

Construction techniques of super length main cable of Taizhou Bridge

Taizhou Bridge is a highway three-pylon two-span bridge with span arrangement of 1 080 m + 1 080 m and the length of the main cable is more than 3 100 m. It is the longest cable in China. As the erection of the main cable needs to cross over three towers and the cables undulate acutely, general problems like the twist, spread and swell of strands and shedding of the zinc coating are prone to arise, which make it difficult to guarantee the quantity of cable traction construction. In this paper, the hauling, shaping and saddling of strands and sag adjusting are illustrated in detail and how to execute the refined construction control to guarantee the erection quality is also covered.     

泰州大桥钢箱梁除湿研究

泰州大桥主桥钢箱梁长2 160 m,体积约24万m3,采用转轮式除湿系统。阐述了泰州大桥钢箱梁除湿的原理、选型及布置、工作流程、施工等,并拟定了泰州大桥钢箱梁除湿的检验评定标准,为同类工程提供了借鉴。     

泰州大桥钢中塔线形控制误差调整方法

泰州大桥钢中塔首次采用纵向"人"字形、横向门式框架结构,采用节段预制-现场安装的方法安装钢塔。建立针对复杂钢塔的全过程施工控制体系,在制造阶段对节段形态以及制造线形进行精确测控的基础上,在安装阶段根据实际安装误差情况确定预先设置调节缝的调整量,达到对钢塔线形误差调整的目的。现场实施结果表明,泰州大桥中间钢塔的线形控制效果良好,最终线形各项精度均优于设计要求。     

Design of steel box girder for Taizhou Yangtze River Highway Bridge

Taizhou Yangtze River Highway Bridge is the first three-pylon two-span suspension bridge in China. The main girder adopts flat steamline steel closed box girder which has well wind-resistant capability and is technically mature besides beautiful appearance. Straight web plates of the steel box girder in longitudinal direction is proposed in order to ensure the integrity of the steel box girder, and to keep the stress of the steel box girder continuous in the middle pylon, as well as to reduce the gradient of the middle pylon columns . The cross section of the box girder has one box with three cells. Solid-web diaphragm plate with good integrity and high torsional stiffness is adopted. The lifting lugs are utilized in the anchors of suspender cable. In this paper, selection of the cross section of the steel box girder, the general structure design, local structure design and main structure calculation results of Taizhou Yangtze River Bridge are introduced emphatically.     

A Study of the system control model of caisson dewatering of the north anchorage of Taizhou Bridge

A caisson foundation is applied to the north anchorage of Taizhou Yangtze River Highway Bridge of which the initial caisson sinking requires dewatering. Since the caisson foundation is quite close to nearby buildings, a system control model is established with source (sink) distribution and intensity being the object function, minimum requirements of settlement and deformation of surroundings caused by dewatering and dynamic water levels during different working procedures being constraints, and the design parameter of pumping wells being the variable, as so to lower the jeopardizing of surrounding buildings, which provides a new method for active control over settlement during dewatering. Such a method of dewatering based on system control model should be of significance for similar projects involving dewatering.