2007年4月摘要 大跨屋盖结构风压脉动的非高斯特性孙 瑛1 武 岳1，2 林志兴2 沈世钊1 摘要：借助刚性模型风洞动态同步测压试验，对大跨度平屋盖表面脉动风压的非高斯统计特性进行了系统研究。首先，根据测点风压时程及其概率密度分布，对具有非高斯分布特性的屋盖风压局部区域做出判断；然后，通过风压的时空间相关性，结合中心极限定理讨论局部呈现非高斯特性的原因；最后，基于测点风压的第三、四阶矩统计量对风压的非高斯特性进行描述，给出划分高斯非高斯区域的标准，并在此基础上对平屋盖进行了分区，通过区域划分揭示了不同区域的脉动风压形成机理，也体现出一些大跨屋盖结构不同于低矮房屋的流场特性。通过上述工作，增进了对大跨度屋盖表面风压分布特性的认识，为进一步探讨屋盖结构的抗风设计方法奠定了理论基础。 Non-Gaussian features of fluctuating wind pressures on long span roofsSun Ying1 Wu Yue1,2 Lin Zhixing2 Shen Shizhao1 Abstract: The non-Gaussian features of fluctuating wind pressures on long span roofs are systematically studied by using multi-channel measurement wind tunnel tests. Wind pressure sample time series and histograms are employed to identify the local regions in which the wind pressure fluctuations exhibit clear non-Gaussian nature. The cause for non-Gaussian features in separated regions is discussed by combining the analysis of spatial correlation of wind pressures and the central limit theorem. The third and fourth order statistical moments of fluctuating wind pressures are employed to obtain a description and measurement of the non-Gaussian feature, and to locate regions with non-Gaussian features in long span flat roofs. Different wind fluctuating mechanisms, exhibiting different flow characteristics between long-span roofs and low-rise buildings, may be revealed from the division of roof regions. E-mail: sunnyhit@sina.com 混凝土二维本构关系试验研究李 杰 任晓丹 杨卫忠 摘要: 本文采用Instron-8506四立柱液压伺服试验机对混凝土二维本构关系进行了系统的试验研究。在应变控制加载的条件下测得了混凝土板式试件在二轴压-压区和拉-压区的双轴应力应变全曲线。分析了试件的破坏特点，讨论了不同应变组合条件下试件的破坏模式。提取全曲线的特征参数，建立了应力空间和应变空间的强度包络线，并与经典试验结果进行了对比。研究表明双轴应变比例控制加载条件下可以测得混凝土板式试件的二轴应力应变全曲线，所得曲线具有一定的精度和可信性。本文得到的应力应变全曲线和包络线为多轴本构关系的研究以及复杂结构设计提供了依据。 Experimental study on 2-D constitutive relationship for concreteLi Jie Ren Xiaodan Yang Weizhong Abstract: Systematic experimental studies were carried out on an Instron-8506 hydraulic servo test machine to investigate the 2-D constitutive law for plain concrete. Biaxial stress-strain curves of biaxial compression and compression-tension were obtained under biaxial strain-controlled loading condition. Based on observations of specimens, failure modes in different loading combinations were discussed. The ultimate strength envelopes in both stress space and strain space were developed by analysis of the experimental data and compared with the results of some classical experiments. It is concluded that biaxial full process strain-stress curves of concrete specimen can be obtained under biaxial proportional strain-controlled loading condition. This study laid a solid foundation for the further research on multi-axial constitutive laws of concrete. E-mail: lijie@tongji.edu.cn 基于结构设计的基础隔震结构高宽比限值的研究祁 皑 范宏伟 摘要：本文研究了橡胶支座基础隔震结构的高宽比限值。研究基于保证隔震结构在强震中不倾覆的两个充分条件，一个是橡胶隔震支座不能产生拉应力，另一个是隔震支座压应力不超过容许值。本文推导了隔震结构高宽比限值的显式并给出了针对不同建筑类别、不同设防烈度、不同场地条件和不同隔震层阻尼比的高宽比限值。在支座的轴力计算中，还考虑了竖向地震作用和荷载的最不利组合。研究发现，当控制条件为支座不产生拉应力时，高宽比限值随隔震结构周期的增加而增加；当控制条件为支座压应力不超过容许值时，高宽比限值随隔震结构周期的增加而减小。因此，存在一个临界周期使高宽比限值取得极大值。研究还发现，存在一个最大的隔震结构周期使高宽比限值等于零或隔震层位移超过容许值。将隔震结构的周期与临界周期和最大隔震周期比较，就可以得到相应高宽比限值的表达式。最后，按照简单、安全的原则，将各种工况下的高宽比限值进行了归并，给出了高宽比限值的设计建议值。同时，还按设计规范提供的结构周期计算公式计算了隔震结构的高度限值。 A structural design study on the limit of height-width ratio of base-isolated structuresQi Ai Fan Hongwei Abstract:The limit of height-width ratio of base-isolated structure with rubber bearings is investigated. Two sufficient conditions that could keep the base-isolated structure from overturning during strong earthquake are considered. One is that rubber bearings should not be subjected to tensile stress, and the other is that the compressive stress in rubber bearings should not exceed the allowable value. The derivation of limit ratio formulas are performed and the results are presented corresponding to different building categories, earthquake fortification intensities, site classifications, and damping ratios of isolated story. In the formulas for the axial force in rubber bearings, vertical seismic action and the most unfavorable load combinations are considered. It is found that, the limit ratio increases with the isolation period when it is confined by the first sufficient condition, and decreases when confined by the second one. So there exists a critical period, at which, the limit ratio reaches its maximum value. It is also found that there exists a maximum isolation period, at which, the limit ratio is zero or the horizontal displacement of the rubber bearing exceeds the allowable value. By comparing the isolation period with the critical and maximum periods, the limit ratio can be obtained by using the corresponding formulas. In conformity to the principle of simplicity and safety, the calculated limit ratios were summarized to obtain the suggested values. The limit height of base-isolated structures are also calculated by using the period formulas of non-isolated structures as suggested in the design code. E-mail: qikai@fzu.edu.cn 纵向焊接铝合金柱设计方法研究吴 芸 张其林 摘要：大多数结构用铝合金通常要经过热处理或加工硬化以得到比退火状态更高的力学性能。这种合金焊接后，焊接热会使焊缝附近局部区域（称为热影响区HAZ）强度降低。而对于钢结构，由于其热导率比铝材小得多，因此只有高强钢才可能产生强度降低的热影响区，而且其强度的降低没有铝合金显著，热影响区宽度也比铝合金小得多。这将使焊接铝合金柱的设计变得更为复杂。由于我国目前还没有关于铝合金结构的设计规范，为此本文通过试验研究及对已有试验数据的分析，并参考国外规范，提出了纵向焊接铝合金柱设计方法的建议，并将计算结果与试验结果进行比较，两者吻合较好，从而验证了建议设计公式的适用性。 A study on the design method for aluminum columns with longitudinal weldsWu Yun Zhang Qilin Abstract: Most aluminum alloys employed in structures are either heat-treated or cold-hardened in order to develop higher mechanical properties than those in the annealed state. When alloys with enhanced properties are welded, its strength will be reduced due to the welding heat in a region adjacent to the welds, called the Heat Affected Zone (HAZ). Because the heat exchange ratio of steel is much lower than that of aluminum alloys, HAZ only occurs for high strength steels with much smaller width and strength reduction. This makes the design of welded aluminum columns much more complicated than the design of a welded steel column. Up to now, there is still no code for aluminum structures in China. Tests were carried out, and analyses of the existing experimental results conducted, based on which and by referring to the foreign codes, suggestions for the design of longitudinally welded aluminum columns are proposed. The design results are in good agreement with the test results, indicating that the proposed design method is practical. E-mail: wuyun360@163.com 不同受火方式下混凝土柱耐火性能的试验研究吴 波1 唐贵和2 王 超1 摘要：进行6组共18个圆钢管约束高强混凝土短柱在循环或单调轴压荷载作用下的试验研究。试验中的主要参数为混凝土强度（fcu=88.14~94.17）和钢管径厚比（D/t=21.62~43.01）。试验结果表明，圆钢管约束高强混凝土短柱的轴压承载力高于同条件的普通钢管混凝土构件，但两种构件的延性无显著差异；随钢管中纵向应力的降低，构件的轴压承载力提高。对构件的应力分析结果表明，圆钢管约束高强混凝土轴压短柱的峰值荷载点对应于钢管的屈服点。在应力分析结果的基础上建立圆钢管约束混凝土的轴压承载力公式，公式结果与试验结果吻合较好。基于试验结果对Mander约束混凝土模型进行修正，使模型适合于约束高强混凝土。 Experimental study on fire resistance of RC columns with different faces exposed to fireWu Bo1 Tang Guihe2 Wang Chao1 Abstract: Five full-scale high strength concrete(HSC)columns and two full-scale normal strength concrete(NSC)columns were tested for fire resistance. The effect of different types of fire exposure on the failure mode, axial deformation and fire resistance of the columns was investigated. The results indicate that：(1) columns with four faces not all subjected to fire exhibit stronger fire resistance than columns with all four faces in fire, whereas the fire resistance of three-face-under-fire columns is less than that of two-face-under-fire columns；(2) the fire resistance of HSC columns is much less than that of NSC columns with same axial load ratio and same fire exposure；(3) the fire resistance of NSC columns with high axial load ratio may be less than that of HSC columns with moderate axial load ratio. In fire-resistant structure design, it is necessary to reasonably consider the effect of fire exposures, concrete strength and axial load ratio on the fire resistance of RC columns. E-mail: bowu@scut.edu.cn 特大跨径悬索桥上部结构施工关键技术研究吴胜东 冯兆祥 蒋 波 摘要：介绍了目前位居“中国第一、世界第三”的润扬大桥悬索桥上部结构施工中无抗风缆猫道设计与施工、主缆索股牵引新系统的形成、钢箱梁吊装专用设备研制等关键技术研究的方法、过程及结论。其中，无抗风缆猫道在非正交风作用下采用六分力试验进行抗风稳定分析，并开展了减振系统研究。通过研究，采用了双线往复门架式牵引系统，自主研制了能实现均衡放索的大吨位主牵引卷扬机、被动放索机构等关键机具。研制开发出的钢箱梁吊装的关键设备-全液压跨缆吊机，具有自主产权，采用模块化设计，并进行计算机集中控制；其起吊能力大，可实现多机组合同步联吊。 Key technology in superstructure construction for suspension bridgesWu Shengdong Feng Zhaoxiang Jiang Bo Abstract: The key technologies in design and construction of the superstructure of Runyang Suspension Bridge, such as the erection of catwalks, the main stand hauling system and special lifting equipment for steel girders, are presented. A six-component test is applied in the wind stability experiments of the catwalk system without wind-resist cables under bevel winds, to study the vibration absorbing system. The hauling system is adopted in accordance with the results of the study. Critical equipment, such as the large tonnage winch and passive unreeling machine, are manufactured. The central computer controlled hydraulic deck erection gantry, modularly designed and operational in groups, is the most important equipment for lifting the steel girders. E-mail: tzbridge@163.com 润扬大桥关键技术研究吴胜东 吉 林 阮 静 摘要：润扬大桥是国家重点工程，建设条件复杂，工程难度大，为提高工程质量，确保工程安全，开展了“润扬大桥关键技术研究”，在解决大桥建设重点和难点问题的基础上，积累了理论和实践经验，形成了长大跨径悬索桥建设成套关键技术。为解决北锚地连墙施工和南锚排桩冻结施工存在的难题，采用了有限元计算和模型试验分析相结合的方法，并利用主动控制技术，建立信息化施工系统，为南北锚碇施工提供了有力的支持，有效地指导了施工过程；为保证润扬大桥混凝土耐久性要求，进行了混凝土耐久性以及寿命评估研究，通过对高性能混凝土配合比的研究，根据不同部位混凝土的具体特点，对大桥混凝土的寿命和耐久性进行了系统的分析预测；润扬大桥悬索桥跨径大，柔度高，钢桥面铺装难度大，研究选择了适合的粘结层，并对铺装体系进行了多参数力学分析，和室内试验研究，提出了钢箱梁面板厚度和适合铺装方案，并确定了钢桥面铺装结构技术标准，有效地指导了后续施工。 Key technologies for construction of Runyang Yangtze River BridgeWu Shengdong Ji Lin Ruan Jing Abstract: Runyang Yangtze River Bridge is constructed amid complicated conditions and a good many other difficulties. The research on key technologies, including about 20 sub-level research projects, is conducted to overcome the difficulties. The FEM analysis and model tests, together with active control techniques and an informational construction system, are employed to deal with the difficulties in construction of the south and the north anchorage pits. Based on the results of tests for high performance concrete mix ratio and erosion, the durability and life-span of the concrete in different parts are assessed to ensure the safety of the bridge. The suspension bridge is so long that the flexibility poses a predominant problem to pavement construction. Combining with the results of laboratory experiments, height of the upper plate of the steel girder and scheme of the pavement construction are proposed. E-mail: tzbridge@163.com 南京三桥清水混凝土施工组织浅谈王 超 谢发祥 李 丹 摘要：清水混凝土施工技术是涉及混凝土施工全过程质量控制的综合技术，是混凝土施工的发展方向。南京三桥指挥部在建设过程中提出了清水混凝土的质量目标，进行了大量的配合比试验和试验墩施工。在施工过程中，对原材料、模板、混凝土浇筑、养护全过程进行了严格的控制，并提出了“首件工程认可制”，以 确保清水混凝土的施工质量。对于不同的结构和施工工法，建设者因地制宜，实行了不同的施工和控制方法，在上部和下部结构施工中，在竹胶板和钢模板上，清水混凝土的质量目标都基本实现，达到了建设伊始提出的清水混凝土质量目标。本文结合南京三桥混凝土工程的施工，对南京三桥清水混凝土施工组织、科研等方面作了介绍，对实现“清水混凝土”这个目标的关键工序作了较详细的说明，并介绍了在南京三桥施工中取得较好效果的施工工艺和方法，可供以后的工程参考。 Management of as-cast finish concrete construction for the 3rd Nanjing Yangtze River BridgeWang Chao Xie Faxiang Li Dan Abstract: (The commanding department of the 3rd Nanjing Yangtze River Bridge, Nanjing 210028, China)
Abstract: The technology of as-cast finish concrete is a synthesized control procedure, a trending direction for construction of concrete buildings. The objective of as-cast finish concrete is brought forward by the commanding department for the 3rd Nanjing Yangtze River Bridge. A good many of concrete fix proportions are experimented and trial piers constructed. The entire procedure of concrete construction, from selecting the raw materials and the molding boards to choosing the procedure of concrete casting and maintenance are strictly controlled to ensure the quality of the concrete. For different parts of the structures, different construction methods are employed. The objective of as-cast finish concrete is realized in the construction of both the superstructures and the substructures. This paper introduces the construction management procedures and the key techniques employed for different parts of the bridge
E-mail: njacao123@sina.com 考虑不平度的桥面铺装动响应分析钱振东 刘 云 黄 卫 摘要：从动力学的角度出发，模拟考虑由桥面的不平度引起的行驶车辆的随机动荷载，应用有限元方法分析了铺装层在车辆随机动荷载作用下的动力响应分布规律，并与以往的移动恒载作用下铺装层的动力响应和静力响应的分析结果做出比较。分析表明，针对铺装层而言，相邻的两块横隔板的跨中位置为最不利荷载位置；考虑桥面不平度情况下铺装层的最大竖向位移和最大横向拉应力的峰值分别是只考虑冲击系数的移动恒载作用下的1.33倍和1.39倍；讨论了车速的变化对铺装层的最大竖向位移和最大横向拉应力的影响。研究结果为铺装层的混合料和结构设计提供了理论依据，对桥面施工及维护提出了严格要求。 Analysis of the dynamic response of steel-deck pavement with roughnessQian Zhendong Liu Yun Huang Wei Abstract:The irregularity of the pavement surface was simulated by using the power spectrum density function, the random load was calculated according to the vehicle vibrating equation, and the dynamic response of the deck pavement under random dynamic load was analyzed by using FEM. The results when considering roughness were compared with those when considering the impact coefficient and static response only. The results indicate that the mid-span of the model is the least favorable load area; the maximum vertical displacement and the maximum transversal tensile stress of pavement are 1.33 times and 1.39 times as much as those when considering only the impact coefficient, respectively. The effects of vehicle speed on the maximum vertical displacement and the maximum transversal tensile stress were studied. This study provides the theoretical basis for the mixture design and structural design of pavement and for requesting a higher quality level in the construction and maintenance of pavement. E-mail: qianzd@seu.edu.cn 钢桥面铺装层结构设计指标近似计算新方法徐勋倩1 黄 卫2 摘要：在行车荷载作用下，钢桥面铺装层的受力与变形较一般公路沥青路面或机场道面复杂得多，也是钢桥面铺装层结构设计的一个重要因素。从使用条件、工程实践、试验研究和受力特点等角度出发，提出钢桥面铺装层结构设计指标：一是铺装层拉应力，二是铺装层表面局部挠跨比。采用有限元方法建立在车载作用下钢桥面铺装层的力学响应计算模型。在结构设计参数常用取值范围内，对不设纵隔板和设置纵隔板两种常用钢桥面铺装层的结构设计指标关键影响因素进行正交敏感性分析。同时，通过逐步线性回归方法拟合出钢桥面铺装层结构设计指标的近似计算公式。得到的近似计算公式的精度检验和工程实例分析结果表明，近似计算公式精度很好，满足工程设计和理论研究的需要。研究结果可为钢桥面铺装层结构设计提供近似计算的新方法。 An approximate method for calculation of design indices of steel bridges deck surfacingXu Xunqian1 Huang Wei2 Abstract: The mechanics and deformation of deck surfacing of steel bridges are, due to wheel loading, more complicated than asphalts for road and airport. Design indices are proposed for the steel bridge deck surfacing, in terms of work condition, application, experimental research and mechanical characteristics. A computer model for the mechanical response of steel bridge deck surfacing under wheel loading is established by using the finite element method. Within regular range of structural design parameters, the key factors of design indices are studied through orthogonal analysis of steel bridge deck surfacing with or without longitudinal clapboard. Approximation formulas of design indices for steel bridge deck surfacing are obtained by using linear regression analysis. A number of tests indicate that the formulas are accurate, making them suitable for engineering and theoretical applications. E-mail: chendak@163.com 大型军用飞机多轮荷载作用下水泥混凝土道面的结构响应凌建明 刘 文 赵鸿铎 摘要：以伊尔-76为例，考虑大型军用运输机复杂起落架构型和多轮荷载的作用特点，基于“地基-道面结构-飞机轮载”的相互作用，并采用弹簧单元模拟道面板的接缝传荷，借助ABAQUS软件建立了足尺9块水泥混凝土道面板的三维有限元分析模型。应用该模型，计算了多轮荷载不同组合作用下水泥混凝土道面的应力和变形，揭示了道面结构的力学响应，即在多轮荷载作用下，道面结构的最大应力位于轮载作用位置的板底部；与8轮荷载组合相比，16轮荷载组合作用下道面结构的应力和变形较小；而且，道面板弹性模量、基层回弹模量和地基反应模量对板底弯拉应力影响显著。 Mechanical responses of rigid airport pavement to multiple-gear military aircraft loadingsLing Jianming, Liu Wen, Zhao Hongduo Abstract: Based on the“subgrade-pavement-aircraft loading”interaction system and using the ABAQUS software, a 3-D finite element model is established for analyzing the mechanical responses of cement concrete airport pavement to multiple-gear military aircraft loadings. It consists of nine full-scale slabs with joint loading-transfer effect. Choosing IL-76 as the aircraft load, the mechanical responses of pavement to different groupings, 8 wheels and 16 wheels, of aircraft multiple-gear loadings are analyzed. It is shown that the maximum tensile stress in the pavement occurs at the bottom of the slab, corresponding to the positions of wheels for both wheels groups, that the tensile stress and the deformation of the pavement under two 8-wheeled gears are smaller than that under one 8-wheeled gear, and that the elasticity modulus of the slab, the resilience modulus of the base and the reaction modulus of the subgrade all have significant effects on the mechanical responses of the pavement. E-mail: jmling01@yahoo.com.cn 软土地区深基坑变形特性分析李 琳 杨 敏 熊巨华 摘要：随着地下空间开发利用规模的加大，基坑工程向更深更大的方向发展。本文就杭州和上海软土地区46个成功深基坑的实测结果进行了研究和总结，分析了基坑开挖深度与最大侧移及其位置的关系，分析了当前基坑开挖深度和所采用支撑系统相对刚度之间的关系。由于抗隆起稳定安全度与基坑变形的关系密切，本文就实测数据进行分析并建立了抗隆起稳定安全系数与围护体最大侧移和墙后最大地面沉降与之间的关系。并对随深度增加后深基坑的变形控制标准提出自己的观点。通过实测数据的分析，有以下结论：随着基坑深度的增大，由于支撑系统的相对刚度迅速增长，使得最大相对侧移值并没有增大，最大侧移位置一般发生在开挖面附近，随基坑深度的增加有向上移动的趋势，抗隆起稳定安全度的提高对减小基坑的变形具有重要的作用，随着基坑深度的增加，基坑的变形在超出当前规范的控制标准时亦可实现基坑自身和周围环境的安全。 Analysis of the deformation characteristics of deep excavations in soft clayLi Lin Yang Min Xiong Juhua Abstract: Excavations are becoming deeper and larger with the increasing scale of underground space exploitation. In this paper, 46 case histories of deep excavations in soft clays in Hangzhou city and Shanghai city are summarized and studied, the relationships between the excavation depth and the magnitude and location of the maximum lateral displacement, and the excavation depth and the relative stiffness of the supporting system are analyzed. As the heave-resistant stability is strongly related with the deformation of the excavation, the relationships between the safety factor of heave-resistant stability and the maximum lateral displacement and the maximum ground surface settlement are analyzed and established. Suggestions on the deformation control criterion for deep excavations are put forward. The conclusions include: 1) with the increase in the depth of excavation, the maximum relative lateral displacement tends to occur in the vicinity of the excavation face and the location tends to move upwards; 2) Increase in heave-resistant stability has important effect on decreasing the deformation, and the excavation as well as its surrounding environment may remain safe even when the deformation exceeds the control criterion prescribed in the current design code. E-mail: liilinn@126.com 老填埋场改扩建中的关键环境岩土技术问题张乾飞1,2 王艳明2 徐永福1 李 锐1 摘要：老填埋场由于采用简易填埋方式和传统填埋作业工艺，对区域土壤、地下水、地表水、大气都存在不同程度的环境污染问题。本文通过对国内外老填埋场改扩建工程的总结分析，指出垃圾堆体稳定、垃圾沉降、渗沥液迁移扩散问题是老填埋场改扩建中的关键岩土技术问题。垃圾堆体稳定主要涵盖新老垃圾堆体的局部稳定、整体稳定、接触面稳定问题，垃圾沉降包括过大沉降和不均匀沉降问题，渗沥液迁移扩散包括填埋场渗沥液迁移分析和地下水污染防治等问题。针对这三大问题，对其机理成因、模型方法、扩建工程措施、老场改建措施等方面进行归纳总结，结合具体工程对这些问题的研究成果进行综述，并从工程技术角度提出了初步解决方案，明确了需要进一步解决和研究的问题，为今后国内填埋场的改扩建指明了发展方向和技术改进途径。 Key geotechnical problems in the reconstruction and expansion of existing MSW landfillsZhang Qianfei1,2 Wang Yanming2 Xu Yongfu1 Li Rui1 Abstract: Due to the utilization of simple fill methods and conventional operation techniques in the construction of landfills in the past, the environmental pollution of soil, groundwater, surface water and the atmosphere is a common problem for existing landfills. Through summarizing and analyzing some of the existing Municipal Solid Waste landfills both at home and abroad, it is found that landfill stability, MSW settlement, and leachate migration and diffusion pose key geotechnical problems to the reconstruction and expansion of existing MSW landfills. Correspondingly, the mechanisms, modeling methodologies, parameters, and engineering measures are summarized, the relevant research results and their applications are overviewed, and directions for further research are pointed out. E-mail: zhang_qf.gp3@smedi.com 地铁振动荷载下隧道周围饱和软黏土的孔压发展模型唐益群1，2 张 曦1 赵书凯1 王建秀1，2 周念清1，2 摘要：以上海地铁2号线静安寺站－江苏路站区间隧道周围饱和软黏土为研究对象，以现场连续监测资料为基础，利用室内GDS（多功能循环三轴试验系统）试验仪器，探求地铁隧道周围不同深度饱和软黏土的孔隙水压力发展规律。通过室内GDS试验，提出了振动荷载作用下饱和软黏土中孔隙水压力发展模型，并利用现场实测资料对该模型进行修正，最终得到地铁行车荷载作用下饱和软黏土中孔隙水压力发展模型。 Model of pore water pressure development in saturated soft clay around
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