上海铁路南站钢屋盖结构设计

汪大绥 周建龙 李 时
（上海华东建筑设计研究院有限公司，上海200002）

摘要：上海铁路南站是上海西南地区的交通枢纽，其钢屋盖采用圆形平面，最大直径为275 m，由径向布置的18根Y形主梁和位于中心的顶压环组成，并布置了主索和环索以提高屋盖的抗扭刚度。屋盖体系支承在内、外两圈共54根柱子上，其中外柱设有斜索以提高结构体系的抗侧刚度。大跨度空间结构的特殊风荷载、由温度变化产生的胀缩效应引起的侧向力、结构的整体稳定性以及复杂节点的受力特性成为主要的设计难点。文中介绍了针对上述问题进行的理论分析和试验研究。根据风洞试验的结果并考虑了结构在脉动风荷载作用下的动响应，得到了对应不同响应的等效风荷载；通过在外柱顶设置弹性支座，部分释放了由于温度变化产生的侧向力；通过对整个屋盖体系以及单根主梁分别进行非线性有限元分析，得到了结构的整体稳定系数；通过节点有限元计算，根据应力分布对节点构造进行设计优化，保证了重要节点的安全可靠。
关键词：钢屋盖；工程设计；风洞试验；弹性支座；整体稳定；有限元分析

Design of roof structure for Shanghai South Railway Station

Wang Dasui Zhou Jianlong　 Li Shi
（East China Architectural Design & Research Institute CO.，LTD，Shanghai 200002, China）

Abstract: The roof structure of the Shanghai South Railway Station is a circular spatial structure with a diameter of 275 m. Its design，analysis and experimental studies are presented in this paper. Wind tunnel experiment was performed and equivalent static wind loads based on the experimental data and random vibration theory were employed in the design. The large lateral thrust due to temperature variations is reduced by placing a spring support on top of the outer columns. Global stability coefficient of the roof，in terms of the ratio of ultimate load to the design load, is obtained from a nonlinear finite element analysis of the entire structure as well as individual main beams. Via FEM analysis，structural optimization was performed on the basis of stress distributions to insure the safety of the key connections.
Keywords: roof structure；design；wind tunnel experiment；spring support；global stability；FEM analysis
E-mail: dasui_wang@ecadi.com

再生混凝土框架抗震性能的试验研究

孙跃东^1,2 肖建庄¹ 周德源¹ 张 鹏²
（1. 同济大学， 上海 200092；2. 山东科技大学， 山东青岛266510）

摘要：在保持竖向荷载恒定的情况下，对3榀再生骨料掺量为30％、50％和100％的再生混凝土框架和1榀天然混凝土框架进行了水平低周反复荷载试验，研究了再生混凝土框架的破坏机制、承载力、滞回特性、延性、强度退化、刚度退化和耗能等性能，并和普通混凝土框架进行对比分析。试验发现再生混凝土框架为“强柱弱梁”的破坏类型，最大水平承载能力比普通混凝土框架低2.3%～15.7%，位移延性系数在3.91~4.54之间，和天然混凝土框架相比耗能能力没有明显降低。试验结果表明再生混凝土框架具有良好的抗震性能，应用于工程实际是完全可行的。
关键词：再生混凝土；框架；位移延性；滞回曲线；刚度退化；耗能

An experimental study on the seismic behavior of recycled concrete frames

Sun Yuedong^1,2 Xiao Jianzhuang¹ Zhou Deyuan¹ Zhang Peng²
（1. Tongji University，Shanghai 200092，China；
2. Shandong University of Science and Technology，Qingdao 266510，China）

Abstract: Experiments of three recycled aggregate concrete frames (composed of 30%,50％,100％ recycled aggregate)and one conventional concrete frame，as the reference basis, under low-cyclic horizontal and constant vertical loads were performed.　 The seismic behavior of recycled concrete frames, such as the failure patterns, hysteresis loop, displacement ductility, deterioration of stiffness and energy dissipation, etc.，was studied and a comparison of such behavior was made with that of the reference concrete frame. The test results indicate that concrete frames using recycled aggregates show improved seismic performance, as evidenced by a failure pattern of“strong column and weak beam”and a displacement ductility factor of 3.91~4.54. Further, its maximum horizontal bearing capacity is lowed by 2.3%～15.7% than that of the reference frame. On the other hand, no clear indication on the energy dissipation capability is shown. This study concludes that the use of recycled aggregate concrete frames for civil engineering structures is quite feasible.
Keywords: recycled concrete； frame；displacement ductility； hysteresis loop； deterioration of stiffness；energy dissipation
E-mail: yds1236@eyou.com

大跨度索杆张力结构的预应力分布计算

蔺 军^1,2 董石麟¹ 王寅大² 高继领²
（1. 浙江大学，浙江杭州 310027；2. 江苏沪宁钢机股份有限公司，江苏宜兴 214231）

摘要：针对多自应力模态与机构位移模态索杆张力结构可行预应力分布求解的最复杂情形，为得到一种具有一定普遍意义的预应力优化求解策略，以该结构体系的一种新形式——大跨度环形平面空间索桁张力结构为基础，考虑其几何拓扑形式多样的特点，应用结构平衡矩阵理论与代数奇异值分解算法，通过对结构模态矩阵的分解变换及其组合运算，提出了一种可依据结构预应力分布的不同优化目标进行求解的新方法——目标选择优化法，使多自应力模态索杆张力结构体系的可行预应力分布求解工作得以便捷的实现。在此基础上，对大跨度索杆张力结构的预应力分布计算方法分三类进行了较为全面的总结；通过三种不同形式新型空间索杆张力结构的可行预应力分布求解算例，验证了上述计算方法的简捷与有效。
关键词：大跨度；索杆张力结构；多自应力模态；可行预应力分布；预应力优化

Calculation of prestress distribution for large-span cable-strut tensile structures

Lin Jun^1,2 Dong Shilin¹ Wang Yinda² Gao Jiling²
(1. Zhejiang University, Hangzhou 310027, China；
2. Jiangsu Huning Steel Structure & Machinery Co., Ltd， Yixing 214231, China)

Abstract: Based on the study of a new type of large-span structure, i.e. a spatial cable-truss tensile structure with an annular plane and complex geometric topology, a new method of prestress optimization using object-selection optimization was proposed . The main objective of the aforementioned method is to solve the complicated problem of feasible prestress distribution in cable-strut tensile structures with multi states of self-equilibrium stress and modes of mechanism displacement. In the proposed method, the modal matrix technique of decomposition and assembly operation, theory of structural equilibrium matrix and algebraic singular value decomposition method were employed. The method has a simple calculation format and can accomplish different objectives of structural prestress optimization. Three different ways in calculating the feasible prestress distribution in cable-strut tensile structures were summarized, and numerical results for three different types of structural systems were obtained to demonstrate the simplicity and validity of the proposed method.
Keywords: large-span；cable-strut tensile structure；multi states of self-equilibrium stress；feasible prestress distribution; prestress optimization
E-mail: linj2005@126.com

非杆系钢筋混凝土结构配筋设计方法

徐 强¹ 吴胜兴²
(1.上海建工集团，上海 200050；2.河海大学，江苏南京 210098）

摘要：针对当前非杆系钢筋混凝土结构配筋设计过程中 “弹性应力图形法”无法对材料非线性特征、裂缝形态和钢筋应力等进行分析的不足，提出三维弹性有限元和二维非线性有限元方法相结合的复合型配筋设计方法。通过对复合型方法中“弹性应力等效原则”和“平面子结构理论”的研究，从理论上论证了复合型设计方法的可行性和合理性，给出了具体的技术路线和计算分析流程，并通过程序开发解决了三维弹性有限元计算结果和二维非线性有限元模型之间过渡环节数据管理和传递的问题。将此方法应用在龙滩导流隧洞进水口结构和苏通大桥桥墩承台结构配筋设计和优化中，对不同配筋情况下结构的裂缝形态、裂缝宽度、裂缝深度和钢筋应力等进行了深入研究，并以此得出了最优的配筋设计方案。
关键词：有限单元法；平面子结构；裂缝宽度；钢筋应力

Reinforcement design method for non-member reinforced concrete structures

Xu Qiang¹　 Wu Shengxing²
(1. Shang Hai Conctruction Group, Shanghai 200050，China；
2. Hohai University， Nanjing 210098, China)

Abstract: Based on three-dimensional elastic FEM and two-dimensional non-linear FEM, a composite reinforcement design method is proposed for non-member RC structures. This method overcomes the shortcoming of the elastic stress graph method which is inadequate in handling the analysis of non-member RC structures involving material nonlinearity ，crack pattern and stress calculations in steel reinforments. . The key methods of elastic tress equivalence and plane substructure are studied，and the feasibility and rationality of the composite method is proven. The specific problems in intermediate data management and data transfer are solved. This composite method is employed in the reinforcement optimization of the Longtan water-diversion tunnel and the Sutong bridge pier. The calculation results include crack form, crack depth, crack width and stress distribution in steel.
Keywords：FEM；plane substructure；crack width；stress distribution in steel
E-mail：x_u_qiang@163.com

中原地区住宅建筑结构活荷载调查与统计分析

陈 淮 葛素娟 李静斌 孙增寿
（郑州大学，河南郑州450002）

摘要：从调查中原地区城镇住宅楼面活荷载出发，建立了持久性及临时性活荷载概率模型。经检验，统计荷载均服从极值I型分布。从调查统计所得的活荷载统计参数出发，根据Turkstra荷载组合原则，得出中原地区城镇住宅建筑结构在设计基准使用期内活荷载组合最大值的统计参数。针对不同使用功能的房间，分别按照79.1％分位值和97.4％分位值计算出代表各类型房间的楼面活荷载标准值，并与荷载规范中住宅楼面活荷载标准值的单一取值相比。计算结果表明，与原规范值（GBJ 9－87）相比，不同使用功能房间的活荷载标准值是不同的，有高有低，且活荷载标准值应有所提高，这也是与新规范值（GB 50009-2001）相一致的。结果反映了中原地区城镇住宅不同使用功能房间活荷载标准值的变化，可为荷载规范的进一步修订提供参考。
关键词：中原地区；住宅；活荷载；调查；统计；分析

Survey and statistical analysis of live loads of residential buildings in the central plains region

Chen Huai Ge Sujuan Li Jingbin Sun Zengshou
(Zhengzhou University，Zhengzhou 450002, China)

Abstract：Based on the survey of the floor live loads of residential buildings in the central plains region, probability models for both the durable and temporary live loads are established. The hypothetical distributions are tested with χ2 tests and the statistical loads are found to follow an extreme I-type distribution in each case. Based on the statistical parameters of the permanent live loads and the temporary live loads, also the Turkstra load combination principle, the maximum value of LT statistical parameters for live loads combinations is obtained for design of the residential buildings in the central plains region. For a room with different functions, the standard values, which represent the floor live loads of the room with the specified functions, are calculated in accordance with 79.1%-fractile and 97.4%-fractile，respectively. These standard values of residential floor live loads are compared with those specified in the load criteria of the design code. The analysis results show that, when compared with the previous criterion（GBJ 9－87）, a room with different functions has different standard values which may be higher or lower than the value given in the criterion. Therefore, standard values of the floor live loads should be increased. This conclusion is consistent with the new criterion (GB 50009-2001).
Keywords: central plains region；residential building；live load；survey；statistics；analysis
E-mail: chenh@zzu.edu.cn

预应力蛋形消化池振动台试验研究

李 杰¹ 陈华明¹ 陈建兵¹ 范民权² 彭春强²
（1. 同济大学，上海200092；2 .上海市政工程设计研究院，上海200092）

摘要：分别输入不同加速度峰值的El-Centro波和广州人工波，对1:8缩尺的预应力蛋形消化池模型进行了模拟地震振动台试验研究。对模型试验结果进行了加速度、位移、应变反应分析，并与有限元模型计算结果作了对比。发现在试验过程中，空池模型和半池水模型主要处于弹性阶段，局部有非线性反应出现；充水导致结构的基频降低；充水对中腹部以下壳体与对中腹部以上壳体产生相反方向的影响；不同的地震波输入对结构反应产生不同的影响，广州人工波下的结构反应较之输入相同加速度峰值的El-Centro波为大；有限元模型的计算结果与试验结果吻合较好。研究结果表明预应力蛋形消化池具有良好的抗震性能，三维流固耦合有限元分析模型以及时程分析计算方法是合理、可行的。
关键词：预应力蛋形消化池；振动台试验；抗震性能

An experimental study on prestressed egg - shape digesters

Li Jie¹ Chen Huaming¹ Chen Jianbing¹ Fan Minquan² Peng Chunqiang²
（1. Tongji University，Shanghai 200092，China；
2. Shanghai Municipal Engineering Design Institute，Shanghai 200092，China）

Abstract: The seismic performance of prestressed egg-shaped digesters (PESD) is studied. A structural model of a 1/8 scale was designed and tested on the shaking table with two earthquake peak accelerations, namely the El Centro and artificial Guangzhou earthquakes. The acceleration, displacement and strain responses were analyzed and compared with the results from FEM modeling. It is found that the half-full model and the empty model mainly assume linear-elastic behavior with only localized non-linear effects. The filled water has apparently reduced the natural frequency of the PESD. The coupling interaction between water and the shell enhances the responses below the middle plane and reduces the responses above the middle plane of the model. Different seismic excitations have distinct influences on the responses of the PESD because of the fact that different frequency spectra and the amplification factors under GZR excitation are greater than those under El-Centro excitation. The calculated results of FEM model agree well with those of the shaking table tests. The results indicate that PESD has good seismic resistances and the FEM model appears to give both rational and reasonable predictive results.
Keywords: prestressed egg-shape digester; shaking table test; seismic performance
E-mail: Lijie@mail.tongji.edu.cn

扣件式钢管支模架稳定承载能力研究

袁雪霞¹ 金伟良¹ 鲁 征¹ 刘 鑫¹ 陈天民²
（1.浙江大学，浙江杭州 310027；2. 浙江省建设投资集团有限公司，浙江杭州310012）

摘要：在直角扣件抗扭刚度试验基础上，考虑扣件连接的半刚性，建立了扣件式钢管支模架稳定承载能力分析的三维有限元模型。采用线性屈曲和非线性屈曲分析方法计算支模架的稳定承载力，结果表明线性屈曲所得的稳定承载力要大于非线性稳定计算结果，尤其是在有初始缺陷时由线性屈曲所得的稳定承载力是不尽合理的。然后采用非线性屈曲方法，计算了不同搭设变量下的稳定承载力，并表示为工程上常用的计算长度系数。对稳定承载力的影响因素进行了分析，指出支模架的初始缺陷、扣件半刚性对支模架稳定承载力的影响比较显著，扣件螺栓拧紧力矩定为40N·m是经济合理的。本文的研究成果可作为扣件式钢管支模架稳定性设计的依据。
关键词：扣件式钢管支模架；半刚性连接；稳定承载力；线性屈曲；非线性屈曲；初始缺陷

A study on the stability bearing capacity of fastener- style tubular steel formwork-supports

Yuan Xuexia¹ Jin Weiliang¹ Lu Zheng¹ Liu Xin¹ Chen Tianmin²
（1. Zhejiang University, Hangzhou 310027, China；
2. Zhejiang Construction Investment Group Co., Ltd，Hangzhou 310012 ,China ）

Abstract: Considering semi-rigid connections, a 3-D FEM was established to simulate the fastener-style tubular steel formwork-support and the analysis was performed together with an experimental study of the torsion stiffness of right couplers. Both the linear and nonlinear buckling techniques were employed to determine the stability of the formwork-supports. In the nonlinear analytical model, Initial imperfection, plastic behavior and large deflection response of the formwork-supports were taken into account. Numerical results indicated the linear buckling loads were higher than that obtained from the nonlinear stability analysis. Nonlinear buckling analysis was employed to calculate the stability bearing capacity for cases of different design variables, and then the results were converted into effective length coefficients that are generally used in practice. The influence factors on the stability bearing capacity were studied. It was pointed out that the effects of initial imperfection and semi-rigid connection on the stability bearing capability are important, also a bolt tightening torque of 40N·m was found to be quite reasonable.
Keywords: fastener-style tubular steel formwork-support；semi-rigid connection；stability bearing capacity；linear stability；nonlinear stability；initial imperfection
E-mail: xxyuan@zju.edu.cn

空间足尺薄柔构件钢框架滞回性能试验研究

陈以一^1,2 吴香香¹ 田 海¹ 童乐为¹
（1.同济大学，上海200092; 2.同济大学土木工程防灾国家重点实验室，上海 200092）

摘要: 进行了两个空间钢框架的滞回性能试验。框架构件均为宽厚比较大的H形截面，按实际工程尺寸制作。试验结果显示板件宽厚比和柱子轴压比是影响这类结构承载性能的主要因素，构件端部的局部屈曲导致结构破坏的开始并降低了结构的延性和耗能能力。基于试验结构抗震能力及其地震需求的分析，提出了这类钢框架的抗震设计概念：相对小震水平的地震作用，结构弹性设计须留有必要的承载力储备，以保证大震作用下结构的安全性。试验表明，符合这一要求的薄柔构件钢框架的弹性刚度能满足小震时的变形要求，结构的变形能力能满足大震作用下的延性要求。试验结构的数值分析结果与试验结果吻合良好。
关键词：空间钢框架；滞回性能试验；局部屈曲；薄柔构件；抗震设计

Experimental study on the hysteretic behavior of full-scale
spacial steel frames composed of non-compact members

Chen Yiyi^1,2　 Wu Xiangxiang¹　 Tian Hai¹　 Tong Lewei¹
（1. Tongji University，Shanghai 200092，China；2. State Key Laboratory for Disaster Reduction in Civil Engineering，Tongji University，Shanghai 200092，China）

Abstract: Two full-scale spatial steel frames were tested under vertical and cyclic horizontal loads. The frame members are H-shaped steel elements of large width-to-thickness ratios. Testing results show that the width-thickness ratio and the ratio of axial force at columns are the key factors influencing the structural performance of a steel frame composed of members with non-compact elements. It is also shown that structural failure commences with the local buckling at the end of members, which also causes the loss of ductility and energy-dissipating ability of the structure. Based on the analysis of seismic capacity of the specimen, a design concept considering the special features of this type of frames is proposed, i.e. for the sake of the safety in rarely occurred earthquakes, the required resistance of the frame should be kept at a relatively high level as opposed to frequently occurred earthquakes. Test results indicate that the frames meeting the aforementioned requirement have sufficient stiffness and deformation capacity to satisfy the different deformation demands for seismic actions at different hazard levels. Numerical analyses are in good agreement with the experimental measurements.
Keywords: spatial steel frame; testing on hysteretic behavior; local buckling; non-compact member; seismic design
E-mail: yiyichen@mail.tongji.edu.cn

不同土性的地基－结构动力相互作用振动台模型试验对比研究

陈跃庆^1,2 　吕西林¹ 李培振¹ 陈 波³
（1. 同济大学土木工程防灾国家重点实验室，上海 200092；
2. 武汉市城市建设投资开发集团有限公司，湖北武汉 430050；
3. 广州市建设科技委员会办公室，广东广州 510030）

摘要：通过结构－地基动力相互作用（SSI）体系的振动台模型对比试验，研究了不同土性的地基条件对动力相互作用效果和规律的影响。在试验现象方面发现，地基土越软弱，结构沉降和倾斜越大；不同土性条件下结构裂缝形态相似，但土越硬，裂缝出现越早，发展也越严重。在体系动力特性方面发现，SSI体系频率均小于不考虑SSI的结构自振频率，阻尼比大于结构材料阻尼比，但不同土性条件时由于土、基础、结构三者刚度比不同，SSI对动力特性的影响程度和机理存在差异。在地震反应方面发现，土越硬，加速度反应的峰值放大系数越大；加速度反应的主要组成成分和频谱特征是，土较软时以基础转动引起的摆动分量和平动分量为主；土较硬时以结构弹塑性变形分量为主。结果表明在不同地基土性条件下，结构－地基动力相互作用具有相似的规律，但其效果和机理存在差异。
关键词：不同土性；结构－地基；相互作用；振动台试验；地震反应

Comparative study on the dynamic soil-structure interaction
system with various soils by using shaking table model tests

Chen Yueqing^1,2 Lü Xilin¹ Li Peizhen¹ Chen Bo³
(1. State Key Laboratory for Disaster Reduction in Civil Engineering, Tongji University，Shanghai 200092, China；2. Wuhan Urban Construction Investment & Development Group Co.，Ltd, Wuhan 430050，China；3. Office of Guangzhou Construction Science and Technology Committee，Guangzhou 510030，China)

Abstract: Through comparing the shaking table tests on dynamic Soil-Structure Interaction (SSI) systems, the effects of various soils on SSI are studied. Test results indicate that the softer the soil is, the larger the subsidence and inclination of the superstructure become. The crack patterns in the superstructure are similar under various soil conditions, but the cracks appear earlier and develop more severely if the soil is hard. The natural frequency of the SSI system is less than that of the structure when SSI is not taken into account and its damping ratio is larger than that of structural material. But the mechanism and degree of these effects is quite different, because the relative stiffness ratios between soil, foundation and superstructure are different under various soil conditions. The seismic response indicates that the harder the soil is, the larger the magnification coefficient of the acceleration response is. The acceleration response of soft soil is mostly composed of rocking and swing whereas hard soil exhibits elastic and plastic deformations. The results indicate that there exist similar behaviors of SSI under various soil conditions, although the mechanism and degree of these behaviors are different.
Keywords: various soil；soil-structure；interaction；shaking table test；seismic response
E-mail: lxlst@mail.tongji.edu.cn

超高层钢结构建筑动力特性与抗震性能的有限元分析

王元清¹ 黄 怡¹ 石永久¹ 陈 宏² 温四清³
（1．清华大学，北京 100084；2．清华大学建筑设计研究院，北京100084；
3．中信集团武汉建筑设计院，湖北武汉430014）

摘要：武汉国际证券大厦共68层，总高度为331.3m，结构底部为钢筋混凝土筒中筒结构过渡到上部框架-支撑钢结构，并沿高度方向设置3道水平加强层，整体结构形式复杂，纵向刚度变化大，对抗震要求较高。抗震规范要求，对于此类复杂结构的抗震分析，应采用不少于两个的不同的力学模型，故利用大型有限元计算软件ANSYS，对其进行了抗震性能分析。包括结构动力特性分析，振型分解反应谱方法和时程分析方法分析常遇地震作用下的结构的变形和内力，并将计算结果和专业软件SATWE的计算结果进行对比。计算可见建筑物刚度突变的楼层为薄弱层，需特别重视；应注意多维地震作用下的结构整体性能分析。结构符合国家现行规范要求，计算方法和结论对于运用有限元软件计算超高层建筑有借鉴价值。
关键词：超高层钢结构；反应谱分析；时程分析；有限元；抗震

Finite element analysis on dynamic characteristics and
seismic resistance of super high-rise steel structures

Wang Yuanqing¹　 Huang Yi¹　 Shi Yongjiu¹　 Chen Hong²　 Wen Siqing³
（1.Tsinghua University，Beijing100084，China；
2. Architectural Design and Research Institute of TsinghuaUniversity，Beijing100084，China；
3. Architectural Design Institute of Wuhan，Wuhan 430014，China）

Abstract: Wuhan International Securities Mansion is a super high-rise steel braced frame with horizontal stiffness-strengthened stories. The stiffness of the building varies considerably along its vertical direction, inducing complicated seismic properties. In this paper, the seismic behavior of the mansion is analyzed by using a commercial finite element software, ANSYS. The analysis includes determination of dynamic characteristics of the structure and the response of the building under small earthquakes. The calculation results, including deformations and member forces are compared with those computed from a specialized software, SATWE. Analysis results indicate that the stories with sudden change in structural stiffness show less resistance againt the earthquake and they require special attention in design. Under multidimensional earthquakes, the analysis to determine the integrated performance of the structure is necessary. The steel structure that has been designed conforms to the requirement of the Chinese codes.
Keywords: super high-rise steel structure；spectrum analysis；time-history analysis；FEA；seismic
E-mail: huangyi98@mails.tsinghua.edu.cn

BP神经网络在大跨斜拉桥的斜拉索损伤识别中的应用

杨 杰^1,2 李爱群² 缪长青²
（1. 南京航空航天大学，江苏南京 210016；2. 东南大学，江苏南京 210096）

摘要：针对润扬长江公路大桥北汊斜拉桥的拉索损伤进行了520种工况的动力计算。定义了归一化固有频率，并且分别分析了拉索损伤位置和损伤程度对归一化固有频率的影响。通过对比研究得出以下结论：拉索损伤位置对不同阶固有频率的影响模式有本质的差异；同一拉索位置处，不同的损伤程度对各阶固有频率的影响模式相似；第4、6、7阶归一化频率对拉索损伤位置不敏感；其他各阶归一化固有频率的分布较为开展，分别包含了损伤模式的个性化信息。据此建立了描述7维损伤模式映射空间的BP神经网络，分别采用不同工况组的数据进行训练和识别，对该方法进行了验证。并且定义了识别误差评价数作为描述识别效果的定量指标。
关键词：斜拉桥；BP网络；损伤识别；拉索损伤

Application of BP neural network to cable damage identification
for long span cable-stayed bridges

Yang Jie^1,2 Li Aiqun² Miao Changqing²
（1. Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China;
2. Southeast University，Nanjing 210096，China）

Abstract: The author calculated 520 cable-damage cases of the Runyang cable-stayed Bridge (north bridge) crossing the Yangtse River. By defining a normalized natural frequency, one may find the location and extent of cable damage with respect to the changes on the normalized nature frequency. Careful comparison reveals the following: ①There is intrinsic difference in the patterns of location versus frequency, whereas the patterns of extent versus frequency are similar; ②While the fourth, sixth and seventh frequencies are not sensitive to cable damage location, the distribution patterns of the other frequencies are rather spread. There upon, a BP neural network describing the 7-dimension mapping space of damage pattern was founded. The neural training and identification based on the different damage cases validated the method, and an evaluation number of identification error was defined to quantify the identification effect.
Keywords: cable-stayed bridge; BP neural network; damage identification; cable damage
E-mail: mryangjie@gmail.com

预应力混凝土箱梁桥竖向预应力损失的实测与分析

方 志 汪 剑
（湖南大学 湖南长沙 410082）

摘要：基于某大跨预应力混凝土连续箱梁桥腹板竖向预应力的现场长期测试结果，对箱梁竖向预应力的各种损失进行了分析。结果表明：就所研究的情形而言，实测竖向预应力总损失可达其初始张拉应力的45%，锚具变形、钢筋回缩及接缝压缩等引起的损失占其总损失的53%。按现行公路桥规（JTG D62-2004）中确定纵向预应力损失的方法计算竖向预应力筋相应的各种损失，所得结果与相应各项损失的实测值基本吻合。对于竖向预应力传力锚固后损失的计算，收缩徐变模型的选取对其结果影响较大。此外还探讨了温度和后续荷载等因素对竖向预应力损失的影响，结果表明：后续荷载作用对竖向预应力损失的影响较小可予以忽略，而混凝土及孔道砂浆中水泥水化热造成的损失可达总损失的18.9%，因此必须予以考虑。
关键词：预应力混凝土；箱梁；竖向预应力；预应力损失

Vertical prestressing loss in the box girder of long-span PC continuous bridges

Fang Zhi　 Wang Jian
（Hunan University，Changsha 410082，China）

Abstract: Based on the long-term field measurement of vertical prestress losses in the box girder of a long-span PC continuous bridge, a detailed analysis of the loss of the vertical prestressing is conducted. It shows that the total loss is about 45 percent of the jacking stress in vertical tendons, and the losses due to anchorage deformation, retraction of tendons and joint compression constitute a large percentage of the total loss. The calculation results, based on the Code for Design of Highway Reinforced Concrete and Prestressed Concrete Bridges and Culverts of China (JTG D62-2004), agree well with the measured results. For the calculated prestress losses after jacking, the model of creep and shrinkage of concrete plays a significant role. Other factors that influence the vertical prestress losses, such as temperature and subsequent loadings, are discussed. It is shown that the influence of the prestress losses due to subsequent loading can be ignored, and that the losses due to the hydration heat should be considered, which constitutes about 18.9 percent of the total loss.
Keywords: prestressed concrete; box girder; vertical prestressing; prestress losses
E-mail: fangzhi@hnu.cn

基于定期检测与遗传算法的大跨度斜拉桥损伤识别

朱劲松¹ 肖汝诚²
（1.天津大学， 天津300072；2.同济大学， 上海 200092）

摘要：为了对运营中的斜拉桥进行安全性评估，首先需要根据实桥测试结果对结构损伤进行初步识别。在斜拉桥定期索力检测与主梁关键截面的应力监测结果的基础上，提出斜拉桥损伤识别的遗传算法，并编制了复杂结构损伤识别的遗传算法程序，通过各期结构检测结果之间的变化来反演检测期间结构参数的变化，据此识别结构损伤位置与程度，保证了在结构参数化有限元模型存在识别误差的情况下也能得到正确的损伤识别结果。宁波招宝山大跨度预应力混凝土独塔斜拉桥的损伤识别仿真结果表明，本文方法和程序具有较高的识别精度，并可推广应用于其它复杂结构的损伤识别。
关键词：桥梁工程；遗传算法；定期检测；损伤识别；斜拉桥

Damage identification of long-span concrete cable-stayed bridge based
on periodic detection and genetic algorithms

Zhu Jinsong¹ 　Xiao Rucheng²
（1.Tianjin University, Tianjin 300072，China；2.Tongji University, Shanghai 200092，China）

Abstract: The primary damage identification based on in-situ test results constitutes an important process for the safety assessment of in-service cable-stayed bridges. Application of Genetic Algorithms to damage identification of cable-stayed bridges, based on the monitored data of cable forces and strains in key sections of the main girders, is conducted. A Damage Detection computer code for complex civil structures developed by the authors is employed to identify the location and extent of damages. The deterioration of structures is calculated according to the monitored data, to make the results of damage identification immune to the errors in the parametric FEM analysis of bridges. The method is tested for a long-span concrete cable-stayed bridge in Ningbo, which has been in-service for four years. The results indicate that the proposed method and the computer code are accurate and reliable.
Keywords：bridge engineering; Genetic Algorithms; periodic detection; damage identification; cable-stayed bridge
E-mail: zhu.jinsong@163.com

城市固体废弃物的动力特性及参数确定

陈云敏¹ 冯世进² 孔宪京³ 唐晓武¹
（1. 浙江大学，浙江杭州 310027；2. 同济大学，上海 200092；
3. 大连理工大学，辽宁大连116024）

摘要：参照杭州天子岭填埋场城市固体废弃物（MSW）主要成分，人工配制固体废弃物试样，利用中型动三轴试验仪研究其在较大应变范围内MSW的动力特性。由于MSW的高压缩性，初始孔隙比不同对试样的动力特性影响不大。建议了归一化动剪切模量和阻尼比与动剪应变依赖关系的取值范围和平均值曲线，并将其与不同塑性指数黏土的动力特性进行对比，可以发现MSW材料剪切模量衰减和阻尼比曲线较好的呈现出中塑性黏土的特征。最后，对城市固体废弃物的动剪切模量Gd和阻尼比D随动剪应变γd的变化曲线进行了拟合,并给出了拟合公式的参数取值。
关键词： 城市固体废弃物；动三轴试验；动剪切模量；阻尼比

Dynamic characterization and parameter identification for municipal solid waste

Chen Yunmin¹ Feng Shijin² Kong Xianjing³ Tang Xiaowu¹
（1. Zhejiang University，Hangzhou 310027，China；2. Tongji University，Shanghai 200092，China；3. Dalian University of Technology，Dalian 116024，China）

Abstract: To investigate the dynamic properties of municipal solid waste (MSW) under large strains, dynamic triaxial tests are conducted by using a moderate-scale triaxial apparatus on MSW samples simulating the compositions of MSW from the Hangzhou Tianziling Landfill. The high compressive property of MSW makes the influence of the initial void ratio insignificant. The variation ranges and average curves of the normalized dynamic shear modulus and the damping ratio versus the dynamic shear strain relationship are proposed and the fitting parameters obtained, which are then compared with those of clays of varying plasticity. It is found that the dynamic properties of MSW are similar to those of clays of medium plasticity.
Keywords: municipal solid waste；dynamic triaxial apparatus；dynamic shear modulus；damping ratio
E-mail: cym@civil.zju.edu.cn

竖向荷载下桩基础的通用分析方法

王 伟¹ 杨 敏² 王红雨³
（1.上海岩土工程勘察设计研究院，上海200002; 2. 同济大学，上海 200092;
3. 宁夏大学，宁夏银川 750021 ）

摘要：应用弹性理论中的变形协调关系、物理方程和力的平衡关系，研究了包含不同桩长、桩半径和刚度特性的竖向荷载作用下桩基础的分析方法。桩侧摩阻力分布采用幂函数有限项级数的表示方式，推导得出了联系桩顶荷载和桩顶位移之间的刚度矩阵，进而根据群桩荷载可方便求得桩基位移，从而形成一种分析竖向荷载下桩基础的通用分析方法。并针对不同的桩基布置形式与应用ANSYS商用软件分析的有限元方法结果进行比较，结果表明本文方法不仅精度上满足要求，而且计算矩阵仅与群桩中桩数相关而与其它变量无关，分析过程更简便。
关键词：桩基础；竖向荷载；位移；侧摩阻力；通用分析方法

A general analysis method for pile group under vertical loading

Wang Wei¹　 Yang Min²　 Wang Hongyu³
（1. Shanghai Geotechnical Investigations & Design Institute, Shanghai 200002，China；
2. Tongji University，Shanghai 200092，China；3. Ningxia University，Yinchuan 750021，China )

Abstract: The analysis method for pile foundations under vertical loading is studied by using the theory of elasticity. Lateral resistance on pile shaft is simulated with power function series. The stiffness matrix relating to the force and displacement at pile top is derived. The results are compared with those obtained from the finite element method (using a commercial software ANSYS）. The comparison indicates that the proposed analysis method is reasonable and it provides accurate numerical solution. Besides, the calculation process involved is relatively simple in that the stiffness matrix is related only to the number of piles in groups.
Keywords: pile foundation；vertical loading; displacement；lateral resistance；general analysis method
E-mail: waye_wang@163.com

软岩崩解物颗粒分布特征研究

苏永华 刘晓明 赵明华
（湖南大学，湖南长沙 410082）

摘要：采集了某高速公路路堤填筑料软岩试样，查明该类软岩的矿物成分和基本物理力学性质。采用洒水和吹晒循环试验，模拟软岩在大气中的自然崩解过程。在试验过程中对崩解物颗粒筛分后进行质量分析，将不同粒径区间内的变化绘成曲线。从其变化趋势发现崩解物颗粒质量变化曲线是自相似的，在统计上是一个分形，并采用盒维数方法计算它的分数维。最终停止崩解时颗粒质量分布曲线的分数维稳定在某一常数。利用稳定分数维作为软岩路基、堤坝修筑施工工艺控制性指标，指导某高速公路路堤工程的施工，获得了质量优良的路基。结果表明分形几何是一种研究软岩崩解机理的有效方法，颗粒质量分布曲线的常分维值可以作为软岩吸水后崩解是否完成的判断标准。
关键词：软岩；膨胀崩解；分数维；施工工艺

Research on the grading of soft rock crumbling pellets

Su Yonghua Liu Xiaoming Zhao Minghua
（Hunan University, Changsha 410082，China）

Abstract: Soft rock samples, employed as a stuffing material for an expressway roadbed, was collected, and the mineral contents and basic mechanical parameters were measured. The natural collapsing process of soft rocks at the atmosphere was simulated through tests of cyclic watering, blowing and sunning. Changes of soft rock scrap mass in various size ranges was graphed based on sifting measurements. It was found that the graphs are self- similar and statistically a fractal. The fractal dimension value of the curves, calculated by using a box dimension method, tended to be a constant after the collapsing stopped. As a controlling index of stuffing materials for construction of expressway roadbed and dyke, the constant fractal dimension was employed to supervise the construction. The results indicate that fractal geometry is an effective approach to study the collapse mechanicsm of soft rock, the constant fractal dimension value of the rock mass distribution curve can be regarded as a criterion to check if the collapse process of soft rocks after absorbing water has indeed ended.
Keywords: soft rock；swelling collapse；fractal dimension；construction technics
E-mail: syh5327@hnu.cn

改进和声搜索算法及其在土坡稳定分析中的应用

李 亮 迟世春 林 皋
（大连理工大学海岸与近海工程国家重点实验室，辽宁大连 116024）

摘要：土坡非圆临界滑动面的寻求是土坡稳定分析的重要步骤，它是一个多极值的优化问题。利用改进的和声搜索算法和修复策略来寻求复杂土坡的临界滑动面及其对应的安全系数，并对改进和声搜索算法与基本和声搜索算法的结果进行了比较，发现改进和声搜索算法比基本和声搜索算法能搜索到更危险的滑动面，原因在于，改进和声搜索算法在每次迭代步中产生多个新解，而基本和声搜索算法中每次迭代产生一个新解。此外，修复策略比惩罚策略更能有效地搜索解空间。结果表明，改进的和声搜索算法和修复策略可以用来进行土坡稳定分析。
关键词：边坡稳定；安全系数；和声搜索算法；修复策略

Improved harmonic search algorithm and its application to soil slope stability analysis

Li Liang Chi Shichun Lin Gao
（The State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China)

Abstract: Locating the critical slip surface of soil slopes is an important step for soil slope stability analysis. It is usually an optimization problem with multiple local minima. This study utilized a modified harmonic search algorithm and rectifying procedure to determine the critical slope surface with the minimum factor of safety of soil slopes. Numerical results so obtained were compared with those using the simple harmonic algorithm. It can be concluded that the factor of safety obtained by using the modified harmonic search algorithm is lower than that by the simple harmonic search algorithm. This is because that several solutions can be generated with the modified harmonic search algorithm, instead of just one solution by the simple harmonic search algorithm. In addition, the rectifying procedure is more useful to the slope stability analysis than the penalty procedure.
Keywords: slope stability；factor of safety；harmonic search algorithm；repairing strategy
E-mail: celldl@palyu.edu.hk

结构－地基开放系统动力相互作用问题的高效解法

刘晶波 谷 音 李 彬
（清华大学，北京 100084）

摘要：应用黏弹性人工边界将结构-地基开放系统转化为近似的封闭系统，利用等效地震波动输入方法将波动散射问题化为波源问题，再采用振型叠加法对近似封闭系统进行分析，由此建立了一种结构-地基开放系统动力反应问题的高效计算方法。采用高效算法分别计算了二维弹性半空间波源问题和地震作用下结构－地基动力相互作用问题算例，并与采用常规的直接时域逐步积分法给出的计算结果进行了对比，由此讨论了高效算法的特点。与常规直接动力分析方法相比，高效算法可以在确保模拟精度的同时，有效降低计算工作量、节省计算时间，并且结构-地基动力相互作用系统的模型越大、自由度越多，高效算法的优越性就越突出，从而为大型结构-地基系统动力相互作用问题数值分析提供了一种高效而精度足够的解法。
关键词：开放系统；封闭系统；结构－地基动力相互作用；波动输入；高效算法

An efficient method for the dynamic interaction of open structure-foundation systems

Liu Jingbo Gu Yin Li Bin
（Tsinghua University, Beijing 100084，China）

Abstract: The structure-foundation system is transformed from an original open system into an approximately closed system through a viscous-spring artificial boundary. In addition, the seismic wave scattering problem is changed to a wave source problem by employing an equivalent seismic wave input. Subsequently, the modal superposition method is adopted to solve the approximated closed system. This procedure is highly efficient in analyzing dynamic structure-foundation interaction problems in the time domain. Two numerical examples are presented to illustrate the characteristics of the proposed method: one is a wave source problem in 2-D elastic semi-infinite space, and the other a dynamic structure-foundation interaction problem under seismic excitations. Comparing with the traditional direct step-by-step integration method, the proposed method, with a sufficient number of mode shapes included, can significantly reduce the computational time with almost the same precision. The results also indicate that the proposed method is more advantageous for solving large structure-foundation systems of many degrees of freedom.
Keywords: open system; closed system; dynamic structure-foundation interaction; input of seismic wave motion; efficient calculation method
E-mail: liujb@tsinghua.edu.cn

基坑开挖及降水引起的地表沉降预测

施成华　 彭立敏
（中南大学，湖南长沙 410075）

摘要：以随机介质理论、渗流理论和土体压密理论为基础，探讨了一种新的基坑开挖及降水引起的地表沉降的计算方法。推导了基坑降水渗降漏斗曲线方程及考虑水的渗流作用的基坑周边土体中有效应力的计算公式，并由此导出了考虑渗流作用的基坑降水地表沉降计算公式，再利用叠加原理，得到最终的由开挖和降水引起的地表沉降分布计算公式。工程实例分析计算结果表明，距基坑周边8～10 m范围以内，基坑开挖和降水引起的地表沉降基本相当，而距坑周20 m以外的地表下沉主要由降水引起，因此基坑降水引起的地表下沉不容忽视。本文推导的计算方法能充分反映基坑降水对周边地表下沉的影响，是一种计算基坑开挖及降水引起的地表沉降的有效方法。
关键词：基坑开挖与降水；地表沉降；随机介质理论；渗流；土体固结

Ground surface settlement caused by foundation pit excavation and dewatering

Shi Chenghua　 Peng Limin
（Center South University，Changsha　 410075，China）

Abstract: Based on the stochastic medium theory, seepage theory and soil consolidation theory, a new calculation method of ground surface settlement caused by foundation pit excavation and dewatering was studied. The settlement equation due to dewatering was derived. Calculation formula for effective stress in the surrounding soils of foundation pit with seepage was investigated, and the formula of ground surface settlement caused by dewatering was thus obtained. Besides, calculation formula of ground surface settlement caused by both excavation and dewatering was derived. Numerical results indicate that: in the area less than 8~10m away from the foundation pit, surface settlement caused by excavation is equal to that by dewatering on the whole, while in the area more than 20m away from the foundation pit, surface settlement is mainly caused by dewatering.
Keywords: foundation pit excavation and dewatering；ground surface settlement；stochastic medium theory；seepage；soil consolidation
E-mail：csusch@mail.csu.edu.cn

核心期刊《土木工程学报》载文被引作者及基金论文定量分析

黄子春¹ 李建国² 王惠翔³
（1. 西安建筑科技大学，陕西西安 710055; 2. 青岛市环境保护监测中心站，
山东青岛 266003; 3. 青岛理工大学图书馆，山东青岛 266033）

摘要：依据北京万方《中国科技论文与引文数据库》和重庆维普《中文科技期刊引文数据库》的数据，对中文核心期刊《土木工程学报》载文在1996年~2005年8月间被国内中文期刊引用情况（包括引用频次、被引论文年代和引用期刊分布），发文作者（包括作者的系统、地区、合作类型分布）及基金论文（包括基金论文数量及基金资助数量，基金论文的资助机构分布）的定量分析，客观揭示该刊在我国学术界的整体水平及主要影响。
关键词：土木工程学报；载文被引；作者调查；基金论文统计；定量分析

Quantitative analysis of papers referenced and funded in the
core-periodical—China Civil Engineering Journal

Huang Zichun¹ Li Jianguo² Wang Huixiang³
（1. Xi’an Univ of Arch.&Tech , Xi’an 710055, China;
2. Qingdao Environment Protection and Monitoring Station， Qingdao 266003, China;
3. Library of Qingdao Technological University，Qingdao 266033，China）

Abstract: Based on the two databases, ‘the Chinese Science and Technology Publications and Citations database’ and‘the Chinese Science and Technology Journal Citations database’, papers in the Journal of Civil Engineering from 1996 to August of 2005 are quantitatively analyzed, including index parameters（index frequency, index time, and distribution of index journal）, author characteristics（system, region and distribution of cooperation type）and funding conditions（number of papers, amount of funds, distribution of funding agency）. The holistic level and important influence of the journal in Chinese academia are objectively revealed.
Keywords: China Civil Engineering Journal；indexed paper；author；funded papers；quantitative analysis
E-mail: whx@qtech.edu.cn