钢管混凝土柱受剪承载力试验

钱稼茹¹  崔 瑶¹  方小丹²
（1.清华大学，北京 100084；2.华南理工大学，广东广州510641）

摘要：为建立钢管混凝土柱的受剪承载力计算式，完成了35根试件的静力加载试验。试件参数包括钢管壁厚、混凝土强度、剪跨比和轴压比。结果表明，剪跨比λ≤0.5施加轴压力的试件为剪切破坏，1.0≥λ＞0.5施加轴压力的试件为剪弯破坏，λ≥0.5未施加轴压力的试件为弯曲破坏；试件有较大的变形能力；钢管混凝土柱的受剪承载力与轴压比、剪跨比有关。建立了由钢管、混凝土和轴压力三部分贡献组成的钢管混凝土柱受剪承载力计算公式，计算值与试验值符合较好，且偏于安全。
关键词：钢管混凝土柱；试验；受剪承载力；计算公式

Shear strength tests of concrete filled steel tube columns

Qian Jiaru¹ Cui Yao¹ Fang Xiaodan²
(1. Tsinghua University, Beijing 100084, China;
2. South-China Polytechnic University, Guangzhou 510641, China)

Abstract: Static loading tests of 35 specimens were carried out to study the shear strength of concrete filled steel tube(CFST)columns. Wall thickness of steel tube, concrete strength, shear-span ratio and axial force ratio were considered as test parameters. Under axial compressive force, the specimens of shear-span ratio λ≤0.5 failed in shear, and the specimens with 1.0≥λ＞0.5 failed in shear-bending, whereas the specimens with λ≥0.5 without axial compressive force failed in bending. The specimens possess large deformation capacity. The shear strength of CFST columns was correlated to the axial force ratio and the shear-span ratio. Based on the test data, a formula, including the contributions of steel tube, concrete and axial compressive force, was developed for calculating the shear strength of CFST columns. The calculated values were in good agreement with the test values and on the safe side.
Keywords: concrete filled steel tube column; test; shear strength; calculation formula

E-mail: qianjr@mail.tsinghua.edu.cn

近断层地震下摩擦型隔震结构与限位装置碰撞反应及防护研究

樊 剑 刘 铁 魏俊杰
(华中科技大学，湖北武汉430074)

摘要: 采用不同的碰撞模型，研究了摩擦型隔震结构（P-F、R-FBI和FPS）在近断层地震作用下与限位装置相碰撞的动态反应特性，给出了不同碰撞的数学表达式以及各模型中参数的具体数值；研究发现，地震中隔震结构若发生碰撞将大大增加结构的层间剪力和加速度反应，且激起结构的高阶振型；不同碰撞模型的计算结果相差在10%以内，但非线性碰撞模型花费的计算时间长，因此在实际工程中采用线性的Kelvin模型精度已足够；上部结构的非线性对碰撞反应有很大影响，碰撞时非线性结构的底层最大剪力较线性结构有很大减小，且层间存在很大的残余位移；同时还研究了基底预留宽度以及上部结构的自振周期对隔震结构碰撞反应的影响；最后提出了加设高阻尼橡胶缓冲器减小隔震结构碰撞反应的防护措施。
关键词：摩擦型隔震结构；近断层地震；碰撞；地震响应

Response and protection of the impact of base-friction-isolated structures and
displacement-constraint devices under near-fault earthquakes

Fan Jian　Lin Tie　Wei Junjie
（Huazhong University of Science and Technology，Wuhan 430074，China）

Abstract: The seismic responses of the impact of base-friction-isolated structures and displacement-constraint devices under near-fault earthquake ground motions are studied by using various impact models. The analytical formulations of various impact models are outlined, and the model parameters studied in detail. The results indicate that the maximum acceleration and the shear force between the floors are significantly increased, and the higher-order modes are exited due to the impact. The differences between the numerical results of various impact models are within 10%, however, the non-linear impact models consume much more computing time, and the Kelvin linear impact model can be effectively employed for actual projects. In comparison with the linear superstructure, the maximum base shear force of the non-linear structure is decreased and the large residual displacement can be detected during the impact. The impact response of base-friction-isolated structures with different system parameters, such as size of gap and superstructure flexibility, is also studied. A protection measure is proposed for reducing the impact response by introducing high-damping rubber bumpers.
Keywords: base-friction-isolated structure; near-fault earthquake ground motions; impact; seismic response

E-mail: fan-jian@126.com

佛山平胜大桥全桥模型试验研究

胡建华¹ 沈锐利² 张贵明¹ 唐茂林² 王忠彬²
（1.湖南交通规划勘察设计院，湖南长沙410008；2.西南交通大学，四川成都610031）

摘要：广东佛山平胜大桥是世界首座独塔、单跨悬吊钢混结合梁的自锚式悬索桥，跨度达350 m。本文利用全桥模型研究这种新型结构的体系转换过程和结构在荷载作用下的响应，重点介绍了该桥全桥静动力试验模型的结构设计及关键技术、试验过程和试验研究结果。自锚式悬索桥的试验模型在满足相似条件方面需要考虑加劲梁压缩变形的影响；在结构体系转换过程中，虽然主缆等的变形是几何非线性的，但由于结构的成桥内力状态与吊索张拉顺序无关，因此各种体系转换过程都能实现要求的线形。无应力长度控制法是确定自锚式悬索桥体系转换过程中的张拉力和结构状态较好的方法；在活载作用下，自锚式悬索桥的受力特性表现为线性的，自锚式悬索桥与地锚式悬索桥力学特性上既有一些相同的地方，又有较大的差异。
关键词：自锚式悬索桥；全桥模型试验；力学特性；吊索无应力长度；结构体系转换

A total bridge model study of the Pingsheng Bridge in Foshan

Hu Jianhua¹ Shen Ruili² Zhang Guiming¹ Tang Maolin² Wang Zhongbin²
(1.Hunan Provincial Communications Planning Survey & Design Institute, Changsha 410008,
China;2.Southwest Jiaotong University, Chengdu 610031, China)

Abstract:Pingsheng Bridge in Foshan is the first single-tower and single-span hybrid girder self-anchored suspension bridge with a main span of 350m. Making use of a total bridge model, the system transition process and structure response are studied. The structure design and key technologies, model test process and static and dynamic test results of the total bridge model are introduced. In the test model of the bridge, the influence of compression and deformation of stiffening girders must be considered to satisfy the similarity conditions. During the course of transition of the structural system, the main cable’s deformation is nonlinear, whereas since the structural internal force is unrelated with the order of hanger tensioning, the demanded line shape can be realized for all the transitions. Control of the unstressed length is a proper method for determining the tensile force and the structure states in the course of transition of the self-anchored suspension bridge. Under live load, the mechanical properties of self-anchored suspension bridges are linear. Some mechanical properties of self-anchored suspension bridges and earth-anchored suspension bridges are alike, while others different.
Keywords: bself-anchored suspension bridge；total bridge model test；mechanical property；unstressed length of hanger；transition of structural system

E-mail: hujianhua@hnjtsjy.com

无背索斜拉桥的概念、设计与施工

彭旺虎 邵旭东 李立峰 张 阳
（湖南大学，湖南长沙 410082）

摘要：长沙市洪山大桥是一座无背索斜拉桥，该类型桥梁的受力特性与常规斜拉桥有较大的不同，造成其设计和施工的特殊性。归纳国内外已建和在建的无背索斜拉桥的一般情况，详细论述其塔梁平衡关系和索、塔倾角的取用准则，根据优化塔、索造价和降低塔重偏差对塔身受力的影响来可以得到塔的合理倾角。进一步介绍洪山大桥的主梁类型和截面型式、若干构造细节和施工过程，分析研究表明钢-混凝土组合脊骨梁更能够适应无背索斜拉桥的受力特点，并具有造价和技术优势；主跨两端特殊的构造设计可以保证塔梁结合部和主跨－辅助跨过渡段的传力平顺；施工中采用桥面预压工艺可以有效改善桥面板横桥向受力状态。
关键词：无背索斜拉桥；概念设计；结构设计；塔梁平衡

The concept, design, and construction of cable-stayed bridges without backstays

Peng Wanghu Shao Xudong Li Lifeng Zhang Yang
（Hunan University, Changsha 410082, China）

Abstract: Hongshan Bridge is a harp-shaped cable-stayed bridge without backstays, located in Changsha. The behaviors of this type of bridge are different from those of the conventional cable-stayed bridge, which make some particularity on structural details and construction method. The newly constructed and in-service cable-stayed bridges without backstays are summarized. The weight balance relationship between pylon and girder and the criterion on determining the angles of pylon and cables are expounded in detail. It is found that the suitable inclination angle of pylon can be obtained via optimizing the cost of pylon and cables and reducing the influence of the weight error on the mechanical characteristics of pylon. The structural type and cross section of the main girder, the special structural details and the construction procedure of the Hongshan Bridge are presented. It is concluded that the steel-concrete composite spine girder structure is advantageous in satisfying the mechanical characteristics of the bridge. The special structural design for the two ends of the main span can ensure smooth transfer of forces between the pylon and the girder and between the main span and the auxiliary span. Moreover, the pre-bending prestressing method is capable of effectively improving the performance of the concrete deck in the transverse direction.
Keywords: cable-stayed bridge without backstay; conceptual design; structural design; weight balance between pylon and girder

E-mail: shaoxd@hnu.cn

桥梁船撞风险评估系统总体研究

耿 波¹ 王君杰¹ 汪 宏² 范立础¹
(1同济大学，上海200092；2重庆交通科研设计院，重庆400067)

摘要：从桥梁工程船撞设计的角度出发，提出了一个桥梁船撞风险评估系统的总体框架，共包括五部分内容：船桥碰撞评估数据库、桥梁船撞安全评估模块、可接受风险准则、主动防撞方案设计和被动防撞方案设计，并阐明了各组成部分之间的逻辑关系。同时对各部分中需要解决的关键问题进行了阐述，主要包括：用于桥梁船撞风险分析的合理船舶分类标准的定制；针对风险事件引入概率设计的思想，研究船撞力荷载与结构抗力的分布函数，提出了利用可靠度对桥梁船撞安全状态进行评估的思路和方法；桥梁船撞可接受风险标准的确定；处于不同风险水平下的桥梁的合理防撞方案的选择与优化设计等。
关键词：船撞桥； 风险评估； 设计

Risk assessment system for bridges against vessel impacts

Geng Bo¹ Wang JunJie¹ WangHong² Fan Lichu¹
（1.TongJi University, Shanghai 200092, China；
2.Chongqing Communications Research & Design Institute, Chongqing 400067, China）

Abstract: For the purpose of bridge design against vessel impacts, a framework of risk assessment system is proposed. The proposed system consists of five sub-systems: data base for vessel-bridge collision assessment, bridge safety assessment module, risk acceptance criteria, active collision-prevention scheme design and passive structure-protection scheme design. The logical relationships between these sub-systems are expounded. The key issues in each of the sub-systems are explained, mainly including: the rational classification criterion of vessels used for risk analysis, the concept of probabilistic design against risk event, and the reliability method used for bridge safety assessment in the presence of studying probabilistic models of vessel impact force and structure resistance, the determination of risk acceptance criteria, the selection and optimum design of rational collision-prevention scheme or structure-protection scheme under various risk levels.
Keywords: vessel-bridge collision; risk assessment; design

E-mail: Gengbo01@163.com

大跨度斜拉桥智能可靠度评估方法研究

朱劲松¹ 肖汝诚² 何立志^３
（1.天津大学，天津 300072；2.同济大学，上海200092；３.北京工业大学，北京100022）

摘要：针对既有大跨度斜拉桥的评估管理系统中的可靠度评估问题，提出了基于RBF网络与Monte Carlo结合的可靠度评估方法。建立了招宝山大桥快速分析的RBF网络模型，网络训练样本按均匀设计方法，考虑几何非线性因素由ANSYS软件分析得到。对运营期的招宝山大桥进行了两类失效模式，三种极限状态下的可靠度评估，并分析了不同活载模式、不同功能函数及不同检测期对可靠度评估结果的影响。分析表明：基于RBF-MC的可靠度分析方法具有速度快、精度高的优点，并能同时计算多极限状态下的结构可靠指标，特别适合在基于可靠度的桥梁管理系统中采用；活载布置方式、选取的功能函数均影响可靠度评估的结果，招宝山大桥不同检测期可靠度水平变化不大,且均处于安全可靠状态。
关键词：RBF网络；Monte Carlo；斜拉桥；可靠度评估；桥梁管理系统

Reliability assessment of large-span cable-stayed
bridges based on artificial intelligence

Zhu Jinsong¹ Xiao Rucheng² He Lizhi³
(1. Tianjin University, Tianjin 300072, China; 2. Tongji University, Shanghai 200092, China;
3. Bejing University of Technology, Beijing 100022, China)

Abstract: A RBF neural network based Monte Carlo method is proposed to evaluate the reliability of existing large-span cable-stayed bridges for bridge assessment & management. A fast simulation RBF neural network model is established for the Zhaobaoshan bridge, and the training sample is obtained according to uniform design and using the ANSYS software for considering geometrical nonlinearities. The reliability analysis of the Zhaobaoshan bridge under two types of failure modes and three limit states and the sensitivity analysis of the live load modes, the limit state functions and the detection periods to the reliability indices are carried out. The results show that several limit states can be considered simultaneously by using the presented method. The accuracy and the efficiency of the RBF-MC method is verified from the simulation. The results of the evaluation are influenced by the live load modes and the limit state functions considered in the analysis. The Zhaobaoshan bridge is safety during the detection period.
Keywords: RBF network; Monte Carlo; cable-stayed bridge; reliability assessment；BMS

E-mail: zhu.jinsong@163.com

地基非线性沉降计算的原状土割线模量法

杨光华^1，2　王鹏华²　乔有梁²
(1. 广东省水利水电科学研究院，广东广州510610; 2. 华南理工大学，广东广州510640)

摘要：地基的沉降计算如何较准确而又简便是工程实践中一直未很好解决的问题。为较好解决地基沉降计算这一重要难题，提出一种原状土割线模量法，就是利用原状土的压板试验曲线，假定压板试验曲线符合双曲线方程，利用Bussinesq解，建立不同荷载水平下土体的等效割线模量。对于实际基础，则根据土体不同深度的应力水平，从压板试验曲线确定原状土的割线模量，然后用于分层总和法进行地基非线性沉降计算，通过试验曲线的验证和实际工程的应用，证明该方法效果较好，可较准确计算地基的沉降。
关键词：原状土；割线模量；分层总和法；非线性沉降

An undisturbed-soil secant modulus method for calculation of
nonlinear settlement of soil foundations

Yang Guanghua^1，2 Wang Penghua² Qiao Youliang²
(1.Guangdong Provincial Research Institute of Water Resource and Hydropower, Guangzhou,
510610;2.South China University of Technology, Guangzhou, 510640)

Abstract: How to calculate soil foundation settlement simply as well as accurately is still an issue not well resolved in engineering design. An undisturbed-soil secant modulus method is presented by using the in-situ plate loading curve that is assumed as a hyperbola. The equivalent secant modulus of the undisturbed soil is determined under different stress levels based on the Bussinesq's solution. Using this undisturbed-soil secant modulus method in combination with layer-wise summation to compute the settlement of a foundation yields results that are in good agreement with the observations.
Keywords: undisturbed soil; secant modulus; layer-wise summation method; nonlinear settlement

E-mail: ygh@gdsky.com.cn

高应变动力试桩中重锤-桩-岩土冲击响应的理论研究

陈久照 温振统 李 廷 张希朝
（广东省建筑科学研究院，广东广州 510500）

摘要：为研究高应变动力试桩中重锤与桩土体系的匹配关系，基于一维行波理论，采用连续杆件模型，建立了研究高应变动力试桩中重锤-桩-岩土冲击响应问题的数值计算模型与算法，用数值分析的结果定量评价了重锤激发桩周及桩端岩土阻力的能力，以及高应变动力试桩中锤重、落距、桩垫刚度、桩径、桩长、岩土性质对检测承载力的影响，从而明确了选择试验锤重时应考虑的各种因素，并用数值分析的结果验证了重锤上测力的新方法的可行性。采用8×103 kg与14×103 kg试桩重锤分别以0.8 m与0.5 m的落距冲击试验桩进行现场试验，试验以及数值分析的结果从实践和理论两个方面有效支持了“重锤低击”原则。
关键词：重锤；桩；岩土；高应变；冲击响应；重锤低击

A theoretical study on the impulse response of hammer-pile-soil
system in high strain dynamic pile test

Chen Jiuzhao Wen Zhentong Li Ting Zhang Xichao
(Guangdong Provincial Academy of Architecture Science,Guangzhou 510500, China)

Abstract: To study the matching relationship between the high strain dynamic test result and the weight of hammer, based on the theory of one-dimensional wave and continuous pole, a numerical model for analyzing the hammer-pile-soil impulse response in high strain dynamic pile test is developed. In order to confirm all factors that should be considered when choosing the hammer weight, by using numerical analysis, the influence of the hammer weight on the stimulated resistance of the surrounding and the bottom soils of the pile is quantitatively evaluated. In the same manner, the influences of the drop elevation, the stiffness of pile cushion, the pile length and diameter, and the soil quality are also studied. The numerical analysis result verifies the new theoretical method. The dynamic tests were conducted by dropping two hammers of 8×103 kg and 14×103 kg in weight and with the falling height of 0.5 m and 0.8 m, respectively. The“heavy hammer and low strike”principle is supported by the in-situ test and numerical analysis.
Keywords: pile; soil; high strain; impulse response; heavy hammer and low strike

E-mail: Oldjiu99@yahoo.com

土压平衡盾构平衡控制理论及试验研究

王洪新^1，2　傅德明²
(1.同济大学，上海200092；2.上海隧道工程股份有限公司，上海200082)

摘要：土压平衡盾构在掘进时有两种平衡状态，一种是盾构与前方土体接触压力和土水压力的平衡，另一种是出土的平衡。两种平衡状态只有在刀盘开口率非常大时才等价。由于面板的挤压作用，开口率较小的盾构两种平衡状态将有较大偏离。出土率是控制土压平衡的重要指标，当其接近100%时，盾构处于出土的平衡掘进状态。盾构掘进时很难直接控制出土率，可通过施工参数间接控制。推导出土率与螺旋机转速、推进速度的定量关系，通过模型试验验证三者关系；推导平衡状态时上述三个参数的关系，该关系可作为通过施工参数控制平衡状态的标准；提出通过模型试验确定平衡状态时参数匹配的方法。当出土率小于或大于100%时及采用开口率较小的面板式刀盘时，盾构将产生不平衡掘进。大部分土压平衡盾构不平衡掘进产生挤土作用，造成正的地层损失及附加的应力场。试验结果表明，不平衡推进时挤土量一部分产生体积应变，一部分形成正的地层损失，使盾构前方地表产生了隆起；现场试验测试了刀盘前方附加应力场的大小和范围。研究成果可以指导土压平衡盾构推进时的参数控制，对控制推进时地表变形有指导意义。
关键词：土压平衡盾构；平衡控制；出土率；螺旋机；地层损失；附加应力

Theoretical and test studies on balance control of EPB shields

Wang Hongxin^1,2 Fu Deming²
(1. Tongji University, Shanghai 200092, China;
2. Shanghai Tunnel Engineering Co., Ltd., Shanghai 200082, China)

Abstract: EPB shields may be in two types of state of balance during tunneling, one being the balance between the contact pressure of shield and the front pressure of earth and water, and the other being the balance in the mucking earth. These two balance states are equivalent only when the head aperture ratio is sufficiently large. Because of cutter head compression, large deviation occurs when shield cutter head has small head aperture ratio. Mucking earth rate is an important index to the control of earth pressure balance. When the mucking earth rate is 100%, the balance state of mucking earth is reached. It is difficult to directly control mucking earth rate during tunneling, but it may be indirectly controlled through adjusting shield construction parameters. The relationship between mucking earth rate, rotation speed of screw conveyor and advance rate is derived, and later verified by using model test data. Based on model tests, a method for determining the above relationship of balance state is presented. When mucking earth rate is not equal to 100%, or for shields using skin-plate cutter head, shield advance is under unbalanced state. Unbalanced tunneling of most EPB shields would generate positive loss of soil and secondary stress. The test results indicate that squeezing of shield caused some volumetric strain and positive ground loss. In addition, the magnitude and range of secondary stress in front of cutter head were tested.
Keywords: EPB shield; balance control; mucking earth rate; screw conveyor; ground loss; secondary stress

E-mail: tjwanghongxin@sina.com

连拱隧道裂缝运动的监测与分析

王建秀¹ 朱合华¹ 唐益群¹ 周念清¹ 叶 冲¹ 陆永春²
（1.同济大学，上海200092；2.上海地矿建设有限责任公司，上海200072)

摘要：连拱隧道在修建以及运营过程中出现裂缝，会导致衬砌出现渗漏水，破坏结构的完整性、影响结构的耐久性，极端不利情况下甚至可能导致结构整体崩溃，危及隧道施工及运营的安全。开展裂缝运动特征的基础研究，进行大量现场监测并总结规律是可行的方法。典型连拱隧道30个裂缝测点的监测结果表明裂缝运动存在时效特征，先增后减的裂缝运动是一般规律，跳跃性突变及匀速单调发展的裂缝运动不是裂缝正常的运动范畴，必然是施工扰动或其他相关因素导致裂缝运动出现异常所致。裂缝的运动既有张开又有鼓出，通过多点张开及鼓出的联合测量，能够更好地了解裂缝运动的多点时空特征，可用于判定裂缝测点布置的代表性问题。双连拱隧道的施工工序远较分离式隧道复杂，通过裂缝运动的监测，可以了解隧道结构整体受力的健康情况，进而指导隧道的施工及防灾。
关键词：连拱隧道；裂缝运动；裂缝监测；工程应用

Monitoring and analysis for movement of cracks of twin-arch tunnel

Wang Jianxiu¹ Zhu hehua¹ Tang Yiqun¹ Zhou Nianqing¹ Ye Chong¹ Lu Yongchun²
（1.Tongji University，Shanghai 200092，China；
2.Shanghai Geological Construction Co., ltd., Shanghai 200072，China)

Abstract: Cracks of twin-arch tunnel in construction or in operation would cause leakage of lining, damage of structure and reduction of tunnel durability. Under extreme adverse conditions, tunnel structure might even be collapsed completely. It is essential to conduct basic study on crack movement for twin-arch tunnels, and in-situ monitoring is one of the feasible methods. The monitoring data of 30 cracks’movements in a typical twin-arch tunnel of the Yuanjiang-Mohei expressway in Yunnan province indicated that the width of cracks changed with time, with the general trend of increasing first and decreasing later, and any sudden change or monotonic increase in crack width is abnormal and must be caused by external disturbances. The crack movement for the twin-arch tunnel involves both opening and extruding, the time-dependent characteristics of which can be obtained by monitoring. For twin-arch tunnels, the construction course is more complicated than two separate tunnels, and crack monitoring may provide an efficient way to determine the health conditions of a tunnel.
Keywords: twin-arch tunnel; crack movement; crack monitoring

E-mail: wang_jianxiu@163.com

区域运输通道网络设计研究

赵 航 何世伟 宋　瑞
（北京交通大学，北京 100044）

摘要：运用离散优化方法，研究区域内各组团间运输通道网络优化设计问题，设定运输通道供给能力以及通道在区域之间的运输时间约束，构造综合运输通道投资建设总费用的优化模型，考虑各种运输通道的单位投资建设费用和建设长度的最优问题；利用综合运输通道的特点和区域组团网络结构进行算法设计，并给出最优解的多方案求解步骤；针对大规模节点采用遗传算法进行求解可以提高求解效率；通过一个算例，对模型和算法的可行性和有效性进行验证，说明该算法可得到综合运输通道的最优投资方案，使综合运输通道满足规划年的客货运需求，以及各种运输方式的平均出行时间满足要求，分析说明客货运输需求与运输通道建设的关系，结果表明提出的模型与算法对交通投资项目提供较好的辅助决策支持。
关键词：交通工程；综合运输；网络设计；运输通道；空间组团；遗传算法

Network design for regional transportation corridors

Zhao Hang He Shiwei　Ｓong Rui
(Beijing Jiaotong University, Beijing, 100044, China)

Abstract: Optimal network design for transportation corridors of regional space groups is studied by using combinatorial optimization. The optimal investment model of multimodal transportation corridors is formulated by establishing supply capacity constraint and travel time constraint of transportation corridors. The unit investment cost and the length of transportation corridors is synthetically considered in the model. A method is designed by considering the characteristics of multimodal transportation corridors and the network structure of regional groups, and computational schemes are provided. The efficiency of solution is improved by using a genetic algorithm for large number of nodes. The feasibility and effectiveness of the model and the algorithm is verified through examples, which indicate that the optimal investment scheme is identified to meet transportation demands for planning and the average travel time of each transportation mode. The relationship between transportation demands and transportation corridor design is analyzed, and the results indicate that the model and the solution could be a promising approach to improving the traffic investment programs.
Keywords: traffic engineering; multimodal transportation; network design; transportation corridor; space group; genetic algorithm

E-mail: wazua@163.com

我国政府投资项目管理的制度变迁

张 伟 朱宏亮
（清华大学，北京100084）

摘要：我国投入了大量财政资金进行基础设施建设，但政府投资项目管理中却存在比较严重的超支、质量和腐败问题，这与管理制度不健全有很大关系。我国政府投资项目管理模式随经济体制改革经历了一个复杂的变迁过程，可被分为三个阶段：在计划经济阶段主要采用自建模式、国有企业模式和工程指挥部模式，体制转轨阶段出现了项目法人制，市场经济初期出现了政府采购模式、代建制和私人融资模式。这些模式的运作机理各不相同，适用的项目类型和管理效果也有显著差异。对这些模式的比较分析表明，政府投资项目管理模式改革应遵循资金来源合理、政府职能合理、采购透明、节约管理成本、积累管理经验、制约腐败六项原则。随着市场经济体制的不断完善，应允许代建制、政府采购模式、私人融资模式、项目法人制等共存，并应根据项目具体情况合理选择管理模式。
关键词：政府投资项目；制度变迁；改革方向

Institutional transformation of government project management in China

Zhang Wei Zhu Hongliang
（Tsinghua University, Beijing 100084, China）

Abstract: The Chinese government has made heavy expenditure on infrastructure and other public works. However, the current performance of government projects is unsatisfying because of cost overrun, poor quality and corruption. As one of the significant reasons, the institutional arrangement of government project management is deficient and needs to be ameliorated. In this study, the institutional transformation process is divided to three phases. In the Planned-Economy Period, the Self-Building Method, the State-Owned Enterprise Method and the Project Headquarters Method were usually used in government project management; in the Systematic Transformation Period, the Project Cooperation Method was brought out; and in the Early Market Period, the Government Procurement Method, the Agent Construction Method and the Private Financing Method were innovated. Based on a comparison of these methods, six basic principles were refined for institutional amelioration of government project management, i.e., effective funding source, proper government function, procurement transparency, lower management cost, gathering management experience and restraining corruption. To improve the performance of government projects, different management methods should be rightfully chosen and related institutional arrangement should be ameliorated.
Keywords: government construction project; institutional transformation; reform direction

E-mail: zhang_wei98@mails.tsinghua.edu.cn

关于地源热泵发展的运行机制、管理模式和扩散模式的研究

张国东¹ 武 涌² 刘长滨³
（1.哈尔滨工业大学，黑龙江哈尔滨150001; 2.建设部科技司，北京 100835;
3.北京建筑工程学院，北京 100044）

摘要：在建筑领域规模化应用可再生能源是降低建筑能耗的重要途径之一。以地源热泵产业发展的运行机制和管理模式为研究对象，针对目前地源热泵系统在建筑中应用存在的成本高和市场规模小的问题，借鉴国外可再生能源发展的经验，分析促进其发展的目标机制和补偿机制，通过概算，预测符合国家可再生能源发展规划的地源热泵系统的发展目标，提出用于增量成本补偿的资金保障措施；探讨以政府主导为主、市场机制配合的管理模式，并对相关行政管理部门转变职能提出建议；探索具有中国特色的城市级示范的推广扩散模式。
关键词：地源热泵；运行机制；管理模式；扩散模式

A study on the operation mechanism, management mode and promotion
mode of ground-source heat pump development

Zhang Guodong¹ Wu Yong² Liu Changbin³
(1.Harbin Institute of Technology, Harbin 150001, China;2.Department of Science & Technology,
Ministry of Construction P.R.China, Beijing 100835, China; 3.Beijing Institute of Civil
Engineering & Architecture, Beijing 100044, China)

Abstract: Large-scale application of renewable energy in buildings is one of the important approaches to reducing the energy consumption of buildings. In order to study the operation mechanism and management mode of Ground-Source Heat Pump (GSHP) development, focusing on the issues of high cost and small market of the application of GSHP system to buildings, analyses are conducted on the target mechanism and compensation mechanism of promoting the development of GSHP system, based on experiences of utilizing renewable energy in developed countries. The development target of GSHP system is estimated in conformity with the national renewable energy development plan of China. The financing supportive measures of compensating the incremental costs are proposed. The management mode of governmental domination with market support is discussed and suggestions are provided on transforming functions of related administrative departments. The mode of city-level promotions in China is also explored.
Keywords: Ground-Source Heat Pump (GSHP); Operation mechanism; Management mode; Promotion mode

E-mail: zhangguodong@hit.edu.cn

基于移动控制力模型的轨道梁动力特性初步研究

时 瑾¹ 魏庆朝² 招 阳²
（1.同济大学，上海 200331；2.北京交通大学，北京 100044）

摘要：磁浮轨道梁动力特性是磁浮关键技术研究中的重要内容，该方面的研究一直以来备受结构工程界的关注。结合已有研究成果，建立了悬浮模块与轨道梁动力相互作用模型，考虑主动控制的电磁力特性，对一系列悬浮模块在轨道梁上移动引起的动力响应进行数值仿真计算，分析了轨道梁阻尼比、跨数、重量和列车运行速度对轨道梁变形特性的影响规律。分析结果表明：结构阻尼对梁系统动力特性影响较小；基频不变的条件下，简支梁质量变化对梁动力系数的影响很小；随着速度提高，冲击系数总体上呈波动上升趋势，但在正常运行速度下并未出现明显的共振现象。本文的研究结论为轨道梁合理设计参数的选取提供了理论依据。
关键词： 铁路运输；磁浮交通；轨道梁；动力响应，变形

Ａ study on the dynamic response of guideway girders under moving control force

Shi Jin¹ Wei Qingchao² Zhao Yang²
(1. Tongji University, Shanghai 200331, China;
2. Beijing Jiaotong University, Beijing 100044, China)

Abstract: As an important part of key technologies of maglev system, the dynamic response of guideway girders has attracted much attention from researchers in structural engineering. Based on available existing research results, a suspension magnet-guideway dynamic model is established, with the dynamic characteristics of magnet-rail relationship under active control considered. A numerical simulation is performed, using the model, to investigate the dynamic responses of the magnet and the guideway, and the effects of guideway girder parameters (e.g., damping ratio, number of spans and weight) and train velocity on the deformation of the girders are analyzed. The results indicate that damping ratio has little influence on the dynamic response of the system. If the basic frequencies of girders are similar, mass change has little influence on the dynamic coefficients of single span girders. The coefficient of impact follows a fluctuating ascending trend, but resonance vibration is not significant within the range of normal running speed.
Keywords: railway transport; maglev; guideway; dynamic response; deformation

E-mail: sjnjtu@163.com

柔性基层沥青路面结构黏弹性力学响应分析

赵延庆¹ 黄大喜² 潘友强¹
(1.江苏省交通科学研究院，江苏南京 210017;
2.内蒙古通辽市交通工程局，内蒙古通辽 028000）

摘要：沥青混合料是典型的黏弹性材料，只有对沥青路面结构进行黏弹性分析，才能得到其实际的力学响应。对一柔性基层沥青路面的各层沥青混合料进行了不同温度、不同频率下的复数模量试验，并利用黏弹性理论关系式，将沥青混合料复数模量试验结果转化为其蠕变柔量的Prony系列表达式，并进而求解在静载和加载、卸载两种荷载模式下路面结构路表弯沉、基层底面拉应变和土基顶面压应变的黏弹性力学响应。研究结果表明，由于沥青混合料的蠕变和松弛特性，各种响应尤其是基层底面的拉应变随时间呈现出较为复杂的变化趋势。随加载或卸载时间的延长，各响应逐渐趋于稳定。本研究也表明进行黏弹性分析可以更科学地描述沥青路面结构的行为特性及破坏原理。
关键词：黏弹性响应；复数模量；蠕变柔量；Prony系列；加载；卸载

Analysis of viscoelastic responses of asphalt pavements with flexible bases

Zhao Yanqing¹ Huang Daxi² Pan Youqiang¹
(1.Jiangsu Transportation Research Institute, Nanjing 210017, China；
2. Inner Mongolia Tongliao Municipal Transportation Bureau, Tongliao 028000, China)

Abstract: Asphalt mixtures are typical viscoelastic materials. Realistic responses of asphalt pavements can only be obtained by conducting viscoelastic analysis. In this study complex modulus tests were conducted for asphalt mixtures used in an asphalted expressway with a flexible base, and the test results were then converted to Prony series of creep compliances by using theoretical relationships. Surface deflection, tensile strain at the bottom of the base layer and compressive strain at the top of subgrade were calculated under constant loading and loading/unloading conditions by using viscoelasticity theories. The results indicate that the viscoelastic responses of pavements，especially the tensile strain at the bottom of the base layer, vary significantly with time due to the creep and relaxation characteristics of asphalt mixtures. The responses become stable after long period of loading or unloading.
Keywords: viscoelastic response; complex modulus; creep compliance; prony series; loading/unloading

E-mail: yzhao@ti.js.cn

全站仪竖直高程传递技术及其在苏通大桥测控中的应用

周建林¹ 岳东杰²
（1. 苏通大桥建设指挥部,江苏南通 226100；2. 河海大学, 江苏南京 210098）

摘要：高程基准传递是高大建筑物施工测控中重要项目之一，不同的工程因用途不同对高程控制提出不同的精度要求。针对苏通大桥高索塔施工中高程测控的要求，分析水准测量、钢尺高程传递、三角高程测量等常用高程传递技术的适用范围与缺点，它们均不适用于大高差的高精度传递。为此，提出全站仪竖直高程传递技术。详细论述其基本原理，对误差来源、大小进行分析，对所达到的精度进行评估，并研制传递高程的实用装置，经现场试验对比分析，验证该技术方法的可行性与有效性。理论分析与试验验证显示该技术方法对于数百米的高程传递，可以达到国家二等水准精度水平，完全满足建筑物高程测控的需要。最后将该技术成功应用在苏通大桥300 m高索塔的高程测控中。
关键词：高程传递；全站仪；误差分析；索塔施工；苏通大桥

Total station height transmission technology and its application in height
control of Sutong Bridge tower construction

Zhou Jianlin¹ Yue Dongjie²
（1.Sutong Bridge Construction Commanding Department, NanTong 226100，China;
2.Hohai University, NanJing 210098，China)

Abstract: Aiming at precision requirement of height control in tower construction of Sutong Bridge, Some commonly methods used height transmission are analyzed simply such as leveling measurement, steel tape method and trigonometric leveling measurement, they can not fit to large height transmission in high precision. Then the total station height transmission technology is proposed. The basic principle is demonstrated, the errors origin and size is analyzed and precision is estimated. According to the principle, an appropriate equipment is developed. Through the experiment and compare analysis, the feasibility and the validity of this technical method is proved. Principle analysis and experiment show that the precision of this technology can reach the precision of national second-class leveling, can meet the height precision of building construction. The technology has been applied in the tower construction surveying of Sutong Bridge.
Keywords: height transmission; total station; error analysis; tower construction; Sutong Bridge

E-mail: stbcd@stbridge.com.cn

上海地下工程建设中的经验和教训

白 云¹ 汤 竞²
（1.上海城建集团，上海 200023; 2.同济大学，上海 200092）

摘要：近年来，随着上海经济的发展以及2010年上海世界博览会的迫切需求，上海市掀起了基础设施建设（特别是地下工程建设）的新高潮。本文着重介绍了上海近几年来地下工程建设的现状和所取得的成就，这其中包括轨道交通工程、越江隧道工程、地下道路工程、地下市政工程以及地下空间规划利用等多方面的进展情况。同时结合笔者多年来的地下工程建设经验，对上海地下工程建设过程中存在的规划、建设以及管理等方面的问题和所得到的教训进行了总结。在此基础上笔者对上海地下工程今后的发展趋势进行了展望，认为今后地下工程将向深层次化、信息化、以及节能化等方向发展，并对今后地下工程的建设提出一些建议，希望加强今后地下空间的立法管理以及地下工程建设过程中的风险管理。
关键词：上海；地下工程；地下空间；隧道；基坑

Experience and lessons from underground construction in Shanghai

Bai Yun¹ Tang Jing²
(1.Shanghai Urban Construction Group, Shanghai 200023, China )
(2.Tongji University, Shanghai 200092, China )

Abstract: The underground construction in Shanghai has recently stepped into a new high, thanks to booming economy and EXPO 2010 Shanghai. The focus of the paper is on introducing the development and achievement of underground constructions in Shanghai, such as MRTs, road tunnels, and underground municipal works. Lessons learned from the underground constructions in Shanghai are summarized. Perspectives of future technical trend and some suggestions are also presented.
Keywords: Shanghai; underground space; tunnel; deep excavation; EXPO

E-mail： baiy@sucg.com.cn