2007年11月摘要
钢管节点性能化设计的研究现状与关键问题
王 伟1 陈以一1，2 赵宪忠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：钢管结构对大跨度公共建筑与中高层建筑来说是一种具有较强性能优势和广泛应用前景的结构形式。虽然钢管节点的静力与疲劳性能研究已经取得较多成果，但与大型结构工程实践提出的要求相比，仍存在许多不足。以性能化设计这一当代结构设计理念的发展趋势为背景，对国内外有关钢管节点力学性能的研究成果进行评述，指出目前主要的不足在于节点刚度评价准则的不完备、节点抗震与抗火性能研究的缺乏。在阐明基于结构整体行为的节点性能化设计概念的基础上，提出钢管节点性能化设计研究应该包括节点性能指标的确定和计算、节点分类准则的建立和考虑结构整体与局部相关性的设计方法的建立等内容。并进一步指出和探讨该研究领域需解决的若干关键技术问题。
关键词：钢管节点；性能化设计；非刚性性能；抗震性能；抗火性能；节点分类准则；节点与结构行为相关性
State of the art and key issues on performance-based design of steel tubular joints
Wang Wei1 Chen Yiyi1，2 Zhao Xianzhong1
（1.Tongji University, Shanghai 200092, China; 2.State Key Laboratory for Disaster Reduction in Civil Engineering, Tongji University, Shanghai 200092, China）
Abstract: Steel tubular structure has lots of advantages and is widely used for large span public structures and medium-to-high-rise buildings. Although significant progress has been made in the study of static and fatigue behavior of tubular joints, many deficiencies still exist if compared with the demands of engineering practices. State-of-the-art research on the mechanical behavior of tubular joints is reviewed, on the basis of Performance-Based Design philosophy. Studies on the criterion of rigidity estimation, earthquake and fire resistant performance of tubular joints are found to be insufficient. A concept of performance-based connection design by considering global structural response is described. Further study should include the determination and computation of indexes representing the joint behavior, the establishment of classification criteria for tubular joints and the foundation of design method considering global and local structural interactions. Several key issues are also identified and discussed.
Keywords: steel tubular joint；performance-based design；non-rigid behavior；seismic behavior；fire resistant behavior；joint classification；interaction between connection and structural behavior
E-mail: weiwang@mail.tongji.edu.cn
变电构架柱的节点试验研究与有限元分析
朱爱珠1 郭耀杰2 程 超3 胡小龙3
（1.华中科技大学，湖北武汉430074；2. 武汉大学，湖北武汉430072；
3.中南电力设计院，湖北武汉430071）
摘要：提出变电构架柱新型螺栓连接柱头形式，通过试验研究和有限元计算相结合的方法，验证新型构架柱的可行性。首先，以有限元分析为基础，选取2.5 m构架柱柱头节点作为试验研究对象，分析盖板螺栓数量和竖板厚度变化对节点刚度和强度的影响；其次，结合试件底部位移实测数据对2.5 m节点进行计算，并将结果与实测结果比较，验证了模型计算的可行性；最后，对多种28 m构架柱进行计算，比较分析柱顶挠度和控制点Von-Mises应力，得出节点试件所对应的新型构架柱基本满足工程设计的强度和刚度要求，且与增加盖板螺栓相比，增大竖板厚度是提高构架柱刚度和强度较为有效可行的方法。
关键词：新型节点；螺栓连接；试验研究；A形构架柱；有限元
Experimental study and finite element analysis on the joint of power transformation truss-column
Zhu Aizhu1 Guo Yaojie2 Cheng Chao3 Hu Xiaolong3
（1.Huazhong University of Science and Technology, Wuhan 430074, China;
2.Wuhan University,Wuhan 430072, China;
3.Central Southern China Electric Power Design Institute, Wuhan 430071, China）
Abstract: A new type of bolting top-joint for power transformation truss-column was proposed. Experimental study and finite element calculation were used to validate the feasibility of the new type of truss-column. In order to study the influences of the number of bolts in the cover plate and the thickness of the vertical plate on the top-joint's rigidity and strength, 2.5 m-heigh top-joints were tested, based on the finite element analysis. These 2.5 m joints were also calculated by using the measured bottom displacement. Comparing the calculation results with the test results, the feasibility of the finite element calculation method was validated. Several truss-columns of a height of 28 m were also calculated, and the top deflection of the column and the Von-Mises stress of the key-point in the tubes were analyzed. The conclusion is that all truss-columns with the new top-joints basically satisfy the rigidity and strength demands. Furthermore, in order to improve the rigidity and strength of the bolting truss-column, increasing thickness of the vertical plate is more effective and feasible than increasing the number of bolts in the cover plate.
Keywords: new joint type; bolting; experimental study; A-shaped power transformation truss-column; finite element
E-mail: zhuaizhu1228@163.com
钢纤维高强混凝土连梁抗剪试验研究
张宏战1，2 张瑞瑾3 黄承逵1，2
（1.大连理工大学海岸和近海工程国家重点实验室，辽宁大连116024；
2.大连理工大学，辽宁大连116024；3.大连水产学院，辽宁大连 116023）
摘要：为了改善平行配置纵向受力钢筋和横向箍筋的高强混凝土连梁的抗剪性能，进行9根小跨高比钢纤维高强混凝土连梁（l/h≤2.5）和4根高强混凝土连梁的对比试验。考察了跨高比l/h、钢纤维体积掺率ρf、配箍率ρsv和加载方式对高强混凝土连梁的破坏形态和受剪承载力的影响。结果表明，以适量的钢纤维替代高强混凝土连梁中的部分箍筋，不仅可以提高连梁的受剪承载力，有效地防止混凝土保护层、斜裂缝面上和剪压区混凝土的酥裂和剥落，还能实现小跨高比高强混凝土连梁的破坏形态从脆性的剪切破坏到延性的弯曲破坏的转化。参照《纤维混凝土结构技术规程》CECS 38: 2004中钢纤维混凝土箍筋梁受剪承载力的计算模式，给出低周反复荷载作用下（l/h≤2.5）和静载作用下的钢纤维混凝土连梁受剪承载力计算公式。
关键词：钢纤维高强混凝土；连梁；破坏形态；受剪承载力
Experimental study of shear resistance of steel fiber reinforced
high-strength concrete coupling beams
Zhang Hongzhan1,2 Zhang Ruijin3 Huang Chengkui1,2
（1.State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China;2.Dalian University of Technology, Dalian 116024, China; 3.Dalian Fisheries University, Dalian 116023, China）
Abstract: To improve the shear resistance of high-strength concrete coupling beams with longitudinal and transverse reinforcements, a series of comparison tests is conducted with 9 steel fiber reinforced high-strength concrete coupling beams（l/h≤2.5）and 4 high-strength concrete coupling beams. The effects of span/depth l/h, steel fiber volume fraction ρf, stirrup content ρsv and loading modes on failure types and shear resistance capacity of coupling beams are investigated. The test results indicate that the partial replacement of stirrups by steel fibers can improve the shear resistance capacity of the coupling beams, eliminate the crumbling and spalling of the concrete cover and the concrete near diagonal cracks and in the compression-shear region of the coupling beams, and even bring out change in the failure type of coupling beams from brittle shear failure to? ductile flexural failure. According to the analytical model for steel fiber reinforced concrete beams in Technical Specification for Fiber Reinforced Concrete Structures（CECS 38: 2004）, some empirical formulas are presented to predict the shear resistance capacity of steel fiber reinforced concrete coupling beams.
Keywords: steel fiber reinforced high-strength concrete; coupling beam; failure type; shear resistance capacity
E-mail: hongzhan@student.dlut.edu.cn
CFRP钢管混凝土轴压长柱试验研究
顾 威1 赵颖华2
（1.辽宁省交通高等专科学校，辽宁沈阳110122；2.大连海事大学，辽宁大连116026）
摘要：通过18根CFRP钢管混凝土轴压柱和用于对比的6根钢管混凝土轴压柱的承载力试验研究，初步探讨CFRP钢管混凝土轴压柱的受力性能以及CFRP对钢管混凝土轴压柱承载力的提高效果。分析了CFRP约束效应系数和长细比对CFRP钢管混凝土轴压柱承载力的影响。研究结果表明：在本次试验的参数范围内，CFRP可以有效提高钢管混凝土轴压柱的承载力；CFRP对钢管混凝土轴压柱承载力的抬高率近似随着CFRP约束效应系数的增加而增加、随着长细比的增加而减小，当长细比达到某一定值时，提高率为零。并根据试验所得到的长细比影响折减系数引入钢管混凝土的长细比影响折减系数，确定了CFRP钢管混凝土轴压柱承载力的计算方法，与试验结果比较吻合良好。
关键词： CFRP；轴压柱；钢管混凝土；约束系数
Experimental study on concrete filled CFRP-steel tube columns with axial compression
Gu Wei1 Zhao Yinghua2
（1.Liaoning Provincial College of Communication, Shenyang 110122, China;
2.Dalian Maritime University, Dalian 116026, China）
Abstract: This paper presents an experimental work for concrete filled CFRP steel tubes subjected to concentrically axial compression. The mechanical properties and the increment ratio of load bearing capacity of the concentrically compressed concrete filled steel tube columns due to CFRP are studied. The test specimens include 16 concentrically compressed concrete filled CFRP-steel tube columns and 8 concrete tube columns without CFRP. Influences of the CFRP confinement index and the slenderness radio on the load bearing capacity of the concentrically compressed concrete filled CFRP-steel tube columns are analyzed. It is found: within the scope of the test, CFRP would enhance the load bearing capacity of the concentrically compressed concrete filled tube columns effectively; the increment ratio of load bearing capacity due to CFRP increases with the increment of CFRP tube confinement index and decreases with the increment of slenderness ratio. A slenderness ratio index is also presented, capable of predicting the axial load strength of concrete filled CFRP steel tube members. Experimental results are in good agreement with the predicted values.
Keywords: CFRP; axial compressive column; concrete filled steel tube; confining index
E-mail: guwei01977@sina.com
考虑结构局部反应特征的时程分析法输入地震波研究
杨 红 吴晶晶
（重庆大学， 重庆400045）
摘要：时程分析法在实用中多采用“3+1”的小样本容量地震波输入方式，该选波方案一般依据基底剪力、顶点位移等结构整体反应指标而取得。为提高时程分析法对构件局部地震变形需求的控制能力，以按我国规范设计的典型钢筋混凝土框架为算例， 在OpenSees分析平台上，分别进行了30条地震波的大样本和以“3+1”选波方案为例的小样本地震波在罕遇烈度下的非线性时程反应分析。在对地震反应进行统计回归分析后，将小样本分析所得各反应量的均值、均值加1倍标准差等统计特征值与大样本统计结果进行比较，着重考察框架的塑性铰分布、构件转角延性等局部反应。研究结果表明，“3+1”分析方法所得的框架整体变形能较好地与大样本分析结果相符，但多数构件端部转角延性的“3+1”分析均值偏小，建议增加小样本分析的地震波数量。
关键词：钢筋混凝土；局部反应；地震波；非线性反应；时程分析
A Study on the earthquake input for time-history analysis based
on the local response characteristics of structures
Yang Hong Wu Jingjing
（Chongqing University, Chongqing 400045, China）
Abstract:‘3+1’is the mall sample size of earthquake wave input method commonly adopted in practical time-history analysis. It is generally obtained base on the global structural responses, such as base shear and top displacement. The capability of time-history analysis for controlling the local structural seismic responses is studied. A typical reinforced concrete frame designed according to the Chinese building codes is chosen as the example. Based on the OpenSees framework, a series of nonlinear time-history analyses under a large sample of thirty rare earthquake waves and a small sample of“3+1”rare earthquake waves are performed, respectively. Through the statistical calculation of seismic responses, the statistical characteristics, such as mean value and mean plus standard deviation, obtained from the“3+1”analysis are compared with the corresponding values from the large sample analysis. Local responses of the frame, namely the plastic hinge distribution and the rotation ductility of beams and columns, are analyzed. The results indicate that the global response from the“3+1”analysis matches well with the corresponding results of the large sample analysis, while most of the mean rotation ductility of members from the“3+1”method are smaller, and it is suggested that sample size should be increased.
Keywords: reinforced concrete; local response; earthquake wave; nonlinear response; time-history analysis
E-mail: yangh@cqu.edu.cn
拉压杆模型方法在钢筋混凝土框架节点计算中的应用研究
王田友1 苏小卒1 方江生2
（1.同济大学，上海200092；2.中信建设集团，北京100004）
摘要：目前钢筋混凝土框架节点设计主要是依据各种构造要求，在很多情况下缺乏计算节点的承载力的方法。拉压杆模型方法是一种基于塑性理论的下限方法，可以考虑结构中的剪切作用的影响。对四种典型框架节点建立了拉压杆模型，拉压杆模型的计算结果与相应的框架节点试验结果符合较好。同时还提出与节点区的拉压杆模型对应的外力确定的简明方法。分析表明，在梁和柱中的拉杆与压杆强度足够和纵筋伸入节点核心区足够深且安全锚固的情况下，框架节点拉压杆模型的控制杆件是节点核心区的主斜压杆。因此，基于已有节点试验数据提出一种主斜压杆的验算方法。提出的钢筋混凝土框架节点的拉压杆模型可以拓展到整个框架或与现有的框架计算方法相结合，实现包括节点在内的全框架承载力计算。
关键词：钢筋混凝土框架；节点；拉压杆模型；主斜压杆；结点
Application of STMs for calculation of reinforced concrete frame joints
Wang Tianyou1 Su Xiaozu1 Fang Jiangsheng２
（1.Tongji University, Shanghai 200092, China;
2.CITIC Construction Group, Beijing 100004, China）
Abstract: The present methods for designing reinforced concrete frame joints are mainly based on composition requirements, lacking a method for calculating the strength of joints. The strut-and-tie model（STM）method, a lower-bound method based on theory of plasticity, is suitable for considering the influence of shear in structures. The STMs for four representative frame joints are established. The results from the STMs agree well with the corresponding test data. A method to determine the external force corresponding with STMs in joint region is presented. The analysis indicates that the critical members of the STMs are the main diagonal struts in the joint core region if struts and ties in beams and columns are safe and ties of the members are extended adequately into the joint core region and safely anchored. Therefore, a method for calculating the main diagonal struts is presented based on test data. The presented STMs of frame joints can be extended to the whole plane frame to obtain a unified STM or they can be associated with the existing frame design method, so that the strength of the entire frame including its joints can be checked.
Keywords: R C frame; joints; strut-and-tie model; main diagonal strut; node
E-mail: wtytj_2001@163.com
外包钢-混凝土组合梁与钢筋混凝土柱节点的试验研究
陈丽华1，2 李爱群2 鲁风勇2 娄 宇3 李培彬3
（1.合肥工业大学，安徽合肥230009；2.东南大学，江苏南京210096；
3.中国电子工程设计院，北京100840）
摘要：外包钢-混凝土组合梁是一种新型组合梁，在负弯矩作用下具有良好的工作性能，其与柱连接节点的构造还有待合理设计并试验验证。采用两种不同的构造形式，设计4个外包钢-混凝土组合梁与钢筋混凝土柱的连接节点，并对其进行低周反复荷载作用下的试验研究。对节点的破坏形态、滞回曲线、强度、延性和钢筋、钢板的应变等性能进行分析，结果表明：通过合理的构造措施，外包钢-混凝土组合梁与钢筋混凝土柱的连接节点具有较好的受剪承载力、延性和耗能能力，能够满足工程要求。在此基础上对节点的受力机理进行探讨，提出节点核心区受剪承载力的计算公式，计算结果和试验结果吻合良好。
关键词：外包钢-混凝土组合梁；钢筋混凝土柱；节点；受剪承载力；延性；耗能能力
Experimental study on joints of outer-plated steel-concrete
composite beam and reinforced concrete columns
Chen Lihua1，2 Li Aiqun2 Lu Fengyong2?? Lou Yu3 Li Peibin3
（1.Hefei University of Technology, Hefei 230009, China; 2.Southeast University, Nanjing 210096, China;3.China Electronics Engineering Design Institute, Beijing 100840, China)
Abstract: Outer-plated steel-concrete composite beam is a new type of composite beam, its rational design and experimental verification are needed for the construction of the joints connecting the beam with the columns. For two types of structural forms, four joints connecting the outer-plated steel-concrete composite beam with reinforced concrete columns are designed and investigated by using low-cyclic load tests. The characteristics of joints, such as failure mode, hysteretic curve, strength, ductility, and strain of steel bars and plates, are analyzed. The experimental results indicate that significant shear-resistant capacity, satisfactory ductility and energy-dissipation ability can be obtained by appropriate constructional measures. The mechanical mechanism of the joint is further investigated and a formula is presented for calculating the shear capacity of the joint in its core area. The computational solutions agree well with the experimental results.
Keywords: outer-plated steel-concrete composite beam; reinforced concrete column; joint; shear-resistant capacity; ductility; energy-dissipation ability
E-mail：hfclh1997@126.com
体外索钢箱-混凝土组合连续梁非线性结构性能试验研究
张 南1 周 奇1 洪英维2
（1.南京工业大学，江苏南京210009；2.江西省交通设计院，江西南昌330002）
摘要：钢箱-混凝土组合连续梁负弯矩区混凝土的开裂问题影响了这类组合结构向更大跨度的发展。针对这一问题，提出在钢箱-混凝土组合连续梁中施加体外索的新技术，研究施加体外索对增强钢箱-混凝土组合连续梁负弯矩区混凝土的抗裂能力，提高钢箱-混凝土组合连续梁弹塑性结构性能的有利作用。经对比试验表明，施加体外索后，钢箱-混凝土组合连续梁负弯矩区混凝土的开裂荷载提高2.8倍，组合连续梁的弹塑性抗弯刚度提高29.35%，承载力提高34.67%，结构性能显著提高。在试验研究基础上，分析钢箱-混凝土组合连续梁负弯矩区局部力学性能与整体非线性结构性能的关系，揭示体外索提高钢箱-混凝土组合连续梁弹塑性结构性能的力学实质，给出承载力计算建议。研究结果可作为体外索钢箱-混凝土组合连续梁工程应用和理论分析的参考。
关键词：体外索；钢箱-混凝土组合连续梁；非线性结构性能
Experimental study on the nonlinear structural performance of steel-concrete
composite continuous box beams with external tendons
Zhang Nan1 Zhou Qi1 Hong Yingwei2
（1.Nanjing University of Technology, Nanjing 210009, China;
2.Communication Design Institute of Jiangxi Province, Nanchang 330002, China）
Abstract: Cracking of concrete flange slab in the negative moment area in steel-concrete composite continuous box beams affects its application for longer spans. A new technique of using external tendons in steel-concrete composite continuous box beams is proposed. As studies indicate， the external tendons may improve the crack resistance ability of concrete flange slab in the negative moment area and the elastoplastic structural performance of steel-concrete composite continuous box beams. Comparison with the experiments proves that the crack load， the elastoplastic stiffness and the load carrying capacity of steel-concrete composite continuous box beams are increased by 280%， 29.35 % and 34.67 %， respectively. Based on the experimental results， the relationship between the local mechanical performance in the negative moment area and the nonlinear structural performance of steel-concrete composite continuous box beam is analyzed. The mechanical essence that the external tendons may improve the elastoplastic performance of steel-concrete composite continuous box beams is explained. The calculation formulas of load carrying capacity are suggested.??
Keywords: external tendon; steel-concrete composite continuous box beam; nonlinear structural performance
E-mail: jiaodazhang@126.com
贝壳形钢屋盖大悬挑结构的有限元验算分析
周继忠1 张士元1 蔡雪峰1 郑百林2 林惠忠3
（1.福建工程学院，福建福州350007；2.同济大学，上海200092；
3.福建省第五建筑工程公司，福建泉州362000）
摘要：某市重点工程贝壳形钢箱梁屋盖大悬挑结构工程，在施工安装后拆除临时支撑过程中，发现大悬挑钢箱梁结构变形过大，其值超过钢结构规范规定。为找出悬挑结构变形过大的原因和解决结构安全问题，对钢箱梁大悬挑结构原设计进行有限元方法分析。分析结果表明原设计钢箱梁大悬挑结构刚度存在不足，通过对有限元方法模拟计算结果的进一步分析，找出影响悬挑结构整体刚度的具体构件。在实际验证的基础上，结合工程实际情况，提出几种处理改进方案，并对各方案进行分析比较，选择最佳处理方案，减少经济损失，确保结构安全可靠。
关键词：钢结构；贝壳形；悬挑结构；有限元
Finite element analysis of shell-type steel roof cantilever structures
Zhou Jizhong1 Zhang Shiyuan1 Cai Xuefeng1 Zheng Bailin2 Lin Huizhong3
(1．FuJian University of Technology, Fuzhou 350007, China; 2.Tongji University, Shanghai 200092, China;3.Fujian No.5 Construction Engineering Corporation, Quanzhou 362000, China)
Abstract: Due to mistakes involved in the design of a shell-type steel roof construction for an important project, the displacement in the cantilever box steel beam was found to be excessively large. In order to study the reason for such excessive displacement and find a solution method, the structure was analyzed by using the finite element method. The analysis indicated that the rigidity of the cantilever box steel beam was deficient. Based on the construction situation, some treatment options were suggested, and a comparative analysis was conducted to identify the optimal measure so as to decrease the economic loss and to guarantee the structure reliability.
Keywords: steel structure；shell type；cantilever structure；finite element
E-mail: zjz0591@163.com
普通硅酸盐混凝土中临界氯离子浓度的试验研究
宋晓冰 孔启明 刘西拉
（上海交通大学，上海200240）
摘要：为得到含氯环境下普通硅酸盐混凝土中钢筋的开始腐蚀时间，首先应掌握的一个重要参数是临界氯离子浓度，此参数因受多种因素影响而数值分布较广。本文基于在脱钝过程中钢筋腐蚀电位集中体现了多因素的综合作用的观点，通过以下三部分工作对临界氯离子浓度进行了研究：首先，利用静电位法，在模拟溶液中测试了氯离子浓度与点蚀电位之间的关系，电位的变化范围取-350 ~ +100 mV（SCE）；然后，将钢筋混凝土试块放置在三种典型环境中（干燥、湿润、浸润环境），分别测试了三种环境下钢筋腐蚀电位的分布范围；最后，基于钢筋脱钝的两个必要条件：足够小的混凝土电阻以及腐蚀电位超越点蚀电位，得到针对三种腐蚀环境的以占水泥用量比例表示的总氯离子浓度取值。
关键词：钢筋腐蚀；临界氯离子浓度；点蚀电位；腐蚀电位
Experimental study on chloride threshold levels in OPC
Song Xiaobing Kong Qiming Liu Xila
（Shanghai Jiao Tong University, Shanghai 200240, China）
Abstract: In order to predict the time of corrosion initiation of reinforcement in concrete under chloride-containing environment, one of the most important parameters is the critical chloride threshold level, which is influenced by many factors. The present work is based on the idea that the corrosion potential of the reinforcement may include the contribution of the different parameters involved in depassivation. First, potentiostatic tests were performed on reinforcement submerged in simulated pore liquid with the range of potentials from -350 to +100 mV（SCE）, to obtain the relationship between chloride contents and pitting potential. Second, reinforced concrete specimens were placed in three typical environments, namely dry, saturated and submerged environments, and the corrosion potential distribution of reinforcement under different environments was investigated. Third, based on the two necessary conditions for corrosion initiation, i.e., sufficiently low concrete resistance and corrosion potential exceeding the pitting potential, the total chloride contents relative to the weight of cement were provided corresponding to the three typical environments.
Keywords: reinforcement corrosion; chloride threshold value; pitting potential; corrosion potential
E-mail: xbsong@sjtu.edu.cn
基于区间组合法的边坡稳定非概率模糊可靠性分析方法
曹文贵 张永杰
（湖南大学，湖南长沙410082）
摘要：根据边坡稳定性影响因素的随机性、模糊性以及岩土材料力学参数取值的区间性特征，采用非对称三角模糊数表示岩土力学参数取值可能性分布，并对试验数据进行区间模糊优化分析。将所得非对称三角模糊数转化成区间数，运用边坡稳定性分析的简化Bishop法与区间组合法建立边坡安全系数区间值及可能滑动面求解方法，避免了区间函数运算的区间扩张问题。将安全系数区间计算函数与给定安全系数值之差作为功能函数，利用非概率模糊可靠性分析方法计算不同截集水平下的模糊可靠性指标，进而得到其可能性分布曲线，并由可能性理论求得边坡失效可能度，从而建立了基于区间组合法的边坡稳定非概率模糊可靠性分析方法。工程算例表明，该方法具有一定的合理性，为边坡工程稳定性评价提供了新的途径。
关键词：边坡；区间性；模糊性；区间组合法；非概率模糊可靠性
Non-probabilistic fuzzy reliability analysis of slope stability based
on interval interconnection method
Cao Wengui Zhang Yongjie
（Hunan University, Changsha 410082, China）
Abstract: The factors of slope stability involve randomness and fuzziness, and the mechanical parameter values of rock and soil are usually given in intervals. Asymmetric triangular fuzzy numbers were used to describe the probability distributions, and interval fuzzy optimization analysis of test data was carried out to determine their values. These asymmetry triangular fuzzy numbers were changed into interval numbers. The calculating method for safety factor interval and possible slope failure surface was proposed by using a simplified Bishop's method and an interval interconnection method, avoiding the need for interval extension. The difference between the safety factor interval function and the given safety factor was regarded as the reliability function. Non-probabilistic fuzzy reliability analysis method was used to calculate the fuzzy reliability indexes with different cut-levels and the probable distribution curves. The possibility theory was introduced to obtain the slop failure possibility. Method for non-probabilistic fuzzy reliability analysis of slope stability based on interval interconnection was established. A practical example indicates the feasibility of the method, and it provides an approach for slop stability evaluation.
Keywords: slope；interval feature；fuzziness；method of interval interconnection analysis；non-probabilistic fuzzy reliability
E-mail: cwglyp@public.cs.hn.cn
降雨蒸发条件下膨胀土边坡的变形特征研究
陈建斌1 孔令伟1 郭爱国1 赵艳林2，3 吕海波2
（1.中国科学院武汉岩土力学研究所，湖北武汉430071;
2.广西大学，广西南宁530004；3.桂林工学院，广西桂林541004）
摘要：在典型膨胀土广泛分布的广西南宁地区建立缓坡、陡坡与坡面种草3种类型膨胀土边坡的原位监测系统，采用6参数小型气象站、测斜管和沉降板，跟踪测试边坡变形随气候变化的演化规律，揭示在降雨蒸发下膨胀土边坡的变形特征。认为降雨是导致膨胀土边坡变形最直接的气候因素，而蒸发效应是边坡变形破坏的重要前提之一；蒸发效应所产生的土体裂隙，使得吸湿条件下原位双环渗透试验获得的膨胀土水力特性具有与传统的非饱和土力学中的定义有相反的趋势，这也是膨胀土边坡在降雨入渗时发生变形乃至破坏的内在机制之一；通过对现场试验数据的拟合，建立了符合膨胀土边坡变形的经验性预测模型，其中边坡变形与土表净入渗量呈二次函数关系。
关键词：膨胀土边坡； 变形特征； 变形预测模型；降雨； 蒸发
Deformation characteristics of expansive soil slopes under
precipitation and evaporation
Chen Jianbin1 Kong Lingwei1 Guo Aiguo1 Zhao Yanlin2，3 Lü Haibo2
（1.Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China;
2.Guangxi University, Nanning 530004, China;
3.Guilin University of Technology, Guilin 541004, China）
Abstract: A field monitoring system is set up to measure three types of expansive soil slopes， i.e. gentle slope， steep slope， and slope planted with grasses， in Nanning， Guangxi province， where expansive soils are extensive. Variations of the deformations of these three types of slopes with the climate are measured by a six-parameter mini-meteorological station， inclinometers and settlement plates， to reveal the evolutions of deformation characteristics， in which precipitation is regarded as the most direct factor and evaporation effect is an important precondition. Cracks due to evaporation make the hydraulic properties of the expansive soils obtained through in-situ double ring infiltrometer test have a wetting trend opposite to the traditional definition in unsaturated soil mechanics， which is also an important mechanism. Based on fitting the in-situ measured data， an empirical prediction model for the deformation of expansive soil slopes is established， in which the relationship between slope deformation and net infiltration of the soil surface is quadratic.
Keywords: expansive soil slope; deformation characteristics; prediction model of deformation; precipitation; evaporation
E-mail: c1j2b3@tom.com
考虑施工过程的土钉支护土钉轴力计算及影响参数分析
郭红仙 宋二祥 陈肇元
（清华大学，北京100084）
摘要：结合土钉支护边开挖边支护的特点，分析土钉支护施工中的开挖效应，阐述讨论土钉力增量的变化对土钉支护施工过程分析的意义。定义开挖影响面为施工过程中土体开挖时边坡内部土体滑动趋势最明显且土钉轴力增加最多的面，定义开挖土压力为以开挖影响面为边界的土块体作用在土钉支护上且由土钉承担的力，建立以开挖影响面及其上土钉力增量为主要研究对象的施工阶段土钉支护分析模型，给出施工过程中土钉轴力的计算方法。与应用其他方法计算得到的Clouterre项目1号墙建造过程中土钉力及量测值进行比较，计算结果与量测结果吻合较好。此外，利用该方法对土性、基坑剖面几何形状和土钉设置等影响因素进行分析。分析表明，所提方法符合施工过程中土钉受力的变化规律，是一种可行的、实用的土钉轴力分析方法。
关键词：土钉支护；施工阶段；土钉轴力；开挖影响面
Analysis of the axial forces of soil nails during construction
Guo Hongxian Song Erxiang Chen Zhaoyuan
（Tsinghua University, Beijing100084, China）
Abstract: The excavation effects of soil nailing are analyzed by considering its construction feature — excavation and support alternatively. The role of incremental nail forces in the analysis of the construction process is addressed. The Excavation Influential Surface（EIS）is defined as the most likely slip surface intersecting the nails at the places where the incremental tensile forces of nails are maxima， provided that the latest stage of excavation surface remains temporarily unsupported and the new row of nails is not yet installed. The earth pressure due to the soil wedge separated by the EIS from the main body is defined as Excavation Earth Pressure （EEP）， and assigned to all nails. Incorporating EIS and soil nail incremental forces， a new phenomenological model is formulated for the analysis of soil nailing. The core of the model is to determine the EIS and the nail incremental forces at the intersecting points of EIS and the nails. Based on this model， calculation methods for the nail tensile forces are presented. The measured nail forces of Experiment 1（Clouterre Program）are compared with the calculation results obtained by the proposed method and others. Finally，the influences of soil parameters，the soil nailing profile and nail arrangements on the nail forces are discussed. Analyses indicate good agreement between the model predictions and the observations.
Keywords: soil nailing; construction phases; soil nail tensile force; excavation influential surface
E-mail: guohx@tsinghua.edu.cn
地铁振动荷载作用下隧道周围饱和软黏土分形研究
唐益群1，3 张 曦4 赵书凯2 王建秀1，3 周念清1，3
（1.同济大学岩土及地下工程教育部重点实验室，上海200092；2.同济大学地下建筑与工程系，上海200092；3.教育部城市环境与可持续发展联合研究中心，上海200092；4.中交上海三航科学研究院有限公司，上海200092）
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，在现场监测和室内GDS（多功能循环三轴试验系统）试验的基础上，利用压汞仪微观试验研究方法，对隧道周围饱和软黏土微结构进行定量研究。研究结果表明，孔隙分形维数在隧道不同深度处的变化规律可以用不同的循环应力比CSR来体现。随着深度的增加，循环应力比CSR也随之增大，分形维数随着循环应力比CSR的增加先是下降然后又逐渐上升。研究成果为软土地区饱和软黏土中地铁隧道轴线变形和隧道经过区域地面沉降作了有价值的探索，也为探讨地铁行车荷载作用下饱和软黏土的破坏机制、造成地铁隧道轴线变形与地面沉降研究提供一定的理论支持。
关键词：隧道工程；振动荷载；饱和软黏土；压汞试验；分形维数
A study on the fractals of saturated soft clay surrounding subway
tunnels under dyanmic loads
Tang Yiqun1，3 Zhang Xi4 Zhao Shukai2 Wang Jianxiu1，3 Zhou Nianqing1，3
（1.Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education, Tongji University， Shanghai 200092, China; 2.Department of Geotechnical Engineering, Tongji University, Shanghai 200092, China；3.United Research Center for Urban Environment and Sustainable Development, the Ministry of Education,Shanghai 200092, China; 4.Shanghai third harbour engineering science & technology research institute Co.,LTD.,Shanghai 200092, China）
Abstract: The saturated soft clay around the tunnel section from Jing’an Temple Station to Jiangsu Station of the Shanghai No.2 subway line is studied. With field observation and laboratory GDS and mercury intrusion porosimetry， a quantitative study is conducted on the microstructure of the saturated soft clay. The study reveals that the fractal dimension at a given depth may be embodied by the corresponding CSR. With the increase in depth，the CSR increases correspondingly，and the fractal dimension first increases and later decreases. This study is valuable for the subway axial deformation and for the ground settlement in the saturated soft clay，and prvodes theoretical support for damage mechanics，subway axial deformation and ground settlement under subway vibration load.
Keywords: tunnel engineering；vibrating load；saturated soft clay；mercury intrusion porosimetry；fractal dimension
E-mail: tangyiqun2@mail.tongji.edu.cn
盾构机实时姿态测量和计算方法的研究
唐争气1，2 赵俊三3 彭国新4
（1．中南大学，湖南长沙410083；2.湖南城市学院，湖南益阳413000；
3.昆明理工大学，云南昆明650093；4.广州地铁设计研究院，广东广州510000）
摘要：介绍盾构机（TBM）姿态的描述方式以及盾构机姿态测量原理与方法。结合自动化测量机器人的功能，提出基于测量机器人对盾构体（前体）上两点进行三维坐标测量；根据安装在盾构机机体上纵、横两个精密测倾仪，实时采集的盾构机俯仰角、滚动角，来确定盾构机的实时空间位置和水平方向的偏航角的方法；根据3个欧拉角描述姿态测量的原理，推导出其姿态计算方法，并给出姿态计算的程序实现流程。对全站仪采集的坐标测量点和盾构机的基准点的测量精度进行了分析。广州地铁4号线大学城段的测试实验结果与SLS-T激光自动导向系统的计算结果吻合，结果表明，两基准点的计算精度完全满足实际工程的精度要求，误差比规范要求要小。
关键词：欧拉角；姿态测量；全站仪；精度分析
Measurement and calculation method for real-time attitude of
tunnel boring machine
Tang Zhengqi1,2 Zhao Junsan3 Peng Guoxin4
（1.Central South University, Changsha 410083, China; 2.Hunan City University, Yiyang 413000, China；3.Kunming University of Science and Technology, Kunming 650093, China;4.The Guangzhou Institute of Subway Design, Guangzhou 510000, China）
Abstract: The description of the attitude of Tunnel Boring Machine（TBM）and the principle and method of measurement were introduced. Combining automation survey robot’s functions, the method to establish the spatial position and horizontal yaw of TBM were provided, dependent on the 3-D coordinates of two points of the TBM（front body）and the two angles, roll and pitch collected real-time by electronic double-axis inclination sensors. The formula for calculating the attitude, based on three Euler angles, was induced. The analysis was conducted for the accuracy of the survey on the two basis-points of TBM and the data collected by total station theodolite. Tests on the City University section of the Guangzhou Metro Line 4 were conducted, and the results are consistent with those from SLS-T（laser automatic guidance system）calculations. The calculation accuracy of completely satisfied the requirement of the project.
Keywords: Euler angle; attitude surveying; total station theodolite; precision analysis
E-mail: tzq_111@163.com
直线电机轨道交通系统土建工程与资源节约
孔令洋 梁青槐
（北京交通大学城市轨道交通研究中心，北京100044）
摘要：我国正处在城市轨道交通建设的高潮期。然而，在城市建成区建设城市轨道交通系统的难度越来越大，工程风险和工程造价都很高。采用直线感应电机驱动的直线电机轨道交通系统具有车辆断面小、轴重轻、动力性能好、爬坡能力强、曲线半径小、噪声低、振动小、养护维修少等优点。本文结合直线电机轨道交通系统的特点，分别从线路、隧道、桥梁、轨道、车站、车辆段等方面分析其土建工程资源消耗特征，并通过与传统旋转电机驱动轨道交通系统相比较，得出直线电机轨道交通系统在土建工程方面是资源节约型的城市轨道交通系统制式的结论，非常适合大中城市中等运量城市轨道交通发展的要求。
关键词：直线电机；轨道交通；土建工程；资源；节约
Savings in resources and civil work for linear induction
motor rail transit systems
Kong Lingyang Liang Qinghuai
（Urban Rapid Rail Transit Research Center, Beijing Jiaotong University, Beijing 100044, China）
Abstract: Many cities in China are building urban rapid rail transit（URT）systems. However, the environment in built up areas is becoming more constrained and thus leads to increases in project cost and construction risk. A linear induction motor（LIM）driven rail transit system-linear metro system has many advantages, such as, smaller car cross section, light axle load, good kinetic condition, high grade capability, smaller curve radius, low noise, low vibration and simple maintenance. The civil work（line, tunnel, bridge, track, station, car depot, etc.）characteristics and resource consumption of LIM powered systems are analyzed. Based on a comparison with the conventional rotary motor metro system, the LIM powered system is proved to be a‘low cost, efficient benefit’and resource-saving urban rail transit system and suitable as medium capacity urban transit for medium or large cities.
Keywords: linear motor; rail transit; civil work; resources; saving
E-mail: lingyang-k@163.com
平均收益期在工程投资互斥方案评价中的应用
陈喜群 郑思齐
（清华大学，北京100084）
摘要：在工程投资项目的经济评价中，常需要对若干互斥方案进行方案比选，净现值（NPV）最大准则是可靠的方法，而单纯依靠内部收益率（IRR）最大可能会得到错误的结论。但NPV最大仅反映了财富最大化，并未反映资金利用效率。本文借鉴金融学中麦考利存续期（Macaulay duration，即加权平均任期），引入能更好地反映资金利用效率的现金流平均收益期（DR）指标，探讨它与NPV和IRR之间的相互关系，发现当方案的平均收益期和内部收益率趋势相同，必然导致折现值会有相同趋势。本文还揭示了DR值的直观几何含义，这能够简化经济效果的评价方法。同时，本文针对互斥投资方案中的特殊形式修正了平均收益期的概念，使得修正值和原值在项目IRR附近具有明显的相关关系。最后，本文还在非常规投资项目中应用DR指标对项目NPV图进行区域分化，并赋予不同的经济含义。这些定量的研究结果对于应用平均收益期进行互斥方案辅助决策分析有重要的意义。
关键词：互斥方案；平均收益期；修正平均收益期；经济效果评价
Average duration of return for evaluation of mutually exclusive projects
Chen Xiqun Zheng Siqi
（Tsinghua University, Beijing 100084, China）
Abstract: Net Present Value（NPV）and Internal Rate of Return（IRR）are the widely-used tools for evaluating mutually exclusive projects. Maximization of NPV is a reliable criterion, while IRR maximization may lead to a wrong decision. Borrowing the concept of Macaulay Duration from financial economics, an index of cash flow weighted average Duration of Return（DR）is set forth to better reflect the cash flow efficiency of a project. Relationships of DR with NPV and IRR are examined. It is found that for two mutually exclusive projects, if their DRs and IRRs bear the same relationships, NPV will also follow the same relationship direction. The geometric implication of DR is shown, which can simplify the economic evaluation process. A modified average duration of return is introduced to the evaluation of mutually exclusive projects, and it is found that this index is highly correlated with its original value around the IRR point. Based on the DR index, the NPV chart of non-conventional projects can be divided into different parts with specific economic implications.
Keywords: mutually exclusive projects; average duration of return; modified average duration of return; economic evaluation
E-mail: chenxq04@mails.tsinghua.edu.cn
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