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Failure Envelopes of Wide-Shallow Composite Bucket Foundation for Offshore Wind Turbines in Silty Sand

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Transactions of Tianjin University 2018年第2期24卷 182-190页

作者： Yonggang Liu yaohua guo Hongyan Ding Puyang Zhang State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University School of Civil Engineering Tianjin University

The wide-shallow composite bucket foundation(WSCBF) is a new type of offshore wind power foundation that can be built on land and rapidly installed offshore, there by effectively reducing the construction time and costs of offshore wind power foundation. In this study, the horizontal bearing capacity is calculated by finite element simulation and compared with test results to verify the validity of results. In this process, the vertical load and bending load are respectively calculated by the finite element simulation. Under the vertical load effect, the bucket foundation and the soil inside are regarded as a whole, and the corresponding buckling failure mode is obtained. The ultimate vertical bearing capacity is calculated using empirical and theoretical formulas; the theoretical formula is also revised by finite element results. Under bending load, the rotational center of the composite bucket foundation(in a region close to the bucket bottom) gradually moves from the left of the central axis(reverse to loading direction) to the nearby compartment boards along the loading direction. The H–M envelope line shows a linear relationship, and it is determined that the vertical and bending ultimate bearing capacities can be improved by an appropriate vertical load.

关键词： Wide-shallow composite bucket foundation Silty sand Off shore wind turbines

Seismic Performance of High-Strength Short Concrete Column with High-Strength Stirrups Constraints

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Transactions of Tianjin University 2017年第4期23卷 360-369页

作者： Hongyan Ding Yuan Liu Chao Han yaohua guo State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Tianjin 300072 China Key Laboratory of Coast Civil Structure Safety of Ministry of Education Tianjin 300072 China School of Civil Engineering Tianjin University Tianjin 300072 China

The seismic performance of four short concrete columns was investigated under low cycle and repeated loads, including the failure characteristics, hysteretic behavior, rigidity degeneracy and steel-bar stress. The influences of reinforcement strength, stirrup ratio and shear span ratio were also compared. Test results reveal that the restriction effect of stirrups can improve the peak stress, so the bearing capacity of specimen can be improved; for the high-strength short concrete column with high-strength stirrups, it was more reasonable to use ultimate displacement angle to reflect the ductility of the specimen, and the yield strength of high-strength stirrups should be devalued when calculating the stirrup characteristic value; the seismic performance of short column would be improved with the increase of volume–stirrup ratio and shear span ratio; the high-strength stirrups and high-strength longitudinal reinforcements did not yield when the load acting on the specimen reached the peak value, which brought adequate safety stock to these short columns. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg.

关键词： Columns (structural) Concrete construction Concretes Hysteresis Reinforced concrete Reinforcement Seismic waves Seismology Shear flow

Influences of Installment Tensioning Technology on Bearing Capacity of Rectangular Prestressed Concrete Beam

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Transactions of Tianjin University 2017年第2期23卷 122-129页

作者： Hongyan Ding Peng Liu Puyang Zhang Yan Zhu yaohua guo State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Tianjin 300072 China Key Laboratory of Coast Civil Structure Safety of Ministry of Education Tianjin 300072 China School of Civil Engineering Tianjin UniversityTianjin 300072 China

To obtain the relationship between use of installment tensioning technology and the bearing capacity of prestressed concrete beams, tensile and cyclic loading tests are conducted on five rectangular prestressed concreted specimens. Two types of prestressed tensioning methods are adopted in the tests, one uses installment tensioning technology to tension beams on days 4, 12, and 8, 12, respectively, and the other adopts the conventional method to tension the beam on day 28 only. The age of concrete, number of times tensioned, and the prestress value of early tensioning are considered in tests. Results show that use of installment tensioning technology has no effect on the bending failure pattern of prestressed concrete beams, but it reduces prestress loss and increases crack and yield loads. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg.

关键词： Bearing capacity Concretes Cyclic loads Prestressed beams and girders Prestressed concrete

Distributed Adaptive Attitude Synchronization of Multiple Spacecraft with External Disturbances

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Distributed Adaptive Attitude Synchronization of Multiple Sp...

Design of Offshore Wind Power Foundation with Multi-bucket

第25届中国控制与决策会议

作者： Dapeng Yang Xiangdong Liu Chao Gan yaohua guo Key laboratory for Intelligent Control ＆ Decision of Complex Systems Beijing Institute of Technology

ISBN: (纸本)9781467355322

This paper considers the distributed attitude synchronization problem for multiple spacecraft with external disturbances. Distributed discontinuous adaptive controller is designed based on the relative attitudes and angular velocities of neighboring spacecraft and attitude synchronization can be reached for any communication graph containing a directed spanning tree. To tackle the chattering effect caused by the discontinuous controller, a continuous controller is further proposed, under which both the synchronization errors and the adaptive gains are ultimately bounded. Extensions to the case with a leader-follower communication graph with the leader as the spanning tree’s root are further studied.

关键词： Multiple Spacecraft Attitude Synchronization Distributed Control Cooperative Control

来源： cnki会议评论

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Transactions of Tianjin University 2016年第6期22卷 502-507页

作者：张浦阳石建超丁红岩郭耀华 State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Tianjin 300072 China Key Laboratory of Coast Civil Structure Safety Ministry of Education Tianjin University Tianjin 300072 China School of Civil Engineering Tianjin University Tianjin 300072 China

Three- and four-bucket offshore wind power foundations with a new form of force-transferring structure are proposed in this paper, and the integrated finite element model of foundation-soil-transition structure is established by using ABAQUS. The carrying capacity of the proposed foundations is studied under vertical load, horizontal load and bending moment. It can be seen that the vertical bearing capacity of multi-bucket foundation can be roughly estimated by the vertical bearing capacity of single-bucket; the horizontal bearing capacity of the three-bucket foundation scheme is controlled by displacement, while that of the four-bucket foundation scheme is controlled by the internal forces of soils. Moreover, the carrying capacity is provided by the overall structure formed by multi-bucket before soil failure. Compared with the conventional single-bucket foundation, there are mainly tension and pressure that are applied to the multi-bucket foundation, so that the carrying capacity of the foundation can be fully utilized. The probability of soil failure can be well reduced with the proposed multi-bucket foundation, and the stress transmission of force-transferring structure is more consistent through steel beams with variable cross-section.

关键词： offshore wind power multi-bucket foundation rotation point force-transferring structure

Experimental Research on Seismic Performance of Storey-Adding Frame Structures

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Transactions of Tianjin University 2016年第1期22卷 43-49页

作者：丁红岩郭耀华梁玉国张浦阳 State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Tianjin 300072 China School of Civil Engineering Tianjin University Tianjin 300072 China Key Laboratory of Coast Civil Structure Safety of Ministry of Education Tianjin University Tianjin 300072 China Hebei Academy of Building Research Shijiazhuang 050021 China

The seismic behaviors of an integral concreting frame, a light steel storey-adding frame and a storeyadding frame strengthened with carbon fiber reinforced polymer(CFRP)were investigated under low-cycle and repeated load(scale 1∶3). The failure characteristics, hysteretic behavior, rigidity degeneracy, deflection ductility and energy-dissipation capacity of the three specimens were compared. The test results reveal that chemicallybonded rebar technique can meet the requirements of storey-adding engineering. The carrying capacity, the deflection ductility, the energy-dissipating capacity and seismic performance of the light steel storey-adding frame are higher than those of the integral concreting frame, and they are the highest in the storey-adding frame strengthened with CFRP.

关键词： storey-adding frame post-installing rebar technique pseudo-static test seismic performance

机载光电系统目标威胁估计的模糊贝叶斯网络方法

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传感技术学报 2011年第11期24卷 1584-1589页

作者：史志富郭曜华第二炮兵工程大学603教研室西安710025 中国人民解放军边防学院营房处西安710108

针对机载光电传感器系统所能够提供的目标特征信息,提出利用模糊贝叶斯网络理论建立目标威胁估计模型来辅助决策者进行威胁判断。模型首先研究了机载光电传感器所能提供的目标特征及其对威胁程度的影响;然后选取合适的特征值并利用模糊... 详细信息

针对机载光电传感器系统所能够提供的目标特征信息,提出利用模糊贝叶斯网络理论建立目标威胁估计模型来辅助决策者进行威胁判断。模型首先研究了机载光电传感器所能提供的目标特征及其对威胁程度的影响;然后选取合适的特征值并利用模糊理论方法对其进行模糊划分,从而建立了目标威胁估计的模糊贝叶斯网络模型,最后通过贝叶斯网络推理算法获得目标的威胁程度判断,为决策者进行决策提供技术依据。通过对整个威胁估计过程的仿真模拟验证了该模型的有效性和模拟结果的可靠性。

关键词：机载光电系统威胁估计贝叶斯网络模糊理论

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工程施工计划优化决策支持系统

西南交通大学学报 1999年第1期34卷 120-125页

作者：林杰郭耀煌西南交通大学

针对工程施工进度的合理安排和资源的最优利用，从项目施工管理的角度出发，通过计算机人机交互系统，综合运用运筹学、经济学、工程科学、决策管理等理论，提出了工程施工计划优化决策支持系统，阐述了其功能、结构及主要模型，并开发... 详细信息

针对工程施工进度的合理安排和资源的最优利用，从项目施工管理的角度出发，通过计算机人机交互系统，综合运用运筹学、经济学、工程科学、决策管理等理论，提出了工程施工计划优化决策支持系统，阐述了其功能、结构及主要模型，并开发了相应软件。该系统为工程施工计划编制者和现场管理人员提供了一种辅助管理与决策环境，是施工企业进行决策的有效技术手段。

关键词：决策支持系统工程项目 PODSS 施工计划

基于非支配排序遗传算法的感载比例阀静特性多目标优化设计

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汽车技术 2010年第10期 1-4页

作者：郭孔辉郭耀华吉林大学汽车动态模拟国家重点实验室

以某匹配感载比例阀的车辆为例,以理想利用附着系数曲线为目标,以ECE制动法规为约束条件,利用非支配排序遗传算法对车辆在空载、半载和满载状态下的制动性能进行了多目标优化,得到了满足设计要求和性能最优的感载比例阀静特性曲线。

关键词：感载比例阀制动性能多目标优化非支配排序遗传算法