检索结果-南通市图书馆

Anisotropic damage coupled modeling of saturated porous rock

在线全文

学校读者我要写书评

暂无评论

Science china(Technological Sciences) 2010年第10期53卷 2681-2690页

作者： LU yingFa1,2, WU XinXing1,2 & SHAO JianFu3 1 key laboratory of geological hazards on three gorges reservoir area, ministry of education, china three gorges university, yichang 443.02, china 2 School of Civil Engineering, Wuhan university, Wuhan 430071, china 3 university of Sciences and Technologies of Lille, Lille 59655, France key laboratory of geological hazards on three gorges reservoir area Ministry of Education China Three Gorges University Yichang China School of Civil Engineering Wuhan University Wuhan China university of Sciences and Technologies of Lille Lille France

It is widely acknowledged that the natural rock mass is anisotropic and its failing type is also non-isotropic. An orthotropic elastic damaged model has been proposed in which the elastic deformation,the damaged deformation and irreversible deformation can be identified respectively. A second rank damage tensor is employed to characterize the induced damage and damage evolution related to the propagation conditions of microcracks. A specific form of the Gibbs free energy function is used to obtain the effective elastic stiffness and the limited scopes of damage parameters are suggested. The model’s parameter determination is proposed by virtue of conventional tri-axial test. Then,the proposed model is developed to simulate the coupled hydraulic mechanical responses and traction behaviors in different loading paths of porous media.

关键词： anisotropy damage modeling saturated rock tensile failure

Research on forecasting model of sandstone deformation rate during sine wave loading segment under the lag effect

在线全文

学校读者我要写书评

暂无评论

Science china(Technological Sciences) 2010年第5期53卷 1442-1449页

作者： LIU Jie1,2,LI JianLin1,2,QU JianJun1,ZHOU JiFang3,ZHANG ChaoFeng3 & LI JianWu1 1key laboratory of geological hazards on three gorges reservoir area,ministry of education,china three gorges university,yichang 443.02,china 2College of Civil and Hydropower Engineering,china three gorges university,yichang 443.02,china 3Er’tan Hydropower Development Company,Ltd.Chengdu 61000,china key laboratory of geological hazards on three gorges reservoir area Ministry of Education China Three Gorges University Yichang China College of Civil and Hydropower Engineering China Three Gorges University Yichang China Er’ tan Hydropower Development Company Ltd. Chengdu China

To reduce data variance caused by individual differences of different samples,a new experimental method is proposed by loading and unloading the axial forces with different frequencies and different waves of a certain load amplitude to the same rock sample without damaging *** time segments are defined and fractionized into segments I and Ⅱ.Criterions for seg-mentation,definitions of relevant parameters and empirical analysis are also offered *** the course of sinusoidal loading,the serious peak value dislocation of the displacement variation rate and the loading rate is defined as peak ***,the definition of the apparent tangent modulus is put forward and the linear relation between it and the vertical force in the frequency of 0.1,0.2,0.5 Hz sinusoidal loading segment is confirmed to be ever-present on the basis of the test *** the calculating formula of the deformation rate in non-lag time is *** is thus suggested that the deformation rate should be codetermined by the loading rate df/dt and instant load f(t),which well explains the peak dislocation of the time-variable curve peak value of dl/dt and deformation rate of df/*** the lag time derivation model is established and by comparing the calculated values with the measured ones,it is demonstrated that the above formula offers a better simulation of the sandstone deformation rate in the sinusoidal loading segment,with the load amplitude being 96 kN and the frequency ranging from 0.1 Hz to 0.5 Hz.

关键词： lag time segments peak shifting phenomenon apparent tangent modulus deformation rate

Discontinuous deformation analysis based on complementary theory

在线全文

学校读者我要写书评

暂无评论

Science china(Technological Sciences) 2009年第10期52卷 2547-2554页

作者： ZHENG Hong1,2 & JIANG Wei2 1 china three gorges university,key laboratory of geological hazards on three gorges reservoir area,ministry of education, yichang 443.02,china 2 State key laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,china china three gorges university Key Laboratory of Geological Hazards on Three Gorges Reservoir Area Ministry of Education Yichang China State key laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan China

The contact between blocks is treated by the open-close iteration in the conventional discontinuous deformation analysis (DDA),which needs to introduce spurious springs between two blocks in contact and to assume the normal stiffness and the tangential stiffness (the penalty factors). Unreasonable values of stiffness would result in numerical problems. To avoid the penalty factors and the open-close iteration,we reformulate the DDA as a mixed complementary problem (MiCP) and then choose the path Newton method (PNM) to solve the problem. Some examples including those originally designed by Shi are reanalyzed,which proves feasibility of the proposed procedure.

关键词： discontinuous deformation analysis (DDA) contact problems open-close iteration complementary theory non-smooth analysis

在线全文

学校读者我要写书评

暂无评论

生态护坡基材土-岩接触面原位剪切试验研究

岩土力学 2015年第S2期36卷 383-388页

作者：丁瑜杨奇夏振尧许文年三峡大学三峡库区生态环境教育部工程研究中心湖北宜昌443002 三峡大学三峡地区地质灾害与生态环境湖北省协同创新中心湖北宜昌443002 三峡大学三峡库区地质灾害教育部重点实验室湖北宜昌443002 中国电建集团贵阳勘测设计研究院有限公司贵州贵阳550081

基材土-岩接触面剪切力学性能是生态护坡体系长久稳定的关键,相关研究可为解决基材脱落难题、完善生态防护技术体系提供必要依据和指导。采用自制的原位剪切仪对4种不同粗糙起伏的基材土-岩接触面进行了原位剪切试验,结果表明,基材土-... 详细信息

基材土-岩接触面剪切力学性能是生态护坡体系长久稳定的关键,相关研究可为解决基材脱落难题、完善生态防护技术体系提供必要依据和指导。采用自制的原位剪切仪对4种不同粗糙起伏的基材土-岩接触面进行了原位剪切试验,结果表明,基材土-岩接触面剪切应力-位移表现出典型的软化特性,具有明显的初始线弹性变形、弹塑性变形、峰后软化以及残余剪切变形4个阶段。分析发现,文中试验条件下凸起高度算数平均偏差Ra在4 mm以下时,峰值剪切强度增加速度较快,随后呈逐渐减弱趋势;残余剪切强度、峰值剪切位移以及进入残余阶段的剪切位移与粗糙凸起高度算数平均偏差呈近线性正相关关系。可见实施生态护坡时合理地控制坡面粗糙起伏,有助于提高土-岩接触面峰值剪切强度和残余剪切强度,改善其变形性能,对防护体系的长期整体稳定具有促进作用。

关键词：生态护坡基材土-岩接触面原位剪切试验剪切软化粗糙度

在线全文

学校读者我要写书评

暂无评论

三峡库首区某滑坡变形特征及影响因素分析

水电能源科学 2011年第8期29卷 106-108页

作者：鲁涛三峡大学三峡库区地质灾害教育部重点实验室湖北宜昌443002

针对库区地质灾害的特点,以三峡库首区秭归县某滑坡为例,基于近年来GPS位移监测、库区降雨与水位变化资料,分析了滑坡的变形特征,并研究了降雨与库水位变化因素对滑坡变形的影响。结果表明,该滑坡变形区呈推动式变形特征,其水平累积位... 详细信息

针对库区地质灾害的特点,以三峡库首区秭归县某滑坡为例,基于近年来GPS位移监测、库区降雨与水位变化资料,分析了滑坡的变形特征,并研究了降雨与库水位变化因素对滑坡变形的影响。结果表明,该滑坡变形区呈推动式变形特征,其水平累积位移曲线具周期性台阶状位移特征,且受降雨和库水位变化影响较大,两者联合作用影响更大。

关键词：三峡库区滑坡变形特征影响因素降雨库区水位

AN APPLICATION OF LABVIEW ON AUTOMATIC DATA ACQUISITION AND CONTROL IN GEOTECHNICAL laboratory TESTS

在线全文

学校读者我要写书评

暂无评论

微计算机信息 2009年第16期25卷 119-121页

作者： ZHANG Hua WU Zheng-guang ZHANG Wei-wei(443002 china three gorges university, key laboratory of geological hazards on three gorges reservoir area, Min-istry of education, yichang, Hubei, china)

The characteristics of USB data acquisition system NI cDAQ and its control software LabVIEW are *** methods for controlling GDS pressure and volume controller by LabVIEW through serial port communication are presented.A practical data sharing method among geotechnical testing systems is *** an application case on a modified conventional soil triaxial testing system, the automatic triaxial testing system is designed by *** on the control panel, the cell pressure and back pressure can be controlled independently and the testing data can be recorded automatically.

关键词：计算机系统智能系统数据管理数据共享

在线全文

学校读者我要写书评

暂无评论

黄龙滩电厂扩建工程进场边坡有限元分析

岩土工程学报 2013年第S2期35卷 202-206页

作者：郭永成李建林王兴霞三峡大学土木与建筑学院湖北宜昌443002 三峡大学三峡库区地质灾害教育部重点实验室湖北宜昌443002 三峡大学水利与环境学院湖北宜昌443002

简要地介绍了黄龙滩电厂扩建工程概况以及该工程进场边坡坍塌情况,指出维护该边坡稳定性要进行治理的必要性。根据工程卸荷特点和相关文献资料,绘制了边坡岩体卸荷量与变形模量的关系图。分析进场边坡的工程特点,采用了卸荷岩体力学理... 详细信息

简要地介绍了黄龙滩电厂扩建工程概况以及该工程进场边坡坍塌情况,指出维护该边坡稳定性要进行治理的必要性。根据工程卸荷特点和相关文献资料,绘制了边坡岩体卸荷量与变形模量的关系图。分析进场边坡的工程特点,采用了卸荷岩体力学理论与方法对该边坡进行有限元分析,分为初始应力场、边坡开挖、边坡开挖卸荷、边坡加固等4种工况进行计算,得出边坡变形的相关规律,运用卸荷岩体力学理论计算所得的最大水平和竖直位移比常规计算的位移值都要大,且其在各个剖面的变化规律基本是一致的。加固措施对边坡开挖面水平位移的约束不明显,但对开挖面附近区域的应力状态有较大的改善,利于边坡的稳定。研究结果可为边坡的加固设计提供参考。

关键词：扩建工程卸荷有限元位移

在线全文

学校读者我要写书评

暂无评论

隧洞灌浆压力施加方法的有限元模拟

水电能源科学 2010年第1期28卷 101-103页

作者：刘先锋三峡大学三峡库区地质灾害教育部重点实验室湖北宜昌443002

针对隧洞开挖和支护模拟时灌浆压力的施加难度,采用ANSYS有限元法对潘口导流洞三种不同的施加灌浆压力方案进行模拟计算,获得了隧洞在开挖支护并承受灌浆压力后的位移场和应力场分布规律。通过对比分析认为方案3较合理,为隧洞灌浆压力... 详细信息

针对隧洞开挖和支护模拟时灌浆压力的施加难度,采用ANSYS有限元法对潘口导流洞三种不同的施加灌浆压力方案进行模拟计算,获得了隧洞在开挖支护并承受灌浆压力后的位移场和应力场分布规律。通过对比分析认为方案3较合理,为隧洞灌浆压力的施加提供了参考。

关键词：隧洞灌浆压力有限元开挖支护

在线全文

学校读者我要写书评

暂无评论

深部软弱岩体置换体对岩质边坡支护效果分析

岩土力学 2015年第S1期36卷 476-480页

作者：宛良朋汤开宇李建林曹毅胡静武汉大学水利水电学院湖北武汉430072 三峡大学三峡库区地质灾害教育部重点实验室湖北宜昌443002

大岗山水电站右岸边坡位于大渡河断裂和磨西断裂所切割的断块上,地震发生频繁且烈度高,岩体卸荷强烈,构造稳定性差,裂隙发育集中。已有研究成果显示出边坡开挖过程中锚索支护的重要性,也有较多学者对抗剪洞支护的设计进行了较全面的研... 详细信息

大岗山水电站右岸边坡位于大渡河断裂和磨西断裂所切割的断块上,地震发生频繁且烈度高,岩体卸荷强烈,构造稳定性差,裂隙发育集中。已有研究成果显示出边坡开挖过程中锚索支护的重要性,也有较多学者对抗剪洞支护的设计进行了较全面的研究。在已有的锚索支护基础上,基于卸荷理论对设计抗剪洞的再次支护效果和和采用拟静力法模拟的抗震效果进行评估,通过不同高程的关键点的位移响应,较系统地论证抗剪洞设置的必要性。通过研究应力的变化发现锚索支护段和抗剪洞支护段之间形成较为明显的拉裂区域。对工程后期监测提出建议。

关键词：开挖支护抗剪支护位移响应拉裂区域