土方路基回弹弯沉检测标准确定方法研究

结合工程实例，详细论述了土方路基回弹弯沉检测标准的确定方法．指出，用回归分析建立回归方程确定弯沉检测标准时，应就同样的实测数据，同时建立具有足够保证率的以回弹模量E0为自变量、回弹弯沉l0为因变量和以l0为自变量、E0为因变量的两个回归方程；至于选用哪种形式的回归方程，应根据两方程对应曲线交点坐标与设计回弹模量大小关系而定．如果设计回弹模量E0小于交点纵坐标Ep，则采用以l0为自变量、E0为因变量的回归方程；反之，则采用另一个．     

土方路基回弹弯沉检测标准确定方法研究

结合工程实例,详细论述了土方路基回弹弯沉检测标准的确定方法.指出,用回归分析建立回归方程确定弯沉检测标准时,应就同样的实测数据,同时建立具有足够保证率的以回弹模量E0为自变量、回弹弯沉l0为因变量和以l0为自变量、E0为因变量的两个回归方程;至于选用哪种形式的回归方程,应根据两方程对应曲线交点坐标与设计回弹模量大小关系而定.如果设计回弹模量E0小于交点纵坐标Ep,则采用以l0为自变量、E0为因变量的回归方程;反之,则采用另一个.     

冲击拉伸载荷下材料大变形的测量方法

由于橡胶基复合材料在冲击拉伸载菏下瞬时变形大,利用应变片等传统测量方法很难准确测得其应力-应变关系,针对橡胶基复合材料,利用应变自主 等传统测量方法准确测得应力-应变关系,提出在冲击拉伸载菏下橡胶复合材料大变形测量方法,这种方法的原理是利用激光-光栅将材料的大变形转换成相应的光脉冲数,通过确定脉冲数可测量变形菜值,实验表明：这种方法原理可行,测量范围宽、精度高、速度快、实现简单,且易于信号自动纪录和数据处理。     

Gauge-meter model building based on the effect of elastic deformation of rolls in a plate mill

The calculation error of the gauge-meter model will affect the gap setting precision and the self-learn precision of rolling force. The precision of the gauge-meter model is strongly influenced by plate width, working roll radius, backup roll radius, working roll crown, backup roll crown, and rolling force. The influence rules are hard to get by measuring. Taking a conventional 4-h plate mill as the research subject, these influences were transferred into the calculation of roll deflection and flattening deformation. To calculate these deformations, the theory of the influence function method was adopted. By modifying the traditional gauge-meter model, a novel model of the effect of roll elastic deformation on the gap setting was built by data fitting. By this model, it was convenient to analyze the variation caused by the rolling condition. Combining the elastic deformation model of rolls with the kiss-rolls method, a gauge-meter model was put forward for plate thickness prediction. The prediction precision of thickness was greatly improved by the new gauge-meter model.     

适用于大变形分析的平面协调梁单元

常用的平面欧拉梁单元位移插值模式应用于大变形问题的T.L.有限元分析时，不能满足单元间转动位移协调要求，降低了有限元的求解效率和计算精度.针对该问题，导出了Lagrangian描述下平面梁单元节点转角和位移导数间的关系，根据单元间平动位移和转动位移的协调条件构造出大变形梁单元的位移插值模式.在此基础上给出了单元Green应变的表达式，并基于虚功原理得出了平面欧拉梁大变形条件下的有限单元列式.编制了采用修正牛顿法求解的有限元程序，通过数值算例验证了单元的合理性和有效性.计算结果表明，该单元具有计算量小、计算精度高的优点.     

火车岭隧道软弱围岩大变形特征及机理分析

在现场调研、工程地质勘察及隧道监控量测的基础上，研究了十漫高速公路火车岭隧道施工中出现的大变形问题，通过分析该隧道变形破坏特征，从围岩岩性条件、地下水条件及地应力条件等因素对该隧道大变形机制进行了研究，结果表明，大变形为围岩塑性流动及围岩膨胀变形的综合作用。提出了综合治理措施，以确保隧道安全顺利贯通。     

弹性地基上复合材料夹层梁的解析分析

针对弹性地基上的复合材料夹层梁 ,从具有两个广义位移的梁理论出发 ,导出了问题的数学模型 .采用状态空间法 ,并定义了一类广义克雷洛夫函数 ,给出了问题的解析解 .为此类问题的具体分析 ,提供了一种简明规范的方法     

弹性车轮纵向力刷子模型分析

为研究弹性车轮结构特点与驱动性能关系,根据刷子模型,将弹性车轮的弹性梁看做连接在刚性轮毂上的一系列可以产生伸缩变形的弹性刷毛组成,这些刷毛能起到承受垂向载荷以及产生车轮纵向和侧向力的作用,然后对弹性车轮纵向力进行深入研究。在刚性路面,建立垂向和纵向力分布函数,根据地面接触情况积分求解纵向合力,并研究了弹性车轮弹性梁厚度与纵向合力的关系及弹性梁滑移率与纵向合力的关系。这为弹性车轮的优化设计提供一定的帮助。     

大系统的一种模型降阶方法

为简化大系统分散控制器的设计 ,提出了一种基于内部平衡系统的模型简化方法 .这种方法首先把一个一致稳定的系统转化成一个内部平衡系统 ,然后选择一个内部优势子系统作为降阶模型 ,该子系统可保留系统的强可控可观部分 ,并有一定的稳定性 .最后给出了计算实例 ,并对所得结果进行了分析     

A cellular automata evacuation model considering friction and repulsion

At present, the study of traffic flow has got constructive achievements[1-5]. The pe- destrian flow, similar to the traffic flow, is attracting more and more attention. Pedestrian evacuation is a multi-agent system composed of pedestrians with interactions. Its dy- namic characters are similar to those of the traffic flow. The local interactions among pedestrians and those between pedestrian and environment (e.g. wall, door, smoke) de- cide the complicated, global behaviors of pedestrians, e.g…     

Effects of liquefaction-induced large lateral ground deformation on pile foundations

The pile-soil system interaction computational model in liquefaction-induced lateral spreading ground was established by the finite difference numerical method.Considering an elastic-plastic subgrade reaction method,numerical methods involving finite difference approach of pile in liquefaction-induced lateral spreading ground were derived and implemented into a finite difference program.Based on the monotonic loading tests on saturated sand after liquefaction,the liquefaction lateral deformation of the site where group piles are located was predicted.The effects of lateral ground deformation after liquefaction on a group of pile foundations were studied using the fmite difference program mentioned above,and the failure mechanism of group piles in liquefaction-induced lateral spreading ground was obtained.The applicability of the program was preliminarily verified.The results show that the bending moments at the interfaces between liquefied and non-liquefied soil layers are larger than those at the pile＇s top when the pile＇s top is embedded.The value of the additional static bending moment is larger than the peak dynamic bending moment during the earthquake,so in the pile foundation design,more than the superstructure＇s dynamics should be considered and the effect of lateral ground deformation on pile foundations cannot be neglected.     

Elastoplastic model for discontinuous shear deformation of deep rock mass

Deep rock mass possesses some unusual properties due to high earth stress,which further result in new problems that have not been well understood and explained up to date.In order to investigate the deformation mechanism,the complete deformation process of deep rock mass,with a great emphasis on local shear deformation stage,was analyzed in detail.The quasi continuous shear deformation of the deep rock mass is described by a combination of smooth functions:the averaged distribution of the original deformati...     

高速滑坡临滑变形能突变模型的研究

在应用传统理论的基础上 ,吸取非线性科学理论——突变理论的思想及方法 ,建立高速滑坡尖点突变模型 ,导出变形能公式 ,从而为滑坡滑速定量描述及其涌浪预报提供新的思想及方法     

基于弹性网络模型的细胞色素c折叠核的识别研究

来自细菌的细胞色素c与来自马的细胞色素c具有很高的序列和结构相似性,但是二者的折叠/去折叠路径及折叠核的位置具有很大的差异,导致这种差异的原因目前并不清楚。本文采用迭代的高斯网络方法研究了上述两个蛋白的去折叠过程,并成功识别出两个体系的折叠核位置,与实验很好地吻合。结果表明,两个体系拓扑结构的差异是导致二者折叠特征和折叠核位置不同的主要原因。     

多辊冷轧机弹性曲线的幂函数模型研究

采用空压靠法,实测了多辊冷轧机的压下位移以及上下工作辊间压靠力,绘制了轧机的实测弹性曲线。通过对实测弹性曲线规律的分析,经对各种不同非线性模型结构采用单纯形法回归计算,发现幂函数模型结构最符合该实测弹性曲线变化规律,经与常规线性模型结构回归计算结果进行比较,证明该幂函数模型精度较高。采用该幂函数模型可大大提高轧机实际弹性曲线的拟合精度。     

基于时变参数模型的边坡变形分析应用研究

为揭示边坡变形规律,保证边坡安全,采用灰色系统理论对变形监测数据进行分析,在经典灰色GM（1,1）模型的基础上,建立了时变参数模型,提高了模型的拟合精度和预测能力.通过计算机编程进行解算,提高了模型的实用程度.实例计算表明,时变参数预测模型具有更好的预测效果.     

Game model of safety monitoring for arch dam deformation

Arch dam deformation is comprehensively affected by water pressure,temperature,dam's structural behavior and material properties as well as other factors.Among them the water pressure and temperature are external factors(source factors) that cause dam deformation,and dam's structural behavior and material properties are the internal factors of deformation(resistance factors).The dam deformation is the result of the mutual game playing between source factors and resistance factors.Therefore,resistance factor...     

条形基础稳定性弹塑性大变形有限元分析

对土体失稳过程中弹塑性大变形的问题,采用大变形问题的Updated Lagrangian描述方法,建立了土体稳定分析的弹塑性大变形有限元模型,提出了坐标更新和非线性方程组线性化的方法：计算了均布竖向荷载情况下的条形基础地基稳定性,通过与Prandtl解和弹塑性小变形有限元法所得结果的对比,说明了用弹塑性大变形有限元法进行土体稳定性计算是可行的．通过对倾斜荷载作用并考虑土体自重情况下的条形基础地基稳定性分析,表明弹塑性大变形有限元法不仅能反映土体抗剪强度指标对土体稳定性影响,而且也能反映土体弹性参数对土体稳定性影响,说明了用弹塑性大变形有限元法计算土体稳定性的合理性及对工程安全的重要性．     

金桥煤矿井筒变形实时测量与井筒破坏突变模型

针对金桥煤矿副井涌沙引发井筒变形的实际问题 ,研究了采用GPS技术实时监测井筒动态非线性变形方法 ;运用了突变理论 ,建立了井筒破坏的突变模型 ;给出了井筒变形的控制变量与状态变量表达式 ;对有效地治理损害的井筒具有重大指导作用 .     

基于微体积扰动的颗粒增强复合材料有效弹性性能的预测模型

基于对埋入无限大基体中的夹杂作微”膨胀”型体积扰动的假设,提出复合材料有效弹性模量的一种预测模型。以自洽理论为出发点,推导出基体和夹杂均为各向同性的颗粒增强复合材料有效弹性模量的细观力学解析计算公式。以颗粒增强金属基复合材料和纳米增强相复合材料为算例对有效弹性模量进行了预测,并与已有的实验及用传统的Mori—Tnanka法的预测结果进行比较,证明所提出的解析公式的合理性和工程实用性。