基于差异沉降控制的桩基优化设计     

潘海龙 《石家庄铁路职业技术学院学报》2021,(1):62-66,83

为解决传统桩基承载力低的问题,基于差异沉降控制优化设计桩基.分析桩基设计存在的问题,主要包括:桩基支承刚度设定误差高、桩基差异沉降大、桩基结构设计不合理,通过设定桩基支承刚度,控制桩基差异沉降,采用桩基塌孔承桩断裂结构,实现对桩基的优化设计.设计实例分析,结果表明,设计的桩基承载力明显高于对照组,能够解决传统桩基承载力...  相似文献   

The role of shoe design on the prediction of free torque at the shoe–surface interface using pressure insole technology     

Brian Thomas Weaver  Kathleen Fitzsimons  Jerrod Braman 《Sports biomechanics / International Society of Biomechanics in Sports》2016,15(3):370-384

The goal of the current study was to expand on previous work to validate the use of pressure insole technology in conjunction with linear regression models to predict the free torque at the shoe–surface interface that is generated while wearing different athletic shoes. Three distinctly different shoe designs were utilised. The stiffness of each shoe was determined with a material’s testing machine. Six participants wore each shoe that was fitted with an insole pressure measurement device and performed rotation trials on an embedded force plate. A pressure sensor mask was constructed from those sensors having a high linear correlation with free torque values. Linear regression models were developed to predict free torques from these pressure sensor data. The models were able to accurately predict their own free torque well (RMS error 3.72 ± 0.74 Nm), but not that of the other shoes (RMS error 10.43 ± 3.79 Nm). Models performing self-prediction were also able to measure differences in shoe stiffness. The results of the current study showed the need for participant–shoe specific linear regression models to insure high prediction accuracy of free torques from pressure sensor data during isolated internal and external rotations of the body with respect to a planted foot.  相似文献   

滑动运动副接触刚度控制研究     

张丽  孙宝元 《大连大学学报》2002,23(2):48-50

设计并制造了基于NiTi形状记忆合金驱动的间隙可调整（或接触刚度可控）运动副．实验结果表明：这种运动幅间隙可控性好，其接触动刚度变化范围大（最大动刚度是原始动刚度的11倍），具有理想的自适应抗振特性．  相似文献   

获取＂动力硬化＂的一般程式     

张大钧  张海根  刘又午 《天津大学学报(英文版)》1995,(1)

阐述一种获取＂动力硬化＂的一般程式。基于凯恩方程导出做大范围运动任意柔体的运动方程。用几何非线性应变一位移关系和角速度的非线性表达式正确实现线性化，一般情况下可自然获取＂动力硬化＂项。休斯敦方法中偏速度和偏角速度阵列的概念和推导拓宽到柔体，并做为分析的基础。通过用于梁和板模型数值计算的结果证实了所述程式是普遍有效的。  相似文献   

基于Plaxis 2D的基坑支护中内支撑对支护桩的影响分析     

许芸芸  孙忠强 《唐山学院学报》2010,(3):22-24

借助Plaxis 2D的有限元分析程序,计算不同支撑刚度下的支护桩变形及内力,揭示了支护桩支撑轴力与支撑刚度之间的变化规律,分析了两者比值对支护桩的影响曲线,并得出近似比值,用以指导工程实际。  相似文献   

直齿锥齿轮刚度在ANSYS中的有限元分析     

王龙宝 《安徽职业技术学院学报》2012,(4):1-3

运用ANSYS软件对直齿锥齿轮刚度进行有限元分析,确定了直齿锥齿轮刚度的影响因素及规律性,同时将其有限元计算值与其理论计算值进行比较。结果表明:直齿锥齿轮刚度理论计算值与理论计算值偏差随着锥角的增大而增大。  相似文献   

The performance of the ice hockey slap and wrist shots: the effects of stick construction and player skill   总被引：1，自引：0，他引：1  

T.?-C.?Wu  D.?PearsallEmail author  A.?Hodges  R.?Turcotte  R.?Lefebvre  D.?Montgomery  H.?Bateni 《Sports Engineering》2003,6(1):31-39

The purpose of this study was to examine the interaction of players’ skill level, body strength, and sticks of various construction and stiffness on the performance of the slap and wrist shots in ice hockey. Twenty male and twenty female subjects were tested. Ten of each gender group were considered skilled and ten unskilled. In addition to general strength tests, each subject performed the slap and wrist shots with three stick shafts of different construction and stiffness. Shot mechanics were evaluated by simultaneously recording ground reaction forces from a force plate, stick movement and bending from high speed filming and peak puck velocity from a radar gun. Data were analysed with a 4-way repeated measures ANOVA for several dependent variables including peak puck velocity, peak Z (vertical) force, peak bending and stick to ground angles, peak angular deflection of the shaft, and hand placement on the stick. The results indicated that: 1) the slap shot was much faster than the wrist shot corresponding to greater vertical loading force, stick bending, and greater width of the hand placement; 2) the puck velocity was influenced by skill level and body strength but not stick type; and, 3) that skilled players were able to generate more vertical force and bend of the stick, in part, by adjusting their hand positions on the stick. Further studies are needed to address the specific influence of body strength and skill on the techniques of these shots and in relation to stick material and construction properties.  相似文献   

低氧运动大鼠血清血管内皮生长因子与动脉血氧分压的相关研究   总被引：7，自引：3，他引：4  

郑澜  陆爱云  周志宏 《体育科学》2004,24(7):28-30

选用健康雄性SD大鼠80只，采用递增负荷跑台运动及递增程度的低氧处理。应用酶联免疫检测、血气分析检测及相关分析方法。研究不同低氧方式运动对动脉血氧分压和血清血管内皮生长因子的影响，探讨动脉血氧分压与血清血管内皮生长因子相关关系。结果表明：动脉血氧分压随着低氧的介入及低氧程度的增加而下降，与此同时，血清血管内皮生长因子含量下降；血清血管内皮生长因子含量下降与动脉血氧分压下降显著相关。  相似文献   

FSAE赛车车架刚度特性分析     

彭倩  韩锋钢  洪汉池  郭福森 《鹭江职业大学学报》2014,(3):7-11

车架刚度及发动机悬置安装点动刚度是影响FSAE赛车振动性能的重要因素,通过建立某FSAE赛车车架有限元模型,进行车架扭转刚度及悬置安装点动刚度分析,研究车架静态与动态刚度性能。结果表明：增大车架驾驶舱段截面可有效提高扭转刚度;悬置安装点各向动刚度值以纵向最大,横向最小。结合模态振型及加速度响应曲线能够较好地反映发动机舱的振动特性。  相似文献   

汽车前置后驱动力总成悬置系统设计优化     

覃丽霜  覃臻  杨玉玲 《大众科技》2014,(12)

随着时代发展,在汽车领域噪声和振动问题也日益重要。文章从发动机悬置的总体布置、结构类型、刚度匹配到后期的实际测试,介绍一款前置后驱动力总成悬置系统优化设计方案。  相似文献