CFG桩复合地基承载特性分析     

侯新宇 《江苏广播电视大学学报》2003,14(6):41-43

CFG桩复合地基具有变形模量高、承载力提高幅度大等特点，设计时可以通过改变桩体材料配比，改变桩体直径、桩长、桩距、垫层厚度等设计参数，使承载力提高以达到设计要求。其中，褥垫层有协调桩和桩间土变形的能力，使得桩和桩间土始终参与工作，一般工程中取10～30cm较为合理。  相似文献   

弹性有限长度杆在轴向应力波传播和反射过程中的屈曲     

徐新生  刘书田  郭杏林 《商丘师范学院学报》1996,(Z4)

讨论弹性有限长度杆端部受冲击载荷作用，在轴向应为波传播和反射过程中的动态屈曲问题．利用扰动方程的解、端部支承条件和应力波反射前后波阵面相容条件得到了动态屈曲的分叉条件，临界载荷和屈曲模态．数值结果表明：临界载荷有多个分支且随时间增加而降低；由于应力波在端部的反射，使临界载荷进一步下降．这个结果就解释了实验中的一些现象．  相似文献   

Fuzzy Comprehensive Assessment Method to Determine Tectonic Stress Patterns     

张海  戚蓝  郝彩哲  郭磊 《天津大学学报(英文版)》2007,13(6):462-468

The tectonic stress patterns were determined by a fuzzy comprehensive assessment method. Data of in-situ survey and fault information were utilized in the method. First, by making pressure and tension in the directions of along-river, cross-river, shear clockwise, and shear counterclockwise , 26 types of tectonic stress patterns were presented. And the stress vector of each pattern was obtained with FE software by taking unit displacement as boundary load. Then, by taking the 26 types of tectonic stress patterns as index set and 3 main stresses as factor set and choosing various operators, comparison of directions of computational stress vector and survey stress vector was made and the most possible tectonic stress pattern was obtained. Taking the 26 types of tectonic stress patterns as index set and strike angle as factor set, comparison of relationships between formation of fault and tectonic stress was made,and the tectonic stress patterns were assessed with known fault information. By summarizing the above assessment results, the most impossible tectonic stress pattern was obtained . Finally an engineering case was quoted to validate that the method is more feasible and reliable than traditional empirical method.  相似文献   

幼儿教师工作压力与生活满意度的关联性研究          下载免费PDF全文

许颖 《宁波大学学报(教育科学版)》2020,(6):117-122

摘要:采用问卷调查法对511名幼儿教师进行调查,考察幼儿教师工作压力与生活满意度之间的关联,探讨心理资本和工作倦怠在其中的序列中介效应。结果表明:（1）幼儿教师工作压力、心理资本、工作倦怠、生活满意度两两显著相关;（2）幼儿教师工作压力对生活满意度的直接预测作用不显著,但分别通过心理资本、工作倦怠的独立中介作用以及二者的序列中介作用间接预测生活满意度。研究结果提示不仅要重视缓解幼儿教师的工作压力,降低工作倦怠,还要从提升幼儿教师心理资本、发挥个体资源的保护性作用等途径缓解工作压力对幼儿教师生活满意度的不利影响。  相似文献   

仿生种植牙应力分布的有限元分析     

王宗篪  庄国铭  赖森财  谢培庆  黄庆杰  黄跃 《三明学院学报》2002,19(4):1-3

以上颌中切牙为解剖学基础 ,提出了仿生种植牙模型。相同载荷分别作用于天然牙、仿生牙及骨性结合种植牙模型 ,用二维有限元法计算得到牙周膜和仿生牙周膜的应力分布 ,对三种模型骨界面上的应力分布进行了比较研究  相似文献   

EDTA配位滴定法测定热处理盐浴中的氯化钡     

梁保安 《许昌学院学报》2001,20(2):74-76

研究了用EDTA配位滴定法,结合反滴定方式测定NaCl-BaCl2混合盐中的BaCl2时的相关问题.对照试验的结果表明,该方法测定BaCl2的结果准确、可靠.  相似文献   

甲基橙褪色光度法测定加碘盐中微量碘     

余建平  林燕 《赣南师范学院学报》2005,26(6):49-50

基于硫酸介质中,在溴化钾催化作用下,碘酸根氧化甲基橙褪色作用,据此建立了测定碘的动力学光度法.结果表明,最大吸收波长为507 nm时,碘酸钾浓度在0~1.6 mg/L内呈线性关系,表观摩尔吸收系数为9.17×104L.mol-1cm-1.方法用于加碘盐中碘(V)的测定,结果令人满意.  相似文献   

试论民国时期山东的盐税改革     

宋志东 《许昌学院学报》2007,26(4):89-92

民国时期山东进行了盐税改革。改革牵动着相关各方的利益,遇到了重重阻力,因而改革采取了渐进的方式。期间历经盐税征收机关的调整、民初盐税的统一改革和其后的继续调整三个阶段。山东的盐税改革实现了税目由繁到简、税率由乱到治的转变,税收稳定增长,但税率仍未最终统一。尽管此期山东的盐税改革仍不彻底,还是取得了显著成就。  相似文献   

河北省咸水资源的利用与开发   总被引：2，自引：0，他引：2  

连进元  赵彦红  王观枝 《石家庄职业技术学院学报》2004,16(2):18-21

河北平原是严重缺水地区，由于长期超采地下水，致使河北平原产生一系列的环境地质问题，河北平原同时也藏有大量地下咸水，合理开发利用地下成水资源，是解决河北平原水资源短缺的关键问题，从河北平原咸水分布、储量及咸水在工农业生产方面的作用分析了合理开发与利用地下咸水的优势与意义。  相似文献   

Teacher self-efficacy moderates the relations between imposed pressure from imposed curriculum changes and teacher stress     

David W. Putwain  Nathaniel P. von der Embse 《教育心理学》2019,39(1):51-64

Based on the Job Demands-resources (RD-R) model, the aim of the current study was to examine how pressure arising from imposed curriculum changes and teacher self-efficacy relate to perceived stress in teachers. Participants (839 teachers working in English schools) completed an online survey that contained questions about demographics, self-reported pressure from imposed curriculum changes, teacher self-efficacy, and perceived stress. Pressure from imposed curriculum changes was positively, and teacher self-efficacy negatively, related to perceived stress. Teacher-self efficacy moderated relations between pressure from imposed curriculum changes and perceived stress. High teacher self-efficacy was associated with lower perceived stress, relative to low teacher self-efficacy, when pressure from imposed curriculum changes was low. The differential advantage offered by high self-efficacy declined as pressure from imposed curriculum changes increased.  相似文献