高温后方钢管混凝土双向偏压构件试验

为了更好地对高温作用后钢管混凝土的残余力学性能进行评估(特别是双向偏心构件的力学性能),为制订火灾作用后钢管混凝土的残余力学性能鉴定标准积累素材.笔者对恒高温作用后方钢管混凝土双向偏压构件的力学性能进行了15个试件的试验研究,设计了专用的双向偏心受压加载装置,并对影响构件残余力学性能的因素进行了试验分析.研究发现,高温后方钢管混凝土双向偏压构件仍有较高承载力,较好的延性,影响承载力的主要因素是温度.     

Calculating the elastic moduli of steel-fiber reinforced concrete using a dedicated empirical formula

The equivalent inclusion method (EIM) is adopted to study the characteristics of the equivalent material properties of steel-fiber reinforced concrete as a function of the volume fraction and the length to diameter ratio of the fibers. It is found that the equivalent material moduli of concrete reinforce with randomly orientated and distributed fibers are insensitive to the length to diameter ratio of the steel fibers. A set of empirical formulae is then proposed for the purposes of engineering applications. The proposed empirical model can simplify the calculation of the equivalent material moduli. Verifications of the proposed empirical formulae with the EIM model and with experimental data are performed with two examples. The first is a compression test. The second is 4 point bending test. The empirical formulae, based on the equivalent inclusion method proposed in this study, represent an alternative means of quickly calculating the effective elastic modulus of steel-fiber reinforced concrete materials.     

纤维增强塑料筋混凝土梁延性的计算方法

根据纤维增强塑料筋(FRP筋)及其混凝土梁的力学性能,建立了纤维增强塑料筋混凝土梁达到纤维增强塑料筋名义屈服强度的截面曲率和梁最终破坏的截面曲率的表达式.以此为基础,探讨了纤维增强塑料筋混凝土梁截面曲率延性的计算方法.结果表明,纤维增强塑料筋混凝土梁截面曲率延性系数分别随纤维增强塑料筋配筋率的减小和混凝土强度的提高而增大.     

GFRP管增强混凝土结构的轴压强度临界值

为完善和发展FRP管增强混凝土结构的设计与计算理论，在确定组合结构轴心受压时所经历的3个典型工作阶段后，运用经典层合板理论和组分材料相互约束条件，归纳出弹塑性阶段终点时约束管和核心混凝土的轴向应力预测方程．在壳体与核心柱体界面无黏接力的情况下，用合成法得到GFRP管增强混凝土柱轴心受压状态下的强度临界值，从而可以预测任意组合下该种结构的工作强度．分析了各性能参数对GFRP管混凝土结构轴心受压强度设计指标的影响，结果表明，纤维缠绕角与组合结构的强度临界值之间呈非线性变化状态，且在不同的缠绕角范围内，强度临界值呈现出不同的变化趋势．而含量比与强度临界值之间存在近似线性关系，且成正比．     

预防预应力混凝土梁端开裂的措施

桥梁后张法预应力梁端锚下混凝土局部承受很大压应力，在工程中张拉钢绞线时会遇到锚下受压区混凝土开裂的情况。通过计算、经验进行适当地配筋以及改进张拉工艺就可以避免这种情况的发生。     

水泥混凝土路面早期裂缝的原因及防治

对造成水泥混凝土路面早期裂缝的原因进行了分析，并提出防治措施。     

钢骨混凝土大偏心受压柱承载力计算

通过对两组钢骨混凝土柱大偏心受压柱的试验研究并在总结前人研究的基础上,分析钢骨混凝土柱的受力特点和破坏模式,提出钢骨混凝土柱的极限承载力计算公式,并与试验结果进行对比,结果是令人满意的.     

机电轨道衡快速改造实践

针对机电结合轨道衡使用年限长、计量精度差、急需更新改造的现状。为缩短工期，在不停秤的情况下设计制造了工字钢及钢板焊接而成的横梁与原基础联接，使停秤时间由30天减少为2天．测试表明，各项功能正常，器件防护良好，为中准确度级合格．应用表明。称重速度快、性能稳定。减少了计量误差，提高了衡器精度，各项技术指标符合要求。     

Escapable Conclusions: Toomela (2003) and the Universality of Trait Structure.

A. Toomela (2003) concluded that personality structure may be shaped by a cultural mechanism, word meaning structure, and that the apparent universality of the Five-Factor Model (FFM) was the result of inadequate sampling of concrete thinkers. A reanalysis using targeted rotation showed that the intended structure was generally replicated; small deviations in the most concrete thinkers were probably due to measurement error. The reanalysis authors found no evidence of structural differences in a second sample of adults classified as concrete or abstract thinkers. The FFM structure has been replicated in many samples containing individuals with cognitive or educational limitations; observer ratings may be preferred if these limitations are severe. To date, there is no compelling evidence that culture affects personality structure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)