荷载对称性与连续梁三弯矩方程

应用广义图乘法分析荷载与连续梁三弯矩方程关系.若杆内有对称荷载,则三弯矩方程简单;简支梁弯矩图的面积能表示荷载对连续三个支座弯矩的作用.任意荷载的作用含反对称荷载分量的图乘剪力的作用.若杆内荷载是同方向,则反对称荷载比弯矩图面积的影响小.     

小波变换模极大值点在信号去噪中的应用

如何去除信号中的噪声．得到纯净的信号是信号处理过程中一个热点技术。本研究根据噪声与信号的小波变换模极大值点在多尺度空间上具有不同的特性,对信号进行了噪声消除。试验结果表明,使用傅里叶变换和coif2小波模极大值点法对信号去噪,都能够有效地去除信号中的噪声,且重构后的信号非常逼近原始信号．但coif2小波模极大值点法去噪效果更好。     

AN IMPROVED AXISYMMETRIC WILSON NONCONFORMING FINITE ELEMENT METHOD FOR STRESS ANALYSIS

ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｎｏｎｃｏｎｆｏｒｍｉｎｇｆｉｎｉｔｅｅｌｅｍｅｎｔＱ6(Ｗｉｌｓｏｎｅｔａｌ.,1 973)ｉｍｐｒｏｖｅｓｔｈｅａｃｃｕｒａｃｙｏｆｃｏｎｆｏｒｍ ｉｎｇｆｉｎｉｔｅｅｌｅｍｅｎｔＱ4ｂｙｉｎｃｏｒｐｏｒａｔｉｎｇｈｉｇｈｅｒｏｒ ｄｅｒｎｏｎｃｏｎｆｏｒｍｉｎｇｄｉｓｐｌａｃｅｍｅｎｔｓｗｈｉｃｈｒｅｄｕｃｅｔｈｅｓｈｅａｒｌｏｃｋｉｎｇ,ｓｏｆｔｅｎｔｈｅｓｔｉｆｆｎｅｓｓｏｆｃｏｍｐａｔｉ ｂｌｅｅｌｅｍｅｎｔｓａｎｄｉｎｃｒｅａｓｅｔｈｅｉｎｔｅｒｐｏｌａｔｉｏｎａｃ…     

异形阳台边梁设计的计算机方法

该文从工程设计、施工中常见的质量问题分析入手,着重讨论了异形阳台边梁的受力性能,并提出了解决问题的办法,即采用作者设计的钢筋砼受弯、剪、扭构件配筋实用计算程序。     

三折线线性软化土体中球孔扩张问题解答

以三折线线性软化模型为基础,结合Tresca屈服准则和不相关联的流动法则,同时考虑了塑性区弹性变形,推导了具有应变软化和剪胀特性的土体球孔扩张问题的解。运用所得解分析了不同剪胀特性和不同软化程度对球形孔扩张结果的影响。     

Replacing stirrups of self-compacting concrete beams with steel fibers

Based on the investigation of fiber influence on workability of self-compacting concrete (SCC), tests were carried out on two series of SCC rectangular simply supported beams, which were made of hooked steel fibers reinforced concrete with or without stirrups, subjected to four-point symmetrically placed vertical loads. The major test variables are steel fiber contents and stirrup ratios. The results indicate that the ultimate load significantly increases with the increase of fiber content; the addition of ...     

Effect of chloride content on bond behavior between FRP and concrete

For reinforced concrete structures located along the seaside, the penetration of chloride ions into concrete may be a threat to the durability of the structures. Experimental investigations were carried out to study the effect of chloride content on the bond behavior between concrete and fiber reinforced polymer (FRP) plates. Direct shear tests were conducted on the FRP strengthened concrete members. Before testing, the specimens were immersed in NaCl solutions with concentrations ranging from 3%—15% for different time (0—120 d). Then, the specimens were dried and tested to obtain the initial and ultimate debonding loads, together with strain distributions along the FRP plates of different load values. The correlations between chloride content and debonding parameters are established. Test results show that the debonding parameters are closely related to the immersing time rather than the chloride content of the solution.     

植根土壤剪力强度增量评估模式之研究

许多相关研究显示,含有植生根系补强的土壤会增加土壤的凝聚性和剪力强度．当穿过滑动面的根系贯入深度越深,则对于增加土壤剪力强度的功能越大．基于根力模式之研究,植根对土壤剪力强度增量之计算,已呈现明朗而具体化．本研究除应用文献【1】中学者Waldron的根系力学理论外,亦采用文献【2】中陈等人及文献[3】中游等人所提出之根系力学修正模式来估算土壤抗剪强度增量,分析结果显示,考虑植根密度变化与合理之剪力带发展机制模拟,确能得到较准确之评估结果．     

塑料发泡中复杂流场流体动能气泡成核理论

气泡成核、长大与固化定型是泡沫塑料成型的三个基本过程,而气泡成核是最关键的一步。本文分析指出了经典成核理论对于动态聚合物熔体中气泡成核分析的局限性,对静态熔体和复杂流场熔体的气泡成核过程分别进行了能量描述,在此基础上建立了塑料发泡中复杂流场流体动能气泡成核理论,以期对塑料发泡中气泡成核过程进行更加全面的描述并更好地指导发泡过程。最后指出了气泡成核研究的发展方向。     

关于一个求和算子的逼近阶

设f（x）∈c2π,Un（f,x）是f（x）的基于结点x（kn）=（2kπ/2n＋1）（k=0,1,2…n）的求和算子。研究用Un（f,x）逼近f（x）的问题,得到了阶的估计。