与扁宽地梁组合的墩式基础的设计和分析

通过比较墩式基础和一般独立刚性基础与挖孔扩底桩的力学性质，分析与扁宽地梁组合的墩式基础的工作机理、地基破坏模式和承载力等问题，讨论持力层土质、墩底直径、墩基埋深和土的密实度对地基承载力提高系数的影响，得到了墩式基础比同样条件的挖孔桩承载力大的结论，求得了墩式基础和人工挖孔桩基础的地基承载力提高系数的经验公式。同时，从人工挖孔桩基础和墩式基础的地基承载力提高系数的对比中还发现，按现行规范设计相对埋深较小的挖孔桩时，其单桩承载力偏大，这在实际工程中是偏于不安全的。     

饱和土液化判别公式的讨论

对2010版和2001版建筑抗震设计规范中饱和土液化判别公式进行了分析和讨论,指出了液化初判公式中几个尚未考虑到的问题;重点讨论了两本规范在液化判别公式形式、判别深度以及参数取值等方面的不同点,并得出了一些有益的结论,具有一定指导意义。     

河道淤泥自保温烧结多孔砖生产技术

研究并提出了利用河道淤泥生产烧结自保温多孔砖的产品配方设计、孔结构优化设计、生产工艺及实际生产关键技术,并在砖厂成功烧制出性能符合GB 13544—2000《烧结多孔砖》要求的河道淤泥自保温烧结多孔砖。     

体外预应力加固混凝土框架梁体外筋应力增量分析

体外预应力是后张预应力体系的一个重要分支,已越来越广泛地应用于桥梁工程和建筑结构以及结构加固.应力增量和二次效应是体外预应力结构设计中两个关键因素,同时也是两个难点问题.国内外对体外预应力的研究大都集中在简支梁,而对超静定梁的研究很少,因此有必要对体外预应力超静定梁进行深入的研究.通过试验重点分析了框架粱体外筋应力增量随荷载增长的规律以及应力增量与梁跨中挠度的关系,并通过综合分析国内外研究资料及试验结果,总结出了一些有益的关于体外预应力加固框架梁应力增量的试验结论,并提出了计算超静定结构应力增量的简要计算公式,这对我们今后进行体外预应力超静定结构设计和加同都能够提供一定的帮助,在港口、水坝、桥梁等结构的建设上也都有广泛的应用前景.     

杭州住宅建筑用电量调查及意义分析

目前,国内绝大多数建筑节能的研究都是基于理论公式或软件热工模拟.由于理论研究和实际情况存在很大差别,最好将理论或模拟的研究结果与实际住宅建筑的用电量相结合.本文首先以杭州市3栋不同时期的住宅楼作为调查研究对象,于2007～2008年进行了为期1年的实际月用电量调查;然后,根据杭州市天气特点,分类并计算出实际采暖制冷用电量;最后,通过对调查结果和相关建筑标准及理论或模拟研究结果进行比较,发现仅仅根据理论公式或热工模拟得出的结果夸大了节能措施或技术的节能效果,不能起到指导建筑节能工作发展的作用,应该采用理论结合实际的方法来研究建筑节能的作用和意义.     

Distortional mechanics of restrained steel sections

This paper presents an overview of the mechanics of distortion in members which have restrained thin-walled steel sections. First, the basic features that characterize the distortion of thin-walled sections under compression and/or bending are explained and the generally adopted kinematical assumptions are presented and discussed. On the basis of these assumptions, a simple procedure to build the distortional displacement fields is proposed. Then, two illustrative examples of restrained sections are given and their distortional displacement fields are built. The I-section illustrates the case of a symmetric section having a distortional displacement field with a single d.o.f. The Z-section exemplifies the case of a non symmetric section having a distortional field with two d.o.f. Based on an energy formulation, the equilibrium equation for buckling analysis of simply supported thin-walled members is derived. For two illustrative examples, the distortional displacement field is used to obtain distortional analytical formulae. Finally, some results (buckling loads and moments) were determined and validated by means of comparison with fully numerical obtained from finite strip analysis.     

机械零件的接触应力计算

传递动力的高副机构、如摩擦轮、凸轮齿轮、链轮传动、滚动轴承、滚动螺旋等,都有接触强度问题,自然也涉及到接触应力。在此对接触应力作较为全面的讨论。     

船用高压重负荷空气压缩机油研究

介绍了船用型高压重负荷空气压缩机油（粘度等级为ＩＳＯ ＶＧ１００）的配方研究与试验评定情况。     

不锈钢焊条的混料回归分析与优化设计

针对焊条配方设计时受总量为 1 0 0 %和各因素都有不同的上下限约束这两个特殊条件制约的情况 ,以焊条配方的计算机辅助设计为手段 ,采用混料回归分析法 ,找到了不锈钢焊条的综合性能指标与焊条各组分之间的回归方程。用二次曲面的主轴梯度法优化目标函数 ,得到了电弧稳定、飞溅小、脱渣性好且焊缝金属含硅量符合国家标准规定的不锈钢焊条的配方     

A modified Dunkerley formula for eigenfrequencies of beams carrying concentrated masses

A frequency analysis of an Euler–Bernoulli beam carrying a concentrated mass at an arbitrary location is presented. The dimensionless frequency equation for classical boundary conditions is obtained by satisfying the differential equations of motion and by imposing the corresponding boundary and compatibility conditions associated to the masses. The resulting transcendental equations are numerically solved for the eigenvalue. On the other hand, the eigenvalue can be predicted merely from the individual beam system carrying a single mass, by virtue of the Dunkerley's formula. A parametric study on the effects of the two masses and their locations is presented for the beam with different boundary conditions. It is found that the Dunkerley's expression can generally yield good approximation if compared with the result associated with the original characteristic equation. The computation time saved owing to the modified Dunkerley method is also illustrated in a comparison. The Dunkerley's method is recommended for the beam carrying more than two masses at different positions, owing to its good approximation and the saving in computational time.