THERMAL CONTACT STRESSES OF BI-METAL STRIP THERMOSTAT

The distribution of shearing and normal stresses on the con-tact surface of the two strips composing a thermostat is foundin closed form.They are of local type and concentrated nearthe ends of the strip along a length almost equal to the thick-ness of the strip.     

材料力学的内容更新

迦里略在1638年出版“两种新的科学”一书。书中的新科学之一为动力学,而另一新科学为建筑材料的力学性能及梁的理论。这就是材料力学的创始。迦里略创造两种新的科学,牛顿与莱勃尼次发明微积分,哥白尼以太阳为中心的宇宙观被证实。这几件事标志着在十七世纪人类见到了现代科学的兴起。     

ON THE RESTRICTED TORSION OF NARROW RECTANGULAR CROSS SECTION BY KIRCHHOFF’S THIN PLATE THEORY

Kirchhoff’s thin plate theory is used to solve the restrictedtorsion of narrow rectangular cross section as this problem isequivalent to the bending of a rectangular cantilever plate by atwisting moment at the free end.The results obtained not onlyprove the angle of twist obtained by Prof.Timoshenko using theenergy method but give us stresses.     

Bending of Uniformly Cantilever Rectangular Plates

An exact solution is given for the bending of uniformly loaded rectangular cantilever plates byusing the idea of generalized simply supported edge together with the method of superposition.Asillustrative examples,a square plate and a rectangular plate with the ratio of the clamped edge to theneighbouring free edge equal to two are solved numerically.The results are compared with thoseobtained from approximate methods to confirm the validity of the method presented.     

Analysis of adhesive lap joint

This paper is to solve the interlaminar stresses of adhesive lap joint by the energy method without considering the adhesive layer. The joint is made of two identical narrow plates. Two cases are discussed: one is for the isotropic material and the other is for orthotropic material. Because of the different materials forming the joint, the length of distribution and the magnitude of the interlaminar, stresses for the two cases will be very different.Projects supported by the Science Fund of Chines Academy of Sciences (1986–1988).     

胶合搭接接头*

本文以能量法求解无胶层厚度的搭接接头的层间应力.接头是由两相同的狭长板条组成.讨论了两种情形:一是各向同性材料的,一是正交各向异性材料的.由于构成接头的材料不同,层间应力的分布长度与数值均有很大差异.     

叠层复合材料杆弯曲的层间应力(Ⅱ)

一矩形横截面的叠层复合材料杆,由以一种材料为中心部分,及另一种材料的上下两相同的盖板所组成.以线性弯曲应力所组成的力偶,作用于杆两端的中心部分(图1a),使杆弯曲.本文将探讨层间应力,以表明力是怎样通过胶合面传递给盖板的.     

叠层复合材料杆弯曲的层间应力(Ⅰ)

一矩形横截面的叠层复合材料杆,由以一种材料为中心部分,及另一种材料的上下两相同的盖板所组成.各等于P的压力和张力,均匀分布在上下盖板的两端.它们形成两力偶使杆弯曲.本文将探讨层间应力,以表明力是怎样通过胶合面而传递的.     

Load supporting prefabricated wall reinforced by a frame

This load supporting prefabricated wall consists of a thin plate reinforced along its boundaries by a frame. With the loads acting on the frame, the plate has its boundary conditions defined neither by forces nor by displacements. On the basis of satisfying the biharmonic equation of the stress function for the plate, we make the total strain energy to be minimum to ensure the compatibility of displacements for the two elastic bodies. Thus we get a set of infinite simultaneous equations. The results obtained indicate the method of solution is effective.     

弹性地基上的自由矩形板

在弹性地基上的自由矩形板的弯曲,在弹性薄板理论中也是个难题.本文以叠加法提供一个精确解.它满足微分方程,自由边界的条件以及自由角点条件.这样将导致一系列无穷联立方程.所解的问题为在板的中点作用一集中力这问题.我们并以地基反力应与这集中力相平衡.校核所作的计算是否正确.