( 密 封 线 内 不 答 题 ) ………………………………………密………………………………………………封………………………………………线…………………………………… 学院 专业 座位号 诚信应考,考试作弊将带来严重后果！ 华南理工大学期中考试 《Mechanics of Materials》 注意事项：1. 考前请将密封线内填写清楚； 2. 所有答案请直接答在试卷上(或答题纸上)； 3．考试形式：闭卷； 4. 本试卷共六大题，满分100分， 考试时间120分钟。 Problem score Grading person I II III IV V VI Total score I. Simple calculation problems（ total score 44） _____________ ________ 01. A material is tested in tension. The stress-strain curve for material and the stresses and strains at point A,B. (a) Determine the modulus of elasticity E. (b) Find the elastic and residual strains when point B is reached.(score 5) 姓名 学号 02. Determine the moment of inertia with respect to centroid axis zc.(Note: The diameter of the half circle is d and C is the centroid.) (score 5) 1 03. A and B shown in the figure have the same diameter d. Determine the maximum shear stress. (score 5) 04.A cantilever beam having rectangular cross sectional dimensions 200mm×60mm is made of the wood. A load F=2kN acts on the free end. The wood fiber at point A is at angle 45º to the horizontal. Determine the normal and shear stresses acting on inclined section pass through the fiber at point A. (score 5) 二、Draw loading and bending-moment M diagrams for the beam based upon the shear-force diagram (see figure).(No concentrated couples applied on the beam)（score 15） 2 三、The rigid frame ABCD supports a couple forces F. Assume that the flexural rigidity EI is constant throughout the frame. Determine the deflection δ between A and B using the energy method.（score 15） 四、A solid circular shaft AB of steel(G=80GPa) having diameter d=60mm and length l=2m is fixed at left end A. The wheel is rigidly attached to the end B of diameter D=400mm(see figure). The weight W=1kN hangs on the wheel by the steel cable. The cable has length l1=10m, section area A=100mm2 and the modulus of elasticity E=200GPa. Determine the maximum shear stress in the shaft and dropping distance of the weight.（score 15） 3 五. A cantilever beam AB with length a=1m shown in the figure supports a uniform load of intensity q=10kN/m and concentrated load F=2qa(acting in xy plane, φ=30º). The section modulus S and cross-sectional area A are 237×10-6m3 and 35.5×10-4m2, respectively. Determine the maximum tensile and compressive stresses on the critical section of the beam. （score 15） 六.The cantilever beam AC has circular cross section with diameter d=20mm. AB is pinned-pinned column. An object of weight G=600N is dropped onto the end of beam A from a height H=5mm. Check the stability with respect to column AB using a factor of safety nst=2.5.(Note: Beam and column have same modulus of elasticity E=200GPa, λp=101, l1=2m, l2=1m, Iz=1×10-6m4). 4 本文来源：https://www.wddqw.com/doc/3c525e46bb4ae45c3b3567ec102de2bd9605de3e.html