2007春材料力學(xué)期末考試試題B卷英文版

1、(NOTE: This final exam, 100 marks in total, is worth 50 percent of your final score.) 1. Single Choice Questions: (8 questions, 3 marks each, 24 marks in total)1-1. Two beams have the same length , flexural rigidity and bending moment. Denote the deflection as and the radius of curvature as . Then m

2、easured in a common coordinate system, for the two beams, ( )A. are the same，but are not necessarily the same.B. are not necessarily the same，but are the same.C. both and are not necessarily the same. D. both and are the same. 1-2. Shown in Fig. 1-2 is a punching machine. For the steel plate, denote

3、 its ultimate shear strength as , and its yield strength as . In order to punch a rounded hole with a diameter in the steel plate having a thickness of , the punching force applied on the punch should be no less than ( ).A. B. C. D. Fig. 1-2 Fig. 1-31-3. For a simply supported beam, if the loading s

4、tyle changes from Fig. 1-3(a) to Fig. 1-3(b), then the maximum bending moment and the maximum shear force in the beam vary as follows: ( )A. decreases, remains the same. B. both of them decrease. C. remains the same, decreases. D. both of them remain the same.1-4. The degree of statical indeterminac

5、y of the structure shown in Fig. 1-4 is ( ). A. 0 B. 1 C. 2 D. 3 Fig. 1-4 Fig. 1-51-5. Among the four simply supported beams shown in Fig. 1-5, ( ) has the minimum maximum deflection.1-6. Rupture usually occurs when hot water is filled into a thick glass cup. When this is so, cracks first appear at

6、the ( ) of the glass.A. inner wall B. intermediate wall C. outer wall D. both (A) and (C) (simultaneously) 1-7. The allowable shear stress based on the third and fourth strength theories can be expressed in terms of the allowable tensile stress respectively as ( ).A. and B. and C. and D. and 1-8. On

7、 the analysis of skew bending for a bar with an arbitrary solid cross-section, the resolving directions for the load should be a pair of ( ).A. arbitrary perpendicular coordinate axes B. perpendicular coordinate axes passing through the centroid C. horizontal and vertial perpendicular coordinate axe

8、s passing through the centroidD. principal centroidal axes2. As shown in Fig. 2, beam AB has a length of and a flexural rigidity of . A movable clockwise concentrated moment is applied on the beam at a distance away from pin A. If here is taken to be , determine the deflection curve for beam AB in t

9、erms of , which is measured from pin A. （16 marks） Fig. 23. The L-shaped bar shown in Fig. 3 is made of two circular bars AB and BC, both having a diameter . The length of bar AB and BC is and , respectively. The L-shaped bar has a fixed support at A. At C, there are two loads applied. One is along

10、the direction, the other is along the direction. Their magnitudes can be read from the figure. If the allowable stress is , perform a full strength checking of the L-shaped bar using the fourth strength theory. Note that the effect of transverse shear stress can be neglected. (16 marks)Fig. 34. Show

11、n in Fig. 4 is a truss with an axial rigidity of for all its rod members. A horizontal force is applied at B. Determine the horizontal displacement at C. （14 marks） Fig. 45. Beam AB, as shown in Fig. 5, has a flexural rigidity of for all its segments. The beam is fixedly supported at A and roller-su

12、pported at B. A clockwise concentrated moment is applied at C. Draw the bending moment diagram of the beam (note: neglect the effect of axial force). (14 marks)Fig. 56. As shown in Fig. 6, beam AB is pin-supported at both A and B. BD is a connecting rod and is made of the same material as the beam AB. Both AB and BD have circular cross-section and their diameters are and , respectively. A weight fall