电大建筑力学形成性考核册作业答案

电大【建筑力学】形成性考核册答案一、选择题1.B 2.C 3.C 4.C 5.B6.D 7.B 8.D 9.A 10.D二、填空题1、垂直线2、中心线 背离研究对象3、研究对象 全部作用力4、平行 原力对新作用点5、无关 力偶矩大小6、力偶7、压力8、自由度9、虚铰 瞬铰10、三角形三、计算题1.2. 3、见教材34页例题4.解：体系内几何不变，且无多余约束。5、解：6、7、1）解：一、选择题1.D 2.C 3.C 4.D 5.A 6.C 7.C 8.B 9.D 10.C二、填空题1、轴向拉伸或压缩 剪切 扭转 弯曲2、扭矩 Mn 用右手的四指表示扭矩Mn的转向，拇指的指向离开截面则扭矩为正3、杆件轴线4、剪力5、零杆6、直线 斜直线7、斜直线 二次抛物线8、剪力 集中力9、弯矩 集中力偶10、力偶矩三、计算题：1、解：取截面左边部分为研究对象：Fxi=0 FN1-2F=0得：FN1=2F(拉力)同理可得：FN2=0同理可得：FN3=F(拉力)绘制轴力图。A B C D2F0F+2,3小题同上2、解（1）求支座反力：Fxi=0 FAX-40=0得：FAX40kN （ ）MA(F)=0 FBY420424020得：FBY60kN（）Fyi0 得：FAY20kN（）（2）作弯矩图AC杆 MAC=0AC杆中截面弯矩 MEA80kNm(内侧受拉)MCA80kNm（内侧受拉）CD杆 MCD80kNm（内侧受拉）MDC0DB杆 MDBMBD03）作剪力图用截面法求各杆端剪力AC杆：FQAC=40kN FQEC=FQCA=0CD杆：FQCD=20kN FQDC=60kN(4)作轴力图同理，用截面法求各杆件轴力，作出杆件轴力图第2小题，直接绘制内力图3、解（1）求支座反力：Fxi0 得：FAX=0MA(F)=0 FBY485420得：FBY=12kN()Fyi0 得：FAY=8kN()(2)画受力图，用假象截面在需求内力处将梁分成两部分，取其中一部分为研究对象，画受力图。(3)求内力，画受力图FQ图(kN)4、解：1）求支座反力Fyi0 得FCY3F()MB(F)=0 得：FAX=3F()Fxi0 得：FBX=3F()2）.取结点B为脱离体， FxB0 杆AB为零杆得杆BD的轴力 FNBD3F（拉力）取结点A为脱离体，杆AD为零杆， FxA0得杆AF轴力 FNAF3F（压力）取结点D结点为脱离体得FD杆为零杆，即FD杆的轴力为0DE杆的轴力为3F（拉力）取结点F结点为脱离体FyF0 得FE杆件的轴力为 （压力）FxF0 得FG杆件的轴力为 2F （压力）一、选择题：1.C 2.A 3.B 4.D 5.D6.C 7.C 8.D 9.C 10.D二、填空题1、常数 横向变形系数2、等于3、几乎不增加 增加4、弯矩 最远5、强度 刚度 稳定性条件6、几何变形 应力与应变的物理关系 静力条件7、减小 降低8、长度系数9、大10、计算长度三、计算题2)求杆件应力：2、解：1）圆环对形心轴x,y的惯性矩：2）矩形对圆环对形心轴x的惯性矩：矩形对圆环对形心轴y的惯性矩：一、选择题1.B 2.D 3.D 4.C 5.A6.C 7.B 8.C 9.B 10.C二、填空题1、杆轴为直线2、位移3、轴力 4、荷载 力（力偶）5、反 反6、位移7、未知的结点角位移和未知的结点线位移8、单跨超静定梁的组合体9、位移法10、转动their own conditions to develop the correct road, the maximum to avoid investment risk, gain profit.(three) vigorously promote the brand. To establish brand awareness, awareness of the use of brand, brand value, brand acquisition performance, enhance the competitive strength. Concentrated manpower, careful planning, packaging and publicity of a number of unique, market influence and coverage of the brand, the implementation of key breakthroughs, to enhance the competitive strength, walking business road the competition of alienation and characteristics, the pursuit of stability and development of the market.(four) to promote the integration of resources. To further broaden their horizons, effective integration of resources within the group, the city resources, other industries and regional resources, mutual trust, mutual benefit, seeking win-win principle, in the framework of national policies and regulations, strict inspection and argumentation, legal consultation, examination and approval procedures, strict regulation of economic activities, attract injection the social investment to the industry group, to achieve leveraging the development, ensure that the value of state-owned assets.(five) to strengthen the construction management personnel. Strengthen the management of education and training of cadres and workers of the existing business, firmly establish the concept of the market, enhance the sense of crisis to adapt to market competition, the sense of urgency, improve the ability to respond to market competition, improve management and operation of the market. At the same time, according to the need of industrial development, vigorously the introduction of high-quality management management personnel, and strive to build a high-quality professional management team, hard work, and promote the entire workforce knowledge structure, age structure, structure optimization and upgrading ability, enhance core competitiveness, adapt to the need of market competition.(six) seriously study the policy for policy. Serious research about social support the development of cultural undertakings in the country and the XX policy, especially the policy of industrial development, financial investment policy, financial policy and tax policy, and actively seek policy, projects and funds, enterprise and industry group mission to promote leapfrog development.