xx年中央电大土木工程力学(本)(历届试题)小抄

xx年中央电大土木工程力学(本)(历届试题)小抄内容摘要：

( )。 专业好文档 第 26 页 共 32 页 A． 2 B． 3 C． 4 D． 5 3．静定结构产生内力的原因有（ ）。 A． 荷载作用 B． 支座位移 C． 温度变化 D． 制造误差 4．超静定结构产生内力的原因有 ( )。 A．荷载作用与温度变化 B．支座位移 C．制造误差 D． 以上四 种原因 5．结构位移计算公式利用什么原理推导的 ( )。 A．位移互等原理 B．虚位移原理 C．虚功原理 D．反力互等原理 6．机动法作静定梁影响线的理论依据是 ( )。 A．虚力原理 B．虚位移原理 C．位移互等定理 D．叠加原理 7．在图示结构中，为使体系自振频率  增大，可以 ( )。 A．增大 PF B．增大 m C．增大 EI D．增大 l 8．图示简支梁中间截面的弯矩为 ( )。 A． 82ql B． 42ql C． 22ql D． 2ql 9．一般 情况下结点的不平衡力矩等于 ( )。 A．固端弯矩 B．传递弯矩 专业好文档 第 27 页 共 32 页 C．分配弯矩 D．附加刚臂中的约束反力矩 10．超静定结构的超静定次数等于结构中 ( )。 A．约束的数目 B．多余约束的数目 C．结点数 D．杆件数 三（ 10分） 作图示静定梁的弯矩图。 四、（ 16分） 用力 法计算图示结构，作弯矩图。 EI=常数。 五 、（ 14分） 用位移法计算图示刚架，列出典型方程，求出系数项及自由项。 EI=常数。 参考答案 一、判断题（以 √ 表示正确，以表示错误。 每小题 3 分，共 30 分） 1． 2． √ 3． 4． √ 5． √ 6． 7． √ 8． 9． 10． 二、 单项 选择题（ 每小题 3 分，共 30 分。 在所列备选项中，选一项正确的或最好的作为答案，将选专业好文档 第 28 页 共 32 页 项号填入各题的括号中 ） 1． A 2． B 3． A 4． D 5． C 6． B 7． C 8． A 9． D 10． B 三（ 10分） 四、（ 16分） 解：（ 1）一次超静定，基本体系和基本未知量，如图 (a)所示。 （ 2）列力法 方程 11111  px  （ 3）作 1M 图，见图 (b) 作 PM 图，见图 (c) （ 4）计算 11 、 P1 EIEIEIdEIM s 325 6444138442112111   EIEIdEIMM sPP 311 60422021111   )(321451 kNx  （ 5）作 M 图 专业好文档 第 29 页 共 32 页 五 、（ 14分） 解： 4EIi 典型方程 01111  PFk ik 1111 mkNF P  51 专业好文档 第 30 页 共 32 页 If we don39。 t do that it will go on and go on. We have to stop it。 we need the courage to do it. His ments came hours after Fifa vicepresident Jeffrey Webb also in London for the FA39。 s celebrations said he wanted to meet Ivory Coast international Toure to discuss his plaint. CSKA general director Roman Babaev says the matter has been exaggerated by the Ivorian and the British media. Blatter, 77, said: It has been decided by the Fifa congress that it is a nonsense for racism to be dealt with with fines. You can always find money from somebody to pay them. It is a nonsense to have matches played without spectators because it is against the spirit of football and against the visiting team. It is all nonsense. We can do something better to fight racism and discrimination. This is one of the villains we have today in our game. But it is only with harsh sanctions that racism and discrimination can be washed out of football. The (lack of) air up there Watch mCayman Islandsbased Webb, the head of Fifa39。 s antiracism taskforce, is in London for the Football Association39。 s 150th anniversary celebrations and will attend City39。 s Premier League match at Chelsea on Sunday. I am going to be at the match tomorrow and I have asked to meet Yaya Toure, he told BBC Sport. For me it39。 s about how he felt and I would like to speak to him first to find out what his experience was. Uefa has opened disciplinary proceedings against CSKA for the racist behaviour of their fans during City39。 s 21 win. Michel Platini, president of European football39。 s governing body, has also ordered an immediate investigation into the referee39。 s actions. CSKA said they were surprised and disappointed by Toure39。 s plaint. In a statement the Russian side added: We found no racist insults from fans of CSKA. Baumgartner the disappointing news: Mission aborted. The supersonic descent could happen as early as Sunda. The weather plays an important role in this mission. Starting at the ground, conditions have to be very calm winds less than 2 mph, with no precipitation or humidity and limited cloud cover. The balloon, with capsule attached, will move through the lower level of the atmosphere (the troposphere) where our daytoday weather lives. It will climb higher than the tip of Mount Everest ( miles/ kilometers), drifting even higher than the cruising altitude of mercial airliners ( miles/ kilometers) and into the stratosphere. As he crosses the boundary layer (called the tropopause),e can expect a lot of turbulence. The balloon will slowly drift to the edge of space at 120,000 feet ( 专业好文档 第 31 页 共 32 页 Then, I would assume, he will slowly step out onto something resembling an Olympic diving platform. Below, the Earth bees the concrete bottom of a swimming pool that he wants to land on, but not too hard. Still, he39。 ll be traveling fast, so despite the distance, it will not be like diving into the deep end of a pool. It will be like he is diving into the shallow end. Skydiver preps for the big jump When he jumps, he is expected to reach the speed of sound 690 mph (1,110 kph) in less than 40 seconds. Like hitting the top of the water, he will begin to slow as he approaches the more dense air closer to Earth. But this will not be enough to stop him pletely. If he goes too fast or spins out of control, he has a stabilization parachute that can be deployed to slow him down. His team hopes it39。 s not needed. Instead, he plans to deploy his 270squarefoot (25squaremeter) main chute at an altitude of around 5,000 feet (1,524 meters). In order to deploy this chute successfully, he will have to slow to 172 mph (277 kph). He will have a reserve parachute that will open automatically if he loses consciousness at mach speeds. Even if everything goes as planned,。