电大土木工程力学(本)作业三答案小抄参考

专业好文档作业三参考答案一、选择题1A 2C 3D 4D 5A二、判断题1 2 3 4 5三、用位移法计算图示连续梁，并绘出弯矩图。各杆EI相同且为常数。（10分）10kN/m4m6mABC解：（1）选取基本结构如下图所示，1为基本未知量。基本结构ABC1（2）写出位移法方程如下：k111+ F1P= 0（3）计算系数k11及自由项F1P 令，则 iAB =3i， iBC =2i作图和MP图如下：2i图ABC112i6i2iMP图（kNm）ABC k11 = 12i+2i =14i kNm（4）求解位移法基本未知量 将系数及自由项代入位移法方程，得： （5）作M图 ABC19(20)1.91.9M图（kNm） 四、用位移法计算图示刚架，并绘制弯矩图。（10分）30kN/mE4mABCD2EI4m4m2EI2EIEIEIF2m15kN解： （1）选取基本结构如下图所示，1、2为基本未知量。EABCDF12基本结构（2）写出位移法方程如下： k111+ k122+ F1P= 0 k211+ k222+ F 2P= 0（3）计算系数及自由项 令，则 iAB = iBC =2i， iBE = iCF = i， iCD=4 i 作图、图和MP图如下：EABCDF1图2i8i4i4i8i4i k11 = 8i+4i+8i =20i k21 =4i k21 = k12 =4iEABCDF1图2i8i4i4i k22 = 8i+4i=12iEABCDFMP图（kNm）403040 F1P =40 kNm F2P =-30 kNm（4）求解位移法基本未知量 将系数及自由项代入位移法方程，得： 20i1+ 4i2+40= 0 4i1 +12i2-30= 0解得： （5）作M图EABCDFM图（kNm）50.73018.67.9(60)16.410.75.413.66.8五、用位移法计算图示刚架，并绘出弯矩图。（10分）EABCD2EILEIEIEIFLLEIqq解： （1）对称结构受对称荷载作用，可简化为如下结构：EADLEILEIq选取基本结构如图所示，1为基本未知量。EAD1基本结构（2）写出位移法方程如下：k111+ F1P= 0（3）计算系数k11及自由项F1P 令，则 iAD = iDE =i作图和MP图如下：EAD图14i4i2i2i k11 = 4i+4i =8iEADF1PMP图 （4）求解位移法基本未知量 将系数及自由项代入位移法方程，得： （5）作M图 EADM图由对称性，得原结构的M图如下：EADM图FBC六、用位移法计算图示刚架(利用对称性)，并绘出弯矩图。各杆EI相同且为常数。（10分）18kN/m6mABCD6m6m6m18kN/mEF解： （1）对称结构受对称荷载作用，可简化为如下结构：18kN/m6mAB3m6mEG选取基本结构如图所示，1为基本未知量。ABEG1（2）写出位移法方程如下：k111+ F1P= 0（3）计算系数k11及自由项F1P 令，则 iAB = iBE =i， iBG =2i作图和MP图如下：GABE图12i2i4i4i2i k11 = 4i+4i +2i =10iABGE54MP图（kNm）54 F1P = 54 kNm（4）求解位移法基本未知量 将系数及自由项代入位移法方程，得： （5）作M图 ABGE64.8M图（kNm）(81)32.421.610.810.8由对称性，得原结构的M图如下：ABE64.8M图（kNm）(81)32.421.610.810.8CDF21.664.8(81)32.410.8七、用力矩分配法计算图示结构，并绘出弯矩图。各杆EI相同且为常数。（10分）48kN/mABCD6m6m3m24kN3m解：计算分配系数， 分配与传递计算0.429分配系数固端弯矩最后弯矩144单位（kNm）-82.8982.86分配与传递0.57100-14461.780.090-100.85100.85-0.6000.4290.5710-2782.2241.11-67.83-90.28-45.1425.7719.3712.89-7.36-5.53-3.681.582.101.05-0.45-0.300.130.17-0.05-0.04-0.03作M图。ABCD82.86100.85(216)M图（kNm）八、用力矩分配法计算图示结构，并绘出弯矩图。各杆EI相同且为常数。（10分）8kN/mABCD6m6m3m32kN3m3mE24kNm解：梁的悬臂 DE 为一静定部分，可求得 MDE =-36kNm，FQDE = 24kN。将结点 D 简化为铰支端，则 MDE 与 FQDE 应作为外力作用于结点 D 右侧，因此可按下图计算：ABCD6m6m3m32kN3m24kNm24kN36kNm计算分配系数 分配与传递计算0.5分配系数固端弯矩最后弯矩单位（kNm）5.07分配与传递0.50360120.04-12.4512.45-0.13360.4290.5710-186.853.43-1.720.490.370.25-0.86-0.010.02-0.07固点反力矩-24012665.15-1.72-0.86-0.13-0.070.03-0.0110.1413.84M图（kNm）(48)5.07ABCDE10.1413.8412.4536（4）作M图九、用力矩分配法计算图示结构，并绘出弯矩图。各杆EI相同且为常数。（10分）10kN/m10kN32kNEABCD2m2m2m2m4m解：此刚架可按下图计算：10kN32kNEBC2m2m4m20kN20kNm20kNm计算分配系数 EBC分配系数固端弯矩最后弯矩单位（kNm）2000.4290.5710-14-2.57固点反力矩0-3.43BE分配与传递20-1.72-16.5720-3.43-1.72 分配与传递计算（4）作M图16.57(32)1.7220EABCD203.43M图（kNm）十、用力矩分配法计算图示结构，并绘出弯矩图。各杆EI相同且为常数。（10分）10kN/m20kNEABCD4m2m2m4m解：计算分配系数 分配与传递计算单位（kNm）100.2730.5-10-2.7320EABCD0.3640.364BABCBD0.5CBCE-3.64-3.64-1.82-4.09-4.09-2.050.560.750.750.38-0.19-0.19-0.100.030.040.040.02-0.01-0.01DB4.29-4.29EC17.86-2.85-15.0-1.820.380.02-1.42-2.05-0.10-2.15作M图EABCD17.86(20)4.29152.15M图（kNm）(20)4.292.851.42Winger Tuivasa-Sheck, who scored two tries in the Kiwis 20-18 semi-final win over England, has been passed fit after a lower-leg injury, while Slater has been named at full-back but is still recovering from a knee injury aggravated against USA.Both sides boast 100% records heading into the encounter but Australia have not conceded a try since Josh Charnleys effort in their first pool match against England on the opening day.Aussie winger Jarryd Hayne is the competitions top try scorer with nine, closely followed by Tuivasa-Sheck with eight.But it is recently named Rugby League International Federation player of the year Sonny Bill Williams who has attracted the most interest in the tournament so far.The Kiwi - with a tournament high 17 offloads - has the chance of becoming the first player to win the World Cup in both rugby league and rugby union after triumphing with the All Blacks in 2011."Id give every award back in a heartbeat just to get across the line this weekend," said Williams.The (lack of) air up there Watch mCayman Islands-based Webb, the head of Fifas anti-racism taskforce, is in London for the Football Associations 150th anniversary celebrations and will attend Citys 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 its about how he felt and I would like to speak to him first to find out what his experience was."Uefa hasopened disciplinary proceedings against CSKAfor the "racist behaviour of their fans" duringCitys 2-1 win.Michel Platini, president of European footballs governing body, has also ordered an immediate investigation into the referees actions.CSKA said they were "surprised and disappointed" by Toures complaint. 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 day-to-day weather lives. It will climb higher than the tip of Mount Everest (5.5 miles/8.85 kilometers), drifting even higher than the cruising altitude of commercial airliners (5.6 miles/9.17 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 ( Then, I would assume, he will slowly step out onto something resembling an Olympic diving platform.They blew it in 2008 when they got caught cold in the final and they will not make the same mistake against the Kiwis in Manchester.Five years ago they cruised through to the final and so far history has repeated itself here - the last try they conceded was scored by Englands Josh Charnley in the opening game of the tournament.That could be classed as a weakness, a team under-cooked - but I have been impressed by the Kangaroos focus in their games since then.They have been concentrating on the sort of stuff that wins you tough, even contests - strong defence, especially on their own goal-line, completing sets and a good kick-chase. Theyve been great at all the unglamorous stuff that often goes unnoticed in the stands but not by your team-mates.It is as though their entire tournament has been preparation for the final.In Johnathan Thurston, Cooper Cronk, Cameron Smith and either Billy Slater or Greg Inglis at full-back they have a spine that is unmatched in rugby league. They have played in so many high-pressure games - a priceless asset going into Saturday.The Kiwis are a lot less experienced but winning a dramatic match like their semi-final against England will do wonders for their confidence.They defeated Australia in the Four Nations final in 2010 and the last World Cup, and know they can rise to the big occasion.17