2017年電大土木工程力學形成性考核冊作業(yè)一小抄參考

1、土木工程力學（本）形成性考核冊作業(yè)一一、選擇題（每小題 2分，共20分）1 .三剛片組成幾何不變體系的規(guī)則是（B ）A三鏈桿相聯(lián)，不平行也不相交于一點B三鉸兩兩相聯(lián)，三鉸不在一直線上C三鉸三鏈桿相聯(lián)，桿不通過鉸D 一鉸一鏈桿相聯(lián)，桿不過鉸2. 在無多余約束的幾何不變體系上增加二元體后構(gòu)成（C ）A可變體系B瞬變體系C無多余約束的幾何不變體系D有多余約束的幾何不變體系3. 瞬變體系在一般荷載作用下，（C ）A產(chǎn)生很小的內(nèi)力B不產(chǎn)生內(nèi)力C產(chǎn)生很大的內(nèi)力D 不存在靜力解答4. 已知某體系的計算自由度 W=-3,則體系的（ D ）A自由度為3B自由度等于0C多余約束數(shù)等于3 D 多余約束數(shù)大于等于 3

2、5不能作為建筑結(jié)構(gòu)使用的是（D ）A無多余約束的幾何不變體系B有多余約束的幾何不變體系C幾何不變體系D幾何可變體系6圖示桁架有幾根零桿（D ）A 0 B 2 C 4 D 67下圖所示結(jié)構(gòu)的彎矩圖形狀應為A )&圖示多跨靜定梁的基本部分是（B ）A AB部分 B BC 部分 C CD 部分 D DE 部分| ABCDE9 .荷載作用下產(chǎn)生桁架位 移的主要原因是（A ）A 軸向變形B 彎曲變形C 剪切變形D 扭轉(zhuǎn)變形10.三鉸拱在集中力作用下其合理拱軸線形狀是（D ）A折線B 圓弧 C 雙曲線D 拋物線二、判斷題（每小題 2分，共20分）1. 多余約束是體系中不需要的約束。（）2 .如果體

3、系的計算自由度大于零，那么體系一定是幾何可變體系。（）3兩根鏈桿的約束作用相當于一個單鉸。（）4. 一個體系是有n個自由度的幾何可變體系，那么加入n個約束后就成為無多余約束的幾何不變體系。（）5. 兩剛片用三鏈桿相聯(lián)，且三鏈桿平行不等長，則構(gòu)成瞬變體系。（）6. 圖示兩個單跨梁，同跨度同荷載。但橫截面形狀不同，故其內(nèi)力也不相同。（V ）I1O7. 三鉸拱的矢高f越大，水平推力也越大。（）&求桁架內(nèi)力時截面法所截取的隔離體包含兩個或兩個以上的結(jié)點。（）9.某荷載作用下桁架可能存在零桿，它不受內(nèi)力，因此在實際結(jié)構(gòu)中可以將其去掉。10 .試判斷下列彎矩圖是否正確。（）1.、試對圖示平面體系進

4、行幾何組成分析。（每小題5分，共20分）題2-圖題2-圖3.2.4.m1.解：由二元體分析法題2-1（圖原結(jié)構(gòu)是一個無多余約束的幾何不變體系。2. 解：由二元體分析法原結(jié)構(gòu)是一個無多余約束的幾何不變體系。3解：顯然，體系是具有兩個多余約束的幾何不變體系。四、繪制下圖所示各結(jié)構(gòu)的彎矩圖。（每小題10分，共30 分）解：作彎矩圖如下:卜 L/2 M -C3.M40kN 40kN20kN/4m -空D E一 2m 寸 2m _ 土 2m _ 2mM 圖（kNm)Aaaa 一 十 a.解：求支座反力由 M A = 0FBg4a Fpg2a Fpg3a 0Fb5FP4（）Fa|FP3FPFP 04（）用

5、I -I截面將桁架截開，保留右邊部分，受力如圖:由Fp取結(jié)點3Fn3Fp （拉）2C為研究對象，作受力圖如下:FN4 FN4顯然：Fn2Fp （壓）FN2after a lower-leg injury, while Slater has bee n n amed at full-back but is still recoveri ng from a knee injury aggravated aga inst USA.Both sides boast 100% records head ing into the encoun ter but Australia have notcon c

6、eded a try si nce Josh Charnley's effort in their first pool match aga instEn gla nd on the ope ning day.Aussie win ger Jarryd Hayne is the competiti on's top try scorer with nine, closely followed by Tuivasa-Sheck with eight.But it is recently named Rugby League International Federation pla

7、yer of the yearSonny Bill Williams who has attracted the most interest in the tournament so far.The Kiwi - with a tourn ame nt high 17 offloads - has the cha nce of beco ming the firstplayer to win the World Cup in both rugby league and rugby union after triumphing with the All Blacks in 2011."

8、I'd give every award back in a heartbeat just to get across the line this weekend,"said Williams. The (lack of) air up thereWatch mCayma n Isla nds-based Webb, the head of Fifa's an ti-racism taskforce, is inLondon for the Football Association's 150th anniversary celebrations and wi

9、llatte nd City's Premier League match at Chelsea on Sun day."I am going to be at the match tomorrow and I have asked to meet Yaya Toure," hetold BBC Sport."For me it's about how he felt and I would like to speak to him first to find out whathis experie nce was."Uefa has o

10、pened disciplinary proceedings against CSKA for the "racist behaviour of their fans" duringCity's 2-1 win.Michel Plat ini, preside nt of Europea n football's gover ning body, has also ordered an immediate in vestigati on into the referee's acti ons.CSKA said they were "sur

11、prised and disappo in ted" by Toure's complai nt. In a stateme nt the Russia n side added: "We found no racist in sults from fans ofCSKA."Baumgartner the disappointing news: Mission aborted.The supers onic desce nt could happe n as early as Sun da.The weather plays an importa nt r

12、ole in this missi on. Start ing at the gro und, con diti ons have to be very calm - winds less tha n 2 mph, with no precipitati on or humidity and limited cloud cover. The ballo on, with capsule attached, will move through the lower level of the atmosphere (the troposphere) where our day-to-day weat

13、her 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 boun dary layer (called the tropopause),e can expect a lot of tu

14、rbule nce.The balloon will slowly drift to the edge of space at 120,000 feet (Then, I would assume, he will slowly step out onto somethi ng resembli ng an Olympic div ing 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

15、 Manchester.Five years ago they cruised through to the final and so far history has repeated itself here - the last try they con ceded was scored by En gla nd's Josh Char nley in the ope ning game of the tourn ame nt.That could be classed as a weak ness, a team un der-cooked - but I have bee n i

16、mpressed by the Kan garoos' focus in their games since the n. They have bee n concen trati ng on the sort of stuff that wins you tough, eve n con tests - strong defe nee, especially on their own goal-li ne, completi ng sets and a good kick-chase. They've been great at all the unglamorous stu

17、ff that often goes unnoticed in the stands but not by your team-mates.It is as though their en tire tourn ame nt has bee n preparati on for the fin al.In Joh natha n Thurst on, Cooper Cronk, Camer on Smith and either Billy Slater or Greg In glis at full-back they have a spine that is unm atched in rugby league. They have played in so many high-pressure games - a priceless asset going into Saturday.The Kiwis are