電大【土木工程力學(xué)】形考一參考小抄

專業(yè)好文檔一、選擇填空CBA CBA BACD BCAFED AB BC1. 結(jié)點(diǎn)通常簡化為以下三種類型： ( C ) ( B) ( A ) A鉸結(jié)點(diǎn) B剛結(jié)點(diǎn) C組合結(jié)點(diǎn)2. 從幾何角度，結(jié)構(gòu)通?？梢苑譃槿悾?C 通常由若干根桿件相互聯(lián)結(jié)組成，桿件的幾何特征是其長度遠(yuǎn)大于橫截面上兩個方向的尺度。 B 厚度遠(yuǎn)小于其長度和寬度。 A 長、寬、高三個方向尺度大小相近（屬于同一數(shù)量級）。A 實(shí)體結(jié)構(gòu) B板殼結(jié)構(gòu)（薄壁結(jié)構(gòu)）C桿件結(jié)構(gòu) D拱結(jié)構(gòu)3. B 不允許結(jié)構(gòu)在支承處發(fā)生任何方向的移動和轉(zhuǎn)動。A 不允許結(jié)構(gòu)在支承處發(fā)生轉(zhuǎn)動，也不能沿垂直于支承的方向移動，但可以沿平行于支承的方向滑動。 C 只允許結(jié)構(gòu)在支承處繞鉸A轉(zhuǎn)動，而不能發(fā)生任何移動。 D 只約束了支承鏈桿方向的位移，允許結(jié)構(gòu)繞鉸轉(zhuǎn)動，也可以沿著垂直于鏈桿的方向移動。A定向支座 B固定支座 C固定鉸支座 D活動鉸支座4. 根據(jù)荷載的不同特征，荷載可以進(jìn)行如下分類：根據(jù)作用時間可以分為： B永久作用在結(jié)構(gòu)上的不變荷載。 C暫時作用在結(jié)構(gòu)上的可變荷載。 根據(jù)作用的性質(zhì)可以分為： A荷載的大小、方向和位置不隨時間變化或變化比較緩慢，不會使結(jié)構(gòu)產(chǎn)生明顯的振動，計算過程中可忽略慣性力的影響。 F隨時間迅速變化的荷載，會使結(jié)構(gòu)產(chǎn)生明顯的振動，因而計算過程中慣性力的影響不能忽略。根據(jù)作用的方式可以分為： E是指滿布在結(jié)構(gòu)或構(gòu)件某部分面積上的荷載。 D作用在結(jié)構(gòu)上的荷載一般總是分布在一定的面積上，當(dāng)荷載作用面積遠(yuǎn)小于結(jié)構(gòu)或構(gòu)件的尺寸時，可以認(rèn)為此荷載是作用在結(jié)構(gòu)或構(gòu)件的一個點(diǎn)上。A靜力荷載 B恒載 C活載 D集中荷載 E分布荷載 F動力荷載5. 在任意荷載作用下，若不考慮材料的變形，其幾何形狀與位置均保持不變，這樣的體系稱為 A 。即使不考慮材料的變形，在很小的荷載作用下，也會引起其幾何形狀的改變，這樣的體系稱為 B 。 A幾何不變體系 B 幾何可變體系6. 一根鏈桿相當(dāng)于1個約束；一個單鉸相當(dāng)于 B 個約束；一個剛結(jié)點(diǎn)相當(dāng)于 C 個約束。A1 B 2 C 3二、單項(xiàng)多選1. 對圖示平面體系進(jìn)行幾何組成分析，該體系是（ D ）。A. 可變體系 B. 有一個多余約束的幾何不變體系C. 無多余約束的幾何不變體系 D. 有兩個多余約束的幾何不變體系2. 對圖示平面體系進(jìn)行幾何組成分析，該體系是（ B ）。A. 瞬變體系 B. 無多余約束的幾何不變體系C. 有兩個多余約束的幾何不變體系 D. 有一個多余約束的幾何不變體系3. 對圖示平面體系進(jìn)行幾何組成分析，該體系是（ A? ）。A. 瞬變體系B. 可變體系C. 無多余約束的幾何不變體系D. 有一個多余約束的幾何不變體系4. 對圖示平面體系進(jìn)行幾何組成分析，該體系是（ B ）。A. 可變體系 B. 無多余約束的幾何不變體系C. 有兩個多余約束的幾何不變體系 D. 有一個多余約束的幾何不變體系5. 對圖示平面體系進(jìn)行幾何組成分析，該體系是（ B ）。A. 瞬變體系B. 可變體系C. 無多余約束的幾何不變體系D. 有一個多余約束的幾何不變體系6. 對圖示平面體系進(jìn)行幾何組成分析，該體系是（ C ）。A. 瞬變體系B. 可變體系C. 無多余約束的幾何不變體系D. 有一個多余約束的幾何不變體系7. 對圖示平面體系進(jìn)行幾何組成分析，該體系是（ C ）。A. 瞬變體系B. 可變體系C. 無多余約束的幾何不變體系D. 有一個多余約束的幾何不變體系8. 對圖示平面體系進(jìn)行幾何組成分析，該體系是（ B）。A. 瞬變體系B. 無多余約束的幾何不變體系C. 有兩個多余約束的幾何不變體系D. 有一個多余約束的幾何不變體系9. 對圖示平面體系進(jìn)行幾何組成分析，該體系是（ C ）。A. 瞬變體系B. 可變體系C. 無多余約束的幾何不變體系D. 有一個多余約束的幾何不變體系10. 對圖示平面體系進(jìn)行幾何組成分析，該體系是（ A ）。A. 瞬變體系B. 可變體系C. 無多余約束的幾何不變體系D. 有一個多余約束的幾何不變體系11. 一個平面體系的計算自由度W>0，則該體系是（ B ）。 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12. 對圖示平面體系進(jìn)行幾何組成分析，該體系是（ B ）。A. 瞬變體系 B. 可變體系 C. 無多余約束的幾何不變體系 D. 有一個多余約束的幾何不變體系13. 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14. 對圖示平面體系進(jìn)行幾何組成分析，該體系是（ D ）。A. 幾何可變體系 B. 瞬變體系C. 有一個多余約束的幾何不變體系 D. 無多余約束的幾何不變體系15. 對圖示平面體系進(jìn)行幾何組成分析，該體系是（ A ）。A. 幾何可變體系B. 瞬變體系C. 有一個多余約束的幾何不變體系D. 無多余約束的幾何不變體系16. 剛結(jié)點(diǎn)在結(jié)構(gòu)發(fā)生變形時的特征是（ B ）。 A. 所聯(lián)結(jié)的桿件可繞結(jié)點(diǎn)自由轉(zhuǎn)動 B. 結(jié)點(diǎn)處各桿端之間的夾角保持不變C. 結(jié)點(diǎn)處各桿端之間的夾角可以任意改變 D. 剛結(jié)點(diǎn)自身不會轉(zhuǎn)動17. 對圖示平面體系進(jìn)行幾何組成分析，該體系是（ D ）。A. 幾何可變體系B. 瞬變體系C. 有一個多余約束的幾何不變體系D. 無多余約束的幾何不變體系三、判斷1. 一體系是有n個自由度的幾何可變體系，加入n個約束后就成為無多余約束的幾何不變體系。（ 錯誤 ）2. 體系的實(shí)際自由度絕對不小于其計算自由度。（ 正確 ）3. 僅利用靜力平衡條件即可確定結(jié)構(gòu)全部反力和內(nèi)力，且解答唯一，這樣的結(jié)構(gòu)稱為靜定結(jié)構(gòu)。（ 正確）4. 如果體系的計算自由度大于零，那么體系一定時幾何可變體系。（ 正確）5. 三個剛片用三個單鉸兩兩相聯(lián)，組成的體系是無多余約束的幾何不變體系。（ 錯誤 ）6. 多余約束是體系中不需要的約束。（ 錯誤 ）7. 連接4個剛片的復(fù)鉸相當(dāng)于4個約束。（錯誤 ）8. 一個體系是有n個多余約束的幾何不變體系，那么去掉n個約束后就成為無多余約束的幾何不變體系。（ 錯誤 ）9. 鉸結(jié)點(diǎn)不僅能承受和傳遞力，而且能承受和傳遞力矩。（ 錯誤 ）10. 一個點(diǎn)在平面內(nèi)的自由度等于1。（錯誤 ）11. 兩個剛片用一個鉸和一根鏈桿相聯(lián)，組成的體系是無多余約束的幾何不變體系。（ 錯誤 ） 12. 一個體系是有n個多余約束的幾何不變體系，那么去掉n個約束后就成為無多余約束的幾何不變體系。（ 錯誤 ） 13. 剛結(jié)點(diǎn)可以承受和傳遞力，但不能承受和傳遞力矩。（ 錯誤 ） 14. 體系的實(shí)際自由度絕對不小于其計算自由度。（ 正確 ） 15. 瞬變體系在很小的荷載作用下會產(chǎn)生很大的內(nèi)力。（ 正確 ） 16. 一個點(diǎn)在平面內(nèi)的自由度等于1。（ 錯誤 ） 17. 如果在一個體系中增加一個約束，而體系的自由度并不因此減少，則稱此約束為多余約束。（ 正確 ） 18. 兩根鏈桿的約束作用相當(dāng)于一個單鉸。（ 錯誤 ） 19. 僅利用靜力平衡條件即可確定結(jié)構(gòu)全部反力和內(nèi)力，且解答唯一，這樣的結(jié)構(gòu)稱為靜定結(jié)構(gòu)。（ 正確 ） 20. 多余約束是體系中不需要的約束。（錯誤 ） Winger 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.