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學(本)形成性考核冊 作業(yè)二 一、 選擇題(每小題 2分,共 10分) 1.用力法計算超靜定結構時,其基本未知量為( D ) A 桿端彎矩 B 結點角位移 C 結點線位移 D 多余未知力 2.力法方程中的系數 ij? 代表基本體系在 1?jX 作用下產生的( C ) A iX B jX C iX 方向的位移 D jX 方向的位移 3.在力法方程的系數和自由項中( B ) A ij? 恒大于零 B ii? 恒大于零 C ji? 恒大于零 D iP? 恒大于零 4.下列哪一條不是圖乘法求位移的適用條件?( D ) A直桿 B EI為常數 C PM 、 M 至少有一個為直線形 C D FN1 FN4 FN3 FP P5F4 C FN2 FN4 FP FN4 D PM 、 M 都必須是直線形 5.下圖所示同一結構在兩種不同荷載作用下,它們之間的關系是( D ) A A點的水平位移相同 B C點的水平位移相同 C C點的水平位移相同 D BC桿變形相同 A C D B E I E A A C D B E I E A P P 二、判斷題(每小題 2分,共 10分) 1.靜定結構由于支座移動引起的位移與剛度無關。( ? ) 3.兩根鏈桿的約束作用相當于一個單鉸。 2.解:由二元體分析法 原結構是一個無多余約束的幾何不變體系。各桿 EI 相同且為常數。 ( 2)寫出位移法方程如下: k11Δ 1+ F1P= 0 ( 3)計算系數 k11 及自由項 F1P 令 EIi=12 , 則 iAB =3i, iBC =2i 作 1M 圖和 MP 圖如下: k11 = 12i+2i =14i 1P 40F=3 kN?m ( 4)求解位移法基本未知量 將系數及自由項代入位移法方程,得: 1P11140F 203k 14i 21i? ? ? ? ? ? ? ( 5)作 M 圖 基本結構 A B C Δ1 2i 1M圖 A B C 1 12i 6i 2i MP 圖( kN?m) A B C 403 403 A C 19 (20) 1.9 1.9 10kN/m 4m 6m A B C 四、 用位移法計算圖示剛架,并繪制彎矩圖。各桿 EI 相同且為常數。s largest breeding and research center. Three days are long enough for foreign visitors to visit those iconic tourist spots, he noted. The city is home to the remains of the Jin sha civilization that dates back more than 3,000 years as well as the Qing cheng Mountains and the Du jiang yan irrigation system. Qing cheng has long been recognized as the birthplace of Taoism, China39。各桿 EI=常數。 10 分) 解: 梁的懸臂 DE 為一靜定部分,可求得 MDE =36kN?m, FQDE = 24kN。( ? ) 5.力矩分配法適用于連續(xù)梁和有側移剛架。 1. 計算 C 點水平位移 解: ( 1) 作 MP 圖 ( 2) 作 M 圖 ( 3)計算 C 點水平位移 42Cx 1 2 l 1 l 1 q lq l ( )E I 3 8 2 2 4 8 E I? ? ? ? ? ? ? ? 2. 計算 C 點轉角 ( 1) MP 圖同上 ( 2) 作 M 圖 ( 3)計算 C 點轉角 32C 1 2 l 1 1 q lq l 1E I 3 8 2 2 4 E I? ? ? ? ? ? ?( ) 五、試求圖示剛架點 D 的豎向位移, EI=常數。( ? ) 9.某荷載作用下桁架可能存在零桿,它不受內力,因此在實際結構中可以將其去掉。但橫截面形狀不同,故其內力也不相同。( ? ) 5.用力法計算超靜定結構,選取的基本結構不同,則典型方程中的系數和自由項數值也不同。( ? ) 2.圖 a為一對稱結構,用位移法求解時可取半邊結構如圖 b所示。 ( 10 分) 解:計算分配系數, BABAB A B CEI3S 6μ = = 0. 42 9E I E IS + S 3 + 466???? G A B E 1M圖 1 2i 2i 4i 4i 2i A B G E 54 MP圖( kN?m) 54 A B G E M圖( kN?m) (81) A B E M圖( kN?m) (81) C D F (81) 48kN/m A B C D 6m 6m 3m 24kN 3m B C B Aμ 1 μ = 1 29 71? ? ? ? CBCBCB CDEI4S 6μ = = 0. 57 1E I E IS + S 4 + 366???? C D C Bμ 1 μ = 1 71 29? ? ? ? 分配與傳遞計算 作 M 圖。( 15 分) 解:由下圖列出體系動力學平衡方程: 對 A點取矩, 列出體系動力學平衡方程: y 3 y 3( m ) k y ( m ) 02 2 2 2lll? ? ? ? ? ? 其中: y( m )22l? 和 3y( m )2? 為慣性力, ky 為彈性力。s public security bureau shows some 100 foreign visitors enjoyed the 72hour policy by the end of March, most of them from the United States, the United Kingdom and Germany. Chengdu also reported robust growth in its overall tourist industry last year. Official statistics show that it received some 150 million tourists last year, an increase of 28 percent from 2021. Around million came from abroad, an increase of 12 percent. Total revenue from tourism surpassed 133 billion yuan ($). During his visit to Kazakhstan in September, Chinese President Xi Jinping proposed that China and Central Asia join hands to build a Silk Road economic belt to boost cooperation. The idea has been w idely echoed in Central Asian countries, being an encouraging blueprint for Chinese areas along the Silk Road that has linked Asia and Europe for more than 2,000 years. In the next three w eeks, China Daily reporters will travel through the belt in China and in Kazakhstan, Uzbekistan and Turkey. They w ill show the progress and expectations of the countries, businesses and peoples on the route. Shaanxi the start of the ancient Silk Road has positioned itself as the new starting point for the development of the Silk Road Economic Belt, w hich will strengthen China39。 ( 10 分) A B C K ? 1 MK影響線 ? 1 A B C ? 1/2 FRA影響線 ? 1 2m 2m A B C 2m K 解: 用機動法作 影響線 如下: 五、 作圖示 梁 FyA、 MC的 影響線,并利用影響線