【正文】 矩圖 見圖 1（ f）、 2M 見圖 1（ g）、荷載彎矩圖 MP 見圖 1（ e）。 用力法計(jì)算圖示結(jié)構(gòu)的彎矩，并繪 圖示結(jié)構(gòu)的 M圖， EI=常數(shù)。 解： 二次超靜定，基本結(jié)構(gòu)如圖： 列力法方程 ????? ???? ???? 0022221211212111pp???? ???? 圖作 p，MM，M 21 求 11? 、 12? 、 22? 、 21? 、 p1? 、 p2? EIEI 366323621111 ???????? EIEI 1086662112112 ??????? ?? EIEI 28866646621122 ??????? ???????? EIEIP 45023602133602111 ???????? ?????????? EIEIP 54063602112 ???????? ?????? 求得144572521?????? 作 M圖 pMxMxMM ??? 2211 。 EI=常數(shù)。 EI=常數(shù)。 解： 一次超靜定結(jié)構(gòu)，基本結(jié)構(gòu)如圖 列力法方程 01111 ??? px? 作 圖作 p，MM1 求 11? 、 p1? EIEIEI 66255552 13255521111 ???????????? EIEIP 12510552 11 ???????? 求 1? , ?? 作 M圖 pMxMM ?? 11 注：務(wù)必掌握例 22 位移法計(jì)算舉例 計(jì)算圖示結(jié)構(gòu)位移法典型方程式中的系數(shù)和自由項(xiàng)。 P P A = I/ l 2 I I l Z 1 l /2 l /2 l /2 l /2 165,1611,0,163 PQpQMplM BAfABfBAfABf ??????。 16kN 參考答案：只有一個(gè)結(jié)點(diǎn)角位移。 位移法方程： 01111 ?? PRzr . 如圖 14所示，繪彎矩圖。 1）建立基本結(jié)構(gòu)如圖 15 所示。 1） 如圖 14所示，繪彎矩圖。 1）建立基本結(jié)構(gòu)如圖 21 所示。 圖 21 基本結(jié)構(gòu) 圖 22 1M 圖 23 PM 圖 24 用位移法計(jì)算圖 26示結(jié)構(gòu)，并做彎矩圖。 （具有兩個(gè)結(jié)點(diǎn)位移結(jié)構(gòu)的計(jì)算） 解： 1）此結(jié)構(gòu)有兩個(gè)結(jié)點(diǎn)位移，即結(jié)點(diǎn) B 的角位移及結(jié)點(diǎn) E 的水平線位移。此時(shí)原結(jié)構(gòu)變成四根超靜定桿的組合體。 令lEIi? 8908983015312610343212222211211??????????????????qqlRRliliirlirriiiirPP 圖 29 3m 3m 3m 10kN /m 圖 26 圖 28 1M 圖 27 基本體系 圖 31 pM 將求得的各系數(shù)及自由項(xiàng)代入位移法方程 ??? ?? EIZ EIZ / / 4）彎矩疊加公式為： PMZMZMM ??? 2211 利用彎矩疊加公式求得各控制截面彎矩為： ? ?? ?mkNiZMmkNZiMmkNZliiZMmkNZliZiMmkNZliMCECBCDDA???????????????????????6462.89031121212 計(jì)算圖示結(jié)構(gòu)位移法典型議程式中系數(shù) r12和自由項(xiàng) R1p（各桿的 EI 為常數(shù)） 圖 30 圖 32M 用位移法作圖示結(jié)構(gòu) M圖。 解： 解： piPPPPMMMM、iqlqli，F(xiàn)k、Fk、MM、Fk、????????????1312111111111111556,81743021圖作并求求圖作列位移法方程基本體系如圖量該結(jié)構(gòu)有三個(gè)基本未知 用位移法計(jì)算圖示的剛架。 解： 只有一個(gè)結(jié)點(diǎn)角位移，基本結(jié)構(gòu)如圖所示 列位移法方程（令 iEI?5） 01111 ??? pFk 作 圖作 p，MM1 求 11k 、 pF1 ，并求 1? iiiik 1464411 ???? 61251 ?pF EIi 84625841251 ????? 作 M圖 PMMM ??? 11 7. 用位移法計(jì)算圖示剛架，畫 M圖。 解： 只有一個(gè)結(jié)點(diǎn)角位移，基本結(jié)構(gòu)如圖所示 列位移法方程 01111 ??? pFk 圖作 p，MM1 求 11k 、 pF1 ，并求 1? ik 711? 4251 ??pF i28251 ?? 作 M圖 PMMM ??? 11 ，畫 M圖 。各桿 EI 相同等于常數(shù)。 判斷所示體系的動(dòng)力自由度。 動(dòng)力自由度為 1 一． 求圖示兩跨連續(xù)梁的極限荷載。 只有一個(gè)破壞機(jī)構(gòu)，如圖所示。 對(duì) BD段：uuuuB qMxMxqM 2,0221,0 2 ????? 對(duì) DC段： ? ?22,0 xl MqM uuC ???? 求解上述兩個(gè)方程有： ? ?,22 lMqlx uu ??? Visafree policy brings Chengdu biz, tourism boost. Making national headlines several times, Chengdu39。s level of internationalization. The policy will also bring direct economic revenue, Li said. Chengdu has many cultural legacies and is also a paradise for panda lovers with the world39。s ancient indigenous religion, while Du jiang yan is considered to be the oldes t functioning watercontrol project in the world. Chengdu ranked third in tourist facilities, management and services among 60 Chinese cities in a customer satisfaction survey released last year. But, Li added that efforts are still needed to develop more touris m products, improve English services and provide accurate translation of traffic signs and scenic billboards. Zhao Yun, chairwoman of British Chamber of Commerce Southwest China, told China Daily that his colleagues found the policy very convenient. A Britis h client once flew here and stayed for just one day to check her ordered goods, she said. Zhao was born in Shanxi province, but she has lived in Chengdu for more than 1 0 years. My life was like a running race moving from place to place. I also lived in Beijing and Shanghai before, she said. But Chengdu is a place that you never want to leave once settling down. It is now my second hometown, she said. If the environment is further improved, the city will attract more people to visit and live, with the 72hour visafree policy and pelling conditions in transportation, culture, climate and cuisine, he said. Foreigners also gave positive feedback on the policy. A spokesman from Dell Inc said the pany has a global hub of operation in Chengdu, so the threeday visa has an immediate and positive influence on the pany39。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 2020. Around million came from abroad, an increase of 12 percent. Total revenue from touris m 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 widely 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 weeks, China Daily reporters will travel through the belt in China and in Kazakhstan, Uzbekistan and Turkey. They will 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, which will strengthen China39。an. Lou held a joint interview with 27 media, including China Daily,