【文章內(nèi)容簡介】 筋端部的錨具來傳遞的。（ ） 5．我國混凝土結(jié)構(gòu)設計規(guī)范規(guī)定，預應力混凝土構(gòu)件的混凝土強度等級不應低于 C30。對采用鋼絞線、鋼絲、熱處理鋼筋作預應力鋼筋的構(gòu)件，特別是大跨度結(jié)構(gòu)，混凝土強度等級不宜低于 C40。（ √ ） 6． 張拉控制應力是指預應力鋼筋在進行張拉時所控制達到的最大應力值。 ( √ ) 7．為保證鋼筋與混凝土的粘結(jié)強度，防止放松預應力鋼筋時出現(xiàn)縱向劈裂 裂縫，必須有一定的混凝土保護層厚度。（ √ ） 8．我國 《公路橋規(guī)》采用以概率論為基礎的極限狀態(tài)設計法，按分項系數(shù)的設計表達式進行設計，對橋梁結(jié)構(gòu)采用的設計基準期為 50年。（ ） 9． 與《房建規(guī)范》不同，《公路橋規(guī)》在抗剪承載力計算中，其混凝土和箍筋的抗剪能力 csV 沒有采用兩項相加的方法，而是采用破壞斜截面內(nèi)箍筋與混凝土的共同承載力。 ( √ ) 10．《公路橋規(guī)》規(guī)定受壓構(gòu)件縱向鋼筋面積不應小于構(gòu)件截面面積的 %。（ √ ） 11．我國《公路橋規(guī)》關于裂縫寬度的計算與 《混凝土結(jié)構(gòu)設計規(guī)范》 是相同的。（ ） 12. 我國 《公路橋規(guī)》中指出裂縫寬度主要與受拉鋼筋應力、鋼筋直徑、受拉鋼筋配筋率、鋼筋表面形狀、混凝土標號和保護層厚度有關，而撓度的計算則根據(jù)給定的構(gòu)件剛度用結(jié)構(gòu)力學的方法計算。（ √ ） 三、 簡答題 1．與普通混凝土相比，預應力混凝土具有哪些優(yōu)勢和劣勢？ 答：與普通混凝土相比，預應力混凝土具有優(yōu)勢 是： 1）構(gòu)件的抗裂度和剛度提高； 2）構(gòu)件的耐久性增加； 3）自重減輕； 4）節(jié)約材料。 與普通混凝土相比，預應 力混凝土具有 劣 勢 是： 預應力混凝土 施工需要專門的材料和設備、特殊的工藝、造價較高。 2．簡述有粘結(jié)預應力與無粘結(jié)預應力的區(qū)別？ 答：有粘結(jié)預應力 ，是指沿預應力筋全長其周圍均與混凝土粘接、握裹在一起的預應力。先張預應力結(jié)構(gòu)及預留孔道穿筋壓漿的后張預應力結(jié)構(gòu)均屬此類。 無 粘結(jié)預應力 ，是指預應力筋伸縮、滑動自由，不與周圍混凝土粘接的預應力。無 粘結(jié)預應力 混凝土結(jié)構(gòu)通常與后張預應力工藝相結(jié)合。 3．列舉三種建筑工程中常用的預應力錨具？ 答： 螺絲端桿錨具、錐形錨具、鐓頭錨具、夾具式錨具。 4．預應力混凝土結(jié)構(gòu) 及 構(gòu)件所用 的混凝土，需滿足哪些要求？ 答： 預應力混凝土結(jié)構(gòu)構(gòu)件所用的混凝土，需滿足下列要求： 1）強度高。與普通鋼筋混凝土不同，預應力混凝土必須采用強度高的混凝土。因為強度高的混凝土對采用先張法的構(gòu)件可提高鋼筋與混凝土之間的粘結(jié)力，對采用后張法的構(gòu)件，可提高錨固端的局部承壓承載力。 2）收縮、徐變小。以減少因收縮、徐變引起的預應力損失。 3）快硬、早強?？杀M早施加預應力，加快臺座、錨具、夾具的周轉(zhuǎn)率，以利加快施工進度。 5． 引起預應力損失的因素有哪些？如何減少各項預應力損失？ 答：引起預應力損失的因素主要 有錨固回縮損失、摩擦損失、溫差損失、應力松弛損失、收縮徐變損失等。 見教材 P216220 6．公路橋涵按承載力極限狀態(tài)和正常使用極限狀態(tài)進行結(jié)構(gòu)設計，在設計中應考慮哪三種設計狀況？分別需做哪種設計？ 答：公路橋涵按承載力極限狀態(tài)和正常使用極限狀態(tài)進行結(jié)構(gòu)設計，在設計中應考慮 以下 三種設計狀況 ： 1）持久狀態(tài)。該狀態(tài)需要作承載力極限狀態(tài)和正常使用極限狀態(tài)設計。 2）短暫狀態(tài)。該狀態(tài)主要做承載力極限狀態(tài)設計，必要時才作正常使用極限狀態(tài)設計。 3）偶然狀態(tài)。該狀態(tài)僅作承載力極限狀態(tài)設計。 四、 計算題 1．已知一矩形截面簡支梁，截面尺寸 b h=200mm550mm ，混凝土強度等級為 C25，縱向鋼筋采用 HRB335級，安全等級為二級，梁跨中截面承受的最大彎矩設計值為 M=160kNm 。 ① 若上述設計條件不能改變，試進行配筋計算。 ② 若由于施工質(zhì)量原因，實測混凝土強度僅達到 C20，試問按 ① 問所得鋼筋面積的梁是否安全？ MPafcd ? ， MPafsd 280? ， ?b? ， 0 ? ? 假設 40sa? mm，則有效高度 mmhh 51040550400 ????? 。 （ 1）計算受壓區(qū)高度 x 2 000 2 dcdMx h h fb?? ? ? mmhmm b 8 55 1 6 22 0 101 6 1 05 1 0062????????????? （ 2）計算鋼筋數(shù)量 sA mmf bxfAsdcds ????? （ 3）選擇并布置鋼筋 選用 3 25（ )1473 2mmAs ? ，鋼筋布置如圖所示。 （ 4）驗算配筋率 實際配筋率 % 30 ???? bhA s? % ?? 。 請您刪除一下內(nèi)容， O(∩ _∩ )O 謝謝！?。　?China39。s 10 mustsee animations】 The Chinese animation industry has seen considerable growth in the last several years. It went through a golden age in the late 1970s and 1980s when successively brilliant animation work was produced. Here are 10 mustsee classics from China39。s animation outpouring that are not to be missed. Let39。s recall these colorful images that brought the country great joy. Calabash Brothers Calabash Brothers (Chinese: 葫蘆娃 ) is a Chinese animation TV series produced by Shanghai Animation Film Studio. In the 1980s the series was one of the most popular animations in China. It was released at a point when the Chinese animation industry was in a relatively downed state pared to the rest of the international munity. Still, the series was translated into 7 different languages. The episodes were produced with a vast amount of papercut animations. Black Cat Detective Black Cat Detective (Chinese: 黑貓警長 ) is a Chinese animation television series produced by the Shanghai Animation Film Studio. It is sometimes known as Mr. Black. The series was originally aired from 1984 to 1987. In June 2021, a rebroadcasting of the original series was announced. Critics bemoan the series39。 violence, and lack of suitability for children39。s education. Proponents of the show claim that it is merely for entertainment. Effendi Effendi, meaning sir and teacher in Turkish, is the respectful name for people who own wisdom and knowledge. The hero39。s real name was Nasreddin. He was wise and witty and, more importantly, he had the courage to resist the exploitation of noblemen. He was also full of passion and tried his best to help poor people. Adventure of Shuke and Beita【舒克與貝塔】 Adventure of Shuke and Beita (Chinese: 舒克和貝塔 ) is a classic animation by Zheng Yuanjie, who is known as King of Fairy Tales in China. Shuke and Beita are two mice who don39。t want to steal food like other mice. Shuke became a pilot and Beita became a tank driver, and the pair met accidentally and became good friends. Then they befriended a boy named Pipilu. With the help of PiPilu, they cofounded an airline named Shuke Beita Airlines to help other animals. Although there are only 13 episodes in this series, the content is very pact and attractive. The animation shows the preciousness of friendship and how people should be brave when facing difficulties. Even adults recalling this animation today can still feel touched by some scenes. Secrets of the Heavenly Book Secrets of the Heavenly Book, (Chinese: 天書奇談 ) also referred to as Legend of the Sealed Book or Tales about the Heavenly Book, was released in 1983. The film was produced with rigorous dubbing and fluid bination of music and vivid animations. The story is based on the classic literature Ping Yao Zhuan, meaning The Suppression of the Demons by Feng Menglong. Yuangong, the deacon, opened the shrine and exposed the holy book to the human world. He carved the book39。s contents on the stone wall of a white cloud cave in the mountains. He was then punished with guarding the book for life by the jade emperor for breaking heaven39。s law. In order to pass this holy book to human beings, he would have to get by the antagonist fox. The whole animation is characterized by charming Chinese painting, including pavilions, ancient architecture, rippling streams and crowded markets, which fully demonstrate the unique beauty of China39。s natural scenery. Pleasant Goat and Big Big Wolf【喜洋洋與灰太狼】 Pleasant Goat and Big Big Wolf (Chinese:喜羊羊與灰 太狼 ) is a Chinese animated television series. The show is about a group of goats living on the Green Pasture, and the story revolves around a clumsy wolf who wants to