【正文】
12176。包括鋼軌、道碴、軌枕、防水層、保護(hù)層、人行道遮板、聲屏障、擋碴 墻、電纜槽豎墻、蓋板等重量,直線梁按184kN/m計(jì)算,曲線梁按198kN/m計(jì)算。先計(jì)算四個(gè)支座的支座反力,再把荷載計(jì)算到承臺(tái)底面形心處。橋上有車時(shí)按上式值的80%計(jì)算。圖7 單孔輕載時(shí)承臺(tái)底面受力簡圖2. 基礎(chǔ)的選擇與檢算(1) 選定樁基類型考慮樁基為低承臺(tái),采用鉆孔灌入樁,確定設(shè)計(jì)為端承樁。d) 估算樁數(shù):(按雙孔重載估算) 估算公式:式中:—豎向承載力總和(kN);R—基樁的豎向承載力設(shè)計(jì)值;—經(jīng)驗(yàn)系數(shù)。由教材表57查得樁的極限端阻力標(biāo)準(zhǔn)值為:強(qiáng)分化砂巖:h=25m,取=6300kPa。(4) 樁與承臺(tái)連接方式采用主筋伸入式,樁伸入承臺(tái)板內(nèi)10cm,具體配筋見后面詳述。首先求出承臺(tái)內(nèi)區(qū)、外區(qū)的凈面積 和承臺(tái)底地基土凈面積 可根據(jù)由表521內(nèi)插法查得,由于承臺(tái)下的砂粘土屬于高壓縮性土,故按取值。(8) 水平承載力檢驗(yàn)水平力H=34kN,水平力和豎向力的合力與鉛垂線的夾角,故可以不驗(yàn)算基樁的水平承載力。設(shè)計(jì)一級(jí)樁基,由于在x方向,在y方向。墩身埋于土中高度:∴可以用m法直接查表計(jì)算d) 樁身截面配筋設(shè)計(jì)(一孔重載)i. 樁身彎矩計(jì)算 ∴任意深度z處樁身截面彎矩:列表計(jì)算如下:0 010 00 由表知: ii. 計(jì)算偏心距初始偏心距:偏心距放大系數(shù):其中,影響系數(shù)計(jì)算長度:,(為變形系數(shù)) 主力+附加力,所以K=則∴ 3. 基礎(chǔ)配筋根據(jù)灌注樁構(gòu)造要求,橋梁樁基主筋宜采用光圓鋼筋,主筋直徑不宜小于16mm,凈距不宜小于120mm,且任一情況下不得小于80mm,主筋凈保護(hù)層不應(yīng)小于60mm。箍筋采用Φ8200mm,為增加鋼筋籠剛度,順鋼筋籠長度每隔2m加一道φ18的骨架鋼筋。420mm)。六、規(guī)范及參考書1.中華人民共和國國家標(biāo)準(zhǔn).建筑地基基礎(chǔ)設(shè)計(jì)規(guī)范,GB 50007—20022.中華人民共和國鐵道部標(biāo)準(zhǔn).鐵路橋涵地基基礎(chǔ)設(shè)計(jì)規(guī)范,TBJ2-993.趙明華主編,徐學(xué)燕副主編.基礎(chǔ)工程.高等教育出版社,20034.李克釧主編,羅書學(xué)副主編.基礎(chǔ)工程.中國鐵道出版社,2000附錄:外文翻譯In Wang Zuoliang’s translation practices, he translated many poems, especially the poems written by Robert Burns. His translation of Burn’s “A Red, Red Rose” brought him fame as a verse translator. At the same time, he published about ten papers on the translation of poems. Some argue that poems cannot be translated. Frost stresses that poetry might get lost in translation. According to Wang, verse translation is possible and necessary, for “The poettranslator brings over some exciting work from another culture and in doing so is also writing his own best work, thereby adding something to his culture. In thi