【正文】 ........................... 7 孔跨布置 .......................................................................................................................... 7 主要設(shè)計技術(shù)參數(shù)和標準 .............................................................................................. 8 交通參數(shù) ....................................................................................................................... 8 公路設(shè)計技術(shù)標準 ......................................................................................................... 8 主要材料 ....................................................................................................................... 8 箱形梁構(gòu)造形式及相關(guān)設(shè)計參數(shù) .................................................................................. 9 橫截面尺寸 .................................................................................................................... 9 箱梁底板厚度和腹板寬度 ..............................................................................................10 第四章 主梁作用效應(yīng)計算 .................................................................................................... 11 永久作用集度 ................................................................................................................ 11 一期永久作用集度（主梁自重） ................................................................................... 11 二期永久作用集度 ........................................................................................................ 11 II 永久作用效應(yīng) ................................................................................................................ 11 可變作用效應(yīng)計算 ........................................................................................................ 12 沖擊系數(shù)和車道折減系數(shù)計算 .......................................................................................12 橫向分布系數(shù)計算 ........................................................................................................13 可變荷載作用效應(yīng)計算 .................................................................................................16 主梁作用效應(yīng)組合 ........................................................................................................ 20 第五章 預(yù)應(yīng)力鋼束估算及布置 ............................................................................................ 23 預(yù)應(yīng)力鋼筋數(shù)量估算 .................................................................................................... 23 預(yù)應(yīng)力鋼筋布置 ............................................................................................................ 23 跨中截面及錨固段截面的鋼束位置 ................................................................................23 鋼束彎起角度及線形的確定 ..........................................................................................24 鋼束計算 ......................................................................................................................24 第六章 計算主梁截面幾何特性 ............................................................................................ 28 第七章 預(yù)應(yīng)力損失計算 ........................................................................................................ 29 預(yù)應(yīng)力鋼束與管道壁之間的摩擦引起的預(yù)應(yīng)力損失 ................................................ 29 由錨具變形、鋼束回縮引起的預(yù)應(yīng)力損失 ................................................................ 30 預(yù)應(yīng)力鋼筋分批張拉時混凝土彈性壓縮引起的應(yīng)力損失 ....................................... 31 鋼筋松弛引起的預(yù)應(yīng)力損失 ........................................................................................ 31 混凝土收縮、徐變引起的預(yù)應(yīng)力損失 ........................................................................ 31 鋼束預(yù)應(yīng)力損失匯總 .................................................................................................... 33 第八章 承載力、應(yīng)力、撓度、抗裂性驗算 ...................................................................... 34 持久狀況承載能力極限狀態(tài)驗算 ................................................................................ 34 跨中正截面承載力驗算 .................................................................................................34 斜截面承載力驗算 ........................................................................................................35 應(yīng)力驗算 ........................................................................................................................ 37 短暫狀況構(gòu)件的應(yīng)力驗算 ..............................................................................................37 持久狀況構(gòu)件的應(yīng)力驗算 ..............................................................................................40 抗裂性驗算 .................................................................................................................... 43 作用短期效應(yīng)組合作用下的正截面抗裂驗算 ..................................................................43 作用短期效應(yīng)組合作用下的斜截面抗裂驗算 ..................................................................43 III 主梁變形（撓度）驗算 ................................................................................................ 44 預(yù)加力引起的跨中反拱度 ..............................................................................................44 荷載引起的跨中撓度 .....................................................................................................44 預(yù)拱度的設(shè)置 ...............................................................................................................45 局部承壓驗算 ................................................................................................................ 45 局部承壓區(qū)的截面尺寸驗算 ..........................................................................................45 局部抗壓承載力驗算 .....................................................................................................46 第九章 行車道板計算 ............................................................................................................ 47 懸臂板荷 載效應(yīng)計算 ................................................................................................... 47 連續(xù)板荷載效應(yīng)計算 .........................................................................................