混凝土大壩外文翻譯--混凝土重力壩的設(shè)計(jì)分析與比較(存儲(chǔ)版)
【正文】 oncrete gravity dams are based on design earthquakes and sitespecific motions determined from seismological eva luation. At a minimum, a seismological evaluation should be performed on all pro jects located in seismic zones 1, 2, and 3 of Bangladesh [8], depending upon the severity of earthquakes. The seismic coefficient method of analysis should be used in determining the resultant location and sliding stability of dams. In strong seismicity areas, a dynamic seismic analysis is required for the internal stress analysis. . Effect of Vertical Acceleration (ɑv) A vertical acceleration may either act downward or upward. When it acts in the upward direction, then the foundation of the dam will be lifted upward and bees closer to the body of the dam, and thus the effective weight of the dam will increase and hence, the stress developed will increase. When the vertical acceleration acts downward, the foundation shall try to move downward away from the dam body。 2) Headwater and tailwater pressures。 7) Earth quake forces。垂直使用 獲得的剪切應(yīng)力與使用二維重心法得到的比較，發(fā)現(xiàn)比較少，以 2D 重心法，除了在重力壩 壩趾主應(yīng)力 。這兩種一般混 凝土施工方法在混凝土重力壩是為常規(guī)放置大體積混凝土和碾壓混凝土。 高混凝土重力壩的典型橫截面正如圖所示，它的上游面可能與大壩的某段長度保持垂直或部分傾斜。上下游的水壓力 。波浪的拍擊壓力 1地基的反應(yīng)。 揚(yáng)壓力 水通過空隙滲流，基礎(chǔ)材料的裂紋和裂縫，壩體滲水，然后通過壩體和壩基之間對(duì)大壩產(chǎn)生壓力，根據(jù) 6，壩體和壩基之間的壓力強(qiáng)度應(yīng)該等于各自的靜水 壓力和直線連接的強(qiáng)度坐標(biāo)，為了緩解排水廊道上升，廊道表面的靜水壓力應(yīng)等于根部和頂部靜水壓力的 1/3。由于地震加速度可能發(fā)生在任何方向，完成時(shí)最不順的方向應(yīng)該被分析考慮進(jìn)去。這樣就減輕了大壩的實(shí)際重量和破壞大壩的穩(wěn)定性。這種慣性力的產(chǎn)生是為了保證壩 體和壩基不分離。）這個(gè)力也會(huì)產(chǎn)生最糟糕的結(jié)果。由【 9】可知，水力的大小可以通過（ 3）式來計(jì)算 27 2 HkCp whme ?? （ 3） 在這個(gè)式子中 Cm等于含有已知不變斜率的壓力系數(shù)的最大值，這里的 Q是角度，是由大壩朝向上游的一面和水平加速度形成的。當(dāng)垂直加速度向上時(shí)，大壩的壩基就會(huì)被抬上來，靠近大壩的壩體，這樣大壩的實(shí)際重量就會(huì)增加，因此，形成的壓力也會(huì)增加。在極端的地震帶，用保守的設(shè)計(jì)，甚至有時(shí)一個(gè) 的值都可能被接受。水平水壓力通過存儲(chǔ)在大壩的上游側(cè)和下游側(cè)水的重量來施加。風(fēng)的壓力 。 2 負(fù)載 在混凝土重力壩的設(shè)計(jì)中，準(zhǔn)確計(jì)算出荷載的穩(wěn)定性和壓力力分析是非常重要的。當(dāng)在合適條件的情況下，這樣的大壩可以被構(gòu)建很高的高度。這種類型的結(jié)構(gòu)是非常耐用的，并且只需要很少的維護(hù)。并采用二維分析重心法和有限元法分析其穩(wěn)定 性和應(yīng)力條件。 5) Earth and silt pressures。 4) Temperature。 kh = fraction of gravity adopted for horizontal acceleration such as αh=khg The moment of this force about the base is given by (4) 2) Horizontal Inertia Force: In addition to exerting the hydrodynamic pressure, the horizontal acceleration produces an inertia force into the body of the dam. This force is generated to keep the body and the foundation of the dam together as one piece. The direction of the produced force will be opposite to the accele ration imparted by the earthquake. Since an earthquake may impart either upstream or downstream acceleration, it is needed to choose the direction of this force in the stability analysis of dam structure in such a way that it produces most unfavorable effects under the consid ered conditions. For example, when the reservoir is full, this force will produce worst results if it is additive to the hydrostatic water pressure, thus Acting towards the downstream (., when upstream earthquake acceleration towards the reservoir is produced). When the reservoir is empty, this force would produce worst results, if considered to be acting upstream ( earthquake acceleration moving towards the downstream is produced. 原文出自：
畢業(yè)設(shè)計(jì)相關(guān)推薦
鄂ICP備17016276號(hào)-1