芒果视频下载

簡介

銀(yin)盤水(shui)(shui)(shui)(shui)(shui)(shui)電(dian)站(zhan)正常(chang)蓄(xu)水(shui)(shui)(shui)(shui)(shui)(shui)位(wei)(wei)215m，死水(shui)(shui)(shui)(shui)(shui)(shui)位(wei)(wei)211.5m，保(bao)證出力161.7MW，裝機(ji)(ji)容(rong)量600MW，多年平(ping)均(jun)發(fa)電(dian)量27.08億kW/h，庫水(shui)(shui)(shui)(shui)(shui)(shui)位(wei)(wei)每天(tian)在(zai)正常(chang)蓄(xu)水(shui)(shui)(shui)(shui)(shui)(shui)位(wei)(wei)215m和死水(shui)(shui)(shui)(shui)(shui)(shui)位(wei)(wei)211.5m之間變(bian)(bian)化。銀(yin)盤水(shui)(shui)(shui)(shui)(shui)(shui)電(dian)站(zhan)水(shui)(shui)(shui)(shui)(shui)(shui)輪機(ji)(ji)正常(chang)運(yun)行(xing)水(shui)(shui)(shui)(shui)(shui)(shui)頭(tou)(tou)(tou)范(fan)(fan)圍(wei)為(wei)13～35.12m，加權平(ping)均(jun)水(shui)(shui)(shui)(shui)(shui)(shui)頭(tou)(tou)(tou)為(wei)29.66m，額定(ding)水(shui)(shui)(shui)(shui)(shui)(shui)頭(tou)(tou)(tou)26.5m。其(qi)運(yun)行(xing)水(shui)(shui)(shui)(shui)(shui)(shui)頭(tou)(tou)(tou)屬低水(shui)(shui)(shui)(shui)(shui)(shui)頭(tou)(tou)(tou)且(qie)水(shui)(shui)(shui)(shui)(shui)(shui)頭(tou)(tou)(tou)變(bian)(bian)幅較(jiao)(jiao)大，該水(shui)(shui)(shui)(shui)(shui)(shui)頭(tou)(tou)(tou)是軸流轉槳(jiang)式(shi)機(ji)(ji)型較(jiao)(jiao)理想的(de)運(yun)行(xing)范(fan)(fan)圍(wei)。軸流轉槳(jiang)式(shi)水(shui)(shui)(shui)(shui)(shui)(shui)輪機(ji)(ji)具有效率曲(qu)線(xian)平(ping)坦、單(dan)位(wei)(wei)轉速高、穩定(ding)運(yun)行(xing)區(qu)域較(jiao)(jiao)寬(kuan)廣等(deng)優點，適用(yong)于低水(shui)(shui)(shui)(shui)(shui)(shui)頭(tou)(tou)(tou)段且(qie)水(shui)(shui)(shui)(shui)(shui)(shui)頭(tou)(tou)(tou)變(bian)(bian)幅大的(de)電(dian)站(zhan)。經綜合分析(xi)比較(jiao)(jiao)，本(ben)電(dian)站(zhan)選用(yong)軸流轉槳(jiang)式(shi)水(shui)(shui)(shui)(shui)(shui)(shui)輪發(fa)電(dian)機(ji)(ji)組(zu)方案(an)。

烏江銀盤水(shui)電(dian)(dian)(dian)站(zhan)由重慶大唐國際武隆(long)(long)水(shui)電(dian)(dian)(dian)開發(fa)有限公司負責建設和運營管理，目前，前3臺機組已投(tou)產發(fa)電(dian)(dian)(dian)，第(di)4臺機組也將于2011年(nian)底前投(tou)產發(fa)電(dian)(dian)(dian)。4臺機組全部投(tou)產運行后，每年(nian)將有30億千瓦時電(dian)(dian)(dian)量并入(ru)重慶電(dian)(dian)(dian)網(wang)，可緩解(jie)重慶市電(dian)(dian)(dian)力緊張局面，并增加武隆(long)(long)、彭水(shui)兩縣(xian)的財政收入(ru)，帶動(dong)地(di)區經濟(ji)發(fa)展。

工程技術

按(an)照工程(cheng)(cheng)總(zong)體施工計(ji)劃安排，導流明(ming)渠混(hun)凝土(tu)(tu)縱(zong)向(xiang)(xiang)圍(wei)堰(yan)在2007年8月底完(wan)工，該圍(wei)堰(yan)需從(cong)高(gao)程(cheng)(cheng)172m澆至堰(yan)頂(ding)217m,共(gong)上升45m,其中高(gao)程(cheng)(cheng)184m以下(xia)為常態混(hun)凝土(tu)(tu)，高(gao)程(cheng)(cheng)184m以上為碾壓混(hun)凝土(tu)(tu)，本工程(cheng)(cheng)各類(lei)混(hun)凝土(tu)(tu)38.08萬(wan)立方米(mi),混(hun)凝土(tu)(tu)月高(gao)峰期(qi)強度9.2萬(wan)立方米(mi)/月,混(hun)凝土(tu)(tu)小時高(gao)峰期(qi)強度280立方米(mi)/h，由于(yu)各種客觀原因(yin)，工期(qi)滯后，為了確保該工程(cheng)(cheng)按(an)期(qi)完(wan)成，黃河勘測規劃設(she)計(ji)有限公司(si)項(xiang)目監理部、重(zhong)慶國際水電開發公司(si)項(xiang)目工程(cheng)(cheng)部、以及中國水電十四局項(xiang)目部針對(dui)碾壓混(hun)凝土(tu)(tu)縱(zong)向(xiang)(xiang)圍(wei)堰(yan)快(kuai)速施工方案作(zuo)了深(shen)入細致的研究，并(bing)組織(zhi)技術人員到外地(di)考(kao)察學(xue)習(xi)，提出了采用(yong)大(da)倉面(mian)斜層鋪(pu)筑法并(bing)取得了良(liang)好的效果。

該技術將碾壓層(ceng)(ceng)由(you)平層(ceng)(ceng)改為1∶10～1∶20的斜層(ceng)(ceng)，斜層(ceng)(ceng)鋪(pu)筑法的具體做法是(shi)：開倉(cang)(cang)段先平層(ceng)(ceng)鋪(pu)筑，且鋪(pu)筑層(ceng)(ceng)自下而上依次遞加，使新澆筑的混凝土表面(mian)形(xing)成(cheng)一(yi)個斜面(mian)，至收(shou)倉(cang)(cang)端大(da)部分混凝土按此斜面(mian)鋪(pu)筑，收(shou)倉(cang)(cang)段通(tong)過(guo)幾個依次加長的平層(ceng)(ceng)收(shou)倉(cang)(cang)，即(ji)平層(ceng)(ceng)段、斜層(ceng)(ceng)段、平層(ceng)(ceng)段三部分組(zu)成(cheng)（見(jian)圖(tu)1）。

避免在坡(po)(po)腳(jiao)部位(wei)(wei)形(xing)成薄(bo)層(ceng)(ceng)尖(jian)腳(jiao)和嚴格(ge)處理二次污染是保(bao)證(zheng)斜層(ceng)(ceng)鋪(pu)筑(zhu)法施工(gong)質量的(de)兩個主要問(wen)題，因薄(bo)層(ceng)(ceng)尖(jian)腳(jiao)部位(wei)(wei)骨料(liao)易被壓(ya)碎，在坡(po)(po)腳(jiao)部位(wei)(wei)應(ying)由人工(gong)清理骨料(liao)，清除坡(po)(po)腳(jiao)處厚度小(xiao)于10～20cm尖(jian)腳(jiao)部位(wei)(wei)。其施工(gong)工(gong)藝(yi)流(liu)程同平(ping)層(ceng)(ceng)鋪(pu)筑(zhu)法一致(zhi)，在此不(bu)再贅述(shu)。

特殊氣象條件下施工

高(gao)溫條件下的碾壓混凝土(tu)施工

高溫(wen)天(tian)氣施工，保(bao)證施工質量最根(gen)本的途徑是(shi)大(da)幅度削減層(ceng)間(jian)間(jian)隔時(shi)(shi)間(jian)，同時(shi)(shi)采用控制和(he)補償表面水分蒸(zheng)發散失的措(cuo)施。斜層(ceng)鋪(pu)筑法，人為縮小澆筑面積，大(da)幅度削減層(ceng)間(jian)間(jian)隔時(shi)(shi)間(jian)，對混凝(ning)土的層(ceng)面結合質量和(he)抗剪能(neng)力都有可(ke)靠保(bao)證。

（1）施工倉面(mian)覆(fu)蓋(gai)

高溫條(tiao)件下(xia)，采用保(bao)溫被對(dui)倉(cang)面及時(shi)進行覆(fu)蓋，不僅可以起到保(bao)溫保(bao)濕的作用，還(huan)可以延緩(huan)碾壓混凝土(tu)(tu)的初凝時(shi)間，減小VC值的增加，同時(shi)對(dui)運輸車輛(liang)設置遮陽遮雨棚，以降低(di)暴雨對(dui)混凝土(tu)(tu)拌和物含水量的影(ying)響。

（2）施工倉面(mian)噴霧

噴(pen)霧(wu)降溫(wen)是(shi)夏季高溫(wen)施(shi)(shi)工的(de)(de)重(zhong)要質量保證(zheng)措施(shi)(shi)之(zhi)一。本(ben)工程倉(cang)(cang)面(mian)安設4臺(tai)噴(pen)霧(wu)機，同時配有沖(chong)毛槍，對攤鋪(pu)的(de)(de)混凝土表面(mian)不斷噴(pen)霧(wu)，效果較好(hao)，未(wei)發現(xian)(xian)失水變白，結硬現(xian)(xian)象。若(ruo)噴(pen)霧(wu)效果良(liang)好(hao)，可降低(di)倉(cang)(cang)面(mian)溫(wen)度(du)(du)3℃左右(you)，減小(xiao)了(le)溫(wen)度(du)(du)倒(dao)灌，營造了(le)適宜澆筑的(de)(de)倉(cang)(cang)面(mian)小(xiao)氣候(hou)。國內(nei)(nei)外資料證(zheng)明：VC值(zhi)的(de)(de)大小(xiao)與壓實度(du)(du)及強度(du)(du)有密切(qie)關(guan)系。VC值(zhi)損失在(zai)1～2h內(nei)(nei)影響不大，大于2h后VC值(zhi)損失成(cheng)倍增長。通過氣溫(wen)在(zai)29℃時，對倉(cang)(cang)面(mian)噴(pen)霧(wu)和未(wei)噴(pen)霧(wu)兩種工況(kuang)下VC值(zhi)觀測結果（見表1）可知，做好(hao)倉(cang)(cang)面(mian)噴(pen)霧(wu)降溫(wen)工作，減小(xiao)VC值(zhi)損失，必須引起高度(du)(du)重(zhong)視。

雨天施工

在降(jiang)雨(yu)(yu)強度(du)小于3mm/h的條件下，可覆(fu)蓋防雨(yu)(yu)布繼續(xu)施工，當降(jiang)雨(yu)(yu)強度(du)達(da)到或超過(guo)3mm/h時，應停止拌和，迅速(su)完成尚未進行(xing)的卸料、平倉和碾(nian)壓作業，并采取防雨(yu)(yu)和排(pai)水措(cuo)施。當雨(yu)(yu)停時，適當調大VC值，這樣有(you)利于提(ti)高碾(nian)壓層(ceng)面結合質(zhi)量。