簡介
烏(wu)江渡水(shui)(shui)電(dian)(dian)(dian)(dian)站(zhan)(Wujiangdu Hydropower Station) 是對烏(wu)江流域實施(shi)梯級開(kai)發興建(jian)的(de)第一(yi)(yi)座(zuo)大型水(shui)(shui)電(dian)(dian)(dian)(dian)站(zhan),位于(yu)烏(wu)江中(zhong)游遵義縣烏(wu)江鎮(zhen),南(nan)距貴陽105公里(li),北離遵義55公里(li)。工(gong)(gong)程先后由長江流域規劃辦公室(shi)、中(zhong)南(nan)勘測設計院設計,集團公司水(shui)(shui)電(dian)(dian)(dian)(dian)八局負責施(shi)工(gong)(gong)。1970年(nian)開(kai)始施(shi)工(gong)(gong)準備,中(zhong)間(jian)因(yin)補做地質工(gong)(gong)作停工(gong)(gong)二(er)年(nian),1974年(nian)開(kai)始澆筑大壩混(hun)凝土,1979年(nian)第一(yi)(yi)臺機(ji)組發電(dian)(dian)(dian)(dian),1983年(nian)竣(jun)工(gong)(gong)。該電(dian)(dian)(dian)(dian)站(zhan)向貴州、四川送電(dian)(dian)(dian)(dian),支援(yuan)兩省工(gong)(gong)農業建(jian)設,是西南(nan)電(dian)(dian)(dian)(dian)網的(de)骨干電(dian)(dian)(dian)(dian)站(zhan)之(zhi)一(yi)(yi)。該電(dian)(dian)(dian)(dian)站(zhan)共(gong)裝有3臺水(shui)(shui)輪發電(dian)(dian)(dian)(dian)機(ji)組,其(qi)中(zhong)一(yi)(yi)號、二(er)號機(ji)組已分別于(yu)1979年(nian)、1981年(nian)發電(dian)(dian)(dian)(dian);三號機(ji)組安裝調試完成后,于(yu)1982年(nian)12月4日投產(chan)發電(dian)(dian)(dian)(dian),比原(yuan)計劃提前27天(tian)。電(dian)(dian)(dian)(dian)站(zhan)總裝機(ji)63萬千(qian)瓦,多(duo)年(nian)平(ping)均發電(dian)(dian)(dian)(dian)量31.05億(yi)千(qian)瓦小時,是中(zhong)國在(zai)大陸(lu)巖溶地區修(xiu)建(jian)的(de)第一(yi)(yi)座(zuo)大型水(shui)(shui)電(dian)(dian)(dian)(dian)工(gong)(gong)程。
修建背景
烏(wu)(wu)江是云(yun)貴(gui)高(gao)原上(shang)(shang)的(de)(de)一(yi)條大(da)河(he)(he),長(chang)江的(de)(de)主要(yao)支流(liu)之(zhi)一(yi)。它發源于云(yun)、貴(gui)兩省交(jiao)界(jie)線上(shang)(shang)的(de)(de)烏(wu)(wu)蒙山東麓(lu)。源頭河(he)(he)段叫做三(san)岔河(he)(he)。在貴(gui)陽(yang)之(zhi)西(xi)北與六(liu)沖河(he)(he)匯合(he)成(cheng)(cheng)烏(wu)(wu)江上(shang)(shang)游干流(liu)。烏(wu)(wu)江干流(liu)大(da)體(ti)上(shang)(shang)沿近東西(xi)向經(jing)烏(wu)(wu)江渡(du)穿越川黔線。經(jing)思南北上(shang)(shang),再(zai)經(jing)龔灘轉向西(xi)北,于四川涪陵(ling)注入(ru)長(chang)江。分別在川黔線以西(xi)、以東的(de)(de)貓(mao)跳河(he)(he)和(he)清水(shui)(shui)(shui)江,是烏(wu)(wu)江中(zhong)上(shang)(shang)游南側(右岸)的(de)(de)兩條主要(yao)支流(liu)。烏(wu)(wu)江中(zhong)游穿行在大(da)婁山以東的(de)(de)崇山峻嶺之(zhi)間(jian)。由于河(he)(he)水(shui)(shui)(shui)侵蝕和(he)地(di)下(xia)水(shui)(shui)(shui)溶蝕,往往形(xing)成(cheng)(cheng)兩、三(san)百米深(shen)的(de)(de)峽谷(gu)。烏(wu)(wu)江干支流(liu)水(shui)(shui)(shui)急(ji)灘多,水(shui)(shui)(shui)能資源豐富。
烏江(jiang)渡位于(yu)川(chuan)黔線上、烏江(jiang)南(右)岸,是(shi)(shi)貴(gui)州(zhou)省(sheng)遵(zun)義(yi)(yi)(yi)市(shi)(shi)遵(zun)義(yi)(yi)(yi)縣(xian)(xian)的(de)一(yi)個城鎮(zhen)。其北面是(shi)(shi)遵(zun)義(yi)(yi)(yi)市(shi)(shi)(較(jiao)近),南面是(shi)(shi)貴(gui)陽(yang)市(shi)(shi)(較(jiao)遠),西面是(shi)(shi)畢(bi)節縣(xian)(xian),東面是(shi)(shi)玉屏(ping)縣(xian)(xian)。
烏(wu)江(jiang)渡水電站位于烏(wu)江(jiang)渡以西附近,烏(wu)江(jiang)中上游峽(xia)谷河段。這是(shi)世(shi)界上巖(yan)溶地貌(mao)發育(yu)最典(dian)型的(de)地區之一(yi)。
烏江渡水(shui)電站設計與(yu)施工(gong)質(zhi)量優良。自1979年蓄水(shui)發(fa)電以來(lai),壩基滲漏微小,揚壓力遠低于設計值,各泄洪建筑物以及電站機(ji)組設備運行情況(kuang)良好。被(bei)評(ping)為全(quan)國優秀工(gong)程之一。
烏(wu)江渡水電(dian)站(zhan)工(gong)(gong)程(cheng)質量優(you)良。主體工(gong)(gong)程(cheng)混凝土全部(bu)合(he)格,優(you)良率(lv)達85%。帷(wei)幕灌漿、金屬結(jie)構(gou)、機組安裝及各類泄洪建(jian)(jian)筑物全部(bu)達到設(she)(she)計要求(qiu)。革新成果791項。其中有9項達到國內先進水平(ping),成功(gong)地(di)(di)解決了巖溶地(di)(di)區(qu)建(jian)(jian)設(she)(she)水電(dian)站(zhan)的水庫(ku)防(fang)滲(shen)、大壩(ba)基礎穩定、泄洪及施工(gong)(gong)后(hou)期導流(liu)等重(zhong)大技術難題,為我(wo)國今后(hou)在(zai)西南巖溶地(di)(di)區(qu)建(jian)(jian)設(she)(she)大型水電(dian)站(zhan)積累了有益(yi)的經驗(yan)。烏(wu)江渡水電(dian)站(zhan)自開工(gong)(gong)以來,精打細算,共(gong)節約資金8000多萬(wan)元,木材1萬(wan)多立方(fang)米,水泥11萬(wan)多噸。整個工(gong)(gong)程(cheng)造(zao)價沒有超過工(gong)(gong)程(cheng)概算,是我(wo)國近年來大型水電(dian)站(zhan)建(jian)(jian)設(she)(she)經濟效益(yi)最好(hao)的一(yi)個工(gong)(gong)程(cheng)。
發電能力
烏江渡(du)水(shui)電(dian)(dian)(dian)站(zhan)(zhan)共裝(zhuang)有三臺高水(shui)頭大型(xing)水(shui)輪發電(dian)(dian)(dian)機組(zu)。單機容(rong)(rong)量(liang)21萬(wan)千瓦(wa),總(zong)裝(zhuang)機容(rong)(rong)量(liang)為63萬(wan)千瓦(wa),年發電(dian)(dian)(dian)量(liang)33.4億(yi)度。它的總(zong)裝(zhuang)機容(rong)(rong)量(liang)約占貴(gui)州省水(shui)火(huo)電(dian)(dian)(dian)總(zong)裝(zhuang)機容(rong)(rong)量(liang)的40%。該電(dian)(dian)(dian)站(zhan)(zhan)全部建成投(tou)產,使貴(gui)州省的發電(dian)(dian)(dian)能力(li)增加了2/5左右,在(zai)貴(gui)州電(dian)(dian)(dian)網中發揮著骨干作用。不僅如此(ci),該電(dian)(dian)(dian)站(zhan)(zhan)的電(dian)(dian)(dian)力(li)還(huan)并入西南聯網運(yun)行,除(chu)滿(man)足(zu)貴(gui)州省的用電(dian)(dian)(dian)需要外,還(huan)將多余的電(dian)(dian)(dian)輸往四(si)川,主要補充重(zhong)慶地(di)區電(dian)(dian)(dian)力(li)之不足(zu)。
主要結構
烏(wu)江(jiang)渡水電(dian)站控制流(liu)域(yu)面積:27790平(ping)方公(gong)里。
多年(nian)平均流量:502立方米/秒(miao)。
設計(ji)洪水流量(liang):19200立方米/秒。
校核洪水位:762.8米。
正常高水位:760米(mi)。
死水位:720米。
校核(he)尾水位:672.9米,
設(she)計尾水位(wei):668.3米。
最(zui)低尾水位:625.72米。
總(zong)庫(ku)容:23億立方米。
主壩壩型:混(hun)凝土拱形重(zhong)力壩。
壩頂高程(cheng):765米。
最大壩高:165米(為當(dang)時(shi)我國已建成水電站的第一高壩)。
壩(ba)頂弧長:368米。
壩體工程量:193萬立方米。
主要(yao)泄洪方式:壩(ba)頂溢流(liu)、隧洞泄洪。
壩體在700米高程(cheng)以下為整(zheng)體結構(gou),橫縫灌(guan)漿;700米高成以上(shang)為懸(xuan)臂梁結構(gou),橫縫不灌(guan)漿。壩型結構(gou)特點是:由于拱軸(zhou)曲率很小(xiao),因而在兩岸(an)拱座范圍內,軸(zhou)向(xiang)力(H)較小(xiao),順(shun)河流方向(xiang)(近東(dong)西向(xiang))拱端剪力(V)較大。
主壩(ba)中部(bu)為溢(yi)流(liu)(liu)壩(ba),設有(you)4個(ge)溢(yi)流(liu)(liu)表孔(kong)。溢(yi)流(liu)(liu)孔(kong)設有(you)弧形閘(zha)門(men)(13×19 ),并設有(you)檢修閘(zha)門(men)井和(he)工(gong)作閘(zha)門(men)井。溢(yi)流(liu)(liu)面(板(ban))末端挑流(liu)(liu)鼻坎高程669.367米。溢(yi)流(liu)(liu)壩(ba)頂設有(you)行車和(he)閘(zha)門(men)啟閉(bi)設備。
溢流壩北、南(nan)兩(liang)側設(she)有左(zuo)、右(you)(you)溢洪(hong)道。兩(liang)岸分別(bie)設(she)有左(zuo)、右(you)(you)岸泄(xie)洪(hong)洞。在壩體內,左(zuo)、右(you)(you)泄(xie)洪(hong)洞高程(cheng)720米。左(zuo)、右(you)(you)泄(xie)洪(hong)道內側左(zuo)、右(you)(you)泄(xie)洪(hong)中孔高程(cheng)680米。導流底孔高程(cheng)628.7米。
電站主廠(chang)房為壩后式廠(chang)房。付廠(chang)房在(zai)主廠(chang)房上游(you)側的壩內。主廠(chang)房與壩體(ti)之(zhi)間設有廠(chang)壩分(fen)縫。壩體(ti)下游(you)面22萬伏開關站基面高程(cheng)686米。引水(shui)鋼管埋設在(zai)壩體(ti)內,進水(shui)口高程(cheng)700米。水(shui)輪機的安裝高程(cheng)622.5米。
壩體下游面人行道高程724.2米。
壩頂左側設(she)置有升船機。壩體上還安裝有攔污柵等設(she)備。
上游圍(wei)堰右(you)岸(an)設有導流(liu)隧洞(dong)。在(zai)平面上它位于右(you)岸(an)泄洪洞(dong)外側(ce)(靠河(he)道一側(ce))。右(you)岸(an)泄洪洞(dong)內(nei)側(ce)(靠山(shan)里(li)一側(ce))設有放(fang)空洞(dong)。在(zai)立面上,放(fang)空洞(dong)在(zai)右(you)岸(an)泄洪洞(dong)和導流(liu)洞(dong)之間(高程在(zai)680米(mi)和700米(mi)之間)。
左(zuo)岸有上壩(ba)隧洞(dong)(dong)。右岸有進(jin)廠交(jiao)通洞(dong)(dong)。
壩(ba)基進(jin)行了固結(jie)灌漿。在壩(ba)基上游(you)側(ce)和廠基下(xia)游(you)側(ce)分別設置(zhi)了防滲帷(wei)幕。
壩(ba)軸線位(wei)于壩(ba)基上游帷幕前面。
地質特征
烏江(jiang)渡(du)水(shui)電(dian)站(zhan)壩址(zhi)河(he)(he)段兩岸(an)山(shan)高(gao)(gao)300余米。河(he)(he)水(shui)位625.7米。河(he)(he)面寬70米。700米高(gao)(gao)程以下谷坡坡度(du)(du)約為(wei)60°,700米高(gao)(gao)程以上谷坡坡度(du)(du)約為(wei)40°。河(he)(he)谷呈“V”型。
壩基(ji)地層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)為下(xia)三疊統玉龍山石(shi)(shi)灰(hui)巖(yan)(T1)總厚(hou)度(du)233米。按巖(yan)性可(ke)分(fen)為兩大(da)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng):第(di)一(yi)大(da)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)(T1)以深灰(hui)色(se)中厚(hou)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)和(he)(he)薄層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)石(shi)(shi)灰(hui)巖(yan)為主,夾多(duo)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)極薄的炭(tan)(tan)質(zhi)(zhi)(zhi)(zhi)頁巖(yan)和(he)(he)鈣質(zhi)(zhi)(zhi)(zhi)頁巖(yan),厚(hou)110米。依頁巖(yan)夾層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)的多(duo)少,第(di)一(yi)大(da)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)可(ke)分(fen)為三個小(xiao)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)。第(di)二(er)大(da)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)(T1)為深灰(hui)色(se)厚(hou)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)塊狀(zhuang)和(he)(he)中厚(hou)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)致(zhi)密石(shi)(shi)灰(hui)巖(yan),夾極少量炭(tan)(tan)質(zhi)(zhi)(zhi)(zhi)頁巖(yan)和(he)(he)炭(tan)(tan)質(zhi)(zhi)(zhi)(zhi)薄膜,厚(hou)123米。石(shi)(shi)灰(hui)巖(yan)堅脆質(zhi)(zhi)(zhi)(zhi)純,平均飽(bao)和(he)(he)極限抗壓強度(du)在600公斤/厘米以上。
玉龍山石灰巖以下,據壩趾50米處,為下三疊統九級灘頁巖——粘土頁巖(T1),厚55~83米。壩后式廠房距九級灘頁巖僅20米。玉龍山石灰巖之上,為下三疊統沙灣堡頁巖(T1)壩(ba)址上游(you)1公里處,地層至西向(xiang)(xiang)(xiang)東倒轉。壩(ba)址區地層走(zou)向(xiang)(xiang)(xiang)NE 5°~15°,傾(qing)向(xiang)(xiang)(xiang)NWW(上游(you)),傾(qing)角60°左(zuo)右。壩(ba)區地質構(gou)造主要受燕山期NNE向(xiang)(xiang)(xiang)構(gou)造體系控制。地層在近東西向(xiang)(xiang)(xiang)應力場作用下,強烈擠壓、倒轉,并(bing)產(chan)生多(duo)組斷裂及扭曲破裂,構(gou)造破壞嚴重。其中,右岸斷裂密集(ji),巖體完整性差。
玉龍(long)山石(shi)灰(hui)巖(yan)地下(xia)巖(yan)溶(rong)發育。巖(yan)溶(rong)形態有溶(rong)洞(dong)、暗河(he)、豎井及斜井等。兩(liang)岸已見溶(rong)洞(dong)14個,可(ke)測長(chang)度1456米,總體積達(da)86193立方米(右(you)岸77843立方米)。巖(yan)溶(rong)發育主(zhu)要規律是:
⑴、發育強度與石灰巖性狀(zhuang)和(he)夾層(ceng)巖性有(you)關。第(di)(di)(di)二大層(ceng)較(jiao)第(di)(di)(di)一(yi)大層(ceng)發育。在第(di)(di)(di)一(yi)大層(ceng)中(zhong),第(di)(di)(di)二小層(ceng)巖溶最發育,第(di)(di)(di)三(san)小層(ceng)次之,第(di)(di)(di)一(yi)小層(ceng)最弱(夾層(ceng)最多)。
⑵、發育(yu)方(fang)向(xiang)受構造控(kong)制。主要方(fang)向(xiang)為NNE向(xiang)(巖層走向(xiang))及NWW向(xiang)(張性斷(duan)裂(lie)方(fang)向(xiang))。局部(bu)受NE向(xiang)構造控(kong)制。
⑶、發育(yu)成層性明顯。右岸巖(yan)(yan)溶可分為(wei)四層,其(qi)高(gao)(gao)(gao)程分別為(wei):630~640米、660~670米、695~705米和(he)725~735米,與烏江兩岸階地高(gao)(gao)(gao)程基(ji)本相應。其(qi)余(yu)各(ge)高(gao)(gao)(gao)程巖(yan)(yan)溶以(yi)垂(chui)直巖(yan)(yan)溶為(wei)主(zhu),并與各(ge)層水平溶洞相連,形成樹枝(zhi)狀巖(yan)(yan)溶系統。在近(jin)代河(he)床以(yi)下300米的深度,亦(yi)見有沿NE向斷層垂(chui)直發育(yu)的深部巖(yan)(yan)溶。
壩基工程地質條件(jian)右(you)岸較差,左岸次之,河(he)床較好。
上述壩(ba)型結(jie)構特點決定(ding)(ding)了兩岸壩(ba)肩深部抗(kang)滑穩(wen)(wen)定(ding)(ding)條件(jian)(jian)是(shi)影響大壩(ba)安全的重要(yao)因素(su)(su)之一。分析壩(ba)肩抗(kang)滑穩(wen)(wen)定(ding)(ding)條件(jian)(jian),主要(yao)是(shi)要(yao)查明和分析700米高程以下拱(gong)形重力(li)壩(ba)的兩岸壩(ba)肩拱(gong)座基(ji)礎部位的巖體中,沿拱(gong)座方向(北西西向)和底平(ping)面(mian)有(you)無明顯(xian)而(er)連(lian)續(xu)的軟(ruan)弱結(jie)構面(mian)存(cun)在。這是(shi)壩(ba)肩深部抗(kang)滑穩(wen)(wen)定(ding)(ding)的關鍵因素(su)(su)或控制因素(su)(su)。
復雜的(de)(de)地質條件決定(ding)(ding)了烏江渡(du)水電站的(de)(de)主要工程地質問(wen)題(ti)是:⑴、庫(ku)、壩(ba)(ba)(ba)(ba)區(qu)滲(shen)漏;⑵、壩(ba)(ba)(ba)(ba)基(ji)和(he)壩(ba)(ba)(ba)(ba)肩(jian)(jian),主要是右岸壩(ba)(ba)(ba)(ba)肩(jian)(jian)的(de)(de)深(shen)部抗滑穩定(ding)(ding)問(wen)題(ti)。為了防滲(shen)和(he)提高壩(ba)(ba)(ba)(ba)基(ji)、壩(ba)(ba)(ba)(ba)肩(jian)(jian)巖體(ti)的(de)(de)整體(ti)性和(he)穩定(ding)(ding)性,對(dui)壩(ba)(ba)(ba)(ba)基(ji)進行(xing)了固(gu)結灌漿;設置了防滲(shen)帷幕,并與兩岸上游相對(dui)隔水層相連接;對(dui)右壩(ba)(ba)(ba)(ba)肩(jian)(jian)的(de)(de)軟弱結構(gou)面進行(xing)了專門(men)的(de)(de)處(chu)理,同(tong)時采(cai)取了改選壩(ba)(ba)(ba)(ba)型(xing)等措施。
修建原理
烏江渡水電站壩(ba)(ba)(ba)(ba)(ba)基(ji)(ji)巖(yan)體(ti)內(nei)軟弱結構面的(de)(de)(de)發育沒有明(ming)顯的(de)(de)(de)分(fen)異,不(bu)(bu)同方(fang)向(xiang)的(de)(de)(de)裂隙(xi)普遍存在(zai)(zai)。在(zai)(zai)這種情況下,深(shen)部滑(hua)動面往往是由(you)壩(ba)(ba)(ba)(ba)(ba)基(ji)(ji)內(nei)最(zui)大(da)(da)剪(jian)應(ying)力帶(dai)(dai)的(de)(de)(de)分(fen)布所決定(ding)(ding)。因此,在(zai)(zai)設(she)計(ji)過程(cheng)中(zhong),需(xu)要(yao)(yao)(yao)沿最(zui)大(da)(da)剪(jian)應(ying)力帶(dai)(dai),并根據(ju)這個帶(dai)(dai)的(de)(de)(de)綜合工程(cheng)地質性(xing)(xing)(xing)質指(zhi)標,校核(he)壩(ba)(ba)(ba)(ba)(ba)基(ji)(ji)的(de)(de)(de)深(shen)部抗滑(hua)穩(wen)定(ding)(ding)性(xing)(xing)(xing)。據(ju)試驗和有限單元法計(ji)算,由(you)于(yu)距河(he)床壩(ba)(ba)(ba)(ba)(ba)段很近的(de)(de)(de)下游九級(ji)灘頁(ye)巖(yan)強度(du)低,變形大(da)(da),因而應(ying)力在(zai)(zai)玉(yu)龍山石灰巖(yan)內(nei)高度(du)集中(zhong),其剪(jian)應(ying)力最(zui)高帶(dai)(dai)與(yu)(yu)壩(ba)(ba)(ba)(ba)(ba)底面約成20°~25°的(de)(de)(de)交角(jiao)。實(shi)(shi)際上,壩(ba)(ba)(ba)(ba)(ba)基(ji)(ji)內(nei)也確實(shi)(shi)有一組裂隙(xi)沿這一方(fang)向(xiang)發育。因此,根據(ju)這個帶(dai)(dai)的(de)(de)(de)加權平均(包括裂隙(xi)與(yu)(yu)完整巖(yan)石)抗剪(jian)強度(du)指(zhi)標,校核(he)了壩(ba)(ba)(ba)(ba)(ba)基(ji)(ji)巖(yan)體(ti)深(shen)部抗滑(hua)穩(wen)定(ding)(ding)性(xing)(xing)(xing)。結果發現,按原來設(she)計(ji)的(de)(de)(de)壩(ba)(ba)(ba)(ba)(ba)型,壩(ba)(ba)(ba)(ba)(ba)基(ji)(ji)巖(yan)體(ti)深(shen)部抗滑(hua)穩(wen)定(ding)(ding)性(xing)(xing)(xing)不(bu)(bu)能滿足(zu)要(yao)(yao)(yao)求。于(yu)是,將原設(she)計(ji)的(de)(de)(de)一般類型的(de)(de)(de)重(zhong)力壩(ba)(ba)(ba)(ba)(ba)改為拱(gong)(gong)形重(zhong)力壩(ba)(ba)(ba)(ba)(ba),把(ba)20%~30%的(de)(de)(de)水平推力傳到兩岸壩(ba)(ba)(ba)(ba)(ba)肩(jian)(jian)上,以(yi)保(bao)證大(da)(da)壩(ba)(ba)(ba)(ba)(ba)有足(zu)夠的(de)(de)(de)抗滑(hua)穩(wen)定(ding)(ding)性(xing)(xing)(xing)。這樣一來,對(dui)于(yu)選定(ding)(ding)的(de)(de)(de)拱(gong)(gong)形重(zhong)力壩(ba)(ba)(ba)(ba)(ba),河(he)床壩(ba)(ba)(ba)(ba)(ba)基(ji)(ji)和左壩(ba)(ba)(ba)(ba)(ba)肩(jian)(jian)的(de)(de)(de)深(shen)部抗滑(hua)穩(wen)定(ding)(ding)安(an)全系數分(fen)別達到4.67和4.69,均能滿足(zu)穩(wen)定(ding)(ding)性(xing)(xing)(xing)要(yao)(yao)(yao)求。雖然(ran)(ran)右壩(ba)(ba)(ba)(ba)(ba)肩(jian)(jian)在(zai)(zai)天(tian)然(ran)(ran)狀態下穩(wen)定(ding)(ding)性(xing)(xing)(xing)較(jiao)差,但(dan)是對(dui)右壩(ba)(ba)(ba)(ba)(ba)肩(jian)(jian)主(zhu)要(yao)(yao)(yao)軟弱結構面進(jin)行專(zhuan)門處理后,亦能滿足(zu)拱(gong)(gong)形重(zhong)力壩(ba)(ba)(ba)(ba)(ba)的(de)(de)(de)穩(wen)定(ding)(ding)性(xing)(xing)(xing)要(yao)(yao)(yao)求。
施工特點
施工(gong)(gong)(gong)方面,成(cheng)功(gong)地采用(yong)人工(gong)(gong)(gong)砂石料,建成(cheng)了(le)(le)年(nian)產(chan)200萬噸的砂石加工(gong)(gong)(gong)系統(tong),多(duo)(duo)年(nian)平均(jun)生產(chan)成(cheng)本為(wei)9.13元(yuan)/米(mi)(mi)3;采用(yong)高壓(ya)水泥灌(guan)(guan)漿(jiang)帷幕,成(cheng)功(gong)地解(jie)決了(le)(le)水庫滲漏(lou)問題(ti),帷幕總長約1000米(mi)(mi),帷幕灌(guan)(guan)漿(jiang)鉆孔總深度達19萬米(mi)(mi);試制成(cheng)功(gong)壓(ya)力(li)為(wei)100公(gong)斤(jin)/厘(li)米(mi)(mi)2的高壓(ya)灌(guan)(guan)漿(jiang)機(ji),實際使(shi)用(yong)最(zui)大(da)灌(guan)(guan)漿(jiang)壓(ya)力(li)60公(gong)斤(jin)/厘(li)米(mi)(mi)2;采用(yong)大(da)型鋼木(mu)模(mo)板及混凝(ning)土預(yu)制壩面、廊道(dao)模(mo)板;在混凝(ning)土中使(shi)用(yong)不(bu)同性能的外加劑,單(dan)位體積(ji)混凝(ning)土平均(jun)水泥耗(hao)量為(wei)195公(gong)斤(jin);在施工(gong)(gong)(gong)工(gong)(gong)(gong)藝不(bu)斷革(ge)新(xin)的基礎上,各主要施工(gong)(gong)(gong)工(gong)(gong)(gong)序(xu)實現了(le)(le)綜合機(ji)械化,多(duo)(duo)年(nian)平均(jun)全(quan)員勞動生產(chan)率為(wei)4028元(yuan),節約了(le)(le)大(da)量建設投資。
歷史沿革
烏江(jiang)渡水(shui)電(dian)(dian)(dian)站(zhan)是我國20世紀(ji)80年(nian)(nian)代初(chu)在(zai)貴州(zhou)(zhou)喀(ka)斯(si)特(te)地貌上興(xing)建(jian)(jian)(jian)的(de)(de)(de)第一個大(da)型水(shui)電(dian)(dian)(dian)站(zhan),是我國烏江(jiang)梯級電(dian)(dian)(dian)站(zhan)開發(fa)(fa)10座(zuo)(zuo)大(da)中(zhong)型電(dian)(dian)(dian)站(zhan)的(de)(de)(de)第一座(zuo)(zuo),總裝(zhuang)機(ji)容量為三(san)臺(tai)(tai)21萬(wan)千(qian)(qian)瓦(wa)機(ji)組;電(dian)(dian)(dian)站(zhan)大(da)壩(ba)高(gao)165米,是當時我國在(zai)喀(ka)斯(si)特(te)地貌上興(xing)建(jian)(jian)(jian)的(de)(de)(de)第一座(zuo)(zuo)高(gao)壩(ba)。20年(nian)(nian)來,這(zhe)座(zuo)(zuo)水(shui)電(dian)(dian)(dian)站(zhan)已累計發(fa)(fa)電(dian)(dian)(dian)500多億度電(dian)(dian)(dian),為貴州(zhou)(zhou)的(de)(de)(de)經濟建(jian)(jian)(jian)設(she)做出的(de)(de)(de)巨大(da)貢獻。貴州(zhou)(zhou)“西電(dian)(dian)(dian)東送(song)”首批(pi)開工(gong)項(xiang)目(mu)——烏江(jiang)渡水(shui)電(dian)(dian)(dian)站(zhan)擴(kuo)機(ji)增容工(gong)程(cheng),正在(zai)這(zhe)里(li)進行緊張的(de)(de)(de)建(jian)(jian)(jian)設(she),首臺(tai)(tai)擴(kuo)機(ji)機(ji)組將于2012年(nian)(nian)8月15日(ri)試投(tou)產發(fa)(fa)電(dian)(dian)(dian)。這(zhe)座(zuo)(zuo)電(dian)(dian)(dian)站(zhan)擴(kuo)機(ji)增容項(xiang)目(mu)完工(gong)后(hou),將新增加2兩臺(tai)(tai)25萬(wan)千(qian)(qian)瓦(wa)機(ji)組,原(yuan)三(san)臺(tai)(tai)21萬(wan)千(qian)(qian)瓦(wa)機(ji)組將增容12萬(wan)千(qian)(qian)瓦(wa),總裝(zhuang)機(ji)容量將達125萬(wan)千(qian)(qian)瓦(wa)。這(zhe)座(zuo)(zuo)有20年(nian)(nian)歷史的(de)(de)(de)水(shui)電(dian)(dian)(dian)大(da)壩(ba)將在(zai)我國“西電(dian)(dian)(dian)東送(song)”建(jian)(jian)(jian)設(she)中(zhong)煥發(fa)(fa)青春。
該(gai)水(shui)電(dian)站(zhan)位于巖溶(rong)(rong)地區(qu),防(fang)止壩(ba)(ba)基(ji)(ji)和(he)兩(liang)岸(an)滲(shen)漏(lou)是關鍵問題。自(zi)1958年起對(dui) 壩(ba)(ba)址(zhi)的(de)工(gong)程地質和(he)水(shui)文地質條(tiao)(tiao)件進行(xing)勘探,完成(cheng)(cheng)了(le)(le)大量(liang)的(de)勘探試驗工(gong)作(zuo)。采(cai)用高(gao)壓(ya)(ya)水(shui)泥(ni)灌漿(jiang)帷幕(mu)(mu)(mu)與(yu)上(shang)游(you)(you)砂頁巖隔水(shui)層相聯接的(de)防(fang)滲(shen)措施。帷幕(mu)(mu)(mu)線路布置,在(zai)壩(ba)(ba)體范(fan)圍內與(yu)壩(ba)(ba)軸線平(ping)行(xing),自(zi)建基(ji)(ji)面(mian)垂直(zhi)向(xiang)下在(zai)玉龍山灰巖中(zhong)形成(cheng)(cheng)幕(mu)(mu)(mu)體。左(zuo)、右兩(liang)岸(an)因被兩(liang)條(tiao)(tiao)大斷層將 頁巖錯斷,形成(cheng)(cheng)滲(shen)漏(lou)通道,因此,兩(liang)岸(an)防(fang)滲(shen)帷幕(mu)(mu)(mu)線路均自(zi)壩(ba)(ba)肩(jian)折向(xiang)上(shang)游(you)(you),并(bing)向(xiang)山體內延伸。壩(ba)(ba)基(ji)(ji)帷幕(mu)(mu)(mu)總長(chang)(chang)1020m,帷幕(mu)(mu)(mu)線底部最深處達河床以(yi)下200m,帷幕(mu)(mu)(mu)總面(mian)積18.9萬m2,灌漿(jiang)鉆孔總長(chang)(chang)約19萬m。采(cai)用不沖洗(xi)高(gao)壓(ya)(ya)水(shui)泥(ni)灌漿(jiang),最大灌漿(jiang)壓(ya)(ya)力6MPa,壓(ya)(ya)力下限不低于2MPa。在(zai)左(zuo)岸(an)壩(ba)(ba)肩(jian)巖基(ji)(ji)內高(gao)程640~670m緊(jin)靠大壩(ba)(ba)建基(ji)(ji)面(mian)設(she)置了(le)(le)長(chang)(chang)93m的(de)混凝土防(fang)滲(shen)墻。在(zai)廠(chang)房下游(you)(you)邊線和(he)廠(chang)房兩(liang)側設(she)置有全長(chang)(chang)242m的(de)水(shui)泥(ni)灌漿(jiang)帷幕(mu)(mu)(mu)。河床以(yi)上(shang)較(jiao)大溶(rong)(rong)洞清(qing)理后,回(hui)填混凝土。深部溶(rong)(rong)洞用高(gao)壓(ya)(ya)灌漿(jiang)處理。壩(ba)(ba)基(ji)(ji)和(he)兩(liang)岸(an)處理后,在(zai)120m工(gong)作(zuo)水(shui)頭下,每24h滲(shen)漏(lou)量(liang)20m3。實際(ji)揚壓(ya)(ya)力遠小于設(she)計值(zhi)。
為了更大程度滿足系統的(de)(de)調(diao)峰、調(diao)頻和事(shi)故備用需要(yao),2003年12月完成了擴(kuo)大裝(zhuang)機容量(liang)的(de)(de)施工(gong)。擴(kuo)大裝(zhuang)機容量(liang)2×25萬kW,擴(kuo)機后水(shui)庫死水(shui)位736m。擴(kuo)機工(gong)程電站廠(chang)房(fang)采用地(di)(di)下(xia)式(shi)廠(chang)房(fang)布(bu)(bu)置(zhi)方案(an),引水(shui)發電系統布(bu)(bu)置(zhi)在(zai)壩(ba)下(xia)左(zuo)岸山體內。擴(kuo)機工(gong)程主(zhu)要(yao)建(jian)筑物(wu)(wu)包括(kuo)岸邊(bian)壩(ba)式(shi)進水(shui)口(kou)、引水(shui)隧洞、尾水(shui)洞、尾水(shui)出口(kou)主(zhu)廠(chang)房(fang)(長×寬×高:84.2× 23.9× 55.3m)、主(zhu)變洞開關(guan)站、出線平(ping)臺、進廠(chang)交通洞、地(di)(di)下(xia)廠(chang)房(fang)防(fang)滲排(pai)水(shui)設(she)施等。除進水(shui)口(kou)的(de)(de)部分建(jian)筑物(wu)(wu)及(ji)尾水(shui)出口(kou)、出線平(ping)臺地(di)(di)面副(fu)廠(chang)房(fang)以外,其(qi)它均布(bu)(bu)置(zhi)于地(di)(di)下(xia)。工(gong)程土石(shi)方明(ming)挖量(liang)35.35萬m,石(shi)方洞挖36.4萬m,混凝土總(zong)量(liang)13.34萬m。擴(kuo)機工(gong)程概(gai)算總(zong)投資(zi)為8.33億(yi)元。