水庫淤積形成及其影響和應(yīng)對(duì)措施

1、水庫淤積形成及其影響和應(yīng)對(duì)措施Reservoir formation and its influenceand Countermeasures在天然河流上建筑水庫后，將會(huì)給該區(qū)域一系列的影響。庫區(qū)水 位的舉高，使過水?dāng)嗝鏀U(kuò)展，水力坡降變緩，水流速度減小。這些將 致使水流挾沙才能的降低，然后改動(dòng)原河道的泥沙運(yùn)動(dòng)規(guī)則，致使很 多泥沙在庫區(qū)逐步沉積淤積。也就是說，建筑水庫成為河流泥沙淤積 的主要原因。In the natural river after building reservoir, will give the area a series of. Reservoir water level

2、up, make the cross section, hydraulic gradient is slow, flow velocity decreases. These will lead to reduced flow, sediment movement rules and then change the original river, causing a lot of sediment deposition in the reservoir sedimentation gradually. That is to say, building reservoir become the m

3、ain cause of river sediment.在我國(guó)華北的黃河和海河水系，水流含沙量很大，庫區(qū)的淤積也 就相對(duì)較高。例如黃河三門峽水庫，多年均勻含沙量達(dá)37.8kg/m?， 在1960-1970年，水庫總淤積泥沙達(dá)55.5億t，使庫區(qū)的庫容丟失 高達(dá)43%。In North China s the Yellow River and Haihe River, sediment concentration, reservoir sedimentation is relatively high. For example, the Yellow River Sanmenxia reservo

4、ir, years of uniform sediment concentration up to 37.8 kg/m?, in 1960-1970, total reservoir silting mud Sardar 5550000000 T, the reservoir capacity loss of up to 43%.水庫泥沙淤積的對(duì)水庫運(yùn)用和上下流河流發(fā)生的不良影響是多 方面的。淤積使水庫的調(diào)理庫容削減，降低水庫的調(diào)理才能以及綜合 利用效益。壩前淤積，很多泥沙隨水流進(jìn)入庫區(qū)，就會(huì)加大對(duì)過水建 筑物和水輪機(jī)的磨損，降低設(shè)備安全和建筑物的使用壽命。并且，當(dāng) 河流的淤積向水庫推動(dòng)時(shí)，也

5、會(huì)向上游延伸，即所謂的“驕傲自滿” 表象。這會(huì)添加庫區(qū)的吞沒面積，不只帶來很多丟失，甚至有能夠形 成社會(huì)動(dòng)搖。此外，水庫向下流泄放清水，使得下流的水流挾沙力增 大，然后致使下流河段的沖刷，導(dǎo)致水位降低，河道變形。The reservoir sedimentation of the reservoir and downstream river adverse influence in many aspects. The reservoir sedimentation conditioning capacity cuts, reduce reservoir conditioning ability

6、 and comprehensive utilization benefit. Sedimentation in front of the dam, a lot of silt into the reservoir with the water, will increase the wear of water turbine building and the service life of equipment, reduce the security and the building. And, when the reservoir sedimentation River to promote

7、, will be extended to the upstream, the so-called be big with pride representation.This will add the reservoir area not only engulfed, bring a lot of loss, even to form social stability. In addition, the downward flow of water, making obscene sediment-carrying capacity increases, then the dirty rive

8、r erosion, lowering the water level, river deformation.根據(jù)黃耀華，黃煜齡對(duì)天然河道長(zhǎng)河段一維非安穩(wěn)流的數(shù)模研討 可知，泥沙運(yùn)動(dòng)的規(guī)則類似于水體，不只遵守接連條件，并且也遵守 運(yùn)動(dòng)方程的需求.三峽大學(xué)彭輝教授聯(lián)系他們的主意，并根據(jù)非均勻 質(zhì)不平衡輸沙原理樹立水庫泥沙淤積的一維數(shù)學(xué)模型，核算中，按全 沙形式和區(qū)分時(shí)段、河段，逐時(shí)段、逐河段進(jìn)行。According to Huang Yaohua, the number of die research Huang Yuling on natural long reaches of rivers,

9、 the one dimensional non steady flow, sediment movement rules are similar to water, not only to comply with the successive conditions, and also comply with the equations of motion. Professor Peng Hui of China Three Gorges University to contact their idea, and according to the heterogeneity of non-eq

10、uilibrium sediment transport theory to establish a one-dimensional mathematical model, sediment reservoir siltation calculation, according to the whole sand forms and between sessions, river, river, a time.一維水流泥沙沖淤方程組應(yīng)滿意以下方程式中，H為水位；Q為 流量;，r為水能坡降；口為流速；A為過水面積；g為重力加速度；S為水中含沙量；Y為泥沙干重度；a為沖淤面積；K為系數(shù)；a為 系數(shù)；

11、m為指數(shù)；B為河寬；t為時(shí)刻；S*為水流挾沙力；3為泥沙 靜水沉速；P為懸沙級(jí)配；CL為核算河段總長(zhǎng)；X為斷面等距離，一 般來說 L=CL/X=8。Flow and sediment siltation should be satisfied with the one-dimensional equations following equation, H level; Q, R flow; water gradient; export velocity; A water area; g for the acceleration of gravity; S of sediment concent

12、ration in water; gamma for sediment dry density; a for scouring and silting area; K coefficient;a coefficient; m index; B for river width; t moment; S* sediment-carrying capacity; W is the sediment settling velocity of suspended sediment grading; P; CL X as chief accounting section; section distance

13、, generally L=CL/X=8.將上述方程進(jìn)行理想化處置，做出如下假定：將整個(gè)時(shí)段區(qū)分紅 若干小時(shí)段，假定每個(gè)時(shí)段除沖淤面積外其他要素均不改動(dòng)；將河段 區(qū)分紅若干小河段，假定每個(gè)小河段內(nèi)流量不變；疏忽項(xiàng)的影響，不 思考流速改變，假定淤積泥沙在水庫中均勻平鋪。則經(jīng)過上述方程即 可求得水庫的淤積量與時(shí)刻的函數(shù)聯(lián)系。因而，當(dāng)求得的水庫淤積量 抵達(dá)或許挨近水庫的死庫容時(shí)，就要進(jìn)行采納清淤辦法。The above equations are ideal disposal, make the following assumptions: the time zone into several small time, assuming that each time except the scouring and silting area outside the other factors are not changed; the river area into several small sections, each section of river flow rate unchanged; negligence of items, do not think about the flow rate changes, if sediment even in the reservoir