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1、江恩惠:河道治理工程效用及其剖析Comprehensive effective analysis of the programs and measures of river regulation on different riversJIANG En-Hui LIUYan LI Jun-Hua ZHAO Lian-Jun(Yellow River Institute of Hydraulic Research , Zhengzhou 450003 China)Abstract: owing to the different river birthplace of the world, drai

2、nage area surface and the different conditions which are underlying surface of river erosion, its characteristics of river regulation and measures are obvious different. When various countries and regions launch different regulations and exploitations in view of the characteristics of the river, it

3、have taken the necessary regulating program for the certain purpose, and also appear various dam projects, its regulating measures, programs. and the dam forms adapt greatly the characteristics of river, which is a matter of concern. Therefore, in this context, in allusion to some typical river whic

4、h at home and abroad regulating programs and measures to analyze, it broadly summed up 8 typical regulating programs, and it corresponds to the river training situation to give a presentation, then put forward the auxiliary relations between the aim of regulation and training programs, measures. Key

5、 words: the aim of regulation, training programs ,measures1 Different regulating purpose of river regulating measure and program As we all know, owing to the result of the interaction between current and riverbed, the natural channel morphology are almost straight, most of which are bend, then a pla

6、ne is one after another reverse curve. river regulation is often conform to the development 0f channel processes , follow the basic law of fluvial process and adopt homolothegous regulating measures and the disposal pattern of engineering.Because the differentness of regulation purpose, different ri

7、ver channel regulation often suited to the characteristics of the rivers regulation program, regulating measures which are adopted and correspond engineering form is also all around it is regulation program to launch According to the analysis of the typical river which is at home and abroad, the dif

8、ferent channel regulation purposes of the regulation measures comprehensive analysis as follows: 1.1 Single shore regulating measures of the sandy river with the purpose of controlling engineering to control fluvial process and insuring flood control safety.1.1.1 The purpose and measure of the singl

9、e shore sandy river regulating measures.The typical river actualizing single shore sandy river regulating measures has Yellow River and Liaohe river, water sediment and riverway characteristics of these two rivers have a total of three characteristics: (1)floods violent ups and downs. (2) Sandy (all

10、uvial) river, the river has changed loitering; (3) arduous flood task. so the regulating purpose is basic same ,it is to improve the river shape of the cross-sectional and the plane, control mainstream, stable fluvial process, under the premise of ensuring the safety of flood control, in favor of ir

11、rigation and peoples production and life flood in the shoal area and flooded area .Training measure with based regulating engineering and the supplement of bend cut off and dredging.The river training project of the Yellow River downstream is slightly curved regulation .In the training program singl

12、e bank control is adopted. Guiding slipped to bend, we make construction project only in the curve bank. Making the dam to protect the bend, making the bend to leading the wandering is the dam used type of the braided river course of the Yellow River downstream. The micro bend river training Program

13、 is also used in the Liaohe River. For wandering river, we construct training short spur dikes in the concave bank which is danger. At the same time, meander cut-offs which is necessary is carried, which could control and guide the main river, protect the embankment, stabilize the river regime, so t

14、he river could translate to micro bend type. For wandering river, we generally arrange crony in the concave bank which often occur erosion, which could protect concave bank, greet the mainstream, and maintain the existing river regime. 1.1.2 The situation of single bank training project of the sandy

15、 river course After three decades of exploration and practice in the Yellow River micro bend-rectification program, we have make the wandering area of wandering river smaller than that under natural conditions, improved the water flow, reduced the main river swinging area, improved the cross-section

16、al shape, reduced across-river, ramp-river threaten, enhanced the safety of flood control, effectively prevented the collapse of water, removing the village, improved the conditions of the diversion, and improved industry and agriculture, urban water supply protection rate. But there are also some p

17、roblems: some sections of adapt poorly to the new conditions of water and sediment, river training works is imperfect, often appear adverse river regime, strength of the already constructed building works is scarcity, stability is poor.The Liaohe River downstream training projects have been complete

18、d in accordance with planning requirements which suffer the three floods in 1986, 1989 and2005, protect the safety of flood control along the riverine areas, and make remarkable economic and social benefits. For example the wandering river course form Liu He River Estuary to Hong Miao Bridge, the us

19、e of gabion short groin is better. This could fight against larger flowing water and overflow, and play a crucial role in stabilizing the river. The scope of loitering has been significantly narrowed and effective control over the mainstream, so as to stabilize the river. The problems, for example,

20、that groins suffer serious erode from returning water among groins, the flood period meet with dangerous situation. However, within recent years the obstruction has been cleaned out and the flood houses and local people have been moved in the Liaohe rivers course, the assignment of flood control in

21、beach is obscure. We generally did not rush to deal with an emergency in flood season, but regulating the works after the floods. 1.2 The training projects of more water and less sediment river which for the purpose of protecting bottomland and bank, assuring shipping to ensure safety of flood water

22、 1.2.1 The purpose and measure of the single- Sides of the less-water and more-sand river This typical representative river is the Yangtze River. The average annual flow into the sea for years is up to 960 billion m3, accounting for over one-third of the total volume of water in rivers into the sea.

23、 But the sediment is not great, and the velocity is high, the slope is large. During the flood period frequently reaches top form beachfront, which causes beach collapsed. Mainstream flows along the larger horizontal direction which leads the river course to swing largely, bring the peoples life ext

24、remely difficult, even threaten the safety of peoples lives. The purposes of punishment are to protect the riverbank, improve stream discharge capacity, protect the safety use of flood control projects, and ensure the safety of flood control. Maintaining the waterway depth is conducive the waterways

25、 to smoothly flow, and ensure safety of navigation. In training projects, training measures are main aspects, meander cut-offs and dredging are assistant aspects.1.2.2 The sediment-little river situation of the Single shore regulating measuresRegulating works in the middle and lower reaches of the Y

26、angtze River are mainly large-scale revetment works and meander cut-offs works. Revetment works mainly include flattened revetments, dikes and dike revetment Angeles , practice indicate that riprap revetment mattress and are successful Total length of revetment construction is over 1,100 km and the

27、construction of the dike is 680 in the cross river of 1800km long through training the river in the middle and lower reaches of Yangtze river. There are two meanders cut-off, and five braided river plug fork. The building of the construction project has the advantages as follows: improvement of coll

28、apse, stability of the river, obstruction of river shift to south, protection of embankment. But some problems occurred mainly in two aspects. Firstly, there are many disadvantages as influence on the main channel and flow pattern and upstream and downstream ,left and right bands after the dike reve

29、tment built; secondly , meander cut-offs to some extent can alleviate the flood control pressure and get some shipping efficiency, but the evolution of the river bends is faster, the serious collapse not only threat agricultural and industrial production, but the efficiency of meander cut-offs decre

30、ased year by year.1.3 Channelized regulating program with the purpose of city flood control 1.3.1 The purpose and measure of city channelized regulations River channelized is to reform the natural river into the regulated channel with the parallel shores through some engineering measures. In order t

31、o insure the safety of flood control, channelized regulations and strengthening the border of river are often used in river regulated.Specific measures of channel regulations are curable River, and a narrow river. It costs high in regulating channel. In Europe and the United States. Japan and some o

32、ther developed countries, many rivers near towns and even entire sections of the river have been channeled, some important urban also have implemented the channelization in China.1.3.2 The situation of the sections in the river with the implement channelization Rhine river, an international river, i

33、s the largest water artery in Europe which runs through Central Europe, Western Europe. There are many famous city near Rhine River front. So every country takes the measures of curable river to ensure the flood-controlled safety of city River restrictions on the horizontal deformation erosion, curb

34、ing the collapse, and stabilized the river after the renovation of the Rhine river channels can reduce the danger greatly, to raise the standards of flood-prevention and also reduce the losses caused by the large amount of land. However, the river bed has attracted serious incised channels, France a

35、nd Germany, the two countries have an agreement to build water control level (Neuburg Weir). The hub has been built by the water level, and later taken to the river bed so that the river bed has been dumped stability 19781985 dumped the annual average of 167,000 km3. The shipping conditions have gre

36、atly improved by excavation of a large number of artificial canals and channelization, which promote the development of the shipping industry in the Rhine river. 1.4 The banks of navigation channel of inland river renovation measure1.4.1 The purpose and methods of the renovation measure Generally sp

37、eaking, this kind of renovation often uses engineering measures to limit the channel in a certain range in order to make sure the depth, width and gentle turning of the river in safe navigation level. There are many engineering measures of navigation channel renovation, for example using different k

38、ind of dams to clog branches of river, assure the width and depth of the river and rise water level. Besides these measures above, dredging up and cut-off are the two common assistant measures. Recently, the inland river renovation about navigation always adopts dams to cut off the bends, at the sam

39、e time, uses dredging up to limit river , make it steady and assure navigation depth as assistant measures.1.4.2 The examples of implementing the renovationThis kind of renovation planuse dams to cut off the bends with dredging up to firm the riverare wildly used on many rivers, there are some examp

40、les of this renovation. Missouri RiverThe Missouri River has plenty of water and much sand in United States. In its middle and down stream channel the renovation is mainly used to make navigation channel steady, and cut-of and dredging up are also adopted in this channel to make it without clogging.

41、 Besides, different kind of dams are built to limit river and firm navigation channel. The light permeable structures are often adopted in dams, like permeable timber pile, abandoned and shabby cars. Rockfill or concrete is the main materials in bank protection. With the renovation, the Missouri Riv

42、er now become one-bend river, and the navigation condition is improved, the depth of navigation water is deep from 1.96 to 2.1m. The Rhine River in HollandHolland is the last country the Rhine River flow across, and North Sea is its destination. In Holland the Rhine River is 170m long, and is the gr

43、eatest river in Holland. Holland not only uses embankments and controlling and conducting projects, but also uses digging channel, cut-off, making river as ditch, clean the clogging. By the end of 1850s, A huge controlling and conducting projects composed of more than 1600 dams has been finished in

44、the Rhine River according to 3 aims: first, avoid bottomland in the bank of bend outside to be eroded further more; second, rise water level especially in low water season navigation; third, decrease the effects of waves eroding banks when navigating. According to the safe navigation requirements, t

45、here are dams which are always long (some of them are even as 1/3 of river width) lies in both sides of most parts of the river no matter whether the part of river is bend or straight.These engineering measures improve navigation condition of the Rhine River largely, and promote the development of i

46、ts shipping industry. So far, the 7000t ship could pass through the river to Koln harbour, Germany. The Elbe RiverThe Elbe River slanting crosses depressions of plain in the north of Germany. It flows slowly, and the drop is low. After it passes Hamburg, it goes to the place which is 10km to the wes

47、t of Brunsbuttelkoog to pours into North Sea. The aim of renovation in this river is to limit the channel and firm the beach of banks so that the depth and steady of the river are good for navigation. In this renovation, it adopts dams to achieve its goal, and changes its navigation condition positi

48、vely. The Hanjiang RiverThe part of the river which is between Xiangfan, Hanjiang and Hankou adopts the renovation, using different kinds of dams to firm the channel, cut-off and dredge up to make it unobstructed. When the renovation is completed, safe navigation under mild low water situation is sa

49、tisfied, the channel is stable, and the condition of the channel and harbour is improved. After the renovation, the minimum depth is above 1.6m, the width of the channel is increased to 80m, the minimum bending radius is also increased ,which is from 250m to 340m. All of these mean that the 500t shi

50、p and 2000t shipping groups could pass the river, navigation guaranteed rate is up to 97%, reached a milestone in the mainstream navigation 1313km, and the part of the channel which is below Danjiangkou reaches the 4th level.According to the analysis on the examples above, the channel of inland rive

51、r adopts the renovation could limit the river, avoid channel swinging largely, assure the depth and width of the river and firm the channel. Though using dams, cut-off and dredging up to renovate the channel is an effective engineering measure, problems still exist. First, the renovation on two bank

52、s ought to work at the same time, it means a large amount of one-time investment and a long time limit for the project exist. Besides, its hard to deal with the river whose flow changes largely. Second, the investment and complexity of the project will be increased because of higher requirement of t

53、he material of the dam based on the erosion of the head of the dam. Third, the cut-off of the renovation has greatly effect on a part of river. The dam foundation and bank protection will be eroded intensely as the result of the capability of carrying sand in water is intensified after cut-off proje

54、ct shortens the channel. Further more, the deposition problem in downstream is distinct after cut-off. Therefore, cut-off project must under well control, otherwise, all these efforts wasted.1.5 The banks of estuarine navigation channel renovation measure1.5.1 The purpose and methods of the renovati

55、on measure Estuary is not only the place which is used to contain excessive water of the river, but also the junction of the river and the sea, the gateway to the land and the sea links, and even the important military bases. Sand in estuarine coast is viscous, and small in particle-size, so its ver

56、y easy to become flocculated structure. Most of estuaries are changed to sedimentation sand bar or shoal, and become the main obstacle to navigation and drainage because of deposition problems.The estuarine navigation channel renovation is dependent on renovation engineering to renovate banks, adjus

57、t flow and navigation depth. It often uses the plan on banks with dredging up measure. Thats to say, adopt different kinds of dams to limit the channel, meanwhile, renovate banks. By these efforts, the channel is confined in the range of design parameters, and its steady is assured.1.5.2 Implementat

58、ion of the river estuary channel on both sides of the river situation According to the information we were collected, clearing the important estuary of the countries in the world, has got the desired results. (一) Regulating estuary of special river at abroadMost of foreign renovations start from ren

59、ovating sedimentation sand bars. With the rapid development of international shipping industry in 1850s, the tonnage and drafts increase rapidly, and low depth in sedimentation sand bars becomes the biggest obstacle in estuarine construction. Some developed countries begin renovations such as France, United States, and Holland etc. Summarize experiences from foreign renovations, the main are: different renovation plans with different hydrologi