Regard railroad as the engineer, I will answer this question, wrong place, ask experts point out mistakes so that they can be corrected.
Why to fine jade city channel did not build big bridge to connect Guangdong and Hainan? Actually, this friend is not the first query the person of this problem, at least 20 put forward to be built in channel of city fining jade with respect to somebody before New Year more cross Hai Daqiao or the tentative idea of chunnel, did feasibility research. But condition of nature of channel of city fining jade and geological condition are very abominable, want to build the project that cross the sea in that area, difficulty special big. We consider channel of city fining jade to build the program of a few technologies of project of the traffic that cross the sea back and forth below, and the feasibility of plan.
[the characteristic of channel of city fining jade]Channel of city fining jade belongs to our country Nanhai, be located in between island of Hainan of peninsula of city of Guangdong province thunder and Hainan province, situation is very fundamental, it is communication north bay and Nanhai not only the maritime corridor of medium, the eastpart part, also be Guangdong the maritime traffic shortcut to Hainan island and Vietnam and other places. Channel of city fining jade is known as " gold aqueduct " , it is one of China's famous 3 seas gorge, integral whole place is worn at Nanhai mainland on, marine landform is all around the low long and narrow and rectangular basin between high school, thing length makes an appointment with 80 kilometers, north and south is average width is close 30 kilometers, 40~160 of depth of water rice, channel center depth of water is about 80, 100 meters. Here also is our country suffers typhoon and monsoon to affect one of the most serious areas, the intensity of the intertropical cyclone of pass through the territory of a country of channel of city fining jade is very high, the strong convection weather of this kind of extreme brought blast and torrential rain, the typhoon with pass through the territory of a country is landed every year to have 2 ～ in channel of city fining jade 3, 25% what occupy the front to land amount of our country typhoon about, great to crossing sea project to affect.
Research designed personnel to do many analysis research, by traffic Department of Transportation, former railway ministry and Guangdong, Hainan two provinces organize a work out to finish jointly " channel of city fining jade crosses sea project to plan to study a report " , offerred a few feasible program that cross the sea, include to hang all alone to cross a variety of mode such as channel of Hai Daqiao, in suspension, heavy canal channel and chunnel.
(1) hang all alone to cross Hai Daqiao -- the channel of city fining jade of the design crosses Hai Daqiao to will divide fluctuation two, among them the design speed per hour of railway bridge is horary 160 kilometers, speed per hour of highway bridge design is horary 100 kilometers. After big bridge builds, drive span channel of city fining jade needs 20 minutes only, train passes through to also will be compressed in 10 minutes of less than, and at present support ferry carries channel, await boat and time of sail a boat to need 5 hours about, economic time is very considerable. But because the typhoon is much,channel of city fining jade is had, span big, depth of water is big, geological the characteristic such as conditional difference, bridge program accepts restriction more, technical difficulty is great, technical economy is improper as a result quite, and bridge is jumped over grow, the effect that suffers a typhoon is bigger, the project is more arduous, investment estimation is as high as 140 billion yuan.
(the suspension bridge that cross the sea)
(2) suspension channel -- be called again Archimedes bridge, it is a kind of new-style underwater traffic structure, it is the balance action of the flotage that carries water and anchorage firm force, make channel in suspension proper in water deepness, the effect that this kind of channel suffers depth of water and marine landform landforms, geological condition is lesser. Below circumstance of same optional location, provide channel and benthic channel than sinking, gradient of suspension channel axial is lesser, and overall length is shorter (can see apparently from inside attached drawing) . Outside removing extreme weather condition, the influence that the traffic in suspension channel runs state of gas getting a day is minor, more intelligence is changed, lesser to surroundings influence, do not affect condition of be open to navigation or air traffic, won't destroy local landscape. Have higher sexual price to compare, the cost of tube unit length wants than other and traditional channel and bridge low, and total cost won't rise as the addition of span. Plan of channel of in suspension of choice of channel of city fining jade is appropriate.
(suspension channel)
(3) heavy canal channel -- heavy canal channel is by a certain number of prefab canal paragraph respectively float carries the spot, heavy put the geosyncline that has dug beforehand inside, join its each other in underwater and become. The crucial technology of construction of heavy canal tunnel is excavate of underwater radical chamfer, canal paragraph make, float carry, heavy put and contact is waterproof. Sea floor of channel of city fining jade is deep water basin, the deep cistern that the axis in the basin is 114 M of ～ of 80 M of depth of water and two side are north and south more steep bank, the biggest tall difference achieves 70m, want to build heavy canal tunnel, be about to fall dig steep bank the following, the project is very arduous, do not suit channel of city fining jade.
(heavy canal channel)
(4) chunnel -- this kind of channel is to pass mining of aegis compose machine, bury deep big, channel is long, create investment thereby big, time limit for a project is long. The layer of channel of city fining jade basically is earthy layer, if use construction of aegis compose law, need to build artificial island to overhaul aegis compose machinery in order to have in channel, increased construction difficulty and investment. Chunnel is additionally right of undesirable and geological circumstance forecast reach ventilated demand is very high, in depth of water bigger case falls, chunnel should grow than suspension channel severalfold, even 10 times, invest apparently should compare suspension channel a lot of taller, also do not suit channel of city fining jade.
(chunnel)
The place on put together is narrated, channel of city fining jade crosses sea traffic project or with suspension channel plan the most appropriate. Of course, use which kinds of plan finally to still be at present in the controversy.
