Transportation system can be serious job for states, particularly, seaside states or metropoliss that near the sea. During the twentieth century, railroad transit has been going of import peculiarly for crowded and developed metropoliss due to air pollution, traffic congestion, and so on. Hence, railroad transit systems start to better.
Timess have changed, nevertheless, and what was impressive in the early twentieth century, was shortly going less and less satisfactory. Airplanes and private autos were already offering transit options at every graduated table. Given the force per unit area of competition, the railroad had to overhaul and better, particularly as respects speed decrease of transit costs and better administration and betterment of services offered.
In these conditions, in order to develop transit systems, Turkish authorities decision makers have started to emphasis on railroads. First and foremost, they wanted to happen a solution for the traffic jobs of Istanbul. It would be possible to traverse the sea resistance ( tube tunnels ) or aboveground ( Bridgess ) . Istanbul presently has two Bridgess to traverse the east-west line but they did non work out the traffic jobs. On the contrary, the traffic congestion has been going more and more of import around the country of Bridgess. Besides this traffic has caused environmental pollution. Turkish authorities made a determination about submarine tunnel undertaking and started to use it. The name of the undertaking is ”Marmaray ” and the most important portion of this undertaking is how to traverse the Bosporus side. As Balta ( 2008 ) stated that the completion of immersed tubings under the Bosporus, portion of the undertaking to link Asia and Europe side of Istanbul through an belowground railroad, has been praised by Prime Minister Recep Tayyip ErdoAYan, naming the Marmaray undertaking, foremost planned in 1860 by Ottoman governments, the going existent of a 148 old ages dream. Lykke S, Belkaya, H, who are the important positioned applied scientists in the undertaking, province that ‘the intended intent of the Marmaray Project is to supply bi-directional, safe, robust, dependable, comfy, lasting, cost-efficient and uninterrupted train transit of riders and cargo throughout the Istanbul country of Turkey, on both sides of every bit good as under the Bosphorus Strait for a design life of 100 old ages ‘ . ( ITA/AITES Accredited Material Marmaray undertaking: The undertaking and its management,2005 )
it will be shown in this paper the background of the Marmaray undertaking in both parts ; general background, proficient background in the subdivision 2. Then it will concentrate on the immersed tunnel methods, comparing the other methods, and implemented undertakings which are used this technique in subdivision 3. After that it will demo some reappraisal about the method and procedure of the execution in the undertaking in subdivision 4 and eventually, doing rating of the overview in subdivision 5.
2. Marmaray undertaking
2.1 General Background of the undertaking
The Marmaray undertaking, which is one of the universe ‘s of import undertaking, is complex and major substructure undertaking being implemented in the universe. This undertaking is non the first crossing undersea undertaking in the history. This thought foremost was thought by Sultans of Ottoman Empire, Abdulmecit. In item, that project consisted of two chief construction ; several undersea columns and tremendous tubings. Besides during the Ottoman Empire periods, many of the same undertakings were prepared. In the twelvemonth 1902, the most important undertaking, Tunel-i Bahri, was prepared. Harmonizing to this bill of exchange, there were 16 columns which were fixed the sea degree.
Figure1: the first prepared projected in Ottaman Empire ( sourced from www.marmaray.com )
Until this undertaking started, many undertakings improved and executed in the different topographic points. Furthermore, undertaking applied scientists had made assorted mistakes. Therefore, undertaking directors have become more experient over clip by measuring the mistakes of others. In 1985, Underground transit systems started to be important. And with authorities support, the first comprehensive feasible survey was reported. In 2003-2004, this study was updated for the concluding theoretical account. This undertaking will represent long term solution to most of import job, transit of Istanbul. Double lines have a capacity of 75.000 riders per hr so the traffic congestion will be reduced on the Bridgess. In connexion with this, the air pollution and CO2 release in Istanbul will diminish. Furthermore, harmonizing to this graph, while railroad use were 3.6 % before the undertaking, Istanbul will make the developed metropoliss railway transit use.
Figure 2: The importance of railroad transit ( use of the railroad transit per 100 people ) ( sourced from DLH records )
This undertaking offers many different challenges. First and first, the immersed tunnel under the sea will be deepest building with 58m. In this instance, geographical construction was going of import issue. Throughout the Bosphorus there are two different flow bed ; Karadeniz -Marmara sea, frailty versa. Therefore, tubings will be affected two sides. The other of import one is that building plants can be affect Bosporus traffic, approximately 50.000 ships utilizing the way of north- South in the Istanbul sound each twelvemonth. The last challenge is that the country of Istanbul had experienced seismal event with magnitude 7.5 and it can be grounds about future seismal motion.
2.2 Technical background of the undertaking
This undertaking consist of 4 different portion ;
Part 1: Consultation contract
Part 2: Undersea tubings and construction of station ( BC1 )
Part 3: Revision of significant train station ( CR1 )
Part 4: Geting new railroad vehicle ( CR2 )
Each portion of the undertaking is given in a different company which are experts of their field. As it is seen the above, the undertaking divided into 4 different portion. This paper will concentrate on submarine tubings and construction ( portion BC1 ) and besides it will give some information about the other parts. Nowadays, the portion BC1 has merely finished and the other parts will be start orderly. In CR1 portion, there are 40 Stationss in this undertaking ; 37 of them will be upgraded or rebuilt aboveground, the other three of them will be constructed belowground. These Stationss will dwell of centre platform type Stationss and the minimal platform length is 225m. If peak capacity can be considered, commuter rail system presently will transport about 10.000 rider and upgraded rail will transport estimated 75.000 rider per hr. The maximal operational velocity will be about 100 kilometers per hr. Due to the short distance Stationss, the expected velocity will be merely 45km/hour. The whole travel clip from Gebze to Halkali will be about 104 proceedingss. During the peak times, trains will go forth the station every 120 seconds. ( Sourced from ”www.marmaray.com ” )
Harmonizing to the undertaking, the sum immersed tubing tunnel length is about 1.4 kilometers with connexions which is consist of detached two railway and Centre wall. Tunnel was comprised 11 tubings ; each tubing was about 135m and produced as a prefabrication in Tuzla Offshore Element Fabrication Site. After the production procedure, each tubing was floated to the undertaking location topographic point and immersed by assisting particular vehicles. Then immersed tubings were connected between them and fixed the sea land. Figure 3 and figure 4 show to item of the component 11 which is the portion of tunnel and positioned whole tubing program and profile severally.
Figure 3: the program of equiping for element-11 ( Sourced from Minister of transit record office )
Figure 4: immersed tubing tunnel program & A ; profile ( Sourced from Minister of transit record office )
3. Analysiss of submarine tunnel methods
3.1 Criteria of taking suited method
There are several sort of standards to pick the best solution. In order to compare the different crossing methods, it is necessary to put an riddance standard. The most of import of these are ;
*Although it is theoretically possible to construct a peculiar type construction for every state of affairs, execution of this can be really expensive and unlogical. So many solutions can be eliminated and preferred the best 1. This intent, it is non logical to utilize tube tunnel methods in shallow H2O alternatively of Bridgess.
*Another standards can be building operating, care and fix cost. The entire costs of the tunnelling are higher than Bridgess. Due to the fact that illuming and airing. Besides the same state of affairs is valid for fix and care. Steel building which is used for span edifice by and large needs more care than concrete constructions.
* the user costs can be important state of affairs for pick of the method, particularly vehicles spend clip for, fuel and money in traffic. But it is non taken into history because it does non has to be paid by authorization supplying the money for the nexus.
* Besides safety, Environmental impact ( air pollution, noise, ocular invasion ) are well of import.
3.2 Criteria Of The Earthquake And Impact For The Tunnel
Figure 5: Turkey Earthquake Zones Map ( sourced from “ www.marmaray.com ” )
As it can be seen from the map that Istanbul is located in the 20 North Anatolian Fault Zone, which runs from E to west lines of throughout the Marmaray Sea side. It can be seen from the map that the topographic points which are painted ruddy are included most hazard and evaluated others ; tap, yellow, white severally. In the undertaking hence possible temblor hazards must be taken into the history. Particularly during the constructing of belowground constructions, it must be careful about the safety. In this instance, many safety topographic points and exigency exists must be constructed in at that place.
Severe temblors can do major harm to large infra construction undertakings if the design does non sufficiently take the effects into history. Therefore, the most sophisticated computing machine based theoretical accounts will be utilized on the Marmaray Project, and the best experts from America, Japan and Turkey will be involved in the design procedure.
( sourced from www.marmaray.com )
It could be indicated that the Kobe and BART tunnel located in the most common temblor zone in Japan and USA. These are good illustrations of how tunnels could be constructed in a lastingness. On the Marmaray Project, there were many amassed information from geological, geotechnical, hydrographical and meteoric probes, and the most modern engineerings of civil technology engineering have been used for the design and building of the tunnels. Correspondingly, More safeguards should be taken for temblor. The most of import step for tubing tunnel is that the unifying points of the tubings were built with gum elastic. So it can amortize the energy which come off during the temblor. In this intent there were many experts from America and Japan involved the building procedure and surveies. In this portion of the undertaking experiences of American and Japan people was used. ( partly sourced from “ www.marmaray.com ” )
3.3 Use of Selection Criteria
A pecuniary value can be determined with many of the standards. The other standards can be
divided into many parts, e.g. noise, and some of standards can merely be assigned a qualitative value. Assorted systems can be used to measure these are non comparable worth or at minimal monetary value to supply a manner to show them to the determination shapers. ( Burrowing And Underground Space Technology, cited in Pera et al 1983 )
3.4 the chief features of methods
Underwater tunnels are by and large preferred topographic points which are non allowed to build any type of Bridgess. There are three options methods for traversing the H2O ; Bored tunnels, drifting tubing tunnels, immersed tubing tunnels.
3.4.1 Bored tunnel are by and large constructed when the land or waterbed is allowed to unearthing and incursion for deep tunnels. In this intent, there are two chief methods could be used. The first 1 is presently the frequent methods by utilizing Tunnel-Boring Machine is common known TBM method. The other method is that it is normally known Open -Close method ( DBM= drilling- blaring method ) . However TBM with a round surface drill dirt, it does non make a strong wall. So this method is merely suited for included difficult stone. ( TCRP Report/NCHRP Report 2006 ) .
3.4.2submerged drifting tunnel method is a new manner of constructing method tunnel besides known as an Archimed. There are many illustrations which are built this manner in the universe. Particularly Norse and China have implemented undertaking. In this manner, the executing topographic points need less significant sea bed. Tubes are non buried into the sea bed oppositely from the other methods. Therefore, the entire undertaking budget could be reduced. However, this methods could be used deep Waterss due to sea transit etc.
( Kartaltepe, N, ( 2008 ) , Preliminary design and analysis for immersed tubing tunnel across the Izmir Bay, cited Hakkaart, et al.1993 ) .
3.4.3 An immersed tubing tunnels consists of several combined tubings, each frequently 100 m long, which are built with a prefabricated on the land, that are finally enlisted below H2O to go concluding signifier. And so each portion of tunnel, tubings, are floated and brought to project location by puller ships. In this instance, conditions conditions as speed of the air current and watercourse flow of part are going really of import. After that, tubes are going lower without physical force. ( tubings are lowered with fulfilled the H2O armored combat vehicle which is embed in the tubings and after finished this operation this H2O are thrown off from the tubings ) Baltzer and Hehengeber claim that it could be risk to turn up on the sea beds which include soft sandy, silty or alluvial dirts H2O depth more than 60m. ( Kartaltepe, N, ( 2008 ) , Preliminary design and analysis for immersed tubing tunnel across the Izmir Bay. Izmir )
18.104.22.168 Analysiss of traffic intent implemented undertakings
The technique that was used in the Marmaray undertaking to traverse the sea, immersed tunnel, has been developed since the first portion of 20 the century. There are 108 immersed tubing tunnels in the universe. About their location,48 of them in Europe, 27 of them in North America, 20 of them in Japan, 9 of them in South Asia ( except Japan ) and 4 of them in other states. The first illustration of the immersed tubing tunnels is building in Turkey is the Marmaray Project that is being built on the Istanbul Bosporus Waterway. It will be the deepest immersed tubing tunnel in the universe when the building is completed ( Marmaray 2007 ) .
The firs tunnel which was built for traffic was constructed in USA, under the Detroit river. It consisted of 11 tubings, each tubings length was 80m and wholly tunnel length was 800m. It was built 24 deeper from the surface of the river.
The first immersed tunnel edifice in Europe was Freidrichehafen, was built in Berlin in Germany in 1927. It consisted of 2 tubings and entire length of tunnel was 105.8m. It was shorter tunnel comparison with the other illustrations.
On the other manus, in 1941, the of import tunnel which was presently utilizing as a main road was built in Holland, Mass tunnel. The length of the tunnel is 584m and it consisted of nine tubings. And each tubings 61.35m long, 8.35m in tallness and had a breadth of 24.77m. This tunnel was kept closed during the universe war 2 by Holland. Harmonizing to Milestone in Tunnelling: Rotterdam ‘s Maas Tunnel Celebrates its Fiftieth Anniversary, this tunnel was a landmark in immersed tunnelling due to the fact that its historical significance and proficient accomplishments. Besides the most successful interior decorators, applied scientists, directors and metropolis state involved this undertaking and contributed to burrow which exerted first-class criterions that still keeps.
It was an of import point to detect that pressurised concrete which is used for constructing more stable construction were used for the first clip in the building of an immersed tubing tunnel in Cuba in 1958. The entire length of the tunnel was 520 m. The lengths of the tubes mean 100 m, the tallness was 7.10 m. and the breadth was 21.85. This main road tunnel was built 23 m under the sea degree.
The Dees Tunnel in Canada was the first undertaking which is taken history the temblor
tonss was constructed 22 m under the surface of the sea, with a entire length of 629 m. It
includes 6 concrete tubings and each 1s length was 104.9 m, tallness was 7.16 m and breadth was 23.80m. The Scheldt E3 ( JFK ) Tunnel, built in 1969 in Belgium, had used elements ( tubings ) ,
which had of all time been constructed of the immersed tubing tunnels history.
The breadth of the prestressed concrete boxes was 47.85 m, tallness was 10.1 m, while the
length varies between 99 m and 115 m and the weight of each tubing was about 47000
dozenss. River currents of up to 3.0 m/s. Tides with a average scope of 4.8 m and a maximal scope. So it can be possible to state component ‘s weariness and corrosion were going more and more of import.
The Bay Area Rapid Transit ( BART ) Tunnel was the longest bing immersed tubing tunnel in the universe. The tunnel was constructed between San Francisco and California constructed in 1970. The tunnel length was 5825 m. and it had been designed as a railroad tunnel. This tunnel consisted of 58 tubings and each had a length of mean 110 m, and tallness of 6.5 m, breadth of 14.6 m. At a maximal deepness of 41 m under the sea degree, in its clip and country it was the deepest tunnel. ( Grantz, et Al. 1993 )
22.214.171.124 Other Applications of the Immersed Tube Method
The executing of the immersed tubing method is non limited to traversing the H2O for traffic intent, as is demonstrated by the undermentioned illustrations.
1 ) In 1966, there was 1600m long tube line was built near the river crossing in Rotterdam. The units, for this intent, were prefabricated and transported through the unreal canals and used for building of the station.
2 ) At Gosport ( U.K. ) , sea outfall into the Solent was built with utilizing the immersed tubing method in 1980. Its length was 1.1km.
3 ) Besides in 1985, this method had been used for mercantile establishment and consumption of chilling H2O for power workss in Tarragona, Spain.
4 ) At Karmoy, Norway, The 590-m-long concrete immersed tubing method was used for the shore
attack of two gas grapevines. It was created to protect and steer the grapevines through the shore country.
4. DISSCUSSA°ON AND RESULT
Transportation system is bit by bit going more and more of import for both developed and developing states. As a consequence, many transit undertakings have been applied, particularly in European and North American states. As it is known, Istanbul is the Centre of Turkey and the most crowded the metropolis, with 15 million people. The general overview obtained at the terminal of the survey have been evaluated as below
1. This survey is based on comparing of the Bosporus sea traversing methods proposed in the Marmaray undertaking and included its background information. Besides this survey purposed to demo challenges and benefits of the undertaking.
2. After the Marmaray undertaking started, the method choosing of the sea crossing was a problematic state of affairs. In this instance, there were three possible methods ; submerged natation, bored tunnel and immersed tunnel methods. Harmonizing to approved standards which are cost, quality, lastingness and so on, if the general use methods are compared, the best pick can be determined to be immersed tube tunnel. It was the right pick for these conditions.
3. This paper has investigated a figure of different illustrations of immersed tunnel undertakings and the status which need to be met. These are challenges, locations and benefits. Besides the determination shapers have a opportunity to compare their work with other undertakings.
4. The of import thing should be notice that possible temblor tonss has been taken into the history and whole undertaking calculations have been calculate. Rigorous temblors can do harm on the undertaking. Many computing machine based theoretical accounts have utilized on the undertaking, and experts from Japan, America and Turkey involved the designed procedure.
As it is shown that there are three chief methods utilizing for sea crossing ; Bored tunnel, Immersed tunnel, submerged drifting tunnel. Bored tunnel method is used for shallow H2O. And besides sea land must be steadfast and non to include flaxen, mud dirt. The Bosporus side has sandy and mud dirt. In this instance, it is non convenient method for Marmaray undertaking.
Submerged drifting tunnel method is normally used method last old ages. It was used foremost in Norway to traverse the river. However, it is non suited method for Marmaray undertaking due to the undertaking deepness, chance of the temblor and high cost.
The dream of the 146 old ages Marmaray undertaking and the types of the railroad burrowing methods, particularly immersed tubing tunnel method, explained in this article about the historical background, developments and use. There are many illustrations of the immersed tunnel method in the universe, about 70 per centum of them are located in Europe and North America. In this instance, it would be mentioned that this method is used normally in these country. The one of biggest and still proceeded building is Marmaray undertaking. This survey clearly shows that the most suited crossing method is immersed tunnel methods for this undertaking.