656

The five expansion joints on the bridge are based on a Japanese design. This consists of three small beams forming transition slabs, which are held together by two pin-joints. In principle, the three slabs are held in the same absolute position by an equalizer, and the bridge girders are free to move backwards or forwards with temperature changes without the transition slabs moving across the expansion joint.

The three transition slabs are fastened to the bridge girders on sliding bearings. Sliding expansion rails are placed in the track, back-to-back on both sides of the joint.

The design ensures that longitudinal and rotational movements are kept separate and can take place in the track structure. The rotation of the bridge is transferred to the track structure by the two pin-joints holding the transition slabs supporting the track. The rotation of the bridge is divided so that half the movement occurs at each pin-joint.

The longitudinal movement of the bridge is distributed in a similar manner between to points on the track. Expansion of the track structure occurs at the ends of the transition slabs, shown as ‘rail expansion’ in the drawing. Expansion of the bridge girders keep changing the gap between the ballast retaining wall on the girder and the end of the transition slabs.

The two pairs of expansion rails at the abutments are fashioned as single expansion rails on the ballast. At the joints on the piers the double expansion rails are placed in the ballasted track on each side of the pin-jointed beams. Sleepers for the expansion are made of the hardwood.

The track over the pin-jointed beams rests directly on the steel beams and uses the full rail profile. Double elastic fastenings are fitted. At this point the guide rails comprise an angle section placed on the outside of each side of the track.

C………………………..

The choice of an Italian slab track design for the East Tunnel was technically the best. It was related to a Japanese design, and tests had shown that it offered excellent performance. But boring had already begun to an internal diameter of 7.7 m, and this could not be altered.

Further investigations revealed that traditional ballasted track could be used. Cleaning the ballast was the most critical maintenance operation, but it could be carried out with a modified ballast cleaning machine. Some dust was thrown up from the ballast during the initial running trials at 180 km/h, but this was easily cured by washing all of the ballast with plain water over a period of about a week.

Cleaning the ballast was the most critical maintenance operation, but it could be carried out with a modified ballast cleaning machine. Some dust was thrown up from the ballast during the initial running trials at 180 km/h, but this was easily cured by washing all of the ballast with plane water over a period of about a week.

D………………………

A drain runs to a sump at the deepest point, from where water is pumped out. It was originally intended to construct two sumps outside the tunnel using 12 m deep wells. In practice, the very difficult boring conditions meant that the location of sumps was moved to the deepest point of the tunnel. The track was raised as much as possible over a length of 100 m and placed on a concrete slab over the sump.

The track rests on the slab using a double elastic construction similar to the structure resting on the steel beams of the West Bridge. Each section of the track is fastened to the concrete slab by four bolts fixed to 130 mm glued synthetic tenons. The directly mounted track structures are embedded in 25 mm of epoxy resin.

1. Read and remember the meanings of the words and phrases.

a slab track structure — конструкция пути на бетонных плитах crushed stone ballast — щебеночный балласт

longitudinal and rotational movements — продольные и вращательные движения

expansion joint — компенсатор теплового расширения, температурный шов, компенсирующий стык, соединение с промежуточным сильфоном

held together by two pin-joints — скрепленные двумя шарнирами

held in the same absolute position — удерживаемый точно в таком же положении free to move backwards or forwards — может свободно двигаться назад и вперед sliding bearing — подшипник скольжения

longitudinal movement is distributed between — продольное движение распределяется между transition slab — переходная плита

to keep changing the gap between — обеспечивать изменение расстояния между ballast retaining wall — балластная подпорная стенка

movable rail tip — подвижный конец рельса

to accommodate the movements — обеспечить место для подвижности excellent performance — отличное эксплуатационное свойство ballasted track — балластированный путь

was easily cured by — было легко исправлено

glued synthetic tenons — приклеенные синтетические шипы epoxy resin — эпоксидная смола

to assess something from a technical economic point of view — давать технико-экономическую оценку maintenance operation — работы по техническому обслуживанию

2. Match up the words on the left with the definitions on the right.

3. Complete the sentences with one of the words.

1.A drain runs to a ………. at the deepest point, from where water is pumped out.

a)pull

b)well

c)sump

2.Cleaning the ballast was the most critical ………. , but it could be carried out with a modified ballast cleaning machine.

a)slaps moving

b)maintenance operation

c)bridge superstructure

3.The five bridge joins are ………. where the bridge girders rest on piers.

a)transferred

b)located

c)maintained

4.Each section of the track is ………. to the concrete slab by four bolts fixed to 130 mm glued synthetic tenons.

a)fastened

b)cured

c)positioned

5.To accommodate the longitudinal and rotational movements of the bridge associated with different temperatures, special ………. were needed.

a)bridge girders

b)crushed stone ballast

c)expansion joints

4. With a partner answer the questions.

1.Why was the ballasted track chosen for the West Bridge?

2.Describe the track structure on the bridge?

3.What was needed to accommodate longitudinal and rotational movements of the bridge?

4.What if the length of the bridge slab expansion?

5.How many expansion joints are mounted?

6.What kind of fastenings is used to held together transition slabs?

7.What is the reason of slab expansion?

8.How is the rotation of the bridge transferred to the track structure?

9.What is the material for sleepers used for expansion rails?

10.What was the most critical maintenance operation in the East Tunnel?

5. Read the summary of the text and say what information is missing.

The task of choosing track design was solved after various tests under normal traffic conditions. The choice fell on ballasted track for the West Bridge and slab track in the tunnel.

To accommodate longitudinal and rotational movements special expansion joints were used. They consists of three small beams forming transition slabs which are held together by two pinjoints. The three transition slabs are fastened to the bridge girders on sliding bearings.

It was originally intended to construct the sumps outside the tunnel using deep wells. Later the location of sumps was changed. A drain runs to a sump at the deepest point of the tunnel.

6.Make a list of technical aspects that you should consider when designing a bridge.

7.Read the English text below and find out:

—the function of BCR 100 bridge inspection and repair platform;

—how many people the platform can accommodate;

—units providing a remarkable reach;

—the maximum working height and a maximum lateral reach;

—the distance beyond the centre line of track where work can be undertaken;

—platform rotating angle.

Bridge inspecting platform

From Railway Gazette International,

October 2000

The BCR 100 bridge inspection and repair platform provides ready access to the underside of multi-track spans, avoiding the need for hanging scaffolding (леса и подмости), or permanent rails supporting a traveling platform for inspecting each structure. The machine was designed specifically to meet the requirement set by substantial new bridges being erected under the project to convert OBB’s Wien — Salzburg main line into a four track route suitable for 200 km/h.

The elevated working platform can accommodate three people and their power tools (электроинструменты), for which supply outlets (источник питания) are available. The reach is remarkable, thanks to the double jib (стрела) and two swiveling (поворотный) rings. The maximum working height above rail that can be reached is 23.7 m, and this extends 10 m either side of the track center. Maximum lateral (боковой) reach at lower levels is 17 m.

The most remarkable feature is the ability to reach far underneath (ниже, снизу) a span on which the BCR is standing. Work can be undertaken as far as 8 m beyond the center of track supporting the BCR in the direction away from the parapet over which the supporting arms must reach.

The platform rotates through 180°, and the vehicle’s movement at 0 to 5 km/h can also be controlled from this location. An intercom (система двусторонней связи) links the platform with the vehicle operator.

8. Read the Russian text and render it in English.

Мост на новой дороге, соединяющей Норвегию и Швецию

Мостостроение мира, №1/2002

Первое место на международном конкурсе на проектирование моста через Иддеьфьорд на европейской автотрассе Е6, входящей в состав Транс-Европейской дорожной сети занял проект арочного моста с ездой посередине, который заслужил высокую оценку как самое элегантное и в то же время самое реалистическое решение. Мост соединяет достаточно крутой норвежский берег фьорда с более пологим шведским. В связи с этим на шведском берегу предусмотрен подходной эстакадный участок довольно большой высоты. Длина пролетов эстакадной части составляет 88 м.

Арка пролетом 230 м, три одностоечные опоры эстакады и оба устоя будут сооружены из монолитного железобетона. Раздельные для каждого направления двухполосного движения балки жесткости будут изготовлены в виде стальных коробок с ортотропной плитой. При этом арка размещена между коробками балки жесткости в продольном просвете шириной 6 м. В точках пересечения арки с балкой жесткости из арки выступают консоли, на которые опираются балки жесткости. В пролете между этими точками балки жесткости подвешены к арке через каждые 23 м.

Все основные несущие элементы конструкции моста — арка, подвески и опоры эстакадной части — расположены в одной центральной «силовой» плоскости.

Поперечное сечение моста представляет собой проходную коробку из бетона класса прочности С65, люки для входа в которую размещены в уровне проезжей части. Конструкция анкеров канатов подвесок предусматривает возможность регулирования в них усилия поддомкрачиванием их из полости арки. Эти операции необходимы как в процессе строительства, так и на стадии эксплуатации. Регулирование в процессе строительства проводится после замыкания балки жесткости в неразрезную систему, для искусственного увеличения нагрузки на береговые опоры с целью предотвращения возможного отрыва концов балки в случаях неблагоприятных загружений временной нагрузкой. На стадии эксплуатации необходимость в регулировании может возникнуть при замене канатов подвесок: внезапный обрыв любой из подвесок включен в состав неблагоприятных расчетных сочетаний нагрузок наравне с динамическими и сейсмическими нагрузками.

Строительство моста будет осуществляться в условиях почти полного отсутствия подъездных дорог, поскольку задача по сохранению окружающего ландшафта являлась одной из главных в задании на проектирование. Земляные работы, бетонирование и монтаж конструкций намечено проводить с помощью 10-тонного кабель-крана, опоры которого будут установлены за устоями. Оборудование, необходимое для проведения строительно-мон-тажных работ, все строительные материалы и конструкции будут размещаться в пределах полосы отвода дороги на подходах к мосту. Бетонирование арки намечается проводить достаточно традиционными способами с обеих сторон с помощью вантовой системы с двумя временными пилонами, монтируемых позади пят арки. Перед замыканием двух полуарок в замке будут установлены домкраты для создания распора с целью уменьшения изгибающих моментов в приопорных сечениях арки.

Балку жесткости членят в эстакадной части на блоки длиной 22 и 23 м на подвесном участке. Балку жесткости эстакады ближайшего к арке участка будут монтировать плавучим краном грузоподъемностью 120 т на вылете 100 м, а остальной части — продольной надвижкой на катках с легким аванбеком методом конвейерно-тыловой сборки с площадки за устоем шведского берега. Монтаж арочной части балки жесткости намечено осуществлять по технологии, применяемой для подъема большегрузных конструкций с помощью системы гидравлических домкратов и системы тросовых тяг. Для этого на вершине арки кабель-краном будут монтироваться временные платформы.

Защиту балки жесткости от коррозии намечено осуществлять методом обезвоживания воздуха изнутри и многослойной покраской — снаружи.

Строительные работы будут начаты в конце 2002 г. Сдача моста в эксплуатацию будет приурочена к 7 июля 2005 г. — к столетней годовщине расторжения ШведскоНорвежской унии.

Use the words and phrases given below:

арочный мост — arch bridge

исчерпание расчетного срока службы — end of life expectancy крутой (пологий) берег — steep (sloping) bank

подходной эстакадный участок — approach overhead crossing одностоечные опоры — one pillar support

монолитный железобетон — monolithic (mass, in-situ) concrete балка жесткости — stiffening girder

ортотропная плита — orthotropic slab консоль — cantilever, bracket, console

несущие элементы — supporters, supporting members, bearing elements

поперечное сечение арки — arch cross-section люки для входа — access hatch

канат подвески — suspender (hanger) rope отрыв концов балки — beam tips disconnection кабель-кран — cable crane

опоры крана — crane posts пята арки — skewback

замыкание двух полуарок — two semi-arches closing изгибающий момент — bending moment

плавучий кран — pontoon грузоподъемность — load capacity

метод продольной надвижки — free cantilever method каток с аванбеком — launching girder roller гидравлический домкрат — hydraulic jack

система тросовых тяг — rope haulage system защита от коррозии — corrosion protection

метод обезвоживания воздуха изнутри — inside air dehydration method

многослойная покраска — multilayer coating

сдача в эксплуатацию — opening for traffic (commercial operation)

Test 8

I. Match English and Russian words.

II. Fill the gaps with one of the words.

1.The greatest movement that can be ………. by each expansion rail is 830 mm.

a)accommodated

b)placed

c)lifted

2.Expansion off the bridge girders keeps changing the ………. between the ballast retaining wall on the girder and the end of the transition slabs.

a)width

tunneling dead, and having been bitten once by bad geology during the construction of the nearby Furka base tunnel, the Gotthard engineers were understandably keen to know what they were letting themselves in for.

Working from a short adit into the hillside near Faido, a number of trial bores were drilled down to the area the running tunnels would occupy. These showed that the proposed alignment would miss the worst strata.

Having boosted confidence over the Piora Mulde, there remained the matter of the Tavetsch Massif — a thick section of heavily-faulted and unstable rock through which the tunnel would pass, and which could not be avoided. Four trial bores were made from around the site of the proposed access shaft at Sedrun, and these suggested that tunneling, though difficult, would not be impossible, and injection grouting should give sufficient strength to the surrounding rock to use either blasting or boring machines.

Arbeitsgemeinschaft Schacht Sedrun was set up as a consortium to built the 800 m deep Sedrun shaft. ASS comprises South African mining specialists Shaft Sinkers International working with Swiss tunneling firms Murer, Zschokke Locher, Marti Tunnelbau and CSC Impresa Costruzioni.

A 990 m access and gallery, header cavern and 80 m deep hole beneath it have been machined into the heart of Alp Tgom on the south side of Las Rueras from Sedrun. Work began at this site as long ago as April 1996, but with construction work proper now beginning, the work site has been expanded and upgraded.

Rail access

Because of the great depth of the running tunnels at Sedrun (nearly 1 km beneath the level of the FO line), it is impossible to provide the kind of direct rail-based excavation used on Channel Tunnel. With the need to minimize environmental impact, provision has been made to transport as much material by rail as possible. A 2.3 km branch has been built from a junction with the Furka-Oberalp Railway to the east of Sedrun station. This rack-equipped line drops down sharply into the Vorderrhein valley below the town to sidings alongside the river, serving the construction depot at the mouth of the Sedrun adit.

At the same time, SFr 120 m has been spent on upgrading the FO and RhB route from Chur to Sedrun for construction traffic, including signaling, power supplies and extra passing loops. The objective is to bring 90 % of materials for the tunnel by rail, most of which will be cement. Much of the tunnel spoil will be reused as aggregate for concrete for the tunnel, and for strengthening a number of local bridges, so very little will be brought out by rail.

Accommodation for the 130 workers building the shaft and a site office and exhibition centre have been provided a little below Sedrun town, but as it is a considerable drop down into the valley floor construction site, an SBB-owned funicular railway has been installed to transport workers up and down the hillside.

Workfaces

Once the shaft has been sunk into the rock down to the altitude of 547 m above sea level, expected by December this year, the job of creating workfaces for the running tunnels will begin. First, a cavern will be built at the bottom of the shaft to provide logistic space for moving equipment and spoil, and ASS is contracted to have this ready by August 27 next year.

Work will then move on to create the connecting passageways and initial tunnel sections, ready for the start of tunneling through the difficult geology to begin in early 2002. Working conditions will also be unpleasant — the high ambient rock temperature combined with water seepage will make the workface hot, humid, noisy and muddy. Adequate ventilation and rotating shift working will help minimize prolonged discomfort, but if necessary workers will be supplied with special water-cooled worksuits. Drainage will also be difficult, as water must not only be pumped up the access shaft, but also pumped uphill from the workfaces.

The twin tunnels and cross-passages running 2.2 km north descend at a grade of 0.4 %, and are due for completion by 2003; these should connect with an 11 km drive from the Amsteg access sometime in 2006.

Meanwhile, the Sedrun workers will have opened a second face, boring the tunnels south. A 4.5 km section will be dug by 2005, initially climbing at 0.4 %, it will then drop at 0.7 %, connecting with the 15 km northwards drive from Faido in 2007. Fitting out will have already begun on the outer ends of the tunnel, where construction will be easier and consequently faster. It will move to the central section later

— this work should be completed in 2010, ready for opening of the whole base tunnel in 2011.

1. Read and remember the meanings of the words and phrases.

access shaft — входная шахта cavern floor — дно пещеры

layer of weak rock — слой слабого грунта exploratory bores — разведочные скважины

varying enormously in its structure — очень неоднородные по структуре water bearing rock — водоносные грунты

base tunnel — основной тоннель a trial bore — пробная скважина to drill a bore — бурить скважину

heavily-faulted and unstable rock — сильно нарушенный и неустойчивый грунт injection grouting — нагнетание раствора

a mining specialist — горняк

a tunneling firm — тоннелестроительная фирма header cavern — главная (входная) пещера

to machine into — врубиться, врезаться

direct rail-based excavation — землеройные работы рельсовым экскаватором to drop down sharply — резко опускаться

extra passing loops — дополнительные объездные пути to sink the shaft into the rock — пробурить шахту prolonged discomfort — длительные неудобства water-cooled worksuit — костюм с водяным охлаждением the mouth of the adit tunnel — вход в штольню

drops at a grade of 0,4 % — опускается с уклоном 0,4 %

2. Match up the words on the left with the definitions on the right.

3. Complete the sentences with the words.