Modern technical problems in bridge building

Superstructure. For establishment of designed conditions of such large bridge that has a central span as long as 150m, various studies were made. Main structure was designed based on the Design Specifications of steel road bridges. As for the slab floor structures, in order to cope with the passage of container cars, they were made strong enough of conducting load tests using large containers. The strength against wind and earthquake was examined by the results obtained from the studies of the project. The wind stability of doubledeck structure was studied by wind channel model test. Photo-elasticity model tests were applied to investigations of stress conditions in the portion where the members intersect. Considering the influence of salt particles on the steel members of the bridge to be constructed over the sea, acid resisting steel and paint of a special type were used for prevention of corrosion. In erecting the central span over the sea, in view of time limit and passage of vessels, large block method was adopted.

Substructure. A detailed soil survey was performed because of rather severe requirements for substructure such as gigantic load and pressure transmitted from superstructure. The survey includes large-diameter boring, loading tests of deep strata. Pneumatic caisson method was executed for central main piers, and bearing capacity of foundation at the bottom of the caisson was confirmed through water-TV camera brought into the working room of the caisson.

EXERCISES

I. Pay attention to the pronunciation of the following words:

Pneumatic, channel, diameter, earthquake, special, gigantic

II. Translate the attributive groups:

Stress conditions, detailed soil survey, large-diameter boring, pneumatic caisson method, central main piers, wind channel, wind channel model test, large block method, photo-elasticity model test, slab floor structure.

III. Find the participles II in the text and translate the sentences into Russian.

IV. Translate the sentences into English:

1. При сооружении центрального пролета применили новый метод. 2. Принимая во внимание коррозию, металлические элементы моста покрывали специальной краской. 3. Чтобы исследовать условия напряжения были проведены специальные испытания. 4. Для определения аэродинамической устойчивости были проведены опыты в аэродинамической трубе. 5. Проведенные испытания подтвердили правильность проекта. 6. Так как испытания дали хорошие результаты, началось активное строительство моста.

V. Complete the following sentences according to sense:

1. A detailed soil survey was performed because of… 2. A special type of painting was used for… 3. Bearing capacity of foundation was confirmed in order to… 4. The strength against wind and earthquakes was examined because…

VI. Speak about technical innovations which were used in bridge building in Japan.

VII. What technical inventions are used in modern bridge building:

a) in our country

b) abroad

VIII. Read the text without a dictionary:

THE KOBE BRIDGE IN JAPAN

The Kobe Bridge was built to meet rapid increase of trade and modernization of freight circulation in Kobe Port. Kobe Bridge of four-lane and double-deck structure, connecting the Island with the New Kobe Port, serves for a traffic of 50 000 vehicles per day between the port and the cities of Japan. The Bridge spans a channel of 200m wide; it is a three-span continuous arch bridge, the largest arch bridge in Japan.

Substructure must withstand severe physical conditions, as they support a great load transmitted from the superstructure.

In order to know characteristics of soil various investigations and tests have been made.

IX. Make a plan of the text and retell it.

X. Organize a conference on bridges. Make reports on the following subjects:

1. Girder bridges

2. Cantilever bridges

3. Arch bridges

4. Suspension bridges

5. The last achievements in bridge building

6. Technical innovations used in Japan

7. Wonderful bridges in St-Petersburg

8. Interesting bridges in Moscow

IX

Дата добавления: 2015-08-27