(CFRP)

Master the key terms and head words.

carbon — углерод composite — составной, слож­ный fibre — волокно hoop — обруч plate — плита, лист

to bond — соединять                    Sweden — Швеция

per cent - процент                     South- East Asia - Юго- Восточ-

per meter - на метр                           ная Азия

per hour - в час                         the United Kingdom (UK) - Объ-

Middle East — Средний Восток       единенное Королевство

127. Give the Russian for the following combinations; mind the Gerund.
tower under dead, live, wind, and thermal loading
rehabilitating dams and bridges

increasing the durability of concrete strengthening methods of rehabilitating silo towers

Read the combinations. Translate them from Russian. plate iron — листовое железо ring foundation — кольцевой фундамент scaffolding of girders — помост из балок

128. Translate the Russian words into English.

1. (Глубина)______ of carbonation and chloride content...

2. (Глубокие)______ vertical and horizontal (трещины)_____ ...

3. Carbon-fibre-reinforced-polymer (пластины)_____ ...

4. Successful (использование)_____ of CFRP scaffolding...

129. Give the Russian for the following terminological combinations,
concrete rings         hoop direction        steel plate bonding

Read and translate the article.

The use of composite materials for the strengthening and rehabilitat­ing of bridges, towers, dams, and other concrete structures is gaining pop­ularity. The reason for it is the fact that the use of composite materials turned out to be advantageous over other strengthening methods relating to durability, workability and whole-life costs of concrete structures. Projects based on the use of carbon-fibre-reinforced-polymer plates are being realized on a number of silo towers and other structures in Russia and Sweden. The technology of CFRP plates started to be popularized also in the Middle East and South-East Asia.

Not long ago CFRP plates have been used for the purpose for in­creasing the durability of the existing concrete structures in the United Kingdom construction industry. The plates successfully serve as an alter­native to other traditionally used methods. During the last two years more than 150 bridges and other concrete structures around the United King­dom were rehabilitated with CFRP plates.

70

Essential Course

Unit Eight. Concrete

71

Strengthening a 30-year-old, 65 m tall, tower may serve as an exam­
ple of successful usage of the plates. The work started with detailed analy­
ses of the tower under dead, live, wind and thermal loading in order to find
out the present durability of the tower. The detailed inspection revealed
deep vertical and horizontal cracking in many places on the tower. Also
tests were carried out to reveal the depth of carbonation and chlorine con­
tent in the concrete. And in order to rehabilitate the tower there were pro­
posed the following three variants:                                     f

1. to use CFRP bonding in the hoop direction;

2. to use steel plate bonding in the hoop direction;

3. to add concrete rings along the height of the tower.

The first of the three given variants was considered to be most advan­tageous over the other two. First of all because it would require only 25 days while the other two would require not less than 90 days. Besides the light weight of the CFRP plates did not require strengthening work on the foundation of the tower. So the usage of the CFRP plates also made it necessary to use the least amount of scaffolding girders in order to carry out the work. Of importance is also the fact that the use of CFRP strength­ening made it necessary to use only two 160 x 1.8 mm plates per meter throughout the height of the tower while the use of steel plate bonding required two 300 x 7 mm plates per meter. Naturally, this fact considerably lowered the cost of the works.

130. Finish up the sentences. Choose the proper combination from the combinations
given below.

1. The CFRP plates are used for the purpose of______________

2. CFRP plate bonding is applied in the____________________

3. Concrete rings are added along________________________

a) the height of the tower

b) increasing the durability of the structures

c) hoop direction

131. Pair work. Read and translate the questions. Put them to your groupmate and let
him/her answer them.

1. What material is gaining popularity for rehabilitating concrete struc­tures?

2. In what countries is the technology of CFRP plates being realized?

3. What tower was strengthened with the plates in the United Kingdom?

4. In what way was the present durability of the tower found out?

5. What did the detailed inspection of the tower reveal?

6. For what reasons was the first of the three proposed variants chosen?

132. TVanslate the article in writing. Use a dictionary if necessary. New Corrosion Protection The use of epoxy-coated reinforcement prolongs the service life of reinforced concrete structures. Besides it delays the need for repairs of replacement. Epoxy-coated reinforcement is being used successfully in bridge decks, parking garages, highways, plants, ports, and marine struc­tures. Another advantage of reinforcement is that it costs less than other identical systems.