Comprehension check. I. Decide whether the following statements are true or false according to the text:

I. Decide whether the following statements are true or false according to the text:

1 The lifting process is the most complicated in bridge construction.

2 Care should be taken during the lifting of the suspended span.

3 Accidents may happen in spite of correct instructions.

4 The temporary rigid connections were removed when the cantilever arms were constructed.

5 The stress in the top chord of the beam completely disappears.

6 Cranes are widely used to lift sections of. prestressed concrete bridge.

7 One of the most popular methods in bridge construction is to turn the span into an arch until closure is complete.

8 The casting of each segment is done on the construction site.

9 Each segment is placed after steel prestressing wires are fitted to hold it in position.

10 The post-tensioning method is called so because the stress is added before placement.

II. Answer the questions:

1 Why are heavy objects suspended in space dangerous?

2 What do incidents show?

3 How was Forth railway bridge constructed?

4 When were temporary rigid connections removed?

5 When does the tending moment at the join completely disappear?

6 How are some continuous box girder beams constructed?

7 What are the methods of lifting sections of a segmented prestressed concrete bridge?

8 What is the casting of each segment done?

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