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 first bridges were upheld by arches, such as flat stones or tree trunks laid across a stream.

2. Materials to construct first bridges were available and ample.

3. Clapper bridges were built with long slabs of stone and with rocks or blocklike piles of stones.

4. Bridge construction work in the Roman Empire was done by slaves, soldiers, or natives, so labour costs were few.

5. Circular arch form used by the Romans served to make spans much longer than stone beams.

6. The Romans developed the cofferdam allowing piers to be built on rocks.

7. Crisscrossing of the logs helped to reach adjacent piers.

8. Old boats filled with stones were used as cofferdam-like foundations.

II. Answer the following questions:

1. What are the main types of bridges in the ancient world?

2. What was the principle of a simple beam bridge?

3. What is a clapper bridge?

4. The Romans developed bridge construction. In what way?

5. What was the purpose of the cofferdam? The construction of what type of bridges requires the cofferdam?

6. What is the basic design of a cantilever bridge in the Ancient Asia?

III. Define the type of the bridge:

a) beam a) beam a) beam

b) cantilever b) cantilever b) cantilever

c) arch c) arch c) arch

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