Exercise 1. Put the sentences containing the main ideas of each paragraphs in a logical order according to the text.
In 1903, A. O. Elzner completed the first reinforced concrete skyscraper using Ransome's twisted steel bars.
The use of concrete was lost for centuries until discovered again in the nineteenth century. Americans and Europeans used it in large warehouses, factory buildings, apartment buildings and homes.
The first users of concrete date before 1200 BC and include societies like the Phoenicians, Minoans, and Egyptians, to name only a few.
Designing and constructing any concrete structural system architects and engineers should take into account such material properties of concrete as its strength, durability, forming techniques, hardening characteristics, nature and extent of reinforcement, aesthetics and much more.
In 1884, E. L. Ransome patented the system of twisting square steel bars to increase strength and adhesion to concrete.
The introduction of composite construction to tall tubular buildings in the 1960s has paved the way for supertall composite buildings.
Exercise 2.Find proper answers to the questions listed below.
1. What are the basic structural materials of construction having existed for a long time in the history of civilization? Which of them is the youngest one?
2. Why was the use of concrete lost for centuries?
3. Why is the 1876 Centennial Exposition in Philadelphia considered the baseline in the history and development of the skyscrapers?
4. How were specimens of reinforced concrete exhibited at the Centennial?
5. When did the discovery in a modern sense of reinforced concrete take place?
6. Who contributed greatly to its development?
7. What buildings were considered appropriate uses of concrete at the beginning of the 19th century?
8. What century does the history of concrete high-rises belong to?
Exercise 3.Find in the text the information about the most important innovations which made concrete a good choice not only for factory and low-rise apartment buildings but also for high-rises.
Exercise 4.Make up a short summary of the text.