Cement is a magical material, but why? | Nevin Karamahmut Mermer | TEDxHacettepeUniversity

Cement and its History

• Cement is a versatile material used in construction, made by mixing cement, aggregates, and water.
• The chemical reaction between cement and water, called hydration, results in the hardening of the mixture.
• The strength of concrete depends on the cement type, water-to-cement ratio, and curing conditions.
• Cement has been used for thousands of years, with early examples dating back to 10,000 BC.
• Ancient construction techniques involved stacking stones and filling gaps with cement-like materials.
• Göbeklitepe in Turkey, dating back to 9500 BC, showcases the use of binding materials between stones.
• Ancient civilizations like Egypt, Rome, and China used binding materials in construction, as seen in the pyramids and the Great Wall of China.
• Joseph Aspdin invented cement in 1824 by heating a mixture of clay and limestone, creating clinker.
• Portland cement, named after its resemblance to natural stones found on the Isle of Portland, is the most common type of cement today.
• Advancements in material science and production technologies have led to specialized cements like fast-setting, sulfate-resistant, and radiation-shielding cements.

Cement Industry in Turkey

• Turkey's cement production began in 1912, later than its invention due to historical circumstances.
• Turkey currently has 70 active cement companies with a clinker production capacity of 96.2 million tons and a cement production capacity of 147 million tons in 2022.
• The cement industry employs 1672 people and ranks first in Europe and fifth globally in cement production.
• Turkish cement meets international quality standards and is exported to 82 countries.

Earthquake Safety and Regulations in Turkey

• The Turkish Building Earthquake Regulation has been revised seven times since 1947 to adapt to advancements in materials, production technologies, ground studies, and seismic analysis.
• Despite regulations, many people still die in earthquakes due to inadequate supervision and enforcement of construction standards.
• Proper supervision and inspection are crucial for ensuring the safety of buildings and infrastructure.
• People tend to normalize traumatic events like earthquakes, leading to psychological distress and a constant feeling of insecurity.
• Buildings younger than 50 years are generally considered safe in earthquakes, while older buildings may be at higher risk.
• The Hagia Sophia, built in 532, has survived four major earthquakes in Istanbul between 1509 and 1999 despite its age and lack of modern construction techniques.

Materials and Aging

• Materials, like humans, can experience fatigue and aging over time.
• The average life expectancy in Turkey is 70-77 years, but many people live longer healthy lives.
• Concrete is said to have a lifespan of 50 years, but this is an average and not a definitive rule.
• The author, an engineer, explains why they chose to live in a 52-year-old building despite knowing the risks.
• They find comfort and familiarity in the neighborhood where they grew up and raised their child.
• The author imagines a scenario where they live in a prefabricated house on a large plot of land, minimizing earthquake risk and ensuring their child's safety.
• They acknowledge that this scenario may not be ideal for everyone and that all scenarios have some level of risk.
• The author emphasizes the importance of considering earthquake safety when making life decisions, especially in Turkey.