Nurhan Gürel
CemenTürk Editor-in-Chief
Foreword
Cement is one of the basic building blocks of the modern construction industry. Since its very first use, cement has not only been a building material, but has also pioneered breakthroughs in the engineering and architecture. Throughout its historical development, it has constantly been rediscovered and developed further by different civilizations, undergoing many evolutions.
In a series of articles, we aim to provide readers with a comprehensive overview of the importance and evolution of cement in the construction industry, from historical perspective to contemporary technologies. Through different series of articles, the first is presented below, we will try to explore the journey of cement from its primitive forms when it was first used in prehistoric times, to the discovery of modern production techniques with the industrial revolution, to the innovative types developed today for sustainable structures.
Prepared for building industry professionals, architects, engineers and anyone interested in this field, this article will be a source of historical information as well as an inspiring guide for future innovations as it shed light on the historical development process of cement.
1. Introduction
The word “caementum”, the etymological origin of the cement, was first used by Roman architect-engineer Marcus Vitrivius Pollio (1st century BC) in his work “De Architectura”. In this work, Vitruvius mentioned about the existence of a powdery material used in construction of large buildings. “Caementum”, which means “binder” in Latin, has been translated into other languages as Cement (Eng.), Ciment (Fr.), Zement (Ger.), Cemento (Ita.). Inspired by the Italian word “Cemento” for phonetic similarity, the word “çimento” is used in Turkish [1].
Throughout human history, building materials has shaped the lifestyles of people, being a driving force behind the progress. And cement is one of the most important among them. In the construction industry of the modern world Cement plays a fundamental role in the history of humanity. It is considered an important turning point. Since the antiquity, humans have used a diverse range of binding agents for their building projects. However, cement has outperformed other binding agents and revolutionized the construction industry. Cement offers important advantages such as increased structural durability, holding building materials together, and increased water resistance.
Growth and development of civilizations throughout the history has closely been linked with basic building materials such as cement, in addition to natural factors such as population growth. As seen in Figure 1, cement production is also directly correlated with the population growth. As human societies have sprawled out and urbanized, the demand for residential and monumental structures have increased, which led to evolutions in the construction practices, and widespread adoption of cement as the basic material.
Figure 1. Change in Cement Production vs. World Population Growth [1,2]
The correlation between population growth and cement is clearly seen in development of modern cities and infrastructure. As urban populations grow and urbanization accelerates, so does the demand for construction materials, including cement, to meet the needs of growing communities. Versatility and durability of cement make it an ideal choice for a wide range of construction applications, from residential buildings and commercial complexes to bridges and roads. The use of cement-based materials has become widespread in modern construction practices, ensuring the structural stability, safety and sustainability of the built environments.
Cement, an important building material that shapes modern construction practices, has a rich and fascinating history dating back thousands of years. The story of cement begins in ancient times, with early civilizations such as the Romans, Egyptians, Greeks and Mesopotamians using materials such as lime and gypsum to bind stones and bricks together.
2. Binding Agents and Mortars in the History
In the early ages, the biggest problem of construction technology was the binding agent. In ancient times, craftsmen added organic substances such as blood, eggs, albumin, cheese, resin or inorganic substances such as terracotta (crushed and ground) to mortars and plasters to increase their durability. Some of these substances were used to ensure hardening, some to delay hardening and some to increase the strength after hardening. In some places, straw, plant fibers, animal hair and even human hair were used as binders in lime and plaster plasters to increase their durability. Sand, pozzolana, crushed stone, marble and brick particulates were used as fillers [4].
Concrete is thought to have been first used in huts found in the territory of former Yugoslavia, dating back to 5600 BC. Cherished as the most magnificent structures in the world, the Egyptian pyramids and the Great Wall of China, and many others, were built by different civilizations where it is known that various types of binders/mortars were used.
Marcus Vitruvius Pollio, a Roman architect and engineer who lived in the 1st century B.C., detailed the structures and related technologies of the past in his “Ten Books of Architecture”. Pollio recommended concrete for its ability to “polish the floor and create a strong foundation”. The book also mentions the use of pozzolana, a mixture of lime and crushed rock that is said to retain its hardness under water, to reinforce buildings. The mortars were prepared especially with lime, which took a long time to set. The use of pozzolana to prepare mortar was, followed by Romans, rediscovered by Europeans in the Middle Ages [5].
Throughout the history, different mortar materials have been used in construction.
Gypsum mortars
After the 18th century, gypsum mortars, which started to be used for decorative ornamentation, were prepared by mixing with lime, giving it binding properties. In the light of archaeological findings, it is thought that gypsum mortars was first used for the first time in Çatalhöyük in 9000 B.C. as a wall covering and ornamentation material mixed with lime. Around 7000 B.C., during the Sumerian and Assyrian periods, gypsum mortars were also used in urban buildings and roads.
The Egyptians built the pyramids 4,500 years ago using stone blocks ranging from about 2 to 45 tons and gypsum mortar. Gypsum mortar was used as a filler in the joints of the pyramids of Saqqara and Keops in ancient Egypt [6]. The stones of the Karnak Temple, built 3400 years ago by the Egyptian pharaoh Amenhotep II, were laid with anhydrite plaster. Anhydrite was also used in the Palace of Knossos built in Crete in the same years [7,8,9]. The function of gypsum mortar in these constructions was not to bind but to reduce friction while ensuring proper laying of the stone blocks [10].
Gypsum mortar was also used for plastering walls and wooden ceilings in ancient Greek and Roman civilizations, around 350- 400 B.C. In the same period in Egypt, impure calcinated gypsum was used instead of cement.
Lime mortars
Until the discovery of cement in ancient times, lime was the most basic binding material used in the construction of buildings. The raw material used to obtain lime is limestone. Limestone is known as the oldest material used as a binder. While pure limestone is produced by heating, lime mortar is created by adding and mixing water and sand.
There are interesting archaeological findings that prove that lime was used in the Neolithic to produce artificial stone, in a sense, concrete. Adding lime to the baked clay (brick) to produce metakaolin enabled structures with high-strength. 9000 years ago, flooring was made using a mixture of lime, puzzolanic soil, baked clay and sand and gravel. Excavations at Çayönü, Yiftah- El in Israel and Jericho in Jordan uncovered very high-strength (up to 35 MPa), shiny, well-compacted floor tiles, where lime was used as the construction material [10].
The Greeks obtained binding material by mixing lime and Thera (Santoren island) soil, which has clayey limestone properties [5]. Thanks to this mixture, a high strength binder insoluble in water could be obtained. A similar hydraulic binding property was produced by the Romans by adding Pozzuoli soil, found near the Vesuvius volcano, to the lime (see Pozzolana).
Pozzolana
About 2000 years ago, the Greeks and Romans ground lime and “puzolin” together, added sand to the resulting mortar and used the mixture as masonry mortar.
Thanks to Pozzolana, a special volcanic powder discovered in 150 BC, the Romans were managed to achieve underwater application. Pozzolana, together with aggregate, forms a very strong mortar.
The Romans’ use of volcanic ash, particularly pozzolana, in the production of cement was a very important innovation that significantly increased the strength and durability of their buildings. Pozzolana, a fine-grained volcanic ash found in regions such as Italy, was mixed with lime to create a hydraulic cement mixture that hardens once contacted with water.
The addition of pozzolana to the cement mix has provided many important benefits. These include:
1. Increased Strength
2. Improved Durability (resistance to moisture and corrosion)
3. Reducing Shrinkage and Cracking
4. Faster Hardening Time
The Romans used pozzolana-enriched cement in various iconic structures. The most known examples include;
Colosseum: The use of pozzolana in the construction of this huge amphitheater in Rome, built in the 1st century A.D., contributed to its longevity and durability.
Pantheon: Another famous Roman structure, the Pantheon, has a large concrete dome that showcases the use of pozzolana cement. The innovative design and durability of the dome is a testament to the mastery of Roman architecture, which made effective use of pozzolana.
Aqueducts and Bridges: The pozzolana-enriched cement was also used in the construction of Roman aqueducts and bridges, such as the Pont du Gard in France. These structures are a testament to the Romans’ mastery in the hydraulic engineering and materials technology.
Baths of Caracalla (Thermae Antoninianae): Built in Rome during the reign of Emperor Caracalla between 212-216 A.D., the baths are one of the largest and best preserved thermal complexes of ancient Rome. The use of pozzolana cement in the construction of the baths contributed to their durability and longevity.
Trajan’s Market (Mercati di Traiano): Built by Emperor Trajan in the early 2nd century A.D., this large complex served as a commercial center and administrative hub in ancient Rome. The inclusion of pozzolanized cement in the construction of Trajan’s Market helped to create a structurally sound building.
Theater of Marcellus (Theatrum Marcelli): Built by Julius Caesar and completed by Emperor Augustus, the Theater of Marcellus was the largest and most important theater in ancient Rome. The use of pozzolanic cement in the construction of the tiered seating and structures of the theater contributed to its architectural strength.
Appian Way (Via Appia): The Appian Way, one of the oldest and most important roads in Rome, was built using a combination of stone blocks and cement enriched with pozzolana. The use of pozzolana in road construction helped to strengthen the foundation and increase its durability.
Ponte Rotto (Broken Bridge): This ancient Roman bridge in Rome was built using cement enriched with pozzolana. The structure is a testament to the Romans’ mastery in the bridge engineering and material technology.
These examples highlight the widespread use of pozzolana in various types of construction in the Roman Empire. The addition of pozzolana cement not only increased the durability and longevity of these buildings and infrastructure, but also contributed to the architectural and engineering achievements of ancient Rome.
Khorasan mortar
This mortar, known as Khorasan mortar, is a material mixed with baked and ground earth products. In some applications, a mixture of lime, sand and gravel is also observed. Historical horasan mortars and plasters are obtained by using bricks as aggregate, tiles mixed with, as binders, lime and similar materials . These mortars and plasters are hydraulic due to the pozzolanic properties of brick shards and are also known as khorasan mortars and plasters. These mortars were called “Cocciopesto” [11] in Roman times, “Surkhi” [12] in India and “Homra” [13] in Arab countries.
The raw material of bricks, tiles and similar materials is a mixture of clay (kaolin, illite etc.), quartz and feldspar minerals. When this mixture is heated at 600 – 900 °C, the clays have different degrees of pozzolanicity depending on their temperature and mineralogical structure. At these temperatures, the structure of clay minerals deteriorates, forming amorphous alumina silicates. Thanks to this structure, calcinated clays have pozzolana properties (15).
Horasan mortars and plasters harden by the reaction of amorphous silicates and aluminates in the mixture with water and the carbonation of lime with the carbon dioxide in the air. As a result of hydraulic reactions, calcium silicate hydrate and calcium aluminate hydrates are formed, increasing the strength of mortar and plaster, which also enables it to harden under water. Thanks to their hydraulic properties, these mortars and plasters were used in Byzantine, Roman, Seljuk and Ottoman cisterns, water wells, aqueducts and bath structures (14).
Vitrivius writes that by adding baked brick shards and dust into the pozzolized lime binder, much better quality and low abrasion floors were obtained [5]. Khorasan Mortar was also used in the Giza pyramids and Assyrian buildings. The presence of this building material is also observed in buildings constructed in unrelated regions and at different ages. For example, Khorasan mortar was found on the island of Bali in southern Java, around the Indus River in India (under the name Surkhi), and in the El- Tajin pyramid in Mexico [14].
3. Iconic Structures and Mortars in Ottoman Architecture
The constant use of different mortars by the Greeks and Romans in their buildings also influenced Seljuk and Ottoman architecture. The Ottomans, Seljuks and Byzantines also used horasan mortar in their buildings.
One of the most important elements contributing to the success of the constructions of Mimar Sinan, the famous chief architect of the Ottoman Empire, was the use of pozzolana, a volcanic ash-based material with remarkable binding properties, in his construction projects.
Pozzolana played a pivotal role in enhancing the structural integrity and longevity of Sinan’s buildings and provided important benefits that distinguished his buildings from other structures. Mimar Sinan used building materials such as pozzolana and Khorasan Mortar in his iconic works to increase strength and durability, and aimed to reduce shrinkage to minimize the risk of cracking and deformation.
As pozzolana accelerates the setting time of cement-based mixtures, allowing construction to proceed faster, Sinan used pozzolana efficiently in his buildings. In addition, Sinan’s innovative use of pozzolana helped protect his buildings from water damage, ensuring protection of them for a very long time. Valuing the architectural flexibility, Mimar Sinan created flexibility in his designs and constructions with use of pozzolana.
Notable examples of Mimar Sinan’s buildings where the use of pozzolana is evident include:
Considered one of Sinan’s greatest achievements, the Selimiye Mosque in Edirne features a monumental dome and intricate minarets built using pozzolana-based materials. The use of pozzolana in the construction of the mosque contributed to its structural stability and timeless beauty.
The Şehzade Mosque is another of Sinan’s masterpieces, showcasing the architect’s masterful integration of pozzolana in the construction of the dome and elaborate facade. The use of pozzolana in this mosque is an example of Sinan’s innovative approach to building design.
The Süleymaniye Mosque, one of Sinan’s most famous works, is a good example of the effective use of pozzolana in creating large domes, massive columns and intricate ornamentation. The inclusion of pozzolana in the construction of the mosque enhanced its structural integrity and architectural splendor.
Mimar Sinan’s effective use of pozzolana not only increased the quality and durability of his buildings, but also left a lasting legacy in the history of Ottoman architecture. By harnessing the benefits of pozzolana, Sinan was able to create monumental structures that continue to inspire admiration and awe, showcasing his mastery of construction techniques and innovative approach to architecture.
4. Renaissance Period
The Renaissance ushered in a new era in which people were encouraged to think differently and opened the doors to the industrial revolution. Britain’s naval fleet of merchant and colonial ships needed new lighthouses in the 18th century, which then became an important driver for the cement industry. The Eddystone Cliff near the Port of Plymouth, England, has long posed a threat to ships entering and leaving the harbor. The construction of the 37-meter-high Eddystone Lighthouse, built using mortars that harden underwater for the convenience of mariners, was completed between 1757 and 1759.
Historically gypsum, lime and puzzolan were used, and today concrete-like materials have been used frequently with the innovative period. The aim here was to obtain binders with high hydraulic properties. The most obvious example of this is Roman cement.
One of the earliest known patents on this subject belongs to James Parker and is dated 1796. Roman cement is also known as “black cement” because of its color (due to its puzzolan color) and “water cement” because of its hydraulic properties.
The patented Atkens or Atkinson cement used in England in the same period is a derivative of Roman cement. According to the first known recipes, Roman cement was produced by baking and grinding clayey limestone (Lt. septaria) from the Isle of Sheppey in England. Besides the UK, this cement was used in Central Europe in France, Northern Italy near Bergamo and near Salzburg and Vienna in the Tyrol Region, Switzerland, Southern Germany, Bohemia and Galicia in Southern Poland, and Russia. It is widely accepted that cement as a binder can hold up to twice the weight of aggregate [16].
In 1756, British engineer John Smeaton found that the best cement was obtained from soft limestone containing a certain amount of clay. About 40 years later, James Parker produced cement in England using limestone with high impurity content. Cement production from clay and limestone was initiated in France by Louis Vicat in 1813 and in England by James Frost in 1822.
Roman concrete (opus caementicium) consisted of a mixture of aggregate (sand, gravel, crushed stone), binding material and water. Gravel, large stones, rubble and brick fragments were used as aggregate. Lime or gypsum was used as a binder and mixed with rubble stones to form a strong mortar (lime mortar). A binding material was obtained by the Romans by adding Pozzolana, a special volcanic powder found near Baiae in central Italy and around the cities at the foot of Mount Vesuvius [16].
Binders with high hydraulic properties, known as ‘Roman cement’, were frequently used in building facades in the context of Art Nouveau architectural styles in the 19th century and the first quarter of the 20th century. It found widespread application especially during the Austro-Hungarian Empire, with Vienna as its center. It was also used in other Central European countries, Russia and England. Although not with the same intensity, there are also examples in our country, especially in Istanbul. [16]
References
1. Urhan, S., “Temel yapı malzemesi çimentonun öyküsü”, Metalurji, 24 (124): 32-45 (2000). 2. Robbie M. Andrew, Global CO2 emissions from cement production, 1928–2018, Articles Volume 11, issue 4 ESSD, 11, 1675–1710, 2019 3. https://www.uztarih.com/2018/07/gecmisten-gelecege-dunya-nufusu.html 4. Rabia Aktaş https://www.arkeo-tr.com/antik-donemde-kullanilan-harc-turleri.html 5. Vitrivius, A., Mimarlık Üzerine On Kitap, Kitap 2, ss.25-45, Kitap 7, ss.143-154, Morgan, M.H. ter- cümesinden Türkçe’ye tercüme: Güven S., Şevki Vanlı Mimarlık Vakfı Yayını, 1990. ISBN 975-772- 2-03-0. 6. Finch J.K., 1954, The Story of Engineering, Anchor Publ., New York. 7. Kinder, H., Hilgemann W., 1964, D.T.V. Atlas zur Weltgeschichte, Deutscher Taschenbuch Verlag GmbH, München. 8. Straub H., 1964, History of Civil Engineering, MIT Press, Cambridge MA. 9. Grün R., 1951, İnşaat Mühendisleri ve Mimarlar için Kimya, Serdaroğlu N. tercümesi, İTÜ 279 No. Yayın, Istanbul. 10. S. Akman, 2003, Yapı Malzemelerinin Tarihsel Gelişimi Türkiye Mühendislik Haberleri Sayı 426 -2003/4 11. Massazza F., Pezzuoli M. (1981) Some Teachings of a Roman Concrete Mortars, Cement and Grouts Used in the Conservation of Historic Buildings, Proceedings of Symposium in Rome, s. 219-245. 12. Spence R. (1974) Lime and Surkhi Manufacture in India, Appropriate Techonology, 1 (4), s. 6-8. 13. Lea F.M. (1940) Investigations on Pozzolanas, Building Research, Technical Paper No.27, s. 1-63. 14.https://tr.wikipedia.org/wiki/Horasan_harcı#:~:text=Bu%20harç%20ve%20sıvalar%20tuğla,Lea%2C%201940)%20olarak%20adlandırılmıştır. 15. He C., Bjarne O., Emil M. (1995) Pozzolanic reactions of six principal clay minerals: Activation, Reactivity Assessments and Technological Effects, Cement and Concrete Research, 28/8, s.1691-1702 16. N. Baturayoğlu Yöney, , ‘Roma Çimentosu’ Tarihçesi, Özellikleri ve Onarımı
Photos
https://t24.com.tr/haber/roma-daki-kolezyum-un-yeralti-tunelleri-ilk-kez-ziyarete-aciliyor,962425
https://www.travelandleisure.com/rome-pantheon-admission-price-7368425 https://tr.m.wikipedia.org/wiki/Dosya:Pont_du_Gard_BLS.jpg https://en.wikipedia.org/wiki/Baths_of_Caracalla
https://www.getyourguide.com/trajan-s-market-l4790/yunan-mitolojisinin-dunyasi-tc2040/?visitor-id=KLN04X7NYE1AT8J1B18T5K94ZQAXIIEN&locale_autoredirect_ optout=true
https://www.italia.it/en/lazio/rome/teatro-marcello https://x.com/dusunbildergisi/status/1672699617597587456 https://en.wikipedia.org/wiki/Pons_Aemilius https://www.yasemin.com/yasam/haber/2978205-selimiye-camii-nerede-selimiye-camii-hangi-ilcede-selimiye-camiinin-onemi
https://kulturenvanteri.com/tr/yer/sehzade-mehmet-camii/#17.1/41.013821/28.957209 https://tr.wikipedia.org/wiki/S%C3%BCleymaniye_Camii
