When concrete and cement mixers come to mind, one thinks of sidewalks, construction sites and urban settlements. It is often forgotten that many historical and monumental buildings of the past were created with skilled craftsmanship and concrete. Society today often forgets just how advanced ancient civilisation was.
Accuracy, skill, and intelligence were needed to have discovered the exact method for creating concrete, as well as being able to mould it to create the structures that still stand today. Read this article to learn a little more about how cement mixers in an ancient form were most likely used to assist the long and detailed building process of creating such timeless structures.
Cement Mixers: A City Cast In Concrete
The Romans are famous for having used concrete and cement to create almost the entire ancient city of Rome. Two of the most famous ancient Roman concrete structures known today are the Pantheon and the Colosseum. Some other noteworthy Roman concrete structures include the following:
• Amphitheatre, Nimes
• Aqueduct of Segovia
• Library of Celsus
• Maison Carree
The Pantheon, not to be confused with Parthenon, is a former Roman temple and a current Catholic church called Basilica di Santa Maria ad Martyres or Basilica of St. Mary and the Martyrs. The exact age of the Pantheon is unknown, although historians estimate the structure came about between 27 BC and 14 AD.
It was built on the site of an earlier temple that was commissioned by Agrippa during the reign of Augustus. After the fall of Ancient Rome, the Pantheon was rebuilt due to it being burnt in a fire. Emperor Hadrian repaired it in 126 AD and instead of it being inscribed with its date of construction, it retained the inscription of Agrippa’s older temple which burnt down.
The Pantheon is the best preserved Ancient Roman monument. Its survival is a miracle, considering Ancient Rome’s downfall and the destruction of most Roman monuments. The survival of the Pantheon through these historic, barbaric raids remains a mystery. The structure of the building is considered to be way ahead of its time and the exact composition of the concrete material used to build it remains unknown. The concrete does, however, appear to be somewhat similar to modern-day concrete.
The Pantheon is an architectural miracle. It is well-known due to it being one of the best-preserved structures of all Ancient Roman buildings. It has also been continuously used throughout history and since the 7th century, it has been a church dedicated to St. Mary and the Martyrs.
The Pantheon’s dome is the world’s largest reinforced concrete dome. Despite being built over 2000 years ago, the breathtaking structure still stands today, indicating just how powerful Ancient Roman concrete is. The spectacular design displays elegance, and harmony and is proportioned perfectly, keeping locals and visitors in awe of its beauty and magnificence today.
The Pantheon’s Dome and Columns
The most interesting part of the Pantheon is its giant dome that has a famous hole at the top known as the eye of the Pantheon, or oculus. The dome was the largest in the world for 1300 years and remains the largest unsupported dome in the world. The dome’s diameter is 43,30 metres (142 ft) wide and is perfectly proportioned to suit the Pantheon as the distance from the floor to the top of the dome is exactly equal to its diameter of 43,30 metres.
The hole of the oculus or eye of the Pantheon is 7,8 metres in diameter and is the only source of light in the building. It is believed that the oculus is the connection between the temple and the gods above. Rain occasionally does fall through the eye of the Pantheon; however, the floor is slanted, allowing for the water to drain as it hits the floor. Rain seldom falls inside the dome.
A lighting effect can be viewed on the 21st of April at midday when the sun strikes a metal grille above the doorway. It is on this day that the sun’s light floods into the courtyard, creating an impressive sight. The Romans celebrated April 21st as the founding day of the city and possibly thought that their Emperor was raised to the level of their gods as he stood in the lit-up courtyard.
16 massive Corinthian columns are used to support the portico, weighing around 60 tons each. Each column is 11,8 metres (39 feet) tall and 1,5 metres long in diameter. They were brought all the way from Egypt during ancient times and were dragged more than 100km from the quarry to the Nile River on wooden sledges.
The columns were floated by barge down the Nile when the water level was high during spring floods and then transferred to vessels that crossed the Mediterranean Sea to reach the Roman port of Ostia. The columns were then transferred back onto barges and pulled up the Tiber River to Rome.
The columns support a triangle pediment that has an inscription attributing the Pantheon to Marcus Agrippa. This triangle pediment is the only original piece of the Pantheon remaining which was built by Agrippa. Hadrian most likely left it as a gesture of respect to the original builder when he rebuilt the Pantheon.
The Pantheon Today
The Pantheon now contains the tombs of the famous artist, Raphael, and of several Italian Kings and poets. Its marble floor is the original ancient Roman flooring which was installed while building the structure and it features a design of geometric patterns. In front of the Pantheon is a beautiful water fountain called the Fountain of the Pantheon. It was originally made of marble and designed by the famous architect Giacomo Della Porta in 1575. Later in 1711, Pope Clement XI requested that the fountain be modified and have Filippo Barginoni design a new layout. It now has a basin made of stone and features the obelisk of Ramses II in the centre of the plinth with four dolphins decorating the base.
The Colosseum is the world’s largest amphitheatre and is located in Rome, Italy. It was built during the reign of the Flavian emperors as a gift to the Roman people, hence why it is also called the Flavian Amphitheatre. When the amphitheatre first opened, emperor Titus celebrated with a hundred days of gladiatorial games. Aside from the games, the Colosseum was also used to host dramas, re-enactments, and public executions.
Gladiator games, also called “munera”, were mainly organised by private individuals rather than the state. The “munera” games were battles between two men and the other games, called “venationes”, were the most popular and consisted of men fighting against animals. The fights were usually single-combat and lasted for an exhausting 10- 15 minutes.
The gladiator fights became a propagandist tool, demonstrating the might of the Roman Empire and showing the city’s population that their Emperor personally cared for their well-being.
The Building Structure
Towering four stories high, holding enough restrooms to accommodate a packed house, and providing 110 drinking fountains, the famous structure can hold more than 80, 000 spectators at its maximum capacity. The ground floor has 80 different entrances and the seating is divided into five areas, according to social class. The complex design features a retractable roof and on hot days, an awning called a velarium was unfurled above the upper deck to shade the spectators from the sun.
The egg-shaped structure has a short axis of 156m and a long axis of 188m. It is 50 metres high, 190 metres long and 156 metres wide. The extraordinary structure was built by Titus Vespasian and was made from travertine limestone, tuff (volcanic rock), and brick-faced concrete and was held together using 272 metric tons of iron clamps.
It was built around 70- 80 AD when concrete was recently discovered, and concrete mixers were most likely used in an ancient or simple form. The builders were unsure of the concrete lifespan and so combined the Roman concrete with stone to build the arches of the Colosseum to increase its strength.
A strong foundation was needed to handle the enormous weight of the building. The Colosseum is built on a marshy site of an artificial lake, requiring the builders to drain all the water from the lake and excavate a 6 metre trench using their own hands. Concrete was used to lay the foundations, construct the walls, and used as a filler between the inner and outer walls. Drains were built to keep the arena dry.
It is estimated that around 900, 000 metric tons of concrete, brick, travertine, limestone, and volcanic stone were used to build the Colosseum. It is likely that ancient concrete mixers were used to create the strong Roman concrete that keeps the amphitheatre standing today. Two-thirds of the Colosseum have been destroyed due to vandalism, earthquakes, and fires; however, the building is still appreciated and considered a symbol of the invincible Roman Empire.
Roman concrete, also known as opus caementicium, is an ancient form of concrete made from hydraulic setting cement. It was made using aggregate from ceramic tile, brick, rubble, or pieces of rock, and then combined with gypsum, quicklime and volcanic dust, known as pozzolana.
This formed a super strong concrete that was known to harden over time and withstand being submerged in saltwater for years. The pozzolanic ash prevented cracks from spreading, unlike modern concrete. This concrete would harden to be even stronger by benefitting from a reaction to seawater which crystallised the concrete into tobermorite, becoming resistant to fracturing. The resultant concrete formed “the most durable building material in human history”, allowing for ancient Roman structures to stand the test of time.
Concrete and BS Suppliers:
We at BS Power offer accessible, affordable, and high-quality building equipment suited to any construction project. We currently have three different kinds of cement mixers available to you. Each cement mixer has a Baumax RX200 2:1 6.5HP engine and the drum volumes are 360L, 400L and 500L.
Our cement mixers are ideally suited to contractors and rental companies; however, anyone can buy one from us. Our cement mixers each have a ring gear cover and an enclosed engine cabin to ensure operator safety. The drum thickness is 3mm and the chassis is constructed from channelled iron and folded metal.
Check out the cement mixers guide on our website to find the machinery best suited to you!