Neolithic age, about 4000- 10000 years ago: clay was used, and pillars, floors and walls made of natural ginger stone were also found.
Around 2000-3000 BC, China, Egypt, Greece and Rome began to use gypsum or lime obtained by calcination to prepare masonry mortar.
At the beginning of AD, lime-pozzolan, concrete and other lime-pozzolan materials.
/kloc-in the second half of the 0/8th century, hydraulic lime and Roman cement appeared successively, which can be regarded as the embryonic form of modern portland cement manufacturing.
1early 9th century (18 10- 1825), Portland cement (Portland cement, which is called Portland cement in China).
British asp Ding (J. A. spdin) first obtained the patent right of this product at 1824.
At the beginning of the 20th century, various portland cements developed gradually, such as quick-hardening cement, sulfate-resistant cement, low-heat cement and oil well cement.
As can be seen from the above, the development of cementitious materials has gone through various stages: natural cementitious materials (such as clay)-gypsum, lime-lime-pozzolana-hydraulic lime, natural cement-portland cement-different types of cement.
inorganic cementing material
In building materials, it refers to any substance that can change from paddle to hard solid through a series of physical and chemical actions or after being mixed with other substances (such as water), and can bond bulk materials (such as sand, stone, etc.). ) or blocky or flaky materials (such as bricks and stones). ) into a whole is called a cementitious material.
Cementing materials can be divided into organic cementing materials (such as asphalt, resin, etc.). ) and inorganic cementing materials (such as lime, cement, etc. ) according to their chemical composition.
Inorganic cementitious materials, also known as mineral cementitious materials, can be divided into pneumatic cementitious materials and hydraulic cementitious materials according to hardening conditions.
Air-hardened cementitious materials can only be hardened in air, and their strength can only be maintained or developed in air, such as gypsum and lime. Hydraulic cementing materials, such as cement, can be hardened not only in air, but also in water to maintain and develop their strength.
China has a long history of using inorganic cementitious materials.
As early as the Zhou Dynasty, lime was used to build imperial tombs.
From the Zhou Dynasty to the Southern and Northern Dynasties, people used a mixture of lime, loess and fine sand as plaster for rammed earth walls or adobe walls, or as floors for rooms and graves.
During the Ming and Qing Dynasties, the use and development of concrete made lime more widely used.
Today, lime still occupies a certain position in China's architecture.
In addition, in ancient buildings in China, lime and some organic materials were often used to make composite cementitious materials, and good results were obtained.
According to historical records, in the sixth year of the Southern Song Dynasty (1 170), the mixture of glutinous rice juice and lime was used as the cementing material in the construction of He Zhong. An important part of the masonry wall of Nanjing City built in Ming Dynasty is to use lime and glutinous rice juice as grouting materials.
In the book "Heavenly Creations" in the Ming Dynasty, there are more detailed records about glutinous rice juice-lime.
In addition, in ancient buildings, blood materials-lime, tung oil-lime is often used as putty.