by ▲ click attention | join the world of concrete together.
In recent years, with the development process of building industrialization and building industrialization becoming more and more hot, concrete prefabricated parts and prefabricated buildings have attracted more and more attention.
This seemingly new industry has attracted a lot of enterprise capital and resource investment in order to take the lead in future development.
Germany is a pioneer of modern construction industrialization and has a perfect PC assembled construction industry chain.
Therefore, Chinese enterprises have strengthened cooperation and exchanges with German enterprises and want to introduce the complete industrial chain model into China.
Through the research and study of international advanced countries, this article hopes to give some thoughts and Enlightenment to domestic practitioners in the field of PC prefabricated architecture at this stage.
What are PC components? “PC is precastconcrete (precast concrete) In the field of housing industrialization, it is called PC component.
English: precastconcrete, also known as PC component, refers to the concrete products processed and produced in the factory through standardized and mechanized methods.
The cast-in-situ concrete shall meet the needs of the construction site and the cast-in-situ concrete.
Precast concrete units are widely used in construction, transportation, water conservancy and other fields, and play an important role in the national economy.
Compared with the cast-in-situ concrete, the concrete prefabricated parts produced in the factory have the following advantages: for construction workers, the relatively stable working environment in the factory has a higher safety factor than the complex site operation; The quality and technology of building components can be better controlled through mechanized production; The standardization of dimensions and characteristics of prefabricated parts can significantly speed up the installation speed and construction progress; Compared with the traditional on-site mold making, the mold in the factory can be reused and recycled, and the comprehensive cost is lower; Mechanized production requires less labor.
With the continuous increase of labor cost, the cost advantage of prefabricated parts produced on a large scale will become more and more obvious.
Environment: the on-site operation volume of the construction site with prefabricated parts is significantly reduced, and the dust pollution and noise pollution are significantly reduced.
The history of concrete prefabrication concrete prefabrication originated in Germany.
The development history of concrete prefabrication in Germany is closely related to the development of concrete materials, the demand of prefabrication buildings and the aesthetic concept of concrete materials.
The development of concrete materials Joseph asperdine, British, Mason.
On October 21, 1824, he obtained the British patent certificate of “Portland cement” No.
5022 in Leeds, and thus became the immortal inventor of cement.
However, the stability of the cement invented by him could not be guaranteed.
Until 1844, he made essential improvement for the British Isaac Charles Johnson and laid the foundation for today’s invention of Portland cement.
One year later, in 1845, Germany produced artificial stone stairs, that is, the first concrete precast unit in Germany, which opened the history of concrete precast units in Germany.
The following is a way to illustrate the history of concrete precast units in Germany in the form of memorabilia: ▲ PC prefabricated building development ★ in 1845, Germany produced artificial stone stairs, that is, the first concrete precast unit in Germany ★ in 1849, French gardener en: Joseph Monier (English) invented reinforced concrete in 1849 and obtained a patent including reinforced concrete flowerpots and reinforced concrete beams and columns followed by highway guardrails in 1867.
From 1850 to 1870, with the first batch of Portland cement manufactured in Germany in 1850, it was widely used in the manufacture of cement pipes in the next 20 years.
★ in 1870, with the determination of the formula of flowing mortar, the decorative lines, columns, railings and other decorative components of the house facade were produced in large quantities; The precast concrete tiles on the roof were also produced in large quantities.
In 1878, the state of Prussia issued the specification for Portland cement.
In 1890, the German engineer c.f.w.
doehring applied for a patent for his invention of prestressed concrete.
In 1903, the German Hamburg construction company Juergen Hinrich magens built the world’s first commercial concrete mixing plant, It is the first time to apply for a patent for transportable “commercial concrete”.
★ in 1907, the dome of the Berlin national library was built with precast concrete ★ in 1912, John E Cozelmann applied for a patent for prefabricating all the components of a multi-storey building with reinforced concrete.
★ in 1929, the first reinforced concrete road was built.
★ in 1930, concrete with retarding requirements was developed for underground engineering ★ around 1940, concrete precast units were also widely used in places needed by military industry.
★ in 1948, the first prestressed concrete bridge was built in West Germany.
★ in 1954, the invention of a new commercial mixer truck replaced the old means of transportation, and 50% of the country’s cement output was consumed by commercial mixing stations.
★ in the 1950s and 1960s, a large number of multi-storey prefabricated slab residential buildings were built in East Germany and West Germany industrial zone after the war.
★ in the late 1960s, filigran company of Germany invented the reinforced truss and also the reinforced truss composite floor slab ★ in 1978, steel fiber reinforced concrete was widely used.
★ in the mid-1980s, the German filigran company invented the prefabricated reinforced truss laminated wallboard ★ in the 1990s, the assembly line equipment of plate prefabricated components has been greatly developed, and the demand for prefabricated buildings has promoted the development of concrete precast units in three aspects in this field ★ prefabricated houses ★ with the invention of double-sided laminated wallboard in the 1980s, The basement of many houses are built with laminated plate system, which speeds up the construction speed..
