The precast building in the air vent is a main line of carbon reduction that few people pay attention to“
According to Alpha survey, migrant workers’ labor force is characterized by shortage and aging.
It is not difficult to understand the meaning of precast buildings, which refers to transferring a large number of on-site operations in traditional construction methods to factories.
This kind of dwelling place, which originated from natural caves and was cut by simple tools, became the earliest architectural form of human beings.
In the following years, after the transition of animal bone tents and animal skin tents, from the Paleolithic Age to the Neolithic Age.
Building is an indispensable part of the history of human development.
The purpose of this paper is to discuss with readers the differences and advantages between precast architecture and traditional architecture.
It can be said that precast buildings are the only way for traditional buildings to transform into green buildings, and a crucial link to achieve the goal of dual carbon.
With the advent of the industrial revolution, modern buildings with reinforced concrete as the main material began to appear, and their representative works were skyscrapers towering into the clouds.
The only way to transform traditional buildings into green buildings may be that some readers are unfamiliar with precast buildings.
However, it is easier to form a set of standardized system with industrialized materials and cast construction methods to ensure the quality.
Take the wall as an example.
As we all know, the construction industry, as an important pillar industry of China’s national economy, has grown with China’s huge economic growth.
On the other hand, the precast construction site mainly adopts dry operation, which can effectively reduce energy consumption and environmental pollution; In addition, the precast buildings can also be reused due to their characteristics of demolition; According to the estimation of senior experts in the industry, the carbon emissions of various precast buildings in the construction phase can be reduced by about 20% compared with cast-in-place buildings; In the whole life cycle, carbon emissions can be reduced by nearly 40% due to the use of new materials.
The core elements are prefabrication and modular assembly.
Compared with traditional buildings, the core advantage of precast buildings is to reduce pollution and emissions.
Most components of the precast building are completed in the factory.
With stone, wood, mud brick and straw as raw materials, houses with real architectural elements have emerged.
Then superimpose the urban reconstruction of World War II, so that precast buildings are rapidly popularized.
The precast building is the only way for traditional buildings to transform into green buildings.
In the agricultural era, human beings began to settle down.
According to the data of China Building Energy Consumption Research Report (2020) issued by the Energy Consumption Special Committee of China Building Energy Conservation Association.
The construction phase has relatively less carbon emissions, accounting for 1% of the national carbon emissions.
Building components and accessories (such as floor slabs, wallboards, stairs, balconies, etc.) processed and cast in the factory, transported to the construction site, and assembled and installed on site through reliable connection.
The construction migrant workers are more scarce, making the human cost higher than the overall level.
This is the inevitable result of the development of Internet plus service industry.
The carbon emission in the construction operation stage is 21.1tCO2, accounting for 21.9% of the national carbon emission.
In 2018, the maximum carbon emission in the production stage of building materials in China was 2.72 billion tCO2, accounting for 28.3% of the national total.
The same is true in the construction operation phase.
Stone components are chiseled at the processing site, or wood columns, beams, brackets and other components are cast, and then transported to the site for installation.
For example, pillar buildings with stone structures in ancient Egypt and Greece, Gothic churches built with stone and stained glass in the Middle Ages, and wooden temples and palaces in China.
However, the production of steel, cement, aluminum and other building materials is accompanied by high emissions and high pollution.
With the gradual reduction of labor force, the labor cost continues to rise.
Since 2014, the number of migrant workers in the construction industry has decreased almost every year, and the supply side of migrant workers has declined year by year.
According to statistics, the average income of migrant workers has maintained an annual growth rate of more than 5% in the past five years.
In fact, precast buildings have a long history.
The water and electricity installation and the main body installation can be carried out simultaneously.
The proportion of precast buildings in the United States, Japan, Europe and other developed countries has reached more than 80%, while domestic precast buildings are just starting.
About 90% of them come from the production stage of steel, cement and aluminum.
Building materials and processes have undergone many iterations and upgrades, giving birth to a new form of architecture – precast architecture.
In ancient times, large buildings such as temples, palaces and tombs were built with many assembly concepts.
Today, scientific and technological progress has driven the rapid development of modern building technology.
With the sustained economic development, the human cost has risen.
For precast buildings, the walls are precast as a whole, and then spliced on site, just like a building block game played by children.
With the continuous innovation of the Internet business model, many new jobs have been created, and the ability of the service industry to absorb employment has exceeded that of traditional industries.
Traditional buildings require workers to lay bricks layer by layer on the site.
Young migrant workers flow into express delivery, takeout, we media, online car hailing and other industries..
At the same time, the age structure has gradually increased, and the number of migrant workers aged 18 to 40 has declined significantly.
The waste of traditional building materials is serious, and the construction process is accompanied by dust, noise, construction waste, etc.
Compared with traditional buildings, precast buildings have incomparable advantages in building quality, construction period, energy conservation and environmental protection.
The overall delivery is 30%~50% faster than that of the traditional building.
To be specific, the traditional construction method is highly dependent on manual work, and the quality monitoring is difficult.
Since the Paleolithic Age, humans have had the concept of cave dwelling.
The traditional construction industry is a labor-intensive industry, which is highly dependent on labor.
Since the 18th century, with the rapid population growth brought by the development of the industrial revolution, the demand for housing and factory buildings has risen rapidly.
From another dimension, the decline of the demographic dividend may force the transformation and upgrading of the industry.