The recycling rate of construction waste is as high as 97%
The "secrets" in the underground of Universal Studios Beijing
Our reporter Zhao Ang, correspondent Huang Yiyi
Looking at the "Hogwarts Castle" in Universal Studios Beijing today, the builders of Beijing Construction Engineering Resources Corporation still remember what the land looked like six years ago-overgrown with weeds and thorns.
In 2015, Beijing Universal Studios started the construction of basic projects. However, after demolition and other disposals, the soil structure is loose, and a huge amount of domestic waste and construction waste are buried underground. A theme park with an area of 4 kilometers will generate 4 million. Tons of miscellaneous fill, if stacked at a height of 10 meters, can fill 37 standard football fields.
Where to move the "misfill"
The soil mixed with construction waste and domestic waste with complex composition is called "miscellaneous fill". If construction is directly on the miscellaneous fill, a series of hidden dangers such as subsidence, cracking and dumping will occur.
According to the traditional disposal method, all these miscellaneous fills have to be transported away and placed in a place or landfilled.
But where can the 4 million tons of miscellaneous fill be piled and filled, and how to find enough plain soil for backfilling?
This problem cannot be solved. The castles and roller coasters on the ground can only be "castles in the sky".
In this regard, the builders proposed an unprecedented plan: the construction waste can be recycled and reused.
However, it is conceivable that Universal Studios has such a huge amount of work.
To this end, the technicians have conducted a solid preliminary investigation, picking up, sorting, weighing, recording, and analyzing in countless dirty and messy engineering waste dumps, and finally formed a large database of construction waste components, thus boldly Universal Studios has tailored a set of special plans-in-situ disposal, so that the miscellaneous fill does not need to be transported, and a disposal production line is built on site to eat the miscellaneous fill mixed with construction waste and solid waste. "Go in" and "spit out" are high-quality recycled aggregates and high-quality reduced soil, which are then directly used for earth backfilling in the site.
Starting from the "experimental field"
Although this plan has received preliminary approval, there is no precedent in China, so they first established a "experimental field" on the north side of Universal Studios.
The team established 6 soil pits for comparative experiments.
The final test data shows that the land filled with reduced soil and recycled aggregate has the strongest pressure bearing capacity, and at the same time, all indicators are better than natural plain soil, which fully meets the high-standard construction requirements of Universal Studios.
The success of the plan not only saves the owners hundreds of millions of dollars in capital investment and several months of construction period, it is also of great significance to the construction of an ecological city.
And behind this, there is an unknown pay.
When entering the site, temporary water, electricity, and material transportation all need to be deployed by multiple parties; there is no road, and the staff rushed out of the road with their feet forcibly to select sites and sample; squatted on the ground at noon, just whirring The north wind eats a boxed lunch.
When the schedule was tightest, everyone lived in the container on site.
At the busiest hour, there are about 2,000 muck trucks going back and forth every day.
Independent research and development equipment
The key to turning miscellaneous fills from waste into treasure in situ is equipment and technology.
The technical team should independently research and develop the equipment, and then design the production line according to the demand.
They started from the northeast and went all the way to the south, looking for every piece of equipment needed on the production line, and constantly debugging every part.
"The plan is being changed almost every day, and there is no existing experience in the country to learn from." Wang Xiaopeng, a process designer at the time, said, "The size of the sieve and the shape and thickness of the sieve have to be adjusted over and over again."
Universal Studios has a huge amount of miscellaneous fill and a short construction period. The foreign party once lost confidence, questioned China's technology, and wanted to give up.
The builders were not convinced, "We must fight for the Chinese people!"
In the end, the builders tailored for the Universal Studios project and designed the most cutting-edge technological process, including 8 sets of pretreatment systems and 1 set of construction waste disposal systems, which together form the "core processor" of the production line.
At the same time, their independent research and development of a variety of core equipment such as vibrating wind separators and hammer crushers can increase the recycling rate of construction waste to more than 95% and have obtained a number of national patents.
After two years of pioneering earth-filling projects, the builders have created a miracle: a total of 2.7 million cubic meters of miscellaneous fill has been disposed of, and the resource utilization rate of construction waste is as high as 97%, which is equivalent to saving more than 400 acres with a buried depth of 10 meters. Soil resources.