Chapter 453: Solving the Mystery (1/2)

After ten seconds, the modeling was complete.

Just as the police were wondering what the next step was, these messy concrete fragment models flew on the big screen.

”Model calculation... 5%... 55%... 100%...”

As the progress bar moved quickly, these broken models were magically combined one by one. It was like a digital wall, which was broken and restored. When the progress bar had reached one hundred, the original messy and broken virtual model had become a square, a virtual concrete wall covered with cracks. The whole process took less than a minute.

The policemen's eyes widened again because the recombined virtual wall could clearly show there was an irregular deep hole the size of a potato chip bucket in the center.

There were many defects around the deep hole that were broken into particles and could be unrestored. But this did not prevent people from intuitively judging this was a circular deep hole with cracks in the concrete that have spread from around the deep hole in the form of a net. It was like a car glass, the kind of crack shattered by a bullet.

”Hiss…”

The policemen took a breath. Could it be said that this wall was broken by armor-piercing bullets?

How loud was that, and how bold?

”If it is hit by a high-speed object, the passage created by the gangster on the wall should be circular. But the passage left on the scene is obviously square.” A police officer in the trace inspection room said in a low voice: ”Moreover we also did not detect any traces of gunpowder on the concrete fragments.”

”It's not the impact of a high-speed object.” Ye Qing carefully looked at the restored three-dimensional simulation map and explained: ”If I guessed right, this should be the principle of static blasting. It is not the kind of blasting that everyone knew, it is the use of mechanical energy to explode hard objects, rocks and concrete have extremely high external compressive strength, but the internal outward tensile strength is poor. If the external compressive strength is 100, the internal strength is only 2 to 10. A hydraulic splitting machine, I don't know if you have seen it before?”

”For mining stone, you only need drilling a few small holes, put the splitter into the hole, and in two minutes you can collapse a piece of hundreds of tons of granite into two pieces from the inside.”

”There is such a thing?” Zhang Zhitong was completely eye-opening today: ”Then you mean, this concrete wall was damaged by a hydraulic splitter?”

”The principle is similar, but it's not a hydraulic splitter.”

Ye Qing pulled out a drawing-paper and said as he drew: ”After you restore the fragments, you collected from the site, and there must be some defects in the surrounding area that turned into dust particles. There should be four to eight small holes drilled around the concrete. It's just the diameter of these small holes is too small, and maybe as thick as a pencil. After blasting, the traces are covered. They should have used a more advanced hydrostatic blasting machine. The big round hole in the center is used to place the blasting machine. Then a few small holes are punched around to keep the concrete cracking in the small holes but in the scope of construction.”

Every time Ye Qing was saying a piece of information, and the eyes of these policemen became brighter.

”Then...Is this equipment loud?” Zhang Zhitong asked with a little excitedly.