In recent days, teachers and students from the School of Civil Engineering of Shaoxing University of Arts and Sciences have been rushing to the construction site of water conservancy projects in the west. Different from the past, there is no large survey equipment to be carried with the vehicle. Instead, there are three backpacks less than half a person's height. After opening the backpack and taking out the parts, a complete set of rock mechanics test equipment system can be assembled in five minutes.

Half of the large-scale infrastructure projects in China are rock mass projects located between mountains. Wu Faquan, the team leader and Chinese rock mechanics and engineering geology expert, said that a set of imported test system costs 8.5 million yuan, which is generally three or four meters high and weighs several tons, making it difficult to carry and assemble.

Wu Faquan decided to take teachers and students to carry out independent research and development in the direction of "lightweight and intelligent", which will last for 10 years. The team first used the lever principle and mechanical amplifier to develop the first generation of hand operated point load tester. Although the equipment specification was greatly reduced, the instrument was severely worn. Later, the team came up with the idea of using hydraulic pressure instead of hand cranking. By the fifth generation of equipment, multiple single equipment can be disassembled into several core components and loaded into backpacks.

In the process of R&D, the most difficult thing is the "size effect" - after the instrument size is reduced, are the parameters obtained still reliable? The team has absorbed the latest technology from many disciplines such as mechanical design, electronic circuit, software design, etc. by using the interdisciplinary platform in the school. It has spent five or six years to analyze three or four thousand sets of test data, finally solved the problem of parameter reliability after miniaturization, and also won five core patents.

Now, the "backpack laboratory" can finally show its power on the project site. The whole system is packed in three backpacks, each of which is only 15kg. At the entrance of a pumped storage power station project in Zhejiang Province, graduate student Zhang Yukai and his classmates carried out a point load test. Open the backpack, take out the load-bearing frame, loading equipment and console, place the loading system in the load-bearing frame, input the lithology and size of the test piece according to the test requirements, click the "Load" button, and the test will be completed in 1 minute. Wu Faquan introduced that the "backpack laboratory" completed on-site sampling, sample preparation and test at one time, saving more than 80% of the time compared with large indoor test equipment.

It is understood that the "backpack laboratory" of the school has been widely used in the scenes of expressways, railway tunnels, large-scale water conservancy and hydropower projects, and extends to new energy projects, geological disaster rescue and other fields. Only point load can complete more than 100 tests every day. Up to now, the team has participated in more than 30 field survey projects.