doi:10.16186/j.cnki.1673-9787.2023030064

Received:2023/03/27

Revised:2023/04/21

Published:2024/05/15

Characterization of 3D pore and fissure structure parameters of pressurized grouted body based on CT scan

ZHU Changxing1, WU Dazhi1, WANG Fenge2, SUN Jiaxin1

1.School of Civil Engineering，Henan Polytechnic University，Jiaozuo  454000，Henan，China 2.School of Computer Science and Technology，Henan Polytechnic University，Jiaozuo  454000，Henan，China

Abstract:  Objectives  In order to study the structural evolution characteristics of pores and fissures during the uniaxial compression of graded gravel specimens，   Methods  industrial CT scanning was performed in stages during the compression process. AVIZO was used to analyze the CT slices， reconstruct the 3D model of pore and fissure structure， and quantitatively characterize the characteristic parameters of pores， fissures and pore throats.   Results  The results show that the test blocks， under uniaxial compression， go through the stages of pore and fissure emergence， development， expansion， and penetration in turn. The characteristics of pore and fissure evolution are relatively obvious. The increase in pore number during the emergence stage is 14.41% without obvious penetration； the increase in pore number during the development stage is 326.91%， accompanied by a certain number of pore penetration； the decrease in pore number during the expansion stage is -57.79%. The maximum increase in pore equivalent diameter is 223.45%， and most of the pore and fissure characteristics are quantitative. Most of the pore penetration results in fractures； the number of pore fractures in the penetration stage is almost unchanged， with the maximum increase in pore equivalent diameter being 92.83%. Multiple fracture surfaces are formed after fracture penetration. After reaching the peak， connected pores appear in the test block， indicating complete development of pores and throats in the grouted body， ultimately leading to the destruction of the test block.   Conclusions  The results of the pore structure evolution characteristics during the microscopic destruction process of the injected body specimen block provide reference for the subsequent practice of fractured rock grouting engineering.

Key words:CT scan;grouted body;3D reconstruction;pore and fissure structure;pore-throat model