Publications by authors named "Zechao Chang"
Article Synopsis
- Thick-coal-seam mining faces challenges like long weighting intervals and strong rock pressure, impacting safety and efficiency.
- The study explores the formation mechanisms of these issues and how parting affects top coal caving performance (TCCP), proposing a hydraulic fracturing technique for better recovery during initial mining.
- Findings indicate that factors like roof thickness influence rock pressure, and a cantilever beam structure related to parting affects TCCP; the new fracturing technique effectively reduces rock pressure and improves coal release for safer operations.
Article Synopsis
- The study focuses on challenges faced in fully-mechanized top-caving mining in Jincheng, China, particularly high stress in adjacent roadways, severe deformation, and gas accumulation in corners.
- Analysis of coal and rock mechanical characteristics revealed the evolution of overlying strata structure during mining, highlighting the interaction between high-strength hard rock and low-strength coal.
- Proposed solutions include roadway reinforcement and gas drainage strategies that utilize techniques like pre-splitting and roof cutting to manage stress transfer and mitigate gas buildup.
Article Synopsis
- The study focuses on the mechanical behavior and strain energy changes in thick hard roof sandstone through uniaxial compression tests with acoustic emission monitoring, identifying multiple distinct phases in the stress-strain curve.
- The results show that both the acoustic emission energy and cumulative counts reflect significant stages that correlate with the stress-strain curve, confirming the different phases of material behavior.
- A damage constitutive model was developed to represent the relationship between stress and strain in these samples, illustrating how they experience strain hardening, softening, and eventual failure.
