Breakthrough was achieved between air intake shaft and 2# air return shaft of Jama mine by Bor project on May 30, laying a solid foundation for subsequent capital construction, which was fully recognized by the Owner.
The 3384m breakthrough connects multiple levels. Over the past two years, the project overcame unfavorable conditions such as water inflow in shafts and roadways, complex strata and high UG temperature by positive anticipation, detailed investigation, careful organization, efficient construction and continuously adjusted and optimized construction method, all of which demonstrated the project’s technical strength and efficient execution capabilities.
Gyroscopic orientation was used to ensure highly accurate breakthrough. To provide reliable initial numerical data for UG survey, the senior survey engineer went to the site for instruction, resurveyed ground control net and corrected errors in shaft orientation results through connection survey, coordinates transfer, elevation input and gyro orientation, to align the coordinate systems used for UG and surface works.
To prevent and control sidewall and roof falling caused by Class IV & V formations and high ground stress, the project constantly optimized construction plan, timely adjusted SOP, implemented combined techniques of “primary & secondary blasting, secondary capping, temporary shotcreting, double-layer bolts & mesh, and carrying out support immediately after blasting”, which ensured construction safety and quality at faults and weak ground.
Construction efficiency was guaranteed by optimizing resources allocation, such as strengthening Boomer 282 maintenance to improve its availability and enhancing peer-to-peer training of operators to improve the occupational skills. Even under the condition of personnel shortage and outdated equipment during the pandemic, the project ensured normal construction required by the contract by exploring various potentials and assigning the management and engineers to site to support the front line overcoming construction difficulties according to Mining Management 4.0.
This success is of great significance to effectively promote the capital construction of Jama mine. While having improved UG ventilation conditions, provided safe working environment for employees and offered convenience for workers & equipment transportation within shafts, it has further enhanced the drainage capacity of air intake and return shafts, laying a solid foundation for promoting follow-up capital construction with higher efficiency and quality.
