NB/T 11551-2024Standard for construction and acceptance of TBM method in coal mine roadway (English PDF)

Foreword

This document was issued on 24 May 2024 by the National Energy Administration of the PRC and takes effect on 24 November 2024.

It is a NB/T standard: recommended rather than compulsory, but it is the text a Chinese reviewer applies when assessing a submission.

It is classified under ICS 73.100.99, Chinese classification D 98.

This standard was prepared in accordance with the Notice of the General Department of the National Energy Administration on issuing the 2021 plan for the formulation and revision of industry standards in the energy field and the plan for the translation of foreign language versions, document Guo Neng Zong Tong Ke Ji [2021] No. 92, by China Coal Construction Group Co., Ltd., China Coal Tunnel Engineering Co., Ltd., China Coal No. 3 Construction (Group) Co., Ltd., Jincheng Hongsheng Construction Engineering Co., Ltd. and Jiangsu Shendun Engineering Machinery Co., Ltd. as chief drafting organizations, together with the participating drafting organizations concerned.

In the course of preparing this standard the drafting group carried out thorough investigation and research, carefully summarised the scientific and technological achievements and construction techniques that practice has proved mature and effective in recent years, sought the opinions of the organizations and experts concerned widely and in various forms, and after repeated discussion and study and several revisions finally settled the text.

This standard is divided into 13 chapters, comprising general provisions, terms, basic requirements, geological survey and prediction, parameter selection and system configuration of the TBM, construction preparation, assembly and demolition, driving construction, support, monitoring and information management, production auxiliary systems, safety, environmental protection and occupational health, and engineering quality acceptance.

This standard is administered by the National Energy Administration, and the China Coal Construction Association is responsible for its routine administration and for the adjustment and revision of parts of its content. The chief drafting organizations China Coal Construction Group Co., Ltd. and China Coal Tunnel Engineering Co., Ltd. are responsible for the interpretation of the specific provisions.

1 Scope

NB/T 11551-2024 is the Chinese standard for driving coal mine roadways with a tunnel boring machine, and for accepting the result. It exists because Chinese coal mining has moved to depths and to development lengths where the traditional method - drill, blast, muck out, support, repeat - has become the constraint on the whole mine. A drill and blast crew advances a few metres a day and every cycle stops production; an open type TBM breaks the full face, removes the muck on a belt and installs support continuously, and advances an order of magnitude faster. The obstacle has never been the machine but the setting: a TBM in a coal mine works in an explosive atmosphere, in a roadway too small to turn around in, launched from and received into chambers that have themselves to be excavated conventionally, with no route out except the way it came. The document is built around that reality. It defines the twenty-one terms the method needs, from the open type TBM itself and its main machine, back-up system, connection bridge, gantry, cutter head and cutting tools, through the minimum horizontal turning radius and the breaking out torque that the drive must deliver when the cutter head jams, to the four chambers - installation, starting, receiving and demolition - and the launching, stepping and trial driving sequence. It then follows the job in order: geological survey and prediction ahead of the face, TBM parameter selection and applicability evaluation for the ground expected, construction and site preparation, transport, assembly, debugging, site acceptance, demolition and transition to the next drive, then the driving itself including construction in special sections, attitude control and construction survey. Support gets its own chapter with seven methods, from rock bolt and cable through steel mesh, reinforcement row, steel band and steel arch to shotcrete. Monitoring and information management, the production auxiliary systems - transport, ventilation and gas prevention, water supply, drainage, power and compressed air - and the safety, environmental protection and occupational health requirements follow, and the last chapter sets the quality acceptance criteria for the driving, the support and the floor and ditch work. It was issued on 24 May 2024 by the National Energy Administration and took effect on 24 November 2024.

1.0.1 This standard is formulated in order to standardise the construction and acceptance of coal mine roadway works by the TBM method, and to guarantee construction safety and engineering quality.

1.0.2 This standard applies to roadway works in coal mines constructed by open type TBM.

1.0.3 The engineering design, the construction management, the engineering quality acceptance and the management of the engineering records of coal mine roadway construction by the TBM method shall comply with the provisions of this standard.

1.0.4 The engineering design and the construction of coal mine roadways driven by the TBM method shall actively promote the application of advanced and mature new techniques, new technologies, new equipment and new materials.

1.0.5 In addition to complying with this standard, the construction and acceptance of coal mine roadway works by the TBM method shall also comply with the provisions of the relevant current national and industry standards.

2 Terms

2.0.1 coal mine roadway TBM method

The construction method in which a coal mine roadway is driven by a complete set of TBM equipment that carries out rock breaking, support and muck removal in one pass.

2.0.2 full face rock tunnel boring machine

The special mechanical equipment that breaks the rock over the full face in one pass by means of a cutter head and provides support at the same time; abbreviated to TBM.

2.0.3 open type TBM

A TBM used in rock of relatively good stability, which removes the muck by belt conveyor and uses gripper shoes braced against the rock wall to take the driving reaction force and the torque, and which does not use segmental lining.

2.0.4 main machine

The collective name for the excavation, thrust, regripping and support devices of the TBM.

2.0.5 back-up system

The collective name for the equipment and structures located behind the connection bridge that provide the working support conditions for the main machine, including the back-up gantry and the auxiliary equipment.

2.0.6 connection bridge

The structure connecting the TBM main machine and the back-up gantry.

2.0.7 back-up gantry

The trailing mechanism located behind the connection bridge, used for mounting equipment, transporting materials and passage of personnel.

2.0.8 cutter head

The assembly of steel structure and cutting tools set at the front end of the TBM, which excavates the full face of the formation by rotation, oscillation or other motion.

2.0.9 cutting tools

The tools that cut or break the formation.

2.0.10 minimum horizontal turning radius

The minimum radius of horizontal curvature of a roadway that the TBM is able to construct.

2.0.11 breaking out torque

The maximum torque that the main drive unit can output for a short time when the cutter head cannot rotate under the rated working torque condition.

2.0.12 installation chamber

The roadway space underground in a coal mine used for assembling the TBM.

2.0.13 starting chamber

The length of roadway space into which the main machine or the complete machine assembled in the installation chamber is stepped, able to accommodate the TBM main machine and to allow its gripper shoes to brace against the chamber wall.

2.0.14 receiving chamber

The length of roadway space able to accommodate the TBM main machine or the complete machine after the TBM has reached the predetermined position and continued to advance to holing through.

2.0.15 demolition chamber

The roadway space underground in a coal mine used for dismantling the TBM.

2.0.16 starting base

The supporting device used for installing the TBM main machine and maintaining the launching attitude.

2.0.17 receiving base

The supporting device used for maintaining the TBM receiving attitude.

2.0.18 TBM launching

The construction process, after the TBM equipment has been installed, running from the preparation for driving until the equipment as a whole has entered the roadway; it includes stepping and trial driving.

2.0.19 TBM stepping

The process of advancing from the installation chamber to the working face.

2.0.20 TBM trial driving

The construction process in which, after the TBM has come close to the working face, it drives a certain distance so that its technical performance is fully understood and the normal advance parameters are determined.

2.0.21 TBM attitude

The spatial state of the TBM, generally expressed by the plan deviation, the level deviation and the pitch.