What are the safety technical specifications for tunnel construction?

1. Tunnel construction should be the focus of safety standard construction sites, carefully prepare construction site safety implementation standards, comprehensively plan, make reasonable arrangements, standardize command behavior, operation behavior and on-site production facilities, and implement standardized management.

2. The implementation construction organization design must follow the "Specifications", "Safety Regulations" and design requirements, combined with topography, geomorphology and hydrogeological conditions, and scientifically select excavation, support and lining methods and processes. , formulate detailed and specific safety technical measures. During construction, timely supplements and improvements should be made according to changes in geological conditions, and safety education and technical briefings should be carefully conducted.

3. For tunnels with weak surrounding rock, poor geology, special geology, or tunnels with shallow burial, partial pressure, or landslides, technical demonstrations should be organized to determine drilling and blasting, excavation, and support plans.

4. Ventilation ducts, high-pressure air ducts, water pipes, lighting lines, transmission lines, transport roads, and sidewalks in the cave should be planned in a unified manner, and maintenance should be strengthened to ensure that they are neatly laid out and in good condition. Mechanical equipment should be stored in fixed locations, materials should be stacked neatly, and dedicated personnel should be responsible for safekeeping.

5. Construction within the cave should be under the unified command of the on-duty foreman, and excavation, lining and transportation operations should be reasonably arranged according to the construction organization design to reduce overlap and mutual interference.

6. Blasting design should be made for blasting excavation. When using smooth blasting or pre-split blasting technology, parameters such as peripheral eye spacing, external insertion angle and charge amount must be strictly controlled to reduce disturbance to surrounding rocks. and the quantity of over-excavation and under-excavation.

7. After blasting, special personnel should be assigned to inspect, handle dangerous rocks and hanging rocks, and provide supervision. Only after confirming safety, other personnel are allowed to enter the working surface. Protect the cave from dust and reduce the dust concentration.

8. Temporary support should be based on the design documents and specifications. Generally, the maximum distance should not be greater than the footage distance of two guns.

9. The grille arch frame and shotcrete anchor support must strictly control the arch spacing and anchor rod spacing, anchor length, direction and concrete spray thickness in accordance with the design standards, and carefully fill in the "shotcrete anchor support" "Guarding Construction Records" for future reference (Appendix 5 of Technical Specifications for Railway Tunnel Construction). Check the pullout resistance of anchor rods, and sample one group for every 300 anchor rods, with no less than 3 anchor rods in each group.

10. Changing the type and standard of temporary support must be approved by the project management department and agreed by the design and supervision department. It is strictly prohibited to lower the support standards on your own at the construction site.

11. Timely adjust the excavation and lining progress and control the length of the unlined section. Generally, it should not be larger than 80 meters. The lining working surface in special geologically poor areas should closely follow the excavation working surface.

12. After the construction of each tunnel process is fully launched, the construction of the tunnel gate should be arranged as soon as possible. Under normal circumstances, the end wall and wing wall of the cave gate should be completed after 50 meters of lining is completed. In any case, when the lining is completed for more than 100 meters (single entrance), the tunnel gate must be prepared.

13. The ventilation system in the cave should be designed, comprehensive dust prevention measures should be taken, and the concentration of dust and harmful gases should be tested regularly. Establish a maintenance and use system for ventilation facilities and assign dedicated personnel to be responsible for them. Communication equipment should be prioritized to ensure timely supply.

14. In the Chengdong area, power supply lines must be properly erected. The un-Chengdong section must use low-voltage lighting and power cables for power supply, and they should be laid overhead at fixed locations.

15. A strict system for receiving and returning blasting equipment should be established, and storage outside the warehouse is strictly prohibited. On-site workers should be specifically responsible for the approval of use and control of the quantity used and returned to the warehouse.

16. Transport tracks and roads should be maintained by dedicated personnel. Battery vehicle drivers and liaison officers should establish reliable signal connections, implement a call-and-response system, and non-drivers and passengers are strictly prohibited from taking transport vehicles; trackless transport roads should maintain pavement Make it smooth and drain the accumulated water in time. When conditions permit, isolation signs should be set up between sidewalks and transport roads; technical standards should be clearly defined for temporary access roads outside the cave and ballast unloading lines to ensure safety needs.

17. Publicity slogans and warning signs should be set up inside and outside the cave so that workers can see them everywhere to increase the safety awareness of the "three no harms".

18. Full-time security personnel must conduct a comprehensive inspection of the construction site every shift. In particular, they must pay attention to strengthening the inspection of the surrounding rock and temporary support status, and do not miss any minor changes, and should pay attention to them step by step. Keep good records. If problems are discovered, promptly remind leaders to take measures and handle them properly. The construction technical department must carefully observe and measure the deformation of temporary support, and do a good job in recording and data processing, so as to correct the support parameters and improve construction methods.

19. Tunnel construction should formulate emergency plans to prevent collapse, water intrusion, gas, etc., equip with necessary rescue machinery and materials, clearly define the organization and division of labor, and take prompt measures to reduce impacts and losses when problems arise.

20. Reasonably arrange the cultural and material life of workers and create a good safety production atmosphere. The construction site medical room should strengthen its surgical capabilities and be equipped with necessary surgical rescue drugs and equipment. Staff hospitals should be set up in areas with inconvenient transportation to deal with the injured and sick in an emergency.