What are the safety technical points of tunnel construction support?
2, the implementation of the construction organization design should be in accordance with the design requirements of the "Code" and "safety regulations", combined with the shape, appearance, water and cultural conditions, the excavation, support and lining technology should be selected, and detailed and specific safety technical measures should be formulated. During the construction, improvements and supplements should be made according to the quality situation, and technical disclosure of safety education should be made seriously.
3, weak surrounding rock, good quality, special quality or shallow buried, eccentric pressure, collapse of the tunnel cave should organize technical demonstration, determine the drilling and blasting, excavation and support scheme.
4. Ventilation pipes, high-pressure air pipes, water pipes, lighting lines, transmission lines, transportation roads and sidewalks in the cave should be planned in a unified way, and maintenance should be strengthened. Good mechanical equipment should be placed in a fixed storage location, materials should be neatly stacked, and special personnel should be responsible for the custody.
5. The construction in the hole shall be under the unified command of the foreman on duty, and the excavation and lining transportation operations shall be arranged reasonably according to the construction organization design, so as to reduce the mutual interference of crossing and interspersed.
6. Blasting excavation shall be designed. Smooth blasting or presplitting blasting technology should be adopted. It is necessary to strictly control the parameters such as the distance between peripheral holes and the charge of extrapolation angle to reduce the disturbance of surrounding rock and the number of overbreak.
7, the blaster should send blaster to check and deal with dangerous stones, hanging stones and set up monitoring to confirm safety. Its members must enter the working face to prevent the dust in the cave and reduce the dust concentration.
8, temporary support should comply with the standards of design documents, the distance should be less than the footage of two crops of guns.
9, grid arch shotcrete and anchor support should be strictly in accordance with the design standards to control the arch row spacing, anchorage degree, shotcrete thickness, and fill in the shotcrete and anchor support construction records for future reference (Appendix 5 of Technical Specification for Railway Tunnel Construction). Check the pullout resistance of the anchor, and extract 1 anchor every 300 groups, with no more than 3 in each group.
10, changing the type and standard of temporary support must be approved by the project management department, agreed by the design and supervision, and it is forbidden to lower the support standard on the construction site.
1 1, and adjust the progress of excavation and lining to control the unlined section. In general, the lining working face of 80m special quality section should follow the excavation working face closely.
12. The tunnel entrance should be arranged as soon as possible, so as to fully display the construction of each process. After lining 50 meters, portal end wall and wing wall should be made. After lining 100 meters (single mouth), the portal must be made.
13, design of ventilation system in the tunnel, take comprehensive dust control measures, regularly detect the concentration of harmful gas in dust, maintain and use ventilation facilities, and give priority to the supply of responsible communication equipment.
14, the power supply line of tunnel section must be laid. The tunnel section must be equipped with low-voltage lighting, power lines and cables, and laid overhead at a fixed position.
15, blasting equipment should establish a strict system of recipients and return. It is strictly prohibited to store it outside the warehouse. On-site foreman should be specifically responsible for the examination and approval of receiving goods, and master the quantity of receiving goods and returning to the warehouse.
16, transportation tracks and roads should be equipped with special liaison officers for maintenance of battery car drivers, and a call response system based on signal contact should be established. Non-passengers are strictly prohibited from taking transportation; Rail transport roads should be kept flat and drained, and isolation signs should be set between road transport roads; The technical standard of external channel ballast line should be defined to ensure safety.
17, propaganda slogans and warning signs should be equipped inside and outside the tunnel, so that operators can see them everywhere and raise their awareness of three injuries.
18. Full-time safety inspectors shall conduct a comprehensive inspection of the construction site in each shift, pay special attention to strengthening the inspection of the temporary supporting state of surrounding rock, let go of any slight change, record and find problems step by step, and ask the leaders to take measures to properly handle them. The construction technology department should carefully observe and measure the deformation of temporary support, and carefully process the recorded data to improve the construction according to the support parameters.
19, tunnel construction should formulate emergency plans to prevent landslides, water gushing and gas, equip with necessary emergency machinery and materials, and clearly organize employees to take measures to reduce the impact losses.
20. Arrange the culture and materials of the operators reasonably to create a good atmosphere for safe production, strengthen the surgical force in the clinic and equip it with necessary surgical rescue drugs and equipment, and set up a staff hospital to rescue the sick and wounded in the traffic area.