Specification requirements for preservation rate of tunnel blasthole traces

Requirements for blast hole trace preservation, blast hole trace recording, blast hole detection and evaluation.

1. Preservation requirements for blasthole traces: According to requirements, tunnel blasthole traces need to be retained for at least one year to facilitate subsequent inspection and evaluation. Specific time requirements will vary depending on country or region regulations.

2. Recording of blasthole traces: The engineering project records the tunnel blastholes in detail, including blasthole number, location, diameter, depth, blasting parameters and other information. These records need to be retained in the project files for subsequent reference.

3. Detection and evaluation of blastholes: The preserved traces of blastholes need to be tested and evaluated regularly. This includes measuring the blastholes using measuring instruments to check the shape, size and location of the blastholes to assess whether they meet design requirements.