Necessary Measures During Excavation for Retaining Structures

Supervision and Qualified Execution

  • Engage qualified contractors and certified supervising engineers.

  • The supervising engineer and project manager must be present during excavation operations.

Retaining System Execution

  • Implement retaining systems based on design plans, specifications, and schedule.

  • If there’s a risk of wall collapse or sliding, install piles, sheet piles, or suitable anchors—unless the wall slope is less than the natural soil angle.

Special Risk Areas

When excavation is near highways, railways, or vibration-sensitive structures, additional reinforcement is required to prevent collapse.

Mandatory Inspections After Critical Events

Dewalls must be inspected and reinforced with proper anchors and safety equipment after:

  • Heavy rainfalls

  • Storms, floods, or earthquakes

  • Severe frosts

  • Explosions

  • Sudden collapses

  • Major damage to anchors

  • Any long interruptions in excavation activity

Use of Electrical Devices

  • For operations using electric motors (e.g., ventilation, water discharge), safety systems must comply with regulations.

Public Safety and Site Security

  • Excavation sites in public areas must be enclosed, with visible warning signs and traffic control measures to restrict unauthorized access.

Fall Prevention

  • Secure barriers must be placed to prevent falling materials, people, and machinery.

  • Avoid rainwater or groundwater runoff into the excavation.

Lighting and Hoisting Equipment

  • Provide adequate lighting around the excavation.

  • Install hoists and winches securely and professionally.

Air Quality and Gas Safety

  • For combustion engines used inside excavations, exhaust must be safely vented.

  • Use ventilation systems if toxic gases may accumulate.

  • Water accumulation in trenches must be pumped out.

Waste and Equipment Management

  • Do not dump excess soil, debris, or materials near the excavation edge.

  • Heavy machinery and unstable objects must not be placed at the edge.

  • Do not install site offices or worker rest areas near the excavation base or edge.

Structural and Soil Inspections

  • Daily inspections before stabilization; weekly after retaining system installation.

  • Inspections are also required after rain, earthquakes, explosions, or frost events.

Worker Safety Guidelines

  • Workers in deep excavations (>1m) must never work alone.

  • A safety officer must control vehicle access in large/deep excavation sites.

  • Post hazard signs at all access points.

Incident Reporting

  • The site supervisor must immediately report any accidents to the HSE unit before evidence is altered or lost.

Worker PPE and Machine Safety

  • All workers must wear helmets and safety boots.

  • Workers must stay out of machine operation zones.

  • Use mechanical tools—not manual lifting—for heavy items.

Scaffold and Ladder Safety

  • Scaffold setup and dismantling must be done under supervision by trained personnel.

  • Scaffolds must be firmly anchored—no use of loose bricks, barrels, or unstable bases.

  • Do not extend ladder height with boxes or lean ladders against round objects.

Additional Safety Measures

  • Install protective barriers to prevent falling objects from injuring workers.

  • For concrete pouring, install edge barriers to stop wheelbarrows from tipping.

Storage Safety

  • Cement or gypsum bags must not exceed 10 stacked layers unless secured and set back one bag every 5 layers.

  • Bricks and tiles must not be stacked over 2 meters high and must be enclosed.

Bitumen Heating

  • When heating bitumen drums, melt the top layer first and avoid direct flame at the bottom initially.

Adjacent Activity Safety

  • If workers are active near excavation, implement protective measures for their safety.

Excavation Waste Management

  • Do not dump excavated soil closer than 0.5 meters from the edge.

  • Avoid blocking pedestrian paths or roads with dumped materials.

Excavation Beneath Sidewalks

  • Reinforce with anchors and install warning signs, fences, and barriers.

Manual Digging Safety

  • Workers using picks and shovels must maintain safe distances from each other.

  • For trenches deeper than 1m and longer than 30m, provide one ladder per 30m, extending 1m above the edge.

Access Paths

  • Provide safe access routes for workers.

  • For excavations deeper than 6 meters, install landings every 6 meters along ladders or stairs with guardrails.

Vehicle Access

  • Access ramps for vehicles must be at least 4 meters wide, with strong side barriers (minimum 20 cm thick if wooden).

  • Ensure ramps are even and without surface irregularities.

Geotechnical Report Compliance

  • If site soil conditions (type, water level, qanats) differ from the geotechnical report, consult with the geotechnical consultant for re-evaluation.