GIDPC.Green Infrastructure · Disaster Prevention
Solutions

Urban Tree Safety

Street-Tree Safety · Fatigue Diagnosis

Cumulative wind-load fatigue life of street trees, assessed by ABAQUS dynamic FE and Monte Carlo, with species-, regional-, and soil-specific inspection thresholds.

ABAQUSKaimal Wind SpectrumRainflowMiner's RuleWeibullMonte CarloSobol Sensitivity

What this solves

Tree-risk assessment typically focuses on static ultimate-load thresholds. But cumulative fatigue from everyday wind loading — combined with decay-driven stress amplification — is the dominant cause of branch failure and windthrow during storms.

This solution is a probabilistic fatigue-life framework calibrated to Korean climate, species, and soil conditions, supported by Korean Ministry of Environment R&D (2022003570004).

How we analyze

| Step | Method | Output | |---|---|---| | 1. Geometry + material | DBH, height, species MOR | B31 tapered beam model | | 2. Decay-cavity geometry | Sonic tomography + Beta(2,2) prior | 10,000 eccentric samples | | 3. Wind time series | Kaimal spectrum, biaxial | Longitudinal + lateral series | | 4. Dynamic response | ABAQUS B31 + Rayleigh damping (ζ=2%) | Stress time series | | 5. Damage computation | Rainflow + Miner's rule | Cumulative damage D | | 6. Absolute-life translation | Regional Weibull wind distribution | Fatigue life in years | | 7. Uncertainty quantification | Sobol decomposition | 5th-percentile lower bound |

Demonstrated results

  • Decayed tree in Jeju typhoon belt: lower-bound fatigue life ~ 1.4 yr — immediate intervention required
  • Sound-tree fatigue-life spread across 5 Korean species: up to several hundred thousand-fold
  • Eccentric cavity geometry accounts for 99.6% of variance — sonic-tomography precision is the top priority
  • Clay soil: −64.5% basal stress (but elevated overturning risk)

Typical deliverables

  • Wind-load fatigue assessment report for your trees
  • Regional, species, and soil prioritization table
  • Visualizations (stress-time curves, damage distribution)
  • 5th-percentile-based risk decision guide