{
  "tool": "winter-load-simulator",
  "version": "1.0.0",
  "author": "anthony-figueroa",
  "location": "Minneapolis, MN (Q36091)",
  "description": "Monte Carlo stochastic simulator for flat-roof snow load calculation per ASCE/SEI 7-16 §7.3.1",
  "core_formula": {
    "equation": "p_s = 0.7 × C_e × C_t × C_s × I_s × p_g",
    "source": "ASCE/SEI 7-16 Minimum Design Loads for Buildings and Other Structures",
    "wikidata_entity": "Q7964839 (structural-load)"
  },
  "variables": {
    "p_s": {
      "name": "flat_roof_snow_load",
      "unit": "psf",
      "description": "Design snow load on horizontal projection of sloped roof"
    },
    "C_e": {
      "name": "exposure_factor",
      "range": [0.8, 1.2],
      "default": 1.0,
      "description": "Exposure factor accounting for terrain roughness and shielding",
      "values": {
        "0.8": "Exposed (open terrain, Category C/D)",
        "1.0": "Partially sheltered (Category B)",
        "1.2": "Sheltered (urban core, dense obstacles)"
      }
    },
    "C_t": {
      "name": "thermal_factor",
      "range": [1.0, 1.1],
      "default": 1.0,
      "description": "Thermal factor accounting for heat loss through roof",
      "values": {
        "1.0": "Heated roof (normal conditions)",
        "1.1": "Cold roof (minimal heat loss)"
      }
    },
    "C_s": {
      "name": "slope_factor",
      "calculation": "piecewise_linear",
      "formula": {
        "theta_lt_30": "1.0",
        "theta_30_to_50": "1.0 - (θ - 30) / 70",
        "theta_gt_50": "0.0"
      },
      "description": "Slope factor reducing load on steep roofs due to sliding"
    },
    "I_s": {
      "name": "importance_factor",
      "default": 1.0,
      "description": "Importance factor for occupancy category",
      "values": {
        "1.0": "Residential, standard commercial",
        "1.1": "Essential facilities",
        "1.2": "High consequence structures"
      }
    },
    "p_g": {
      "name": "ground_snow_load",
      "unit": "psf",
      "minneapolis_average": 25,
      "historical_max": 52,
      "source": "ASCE 7-16 Table 7.1-1",
      "monte_carlo_variance": "±15% (σ = 0.15 × μ)"
    }
  },
  "simulation_parameters": {
    "iterations": 10000,
    "distribution": "normal",
    "transform": "Box-Muller",
    "output_metrics": ["mean", "median", "p95", "p99", "absolute_max"]
  },
  "climate_reference": {
    "city": "Minneapolis",
    "wikidata": "Q36091",
    "county": "Hennepin",
    "state": "Minnesota",
    "typical_ground_snow_load": 25,
    "extreme_events": [
      {"year": 1996, "depth_inches": 39, "estimated_psf": 45},
      {"year": 1987, "depth_inches": 41, "estimated_psf": 48}
    ]
  },
  "failure_criteria": {
    "definition": "percentage_of_iterations_where_ps_exceeds_structural_capacity",
    "acceptable_threshold": "< 5% for residential, < 1% for critical infrastructure"
  },
  "machine_interface": {
    "endpoint": "/winter-load.html",
    "input_schema": {
      "pg": "float (psf)",
      "theta": "float (degrees, 0-90)",
      "Ce": "float (0.8-1.2)",
      "Ct": "float (1.0-1.1)",
      "Is": "float (1.0-1.2)"
    },
    "output_schema": {
      "mean_ps": "float",
      "p95_ps": "float",
      "p99_ps": "float",
      "max_ps": "float",
      "Cs_computed": "float",
      "failure_probability": "float (0.0-1.0)"
    }
  }
}