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Impact Load Factor Calculator mechanism
The inspectable method record for Impact Load Factor Calculator, kept separate from implementation and qualification.
Model scope
The amplification formula itself is standard under its stated idealized assumptions. Verdict is NEEDS_REVIEW because the specification claims a peak-stress output without providing static stress or another stress-calculation input, and because the exact sudden-load and falling-load application models are not fully defined.
- The falling-load formula n=1+sqrt(1+2h/δst) is correct for an undamped, linear-elastic member when h is the drop distance before contact and δst is the static deflection caused by the falling load after it is applied.
- The sudden-load result n=2 at h=0 is correct only for an instantaneous step load on an initially stationary, linear, undamped elastic system; the specification does not define the load application model precisely.
- Dynamic deflection can be computed as δdynamic=n·δst, and peak stress can be computed as σdynamic=n·σst only when stress remains proportional to load. The listed inputs omit σst, so the claimed peak-stress output cannot be computed from the stated inputs.
- The phrase 'equivalent static load' is ambiguous: δst must correspond to the same load magnitude and structural configuration used for the impact calculation, not an unrelated static deflection.
Units and conventions
- h and δst must use identical length units before evaluating 2h/δst; the ratio is dimensionless.
- Dynamic deflection uses the same length unit as δst.
- Static and peak stress must use the same stress unit; the numerical stress unit is preserved when multiplied by n.
- h is assumed nonnegative and δst is assumed strictly positive.
- The test vectors include σst as an additional required input because peak stress is otherwise under-specified.
Inspectable vector
One of 4 source-bound review vectors:
{
"inputs": {
"h": 0,
"delta_st": 0.004,
"static_stress": 80,
"length_unit": "m",
"stress_unit": "MPa"
},
"expected_outputs": {
"impact_factor_n": 2,
"dynamic_deflection": 0.008,
"peak_stress": 160,
"length_unit": "m",
"stress_unit": "MPa"
},
"working": "2h/δst = 2·0/0.004 = 0. n = 1 + √(1 + 0) = 1 + 1 = 2. Dynamic deflection = n·δst = 2·0.004 = 0.008 m. Peak stress = n·σst = 2·80 = 160 MPa."
}Failure boundary
BREAK_CLAIMED · SELF_FLAGGED
The formula is undefined when static deflection is zero, and a negative signed height can produce a negative square-root radicand unless the input is explicitly interpreted as a nonnegative drop-height magnitude.
Other records
Sources and evidence
These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.
VERIFIED_LEDGER.jsonevidence-tranche5/tranche5-results.jsonBOUNDARY_HAZARD_CATALOG.json