SAMPLE
Piping Toolset — Calculation Report
generated by calc-core · 2026-10-12

ASCE 7 Seismic Design Force (Fp) Calculator — for ASME B31E Piping Qualification — Sample Report

ProjectSample Project — Demonstration Only Job No.SAMPLE-001 Client—
CalculationASCE 7 Seismic Design Force (Fp) Calculator — for ASME B31E Piping Qualification Calc byPiping Toolset (calc-core) Checked byUNCHECKED — sample
Date2026-10-12 Rev0 BasisASCE 7 §13.3.1 seismic design force Fp (7-16 or 7-22 form) for ASME B31E qualification

1 · Design inputs

A piping component on a rack at roof level (z/h = 1) at a high-seismic site. S<sub>DS</sub> = 1.0 g from the site hazard data; a<sub>p</sub> = 2.5, R<sub>p</sub> = 6 and I<sub>p</sub> = 1.0 taken from the governing edition for this component; operating weight W<sub>p</sub> = 1,000 lb.

Spectral acceleration SDS1.0g
Amplification factor ap2.5—
Response modification Rp6—
Importance factor Ip1.0—
Height ratio z/h1.0—
Operating weight Wp1,000lb

2 · Method

Base equation for the horizontal force on a nonstructural component, ASCE 7 §13.3.1 Eq. (13.3-1) — the form changed at 7-22:

ASCE 7-05/-10/-16: Fp = 0.4 · ap · SDS · Wp · (1 + 2z/h) / ( Rp / Ip )

ASCE 7-22: Fp = 0.4 · SDS · Ip · Wp · ( Hf / Rμ ) · ( CAR / Rpo )

Both forms are then clamped between the minimum of Eq. (13.3-3) and the maximum of Eq. (13.3-2):

0.3 · SDS · Ip · Wp ≤ Fp ≤ 1.6 · SDS · Ip · Wp

lateral coefficient = Fp / Wp

7-16 terms: SDS the design spectral response acceleration at short period (g), ap the component amplification factor, Rp the component response modification factor, Ip the component importance factor, z/h the attachment height ratio (0 at grade, 1 at roof), and Wp the component operating weight. 7-22 replaces ap, Rp and (1+2z/h) with three factors: Hf, the height-amplification factor — Eq. (13.3-4) when the fundamental period Ta is known, or the simpler Eq. (13.3-5), Hf = 1 + 2.5·(z/h), when it is not; Rμ, the structure ductility reduction factor — Eq. (13.3-6), floored at 1.3 when the supporting structure's seismic force-resisting system is unspecified; and CAR and Rpo, the component resonance-ductility and strength factors from Table 13.5-1 (architectural) or 13.6-1 (mechanical/electrical) for the component type — table values that stay user inputs and are never embedded here. The calculator reports the unbounded Fp,raw, both bounds, the governing value, and which equation/edition produced it — so the clamp and the edition are both visible rather than silent.

3 · Calculation

  1. Height amplification: 1 + 2·z/h = 1 + 2·1 = 3 — the roof-level maximum. At grade (z/h = 0) this term would be 1, cutting the force by two thirds.
  2. Base equation: Fp = 0.4·ap·SDS·Wp·(1+2z/h) / (Rp/Ip) = 0.4·2.5·1.0·1,000·3 / (6/1) = 3,000 / 6 = 500 lb.
  3. Lower bound: 0.3·SDS·Ip·Wp = 0.3·1.0·1.0·1,000 = 300 lb.
  4. Upper bound: 1.6·SDS·Ip·Wp = 1.6·1.0·1.0·1,000 = 1,600 lb.
  5. 500 lb lies inside 300–1,600 lb, so neither clamp is active and the base equation governs: Fp = 500 lb.
  6. Lateral coefficient: Fp/Wp = 500 / 1,000 = 0.5 g applied horizontally to the component's operating weight.

4 · Results COMPUTED

Fp raw — base equation500lb
Lower bound 0.3·SDS·Ip·Wp300lb
Upper bound 1.6·SDS·Ip·Wp1,600lb
Fp — governing design force500lb
Lateral coefficient Fp/Wp0.5g
Governing expressionbase equation—

5 · Verification statement

The result values above are locked as fixture b31e-seismic.json, case “ASCE 7-16 (default edition): SDS=1.0, ap=2.5, Rp=6, Ip=1, z/h=1, Wp=1000 -> base governs”, tolerance 0.000001, in the calc-core continuous verification gate (see https://pipingtoolset.com/trust/validation.html). Allowable-stress and factor data are user-supplied inputs; citations: ASCE/SEI 7, Minimum Design Loads and Associated Criteria for Buildings and Other Structures — §13.3.1, horizontal seismic design force on nonstructural components: 7-16 base Eq. (13.3-1) with a<sub>p</sub>/R<sub>p</sub>/(1+2z/h), or 7-22 base Eq. (13.3-1) with H<sub>f</sub>/R<sub>μ</sub>/C<sub>AR</sub>/R<sub>po</sub>; both bounded by the maximum of Eq. (13.3-2) and the minimum of Eq. (13.3-3). · ASCE/SEI 7-22 — §13.3.1.1 Eq. (13.3-4)/(13.3-5), height-amplification factor H<sub>f</sub>; §13.3.1.2 Eq. (13.3-6), structure ductility reduction factor R<sub>μ</sub> (1.3 floor when the SFRS is unspecified); §13.3.1.3/§13.3.1.4, component resonance-ductility and strength factors C<sub>AR</sub>/R<sub>po</sub> from Table 13.5-1 (architectural) or 13.6-1 (mechanical/electrical) — table values user-supplied, never embedded. · ASCE/SEI 7 — §13.3.2 (7-10/-16 numbering), seismic relative displacements / anchor movement; outside the scope of this calculator. · ASME B31E, Standard for the Seismic Design and Retrofit of Above-Ground Piping Systems — §1.3, takes this F<sub>p</sub> (or site-specific seismic loading) as its required seismic input rather than defining its own force equation; the B31Ea-2010 addenda restrict a<sub>p</sub> = 2.5 / R<sub>p</sub> ≤ 3.5 when the force is used in a B31E §3.4 stress-limit check. · ASME B31.3, Process Piping — ¶302.3.6, allowable stresses for occasional loads, against which the resulting seismic stress is checked. · Factor values (S<sub>DS</sub>, a<sub>p</sub>/R<sub>p</sub>/z-h or H<sub>f</sub>/R<sub>μ</sub>/C<sub>AR</sub>/R<sub>po</sub>) are user-supplied from the governing edition — no code table values are embedded.

SAMPLE REPORT — auto-generated from a verification fixture to show the report format. Not a project calculation. ⚠ Engineering-aid tool. Public code equations; allowable-stress and factor data are user-supplied. Results MUST be independently verified and reviewed by a qualified/licensed engineer before any design, fabrication, or operation decision.