NSCP 2015 — Site Coefficients
Input Parameters
Results

Enter parameters and click Calculate.

NSCP 2015 — Response Spectrum
Input Parameters
① Design Response Spectrum
② Time-History Reference (1.4× + period markers)
ADRS — Acceleration-Displacement Response Spectrum
Input Parameters

Site coefficients from NSCP 2015. Auto-filled when computed in the Site Coefficients tab.

Radial lines represent constant structural period T. Each line passes through the origin with slope 4π²/(g·T²). They help identify the effective period at any point on the ADRS curve.

ATC-40 Spectrum Reduction

Reduces the 5%-damped spectrum based on equivalent viscous damping from the structure's hysteretic energy dissipation (ATC-40 Chapter 8).

Type A: New buildings with stable, full hysteresis loops (e.g. ductile SMRF).
Type B: Average existing buildings with moderate energy dissipation.
Type C: Poor buildings with pinched or degrading hysteresis (e.g. unreinforced masonry).

Bilinear yield point — from the idealized pushover capacity curve.

Trial performance point — initial estimate where demand meets capacity. Uses Ti from initial stiffness to interpolate on the 5% ADRS.

Plot Layers

ADRS Plot
Pushover Capacity Curve (ADRS Format)

Enter pushover curve data converted to spectral coordinates. Sd = spectral displacement (m), Sa = spectral acceleration (g). Data should start from origin and represent the capacity curve in ADRS format.

Sd (m)Sa (g)
00
0.0050.050
0.0100.095
0.0150.135
0.0200.168
0.0270.200
0.0400.218
0.0600.230
0.0800.235
0.1000.238
0.1300.240
0.1700.242
0.2200.243
0.2800.244
0.3500.244
NSCP 2015 — Base Shear (Eq. 208-8 to 208-11)
Input Parameters
Results

Enter parameters and click Calculate.

NSCP 2015 — Structural Period Calculator
Input Parameters
Results

Enter parameters and click Calculate Period.

NSCP 2015 — Structural Redundancy (ρ)
Input Parameters
Results

Enter parameters and click Calculate.

PGA — Fukushima-Tanaka Attenuation Model
Input Parameters
Results

Enter parameters and click Calculate PGA.

Scaling Base Shear Calculator
Input Parameters
DirectionX (kN)Y (kN)
MAJOR106.274499.40
ORTHO4299.5085.74
Results

Enter parameters and click Calculate Scale Factors.

DPWH-BSDS — Design Response Spectrum
Input Parameters
BSDS Level II — Design Response Spectrum
BSDS Level I — EGM Response Spectrum
Results

Enter parameters and click Generate Spectrum.

DPWH-BSDS — Site-Specific Design Response Spectrum
Input Parameters
Site coefficients are not interpolated: Fpga = Fa = Fv = 1.0. Enter spectral values from a site-specific ground-motion hazard study.
Site-Specific Design Response Spectrum (Fa = Fv = 1.0)
Results

Enter parameters and click Generate Spectrum.

NSCP 2024 (8th Edition) — Design Response Spectrum
Input Parameters
NSCP 2024 — Design Response Spectrum
Results

Enter parameters and click Generate Spectrum.

ASCE 41 / ASCE 7 — Design Response Spectrum
Input Parameters
Leave blank to auto-fit the data.
Each curve is drawn with its own floor at its own level: 0.80 Sms under MCER, 0.80 Sds under the 2/3 design curve. They are the same ASCE 7-16 §21.3 / ASCE 41-17 §2.4.2 requirement stated at two levels — the 2/3 sits on both sides of the comparison and cancels, so the two floors never disagree. Compare like with like: a site-specific MCER against 0.80 Sms, a site-specific design spectrum against 0.80 Sds.
Both floors bound a site-specific spectrum, which this tab does not yet take as input. Until one is supplied they are reference lines only — not a limit on the curves plotted here.
ASCE 41 / ASCE 7 — Design Response Spectrum
Results

Enter parameters and click Generate Spectrum.

NSCP 2015 vs ASCE 41 — Design Spectrum Overlay
NSCP 2015 (Ca / Cv)
ASCE 41 / ASCE 7 (Ss / S1)
Spectra decay to near zero past ~4 s; lower this to fill the plot.
Leave blank to auto-fit the data.
Spectrum Overlay — plotted against actual period T
Notes
The two codes are built from different parameters — NSCP 2015 from Ca/Cv (Figure 208-3), ASCE from Ss/S1 with the 2/3 MCER factor. They are drawn here on a common actual-period axis so the shapes can be compared directly; the overlay is a comparison aid, not a code compliance check. The 80% line is the ASCE 7-16 §21.3 / ASCE 41-17 §2.4.2 floor on a site-specific spectrum — it is not a limit that the NSCP 2015 curve is required to satisfy.
Results

Enter parameters and click Generate Overlay.

ASCE 41-17 — BSE-1E & BSE-2E Response Spectra
Input Parameters
ASCE 41-17 — Seismic Hazard Spectra
Notes & Clause Basis

Generate the spectra to see the governing clauses.

Results

Enter parameters and click Generate Spectra.

OpenQuake — ASCE 41 Site-Specific job.ini
Inputs
Entered lat, lon. The generator writes them lon first — that is what OpenQuake's sites key expects — and restates the input pair in a comment.
7-22 needs 0.01–10 s. Against a 0.075–3.0 s logic tree the generator refuses rather than truncating the spectrum.
0 = unresolved. The source model dictates this, not the design code.
Paste the output of grep -rho 'investigation_time="[^"]*"' ssm/ | sort -u (or the XML itself). Takes precedence over the field above.
z1.0 in metres — 23.5 m is the CY08 default at VS30 = 760, and it must be a real positive depth. z2.5 in kilometres; 0 there — and only there — omits the key rather than carrying a wrong value.
Binding intersection of the eleven catalogue GMMs: 0.075 – 3.0 s. The floor is set by YoungsEtAl1997SInter and YoungsEtAl1997SSlab, the ceiling by AtkinsonBoore2003SSlabCascadia. Enter your own bounds only if you have swapped GMMs.
Comma-separated. Blank uses the ASCE 7 edition's own list.
[erf]
Intensity levels
Written as logscale(min, max, n) for PGA and every SA ordinate.
[output]
job.ini 
(fill in the site and click Generate job.ini)
Results

Enter the site and click Generate job.ini.

Notes — what OpenQuake does not give you

Generate the file to see the warnings and the post-processing that follows the run.

Pre-Run Checklist

Generate the file to see the checklist.

PEER → SGS Converter
Upload PEER Files

Upload one or more PEER NGA records (.AT2). Each file is converted to SGS format (numerical, decimal — no scientific notation). Time starts at t = DT.

Loaded Records
Summary
No records loaded.
Preview — Acceleration Time-History
SGS Generator — build a MIDAS .sgs from any data
File Header
Data
X is written as (i+1)×Δt, the way MIDAS indexes a record.
XY
0.0010
0.0020
0.0030
Preview
No data yet.
(click Preview)
PEER Ground Motion Record — Acceleration Time-History
Upload PEER GM Files

Upload one or more PEER NGA strong motion records (.AT2, .VT2, .DT2, .txt). Adding more files appends to the plot. Values expected in g.

Loaded Records
Summary
No records loaded.
Acceleration Time-History