baseplate

Base Plate Design

Design and check a steel column base plate connection — base plate, anchor bolts, welds and the concrete below — with the SkyCiv standalone.baseplate API.

Prerequisite: open the session with standalone.baseplate.start, not S3D.session.start (verified: a check after S3D.session.start returns "Session has not been started. Please call standalone.baseplate.start first."). Auth, options and the { auth, options, functions } envelope are in skyciv-api-v3.

Only concentric column / plate / foundation layouts with symmetric anchors are supported.

Workflow

1. Choose design_code and load its reference file — it holds every accepted material, grade, diameter, electrode and the factors block for that code: American · Australian · Canadian · Europe.
2. Start from that code's sample-api/<country>/input.js (see Worked examples) and change only what you need. Every key must be present, even unused ones.
3. Send standalone.baseplate.start then standalone.baseplate.check in one request. design_obj is the arguments object — not nested under another key.
4. Check response.status. On 1, read errors / warnings / conflicts (below) and fix the input.
5. Scan every check for its ratio (see Reading the response).

"functions": [
  { "function": "standalone.baseplate.start", "arguments": { "keep_open": true } },
  { "function": "standalone.baseplate.check", "arguments": { "design_code": "American", "...": "..." } }
]

Several checks can follow one start in a request (verified; top-level response is the last). Each check takes about 11–20 s and uses one API credit.

Gotchas

• Invalid strings are silently replaced, not rejected. An unknown material, concrete grade or anchor diameter returns status: 0 with results computed on a default value (verified for column, base plate, anchor and concrete grades, and Canadian diameters). Copy values exactly from the reference file, and confirm the relevant capacity moved when you change one.
• Canadian anchor diameters are imperial sizes in mm (12.7, 15.9, 19.1, 22.2 …). The 12, 16, 20… list in the live docs is silently ignored — see canadian.md.
• A failing detailing check hangs the call instead of erroring. Verified with embed_plate (embedded plate side < 4 × anchor diameter): no conflicts are returned — the call runs until the server timeout (~45 s) and returns "standalone.baseplate.check timed out". options.timeout does not extend it. Treat any timeout as an input problem: check the detailing rules below against your geometry before retrying.
• My must be "0". It is reserved for future weak-axis support; any non-zero value ("1", "10") hangs the call until timeout.
• A fixed base needs a non-zero Mz in every load case. Otherwise status: 1 with the conflict "configured as a fixed support, but the load combination does not include a moment". Axial-only or axial + shear cases go on a pinned base.
• A wrong section name fails fast with an unhelpful message — "could not be completed for an unknown reason" in ~5 s. steel-column-database is the third level of the section library path and steel-column-profile the fourth (e.g. American › AISC › Pipes › Pipe6STD → "Pipes", "Pipe6STD"). Resolve both with section-selector.
• status: 0 does not mean the design passes — a run returned a breakout ratio: 1.248 with status: 0. Derive pass/fail from the ratios.
• capacity: 0 with ratio: 0 means "not evaluated", not a pass with infinite margin — e.g. Weld Capacity on an axial-only pinned base, Side-Face Blowout (Y-Direction) when no anchor is near that edge. Report these as N/A.
• Concrete Bearing Capacity sits at ratio: 1 for American/Canadian fixed bases under large moment. Ratio 1 = demand equals capacity (limit reached). This method takes bearing stress at its limit and solves for the bearing length, so the ratio stayed 1.000 when the plate grew 400 → 500 mm and the footing 450 → 900 mm. Report it as at-limit, but size the connection on the other checks — enlarging the plate won't move it. Small eccentricity (Nx = 200, Mz = 2) gave 0.102.
• Load values are strings ("Mz": "10") in every sample; keep them strings.
• Report URLs are temporary (solver.skyciv.com/temp/...).
• Strip screenshot before logging a failure — status: 1 responses carry a 60–200 KB base64 PNG of the calculator UI. Decode it only when diagnosing.