API: uplift plates & anchors

Runs either the strict Meyerhof–Adams/Das plate-breakout branch or the FHWA GEC 4 straight-shaft ground-anchor branch. The complete scientific scope and applicability limits are documented at Uplift plates & ground anchors.

Endpoint

The request is a union on kind. Both branches requireunitSystem, an exact method ID, and an explicitdesign basis.

• plate requires an explicit circular or rectangular shape, ordered uniform-strength layers, explicit groundwater state, effective plate weight (net of buoyancy where applicable), and uplift coefficient.
• anchor requires complete unbonded/bond geometry, traceable per-length bond transfer, efficiency and reference, tendon SMTS/EA, independent tendon-grout capacity, design and lock-off loads, and a production-test record or explicitnot-tested state.

Authentication, rate limits, and the error envelope are shared by every endpoint — see the API overview. Requests are unit-agnostic: any self-consistent unit system works, and results come back in the same units. The examples below use SI (m, kN, kPa, kN/m³).

Request fields

This table is generated from the same schema that validates the request, so it cannot drift. Where a field appears once per variant row, it belongs to that variant only.

Response fields

Code examples

A complete, runnable request. Replace YOUR_API_KEY (or set PILECALC_API_KEY in your environment).

curl https://api.pilecalc.com/v1/uplift \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "unitSystem": "si",
  "kind": "plate",
  "method": "method.uplift.meyerhof-adams-plate",
  "shape": {
    "kind": "rectangular",
    "width": 1.2,
    "length": 2.4
  },
  "embedment": 3,
  "layers": [
    {
      "type": "cohesionless",
      "top": 0,
      "bottom": 1.5,
      "gamma": 18,
      "phi": 31
    },
    {
      "type": "cohesionless",
      "top": 1.5,
      "bottom": 3,
      "gamma": 18,
      "phi": 31
    }
  ],
  "groundwater": {
    "mode": "dry"
  },
  "plateWeight": 4.5,
  "upliftCoefficient": 0.9,
  "design": {
    "basis": "asd",
    "factorOfSafety": 2
  }
}'

The GET variant returns nominalResistance,designResistance,method.id as a plain-text CSV line — made for Excel's WEBSERVICE() and Sheets' IMPORTDATA() (see Use PileCalc in Excel). Omit fields to get the full JSON response.

For extended-creep, supply testing.extendedCreepCycles: six ordered objects containing load, targetPressure, andreadings of timeMinutes, movement and pressure. Use coherent request units: metres and kPa, or feet and ksf; time is always minutes. GEC 4 Table 23 observation times must be complete. The existing scalar one/ten-minute fields remain required for compatibility but do not qualify an extended-creep record. The declared maximum must equal the highest recorded load. These are supplied-record checks, not verification of instrument calibration, the unloading sequence or project sampling.

Safety and migration

• The former width + area + soilType plate payload andgroutDiameter + bondedLength + adhesion anchor payload are rejected. They cannot identify plan geometry, units, groundwater, structural failure modes, or test status.
• Plate strength must be uniform. Sand additionally requires uniform unit weight and dry, fully submerged, or water-table-at/below-plate conditions. Clay permits variable unit weight and an internal water table in the integrated soil-weight term. There are no hidden water-unit-weight, plate-weight, bond-efficiency, or design-factor defaults.
• nominalResistance and designResistance are distinct. Do not apply a second factor to the design result.
• An anchor with testing.kind = "not-tested" returnsdesign-only-not-tested; it is not accepted for service.
• GET/Excel requests carry the identical JSON payload in req; response projection always retains mandatory scientific provenance fields.