# Open3DCP > Open data standard / flat schema for 3D-printable concrete (3DCP) mix design and test records. Defines canonical column names, types, units, and engineering context for binders, alkali activators, aggregates, fibers, admixtures, pigments, fresh-state rheology, hardened mechanical properties, durability, 3DCP process parameters, and interlayer bond. kg/m³-primary basis (mass-% derivable). Designed for analysis and ML-oriented workflows. Apache 2.0. Maintained by Sunnyday Technologies LLC. This file is a high-density, plain-text summary intended for LLM retrieval and RAG indexing. Authoritative source is the GitHub repository and the schema document linked below. Open3DCP is a schema definition only — it does not contain mix-design data. ## Identity - Project name: Open3DCP (Open Data Standard for 3D Concrete Printing) - Live site: https://open3dcp.org - Repository: https://github.com/sunnyday-technologies/Open3DCP - License: Apache-2.0 (https://www.apache.org/licenses/LICENSE-2.0) - DOI: 10.5281/zenodo.19647470 (concept DOI; resolves to the latest version of record) - Citation: Sonnentag, N. (2026). Open3DCP: Open Data Standard for 3D Concrete Printing. Sunnyday Technologies. - Maintainer: Sunnyday Technologies LLC (https://sunn3d.com) - Author: Nicholas Sonnentag (open3dcp@sunn3d.com) - Contact: open3dcp@sunn3d.com - Current public version: v1.8.0 (2026-08-23); Status: Draft (under working-group review; review does not imply endorsement, certification, or affiliation with any standards body); canonical column list in Open3DCP_SCHEMA.md ## What it is, what it isn't - IS: a column-name / unit / type / semantic specification — a flat schema for 3DCP mix-design and test records. Scoped to extrusion-based (material-extrusion / FDM-style) 3D concrete printing. - IS NOT: a dataset, a database service, a structural-design tool, or a substitute for any referenced standard. Out of scope: particle-bed / binder-jetting, spray, and slip-form methods. ## Design principles 1. Flat schema — every feature is a named column. No JSON nesting in ML-relevant fields. 2. Dual basis, kg/m³ first-class (v1.7) — the constituent columns store mass-% of total wet mix (the self-normalizing projection); the source's kg/m³ (the industry/field standard) is preserved exactly, with total_batched_mass_kg_m3 (the sum of as-batched constituent masses, not a measured density) and total_binder_kg_m3 enabling lossless conversion in either direction and original_basis recording the source's basis. Use NULL when a value is unknown, not reported, not applicable, or not measured; use 0 only when a source explicitly reports absence or a true zero. 3. Standards-aligned — column naming follows ASTM C150 (cement types), C618 (fly ash), C989 (slag), C1240 (silica fume), C33 (aggregate grading). 4. 3DCP-native — first-class columns for nozzle geometry, layer timing, print speed, fresh-state rheology (yield stress, thixotropy, open time), and interlayer bond. 5. Multi-age — companion `strength_measurements` table stores test results from 1 hour through 365 days. ## Schema overview — main table `mix_designs` Material columns (all mass-% of total wet mix): - Binders (~45 columns): ASTM `cement_type_1`, `cement_type_1_2`, `cement_type_1l`, `cement_type_2`, `cement_type_3`, `cement_type_4`, `cement_type_5`; EN 197-1 (v1.8) `cem_i`, `cem_ii_a_s`, `cem_ii_b_s`, `cem_ii_a_v`, `cem_ii_b_v`, `cem_ii_a_l`, `cem_ii_b_l`, `cem_ii_a_ll`, `cem_ii_b_ll`, `cem_ii_a_m`, `cem_ii_b_m`, `cem_iii_a`, `cem_iii_b`, `cem_iii_c`, `cem_iv_a`, `cem_iv_b`, `cem_v_a`, `cem_v_b`; `cac`, `csa_cement`, `fly_ash`, `fly_ash_type_f`, `fly_ash_type_c`, `silica_fume`, `nano_silica`, `slag`, `metakaolin`, `limestone`, `pumice`, `bottom_ash`, `rice_husk_ash`, `cement_unspecified` (v1.7.5: type not stated — mass exact, type NULL), `cement_other` (v1.8: stated type with no dedicated column), plus carriers `cement_designation`, `cement_standard`, `cement_strength_class_mpa`, `cement_early_strength_class` (v1.8: exact printed designation + EN strength class, so any stated hydraulic cement records losslessly). - Commercial product identity (v1.8): `is_premixed`, `supplier`, `product_name`, `supplier_batch_number`, `production_date`, `bulk_density_kg_m3` — proprietary premixes record product + lot + water first-class; undisclosed constituents stay NULL (unknowable, not unreported). - Alkali activators (for AAM mixes): `sodium_hydroxide`, `sodium_silicate`, `potassium_hydroxide`, `potassium_silicate`, plus design parameters `activator_ms_ratio`, `na2o_dosage_pct`. - Modifiers: `nano_clay`, `mineral_powder`, `mwcnt`, `graphene_oxide`, `recycled_sand`. - Pigments: `iron_oxide_pigment`, `titanium_dioxide_pigment`, `chromium_oxide_pigment`, `carbon_black_pigment`, `pigment_other`. - Fine aggregates by FM: `mason_sand`, `fine_sand`, `concrete_sand`, `coarse_sand`; plus `fine_agg_unspecified` (v1.7.5: FM not stated — mass exact, bucket NULL) and the EN 12620 d/D fallback `agg_fraction_d_lower_mm`, `agg_fraction_d_upper_mm` (v1.8: fraction preserved exactly where no FM/sieve curve exists; FM stays the primary index). - Coarse aggregates by ASTM C33 size: `agg_size_89`, `agg_size_8`, `agg_size_7`, `agg_size_67`, `agg_size_6`, `agg_size_57`, `agg_size_5`, `agg_size_467`, `agg_size_4`, `agg_size_357`, `agg_size_3`, `agg_size_2`, `agg_size_1`; plus `coarse_agg_unspecified` (v1.7.5: max size not stated — mass exact, size class NULL). - Fibers: `steel_fiber`, `pp_fiber`, `glass_fiber`, `carbon_fiber`, `pva_fiber`, `basalt_fiber`, `nylon_fiber`, `aramid_fiber`, `cellulose_fiber`, plus characterization (`fiber_length_mm`, `fiber_diameter_mm`, `fiber_aspect_ratio`, `fiber_tensile_strength_mpa`). - Admixtures (basis recorded per row in `admixture_basis`: solids | as_delivered, v1.7.5): `superplasticizer`, `water_reducer`, `accelerator`, `calcium_formate`, `retarder`, `air_entrainer`, `vma`, `shrinkage_reducer`, `corrosion_inhibitor`. - Clay/VMA additives: `hpmc`, `sepiolite_clay`, `attapulgite`, `calcium_bentonite`. - Water and key ratios: `water`, `w_c_ratio`, `w_b_ratio`, `a_b_ratio`. Variables measured (target properties): - Hardened mechanical: `compressive_strength_mpa` (ASTM C39 / EN 12390-3), `tensile_strength_mpa`, `splitting_tensile_mpa` (ASTM C496), `flexural_strength_mpa` (ASTM C78), `elastic_modulus_gpa` (ASTM C469), `bond_strength_mpa` (ASTM C1583), `fracture_energy_n_m`, `density_hardened_kg_m3`, `poissons_ratio`. - Fresh state / rheology: `slump_mm` (ASTM C143), `spread_mm` (ASTM C1611), `yield_stress_pa`, `static_yield_stress_pa`, `dynamic_yield_stress_pa`, `plastic_viscosity_pa_s`, `thixotropy_pa_per_s`, `structuration_rate_pa_per_s`, `open_time_min`, `green_strength_kpa`, `air_content_fresh_pct` (ASTM C231), `unit_weight_fresh_kg_m3` (ASTM C138), `setting_time_initial_min`, `setting_time_final_min` (ASTM C191), `bleeding_pct` (ASTM C232), `j_ring_mm` (ASTM C1621), `v_funnel_s` (EN 12350-9), `l_box_ratio` (EN 12350-10). - 3DCP interlayer: `interlayer_bond_mpa` (ASTM C1583), `interlayer_shear_mpa`, `air_content_deposited_pct`, `void_area_fraction_pct`, `surface_roughness_avg`, `surface_moisture_state`, `surface_treatment`. - Durability: `chloride_rcpt_coulombs` (ASTM C1202), `chloride_migration_coeff` (NT BUILD 492), `carbonation_depth_1yr_mm` (EN 12390-12), `drying_shrinkage_28d_ue` (ASTM C157), `autogenous_shrinkage_ue` (ASTM C1698), `creep_coefficient` (ASTM C512), `freeze_thaw_durability_factor` (ASTM C666), `sulfate_expansion_6mo_pct` / `_12mo_pct` (ASTM C1012), `asr_expansion_14d_pct` (ASTM C1260), `asr_expansion_1yr_pct` (ASTM C1293), `abrasion_depth_mm` (ASTM C779), `water_penetration_depth_mm` (EN 12390-8), `electrical_resistivity_kohm_cm` (ASTM C1876), `porosity_pct` (ASTM C642), `water_absorption_pct` (ASTM C642), `sorptivity_mm_sqrt_s` and `sorptivity_secondary_mm_sqrt_s` (ASTM C1585), `scaling_resistance_kg_m2` (ASTM C672), `corrosion_rate_ua_cm2` and `half_cell_potential_mv` (ASTM C876), `heat_of_hydration_kj_kg` (ASTM C186). - Thermal & environmental: `thermal_conductivity_w_mk`, `specific_heat_j_kg_k`, `coeff_thermal_expansion_ue_c`, `fire_resistance_min` (ASTM E119), `embodied_carbon_kg_co2_m3`, `embodied_energy_mj_m3`. - Microstructure: `degree_of_hydration`, `calcium_hydroxide_pct`, `pore_size_distribution_nm`. 3DCP process parameters (null for cast specimens): - Extrusion / motion: `is_3d_printed`, `print_speed_mm_s`, `layer_height_mm`, `layer_time_gap_s`, `nozzle_diameter_mm`, `nozzle_shape`, `nozzle_area_mm2`, `filament_width_mm`, `layer_width_mm`, `extrusion_rate_l_min`, `num_layers`, `path_length_mm`, `infill_pattern`, `contour_count`, `print_direction`, `test_orientation`, `test_orientation_code`. - Pump: `pump_type`, `pump_pressure_bar`, `pump_rotational_speed_rpm`, `pump_distance_m`, `pipe_diameter_mm`, `pumping_duration_s`. - Mixing: `mixing_time_s`, `mixing_speed_rpm`, `mixer_type`, `shear_rate_per_s`, `admixture_addition_point`. - Environment: `mix_temperature_c`, `ambient_temperature_c`, `ambient_humidity_pct`, `wind_speed_m_s`. Provenance, quality, and exposure classes: - Provenance: `doi`, `source_citation`, `measurement_confidence` (measured/calculated/estimated/reported), `lab_name`, `provenance_notes`. - Quality flags: `is_training_ready`, `is_synthetic`, `outlier_flag`. - Exposure: `exposure_class_freeze`, `exposure_class_sulfate`, `exposure_class_chloride`, `exposure_class_water`, `exposure_class_asr`. Companion tables: `strength_measurements` (multi-age data), `sources`, `test_methods`, `curing_regimes`, `standard_test_ages`. ## Standards referenced ASTM C150, C595, C618, C989, C1240, C33, C494, C260, C39, C496, C78, C469, C191, C1611, C1583, C1202, C157, C666, C1260, C1293, C642, C1585, C672, C876, C186, C1611, E119. EN 197-1, EN 206, EN 12390 series, EN 12350 series. ICC 1150-2026 / 3D automated construction technology reference categories, RILEM TC 304-ADC, NIST MGI / Materials Data Repository, NASA GRC ICME Schema (Hearley & Arnold, 2023), and FAIR data principles. ## ICC 1150 compatibility Open3DCP maps representative material, mechanical, fresh-state, durability, fire, and process data categories used in emerging 3DCP wall qualification frameworks, including ICC 1150-2026. Open3DCP is not a compliance schema and does not replace professional engineering review, testing, or code approval. ## Ecosystem stance Open3DCP is the schema layer and is supplier-, hardware-, and platform-agnostic. Any formulation engine, printer, laboratory, or repository may produce or consume Open3DCP-formatted records; no particular product is required to use the schema. ## Machine-readable surface - Sitemap: https://open3dcp.org/sitemap.xml - robots.txt: https://open3dcp.org/robots.txt (explicitly allows ClaudeBot, GPTBot, Google-Extended, PerplexityBot) - MCP manifest (experimental): https://open3dcp.org/.well-known/mcp-manifest.json - Local MCP-style wrapper source: https://github.com/sunnyday-technologies/Open3DCP/tree/main/tools/mcp - Dataset JSON-LD: embedded in https://open3dcp.org/ inside a `