# 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. Mass-percent basis. Designed for analysis and ML-oriented workflows. Apache 2.0. Maintained by Sunnyday Technologies LLC, Appleton WI. 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.19647471 - Citation: Sonnentag, N. (2026). Open3DCP: Open Data Standard for 3D Concrete Printing. Sunnyday Technologies. - Maintainer: Sunnyday Technologies LLC (https://sunn3d.com) - Author: Nicholas Sonnentag (nickworks@sunn3d.com) - Contact: open3dcp@sunn3d.com - Current public version: v1.5 (2026-04-16); 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 records. - IS NOT: a dataset, a database service, a structural-design tool, or a substitute for any referenced standard. ## Design principles 1. Flat schema — every feature is a named column. No JSON nesting in ML-relevant fields. 2. Mass-percent basis — all material quantities stored as mass-% of total wet mix (water included, 0-100 scale). 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 (~20 columns): `cement_type_1`, `cement_type_1_2`, `cement_type_1l`, `cement_type_2`, `cement_type_3`, `cement_type_4`, `cement_type_5`, `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`. - 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`. - 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`. - 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 (solids basis): `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. ## Companion projects - CEMFORGE — AI-driven concrete mix-formulation platform intended to consume Open3DCP-formatted data: https://cemforge.ai - M3-CRETE — open-source meter-scale concrete 3D printer intended to produce Open3DCP-formatted data: https://m3-crete.com Open3DCP is the schema layer; CEMFORGE and M3-CRETE are companion projects rather than gatekeepers. ## 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 - Dataset JSON-LD: embedded in https://open3dcp.org/ inside a `