The Open3DCP Schema: A Reference Standard for 3D Concrete Printing Data

Open3DCP. Apache License 2.0. Concept DOI: 10.5281/zenodo.19647471. Maintained by Sunnyday Technologies.

This page is the reference description of the Open3DCP schema for researchers, standards authors, journal editors, dataset curators, and software implementers. It is intended as a citeable companion to the canonical schema document at github.com/sunnyday-technologies/Open3DCP and the Open3DCP_SCHEMA.md reference. Where the schema document is exhaustive (every column, every type), this page is structural: it explains why the schema exists, what it covers, where it sits relative to the available standards landscape, and how a working laboratory can adopt it without changing how it runs experiments.

The argument is simple. 3D concrete printing (3DCP) is an active research field with hundreds of publications per year. Almost every paper reports a mix design, fresh-state behavior, hardened mechanical performance, and some characterization of the print process itself. Almost no two papers report these in the same way. Open3DCP is a flat, machine-readable schema that fixes the reporting layer without dictating the test methods. It sits above the experimental dataset and is cross-referenced (for interoperability convenience, not commitment) to current widely-used test method references. The schema is compatible with the available standards frameworks but not committed to any single one; newer measurement protocols, including in-line process telemetry, computer-vision-based bond inspection, and emerging digital-twin instrumentation, are first-class extensions as the field develops them.

1. The interoperability problem in 3DCP

3DCP literature has produced an enormous experimental record over the last decade and a half: rheology measurements, layer-bond pull-off tests, anisotropic compressive results, durability studies, recycled-aggregate variants, alkali-activated systems, fiber-reinforced printable mortars, and structural prototypes. The pace is high, with new mix designs, new test rigs, and new printing parameter combinations reported at conference and journal cadence.

Almost none of this data is directly reusable by another laboratory. There are several reasons.

First, units differ across labs and across publications. Mass percentages of binder are reported variously as fractions of the binder, fractions of total dry mass, or fractions of total wet mass. Water-to-binder ratios are sometimes water-to-cement ratios in disguise, depending on whether supplementary cementitious materials (SCMs) are counted as binder. Yield stress is reported in pascals or in kilopascals, or as torque from a vane that depends on the geometry of the apparatus. Slump-flow is reported in millimeters of spread, but the cone geometry and lift rate are often unstated.

Second, test methods differ. A "compressive strength" value can come from a mortar cube cast against a smooth wall and tested under ASTM C109 conventions; from a prism following EN 196-1, where two halves of a broken flexural specimen are then compressed; or from a printed cube cut from a multi-layer wall specimen and tested perpendicular, parallel, or at an angle to the print direction. The numerical answer alone does not communicate what was actually done.

Third, process parameters are buried in methodology prose. Layer height, layer time gap, nozzle diameter, nozzle shape, print speed, and pump pressure are reported, when reported at all, in narrative paragraphs rather than tabulated. Re-extraction is manual, error-prone, and expensive. Several large meta-analyses of 3DCP performance have noted explicitly that they could only recover a fraction of the variables they wanted from the published record.

Fourth, interlaboratory variance is large and largely undocumented. The RILEM Technical Committee 304-ADC (Assessment of Additively Manufactured Concrete Materials and Structures) is one of the active reference points here: it has worked since 2018 on common protocols for printability and printed-specimen testing. Its interlaboratory studies have reported substantial between-lab dispersion in nominally identical experiments, which is unsurprising for a field still developing its measurement consensus, but which becomes scientifically actionable only when the variance is visible in the data (RILEM TC 304-ADC, 2022; Wangler et al., 2019).

A schema does not fix the variance. A vane rheometer in one lab and a Brookfield in another will still produce different yield-stress numbers for the same paste. What a schema does is make the variance visible: it forces both labs to record the apparatus, the protocol code, the specimen geometry, and the value in a single, comparable structure. Once the variance is visible, statistical correction, hierarchical modeling, and data-driven calibration become possible. Without a schema, the variance is invisible because the data are not even in the same shape.

This is the gap Open3DCP addresses. It is the column reference that sits above the experimental dataset.

2. What Open3DCP is (and is not)

Open3DCP is three things and only three things.

1. A schema. A flat, named-column structure for 3DCP mix-design and test data. Every column has a name, an SI unit, a type, a description, and a reference to the standard that defines the underlying measurement. The schema spans rheology and fresh state, mechanical properties, 3DCP process parameters, durability, environment, specimen, interlayer, microstructure, and provenance domains.

2. A controlled vocabulary. Names are not free text. cement_type_1l is a Portland-limestone cement per ASTM C595 / EN 197-1 CEM II/A-L; it is not a Type I cement with a limestone addition. superplasticizer is recorded as solids-content mass percent of the wet mix, not as the as-supplied liquid percent. test_orientation_code takes one of {X, Y, Z, XY_45, CAST}. The vocabulary is the connective tissue that lets two datasets line up.

3. A column reference. Every column points outward to one of the available reference standards for the measurement: compressive_strength_mpa cross-references ASTM C39 and EN 12390-3; chloride_rcpt_coulombs cross-references ASTM C1202; freeze_thaw_cycles cross-references ASTM C666. The reference is informational only, and represents compatibility with current widely-used methods rather than commitment to any single one. Where newer measurement protocols emerge, the schema is designed to extend rather than to be replaced. Open3DCP does not redefine the test; it tells you which test the column is meant to capture.

Open3DCP is licensed under the Apache License, Version 2.0, including an express grant of patent rights from contributors. The canonical version is deposited on Zenodo with concept DOI 10.5281/zenodo.19647471, which resolves to the most recent versioned release. The repository is at github.com/sunnyday-technologies/Open3DCP.

It is equally important to be clear about what Open3DCP is not.

• Open3DCP is not a database. It defines column names and types; it does not host data. Researchers deposit their datasets on Zenodo, 4TU.ResearchData, the UCI Machine Learning Repository, or institutional repositories of their choice. Open3DCP gives them a target shape for the deposit.

• Open3DCP is not a benchmark. There is no Open3DCP test set, no leaderboard, no canonical performance number to beat. Benchmarks are downstream artifacts that some users may build on top of Open3DCP-shaped data; the schema itself takes no position on what is "good."

• Open3DCP is not a substitute for a standard. ASTM C39 still describes one way to test a cylinder. EN 12390-3 still describes one way to test a cube. RILEM TC 304-ADC still develops 3DCP-specific test protocols. Other emerging protocols will join them. Open3DCP does not replace any of these and does not privilege any of them; it records their results in a uniform shape.

• Open3DCP is not a regulatory document. Building codes (IBC, Eurocode), material specifications (ACI 318, EN 206), and the emerging ICC 1150 standard for 3D-printed concrete walls (ICC, 2024 draft) define what concrete must be for construction. Open3DCP is a research data format. It happens to map cleanly onto ICC 1150 categories (see Section 4), but it does not certify anything.

The intended audience is researchers, dataset curators, journal editors enforcing supplementary-data conventions, ML practitioners training surrogate models, and standards bodies developing 3DCP test methods. The intended use is to make 3DCP data interoperable across labs, not to homogenize the underlying experimental practice.

3. The schema's variables across rheology, mechanical, process, and durability domains

The Open3DCP schema is organized into measured-variable groups across primary domains: rheology and fresh state, mechanical properties (hardened), 3DCP process parameters, and durability. The accounting is detailed in the CHANGELOG and the schema reference. This section walks through the groups with examples, giving enough orientation for a reader to find the corresponding section of the schema document.

3.1 Composition (binders, aggregates, fibers, admixtures, water)

All composition columns are stored as mass percent of total wet mix. This convention, fixed in the v1.0 design, eliminates density assumptions and normalizes naturally to a percent scale. The cementitious portion is indexed by familiar Portland and Portland-limestone cement classifications (cement_type_1, cement_type_1_2, cement_type_1l, cement_type_2, cement_type_3, cement_type_4, cement_type_5), cross-referenced to ASTM C150 / EN 197-1 for interoperability, plus calcium aluminate (cac) and calcium sulfoaluminate (csa_cement). Supplementary cementitious materials are split into bins compatible with ASTM classification conventions: fly_ash_type_f (cross-referenced to ASTM C618 Class F), fly_ash_type_c (ASTM C618 Class C), silica_fume (ASTM C1240), slag (ASTM C989), metakaolin (ASTM C618 Class N), and limestone (EN 12620). Recent releases have added alkali-activator columns (sodium_hydroxide, sodium_silicate, potassium_hydroxide, potassium_silicate, activator_ms_ratio, na2o_dosage_pct) for geopolymer and alkali-activated slag systems, plus pigment columns for architectural 3DCP.

Aggregates use US-industry sand grade names cross-referenced to ASTM C33 fineness modulus ranges (mason_sand, fine_sand, concrete_sand, coarse_sand) plus the ASTM C33 size-number system for coarse aggregate. Most 3DCP systems are limited to smaller aggregate sizes because of pump and nozzle constraints; the larger sizes are present for compatibility with conventional concrete data and for future large-nozzle systems.

Fibers are split by material (steel_fiber, pp_fiber, pe_fiber, pva_fiber, glass_fiber, basalt_fiber, carbon_fiber, nylon_fiber, aramid_fiber, cellulose_fiber) with three characterization columns that capture the form factor: fiber_length_mm, fiber_diameter_mm, and fiber_aspect_ratio (L/d). Cellulose fiber (cross-referenced to ASTM D7357 where applicable) was added for compatibility with ICC 1150 material categories.

Admixtures are recorded as solids-content mass percent, not as-supplied liquid percent: a polycarboxylate dosage given as a fraction of a partly-aqueous product is recorded after multiplying by the solids fraction. The columns are cross-referenced to ASTM C494 admixture types where applicable: superplasticizer (Type F/G), water_reducer (Type A), accelerator (Type C/E), retarder (Type B/D), air_entrainer (ASTM C260), vma, shrinkage_reducer, and the specialized rheology modifiers hpmc, sepiolite_clay, attapulgite, and calcium_bentonite.

3.2 Rheology and fresh state

The rheology group (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) captures the parameters that govern 3DCP printability. These are typically measured with a vane rheometer or a parallel-plate rheometer; the schema does not enforce a specific apparatus but expects the test method to be recorded in test_method_code.

The workability group (slump_mm cross-referenced to ASTM C143; spread_mm cross-referenced to ASTM C1611 or the ASTM C1437 flow table; j_ring_mm to ASTM C1621; v_funnel_s to EN 12350-9; l_box_ratio to EN 12350-10) captures conventional flow tests carried over from self-consolidating concrete practice.

Setting time uses Vicat-needle measurements (setting_time_initial_min, setting_time_final_min, cross-referenced to ASTM C191), and buildability is captured as green_strength_kpa. Air content (air_content_fresh_pct, cross-referenced to ASTM C231), unit weight (unit_weight_fresh_kg_m3, ASTM C138), and bleeding (bleeding_pct, ASTM C232) round out the fresh-state battery.

3.3 Mechanical properties (hardened)

Compressive strength (compressive_strength_mpa, cross-referenced to ASTM C39 or EN 12390-3 where applicable) is the most-reported variable in 3DCP literature, but it is also the most ambiguous because of specimen geometry and test orientation. The schema separates the value from its context: specimen_geometry, specimen_length_mm, specimen_width_mm, specimen_height_mm, test_orientation, and test_orientation_code together describe how the test was actually run. For a 3DCP literature review, recording (cube, perpendicular) versus (prism, parallel) versus (cast cylinder, no orientation) is the difference between meaningful comparison and apples-to-rocks.

Other mechanical columns include tensile_strength_mpa, splitting_tensile_mpa (cross-ref ASTM C496), flexural_strength_mpa (ASTM C78), elastic_modulus_gpa (ASTM C469), bond_strength_mpa (ASTM C1583), fracture_energy_n_m (RILEM FMC-50), toughness_index (ASTM C1018), and density_hardened_kg_m3 (ASTM C642). The cross-references are interoperability hooks rather than methodological commitments.

3DCP-specific interlayer columns are split out: interlayer_bond_mpa (pull-off, cross-ref ASTM C1583), interlayer_shear_mpa, air_content_deposited_pct, void_area_fraction_pct, surface_roughness_avg, surface_moisture_state, and surface_treatment. Interlayer behavior is the dominant 3DCP-specific failure mode, and Chen et al. (2020) showed that bond strength can drop substantially when the layer time gap is extended past the printability window, with porosity at the interface as the controlling mechanism.

3.4 Process parameters

The 3DCP process group is what distinguishes Open3DCP from conventional concrete schemas. Columns include is_3d_printed (boolean), print_speed_mm_s, layer_height_mm, layer_time_gap_s, nozzle_diameter_mm, nozzle_shape, nozzle_area_mm2, filament_width_mm, extrusion_rate_l_min, num_layers, path_length_mm, infill_pattern, and print_direction. The pumping subgroup (pump_type, pump_pressure_bar, pump_rotational_speed_rpm, pump_distance_m, pipe_diameter_mm, pumping_duration_s) and mixing subgroup (mixing_time_s, mixing_speed_rpm, mixer_type, shear_rate_per_s, admixture_addition_point) capture the production line that delivers the printable mix to the nozzle.

Environmental conditions during printing (mix_temperature_c, ambient_temperature_c, ambient_humidity_pct, wind_speed_m_s) matter for cold-joint formation and surface drying, both of which affect interlayer bond.

3.5 Durability

The durability group covers chloride transport (chloride_rcpt_coulombs, cross-ref ASTM C1202; chloride_migration_coeff, NT BUILD 492; chloride_diffusion_coeff, ASTM C1556), carbonation (carbonation_depth_1yr_mm, EN 12390-12), shrinkage (drying_shrinkage_28d_ue, ASTM C157; autogenous_shrinkage_ue, ASTM C1698), creep (creep_coefficient, ASTM C512), freeze-thaw (freeze_thaw_cycles, ASTM C666), sulfate attack (sulfate_expansion_6mo_pct, ASTM C1012), ASR (asr_expansion_14d_pct, ASTM C1260; asr_expansion_1yr_pct, ASTM C1293), permeability (water_penetration_depth_mm, EN 12390-8; electrical_resistivity_kohm_cm, ASTM C1876), and absorption (water_absorption_pct, ASTM C642; sorptivity_mm_sqrt_s and sorptivity_secondary_mm_sqrt_s, ASTM C1585). Each cross-reference points at one of the available test frameworks; emerging durability protocols (electrochemical impedance spectroscopy, accelerated multi-ion exposure, embedded sensors) extend the schema as the field develops them.

The secondary sorptivity column is particularly relevant for 3DCP because it characterizes interlayer-zone moisture transport at no extra laboratory cost: it is the same C1585 specimen, the same test, just a different segment of the absorption curve.

3.6 Provenance

Every record carries provenance: doi, source_citation, measurement_confidence (one of measured, calculated, estimated, reported), lab_name, and provenance_notes. The lab_name field is the linchpin of interlaboratory analysis: it lets a meta-analyst compute lab-level random effects without having to reconstruct lab identity from authorship strings.

4. Cross-references to existing standards

Open3DCP fields are cross-referenced to the available standards landscape for interoperability convenience. The four major bodies most often present in the literature today are ASTM International, the European Committee for Standardization (CEN/EN), the American Concrete Institute (ACI), and RILEM. Newer cross-cutting documents include the ICC 1150 draft for 3D-printed concrete walls (ICC, 2024) and NIST guidance on materials data management. The schema treats these as compatibility hooks rather than methodological commitments: it is open to additional cross-references and to newer measurement protocols as the field develops them.

The table below is a compact mapping; the canonical mapping is in Open3DCP_SCHEMA.md, which carries one row per column.

The recently published ICC 1150 draft (IS-3DACT committee, ICC, 2024) is one of the first US consensus standards for 3D-printed concrete walls. It cites ASTM C150, C595, C33, C494, C143, C1437, C231, C138, C403, C39, C109, C469, C157, C1583, E518, C666, C1260, C1202, C1585, A820, D7508, D7357, and E119. Each of these maps to an Open3DCP column. RILEM TC 304-ADC publications (Reinhardt et al., 2019; Wangler et al., 2022), among other available reference points, describe orientation nomenclature and protocol structure that the schema's test_orientation_code enumeration is compatible with.

The mapping is one-way and informational. Open3DCP makes no claim that a column "satisfies" the cited standard; it claims that the column records the result of a test performed under one of the available reference frameworks. The distinction matters legally and methodologically, and is restated in the schema disclaimer.

5. A worked example

To make the schema concrete, consider an illustrative 3DCP experiment. The Sunnyday Materials Lab prints a multi-layer test wall using a Portland-limestone-cement (PLC) based mortar with fly ash replacement and polypropylene fiber. Cubes are extracted from the printed wall, plus cast control cubes, and tested at the standard reporting age.

The mix design records, in canonical Open3DCP shape:

• Type IL Portland-limestone cement (cross-ref ASTM C595 CEM II/A-L) as cement_type_1l
• Class F fly ash (cross-ref ASTM C618) as fly_ash_type_f
• Concrete sand (cross-ref ASTM C33) as concrete_sand
• PCE superplasticizer recorded at solids-content basis as superplasticizer
• HPMC viscosity modifier as hpmc
• Polypropylene fiber, with fiber_length_mm, fiber_diameter_mm, and fiber_aspect_ratio filled in as pp_fiber
• Water as water and the derived w_b_ratio

Process columns capture nozzle, layer, speed, layer time gap, ambient conditions, and mix temperature. Test columns capture the spread, the static yield stress at the time of pumping, the orientation (Z, Y, or CAST), and the test method code.

The corresponding Open3DCP CSV row is fully self-describing. A consumer that has never seen this dataset can identify the print orientation, the test method, the lab, and every material composition entry from the row alone. Where two compressive results come from the same mix but different orientations, they are recorded as separate rows that share a mix_id prefix and differ only in test_orientation_code; an ML pipeline can group or condition on orientation at training time. The lab_name and measurement_confidence fields enable downstream meta-analysis to weight or partition by lab and by data quality.

The same record is machine-extractable for ML training without any parsing logic beyond reading a CSV. This is the central design property of the schema and the reason for the flat structure: every column is a feature, every row is an observation, no JSON traversal is required for the model to consume the data.

The schema also supports JSON-LD wrapping for deposit alongside Zenodo records. The minimal wrapper points the consumer at the Open3DCP vocabulary (@vocab: https://open3dcp.org/schema/) and declares the schema version (open3dcp:schema_version) so consumers can detect breaking changes between major versions. CEMFORGE, the Sunnyday Technologies AI platform for printable concrete optimization (cemforge.ai), consumes Open3DCP-shaped data directly. Hardware platforms such as M3-CRETE (m3-crete.com) generate Open3DCP-shaped logs from their print controllers as the data are produced.

6. Adopting Open3DCP in your lab

The schema is designed so that adoption does not require changing how your lab runs experiments. It requires only that the results are recorded in a uniform shape on the way out. The recommended workflow is three steps.

Step 1: Map your existing CSV columns to Open3DCP keys. Most laboratories already keep a mix-design spreadsheet with columns for each material, plus a results spreadsheet with columns for the tests. The mapping from your column names to Open3DCP column names is usually a one-time alias table. The schema document includes a substantial seeded alias list from the literature: "GGBFS," "ground granulated blast-furnace slag," and "slag" all map to slag; "C33 sand," "concrete sand," and "natural sand" all map to concrete_sand. Where you store densities and compute mass-percent on the fly, do that conversion once at export time so the deposited file is in the canonical shape.

Step 2: Wrap the CSV with a JSON-LD context. The minimal wrapper points the consumer at the Open3DCP vocabulary and declares the schema version (open3dcp:schema_version) so consumers can detect breaking changes between major versions. A complete deposit usually includes the CSV file (one row per measurement), a JSON-LD sidecar with the dataset-level metadata (authors, license, description, related identifiers), and the schema version reference. Templates are in the GitHub repository under examples/.

Step 3: Validate with tooling that consumes Open3DCP-shaped reports. Validation harnesses, including CADCLAW (the open-source CAD validation framework that ships with M3-CRETE), are able to round-trip Open3DCP rows directly: an Open3DCP record describing a printed specimen can be tied back to the CAD-validated geometry that was deposited. This kind of cross-tool integration is the reason the Open3DCP schema is flat and stable: it lets independent tools (formulation engines, hardware controllers, CAD validators, statistics packages) share the same record without bespoke adapters.

Step 4: Deposit on Zenodo, 4TU.ResearchData, or your institutional repository. Use a CC BY 4.0 license for the data itself (this is independent of the Apache 2.0 license on the schema). Add the Open3DCP @id reference to the metadata so search engines and citation tools can link your dataset to the schema. Mint a DOI. Cite both Open3DCP (using the Zenodo concept DOI, 10.5281/zenodo.19647471) and any test methods you used in your dataset description.

A working lab can complete these steps for an existing dataset in an afternoon. The harder cases are legacy datasets where the experimental record is incomplete, and there the schema is honest: missing columns are simply null, and the measurement_confidence field flags the cells that were reconstructed from narrative prose. Open3DCP does not pretend that legacy data are as good as primary measurements, but it does let you publish them in a comparable shape with the limitations recorded explicitly.

7. Where Open3DCP fits relative to the available standards landscape

Reference frameworks in materials science are layered. From the lab bench upward, here is how the available standards landscape commonly looks today (one snapshot, not a fixed hierarchy):

+------------------------------------------------------------+
|  Building codes and design standards                       |
|  IBC, Eurocode, ACI 318, EN 206, ICC 1150 (3DCP walls)     |
+------------------------------------------------------------+
|  Material specifications                                   |
|  ASTM C150, C595, C618, C989, C1240, C33, C494, EN 197-1   |
+------------------------------------------------------------+
|  Test method standards                                     |
|  ASTM C39, C78, C496, C469, C1202, C1585, C666, C1260,     |
|  EN 12390-3, RILEM TC 304-ADC, NT BUILD 492                |
+------------------------------------------------------------+
|  Open3DCP schema (this layer)                              |
|  Column names, units, types, controlled vocabulary         |
|  Apache 2.0, DOI 10.5281/zenodo.19647471                   |
+------------------------------------------------------------+
|  Experimental datasets                                     |
|  Per-lab CSVs, supplementary materials, Zenodo deposits,   |
|  4TU.ResearchData, UCI ML Repo, institutional repositories |
+------------------------------------------------------------+
|  Raw measurements                                          |
|  Rheometer logs, load cell traces, image stacks, etc.      |
+------------------------------------------------------------+

The standards layer above describes what to measure and how to measure it under current widely-used methods. The schema layer says how to record what you measured. The dataset layer says what the actual numbers are. The schema is informational with respect to the reference frameworks above (it cross-references them, but is not committed to any single one) and prescriptive only with respect to the datasets below (it tells them what shape to take). It is intentionally thin: it does not redefine ASTM C39, it does not specify an apparatus, it does not approve a test, it does not certify a lab. It just tells you where to put the answer, in a way that is open to newer measurement protocols as the field develops them.

This positioning matters because there is no other layer that does this. ASTM and EN do not publish digital schemas. RILEM publishes recommendations, not column reference documents. NIST publishes data management guidelines (Hearley and Arnold, 2023; Materials Genome Initiative materials) that describe the principles a schema should follow, but does not maintain a 3DCP-specific schema. Open3DCP fills the gap, and it does so in a license (Apache 2.0) and a format (flat CSV plus JSON-LD) that allow downstream reuse without negotiation.

8. Roadmap: where the schema is going

The schema is on a quarterly minor-version cadence. Major versions are reserved for breaking changes that would force existing datasets to migrate, and the maintainers commit to making such changes rare. The current planned additions and known gaps:

Planned for upcoming releases:

• Long-term durability columns. The schema currently captures medium-horizon carbonation and sulfate expansion; multi-year exposure data (carbonation, ASR) is not yet first-class. A working group is reviewing the right column granularity.
• Embodied carbon LCA fields beyond embodied_carbon_kg_co2_m3 and embodied_energy_mj_m3. The current columns are cradle-to-gate; cradle-to-grave and module-level (A1 through A5) breakdowns are useful for green-procurement reporting that cross-references EN 15804, ISO 21930, and other emerging LCA frameworks.
• Surface finish characterization. Architectural 3DCP applications need quantitative surface-roughness columns beyond the current single-value surface_roughness_avg. Candidates include Sa, Sq, and Sz from areal-roughness measurement standards.
• Pumping power and energy columns to support energy-per-cubic-meter analyses. The current pump_pressure_bar and extrusion_rate_l_min allow derivation but do not record the recorded power directly.
• Robotic and gantry kinematic envelope fields. Cell geometry, build envelope, and reachable orientations matter for printability comparison across machines.
• Closer integration with the M3-CRETE log format so that hardware-generated print logs map one-to-one onto schema columns at runtime.

Honest gaps:

• The schema is biased toward extrusion-based 3DCP. Selective binder activation, particle-bed printing, and shotcrete-based 3DCP are partially covered but not first-class.
• Microstructure characterization is sparse. SEM image references, XRD pattern hashes, and MIP curve summaries are not yet schema fields. Image-level data are better hosted as separate Zenodo records linked by DOI.
• Sustainability metrics beyond embodied carbon are out of scope for the v1 series.

Invitation to contribute. The schema is community-maintainable. Issues and pull requests are welcome at github.com/sunnyday-technologies/Open3DCP. Proposed columns should come with: (1) a clear naming convention, (2) a unit, (3) a reference standard or, where no standard exists, a citation to the literature defining the measurement, (4) a use case from the proposer's own work. Major changes are discussed in issues before being merged into a release.

Cite Open3DCP

If you reference Open3DCP in a paper, dataset, or technical report, please cite:

Plain text:

Sonnentag, N. (2026). Open3DCP: Open Data Standard for 3D Concrete Printing [Schema]. Sunnyday Technologies. https://doi.org/10.5281/zenodo.19647471

BibTeX:

@misc{open3dcp_2026,
  author       = {Sonnentag, Nicholas},
  title        = {{Open3DCP: Open Data Standard for 3D Concrete Printing}},
  year         = {2026},
  publisher    = {Sunnyday Technologies},
  doi          = {10.5281/zenodo.19647471},
  url          = {https://open3dcp.org}
}

RIS:

TY  - DATA
T1  - Open3DCP: Open Data Standard for 3D Concrete Printing
AU  - Sonnentag, Nicholas
PY  - 2026
PB  - Sunnyday Technologies
DO  - 10.5281/zenodo.19647471
UR  - https://open3dcp.org
ER  -

A CITATION.cff file is included in the repository for automated citation tooling (Citation File Format v1.2.0).

References

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2. Hearley, B. L., and Arnold, S. M. (2023). NASA GRC ICME Schema for Materials Data Management: An Executive Summary. NASA/TM-20230018337. NASA Glenn Research Center.

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4. Reinhardt, H.-W., Wangler, T., and Roussel, N., eds. (2019). RILEM Technical Committee 304-ADC: State-of-the-art Report on Assessment of Additively Manufactured Concrete Materials and Structures. RILEM.

5. Sonnentag, N. (2026). Open3DCP: Open Data Standard for 3D Concrete Printing. Sunnyday Technologies. DOI: 10.5281/zenodo.19647471. https://github.com/sunnyday-technologies/Open3DCP

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Cross-references

• Schema reference and source: github.com/sunnyday-technologies/Open3DCP
• Canonical schema document: Open3DCP_SCHEMA.md
• Zenodo concept DOI: 10.5281/zenodo.19647471
• AI platform consuming Open3DCP-shaped data: CEMFORGE
• Hardware platform producing Open3DCP-shaped logs: M3-CRETE
• Validation tooling that consumes Open3DCP-shaped reports: CADCLAW
• Maintainer: Sunnyday Technologies