{ "dataset": { "name": "Concrete Crack Classification", "version": "1.0.0", "compiled_date": "2026-07-24", "last_verified": "2026-07-24", "canonical_page": "https://rockfordconcreteleveling.net/research/types-of-concrete-cracks/", "record_count": 48, "record_counts_by_level": { "mechanism": 24, "visual_descriptor": 13, "status_significance": 6, "related_condition": 5 }, "method_summary": "Source-traced editorial classification separating mechanism, visual descriptor, status/significance, and related condition. All consequential source claims were checked against issuing-organization materials on 2026-07-24." }, "sources": { "ACI_TOPIC": { "name": "American Concrete Institute — Cracking in Concrete topic page", "url": "https://www.concrete.org/topicsinconcrete/topicdetail.aspx?search=cracking+in+concrete", "edition": "accessed 2026-07-24" }, "ACI_CT25": { "name": "American Concrete Institute — ACI CT-25: 2025 ACI Concrete Terminology", "url": "https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf", "edition": "2025 edition; accessed 2026-07-24" }, "ACI_224R_PRODUCT": { "name": "American Concrete Institute — ACI PRC-224-01, Control of Cracking in Concrete Structures", "url": "https://www.concrete.org/store/productdetail.aspx?ItemID=22401&Format=DOWNLOAD&Language=English&Units=US_AND_METRIC", "edition": "publication year 2002; reapproved 2008; accessed 2026-07-24" }, "ACI_224R_CH3": { "name": "American Concrete Institute — ACI 224R-01, Chapter 3: Control of Cracking Due to Drying Shrinkage", "url": "https://www.concrete.org/Portals/0/Files/PDF/224R_01Ch3.pdf", "edition": "2001 edition; accessed 2026-07-24" }, "ACI_FAQ906": { "name": "American Concrete Institute — Frequently Asked Question: acceptable cracking", "url": "https://www.concrete.org/frequentlyaskedquestions.aspx?faqid=906", "edition": "accessed 2026-07-24" }, "ACI_SP319": { "name": "American Concrete Institute — SP-319 paper reproducing ACI 224R-01 Table 4.1", "url": "https://www.concrete.org/Portals/0/Files/PDF/Previews/SP-319_preview.pdf", "edition": "ACI Special Publication 319; accessed 2026-07-24" }, "ACI_2241": { "name": "American Concrete Institute — ACI PRC-224.1-07, Causes, Evaluation, and Repair of Cracks in Concrete Structures", "url": "https://www.concrete.org/publications/internationalconcreteabstractsportal.aspx?m=details&id=18555", "edition": "March 2007; accessed 2026-07-24" }, "NRMCA_CIP3": { "name": "National Ready Mixed Concrete Association — CIP 3, Crazing Concrete Surfaces", "url": "https://www.nrmca.org/wp-content/uploads/2021/01/03pr.pdf", "edition": "NRMCA-hosted edition; accessed 2026-07-24" }, "NRMCA_CIP4": { "name": "National Ready Mixed Concrete Association — CIP 4, Cracking Concrete Surfaces", "url": "https://www.nrmca.org/wp-content/uploads/2021/01/04pr.pdf", "edition": "NRMCA-hosted edition; accessed 2026-07-24" }, "NRMCA_CIP5": { "name": "National Ready Mixed Concrete Association — CIP 5, Plastic Shrinkage Cracking", "url": "https://www.nrmca.org/wp-content/uploads/2021/01/05pr.pdf", "edition": "NRMCA-hosted edition; accessed 2026-07-24" }, "NRMCA_CIP6": { "name": "National Ready Mixed Concrete Association — CIP 6, Joints in Concrete Slabs on Grade", "url": "https://www.nrmca.org/wp-content/uploads/2021/01/06pr.pdf", "edition": "NRMCA-hosted edition; accessed 2026-07-24" }, "NRMCA_CIP7": { "name": "National Ready Mixed Concrete Association — CIP 7, Cracks in Residential Basement Walls", "url": "https://www.nrmca.org/wp-content/uploads/2021/01/07pr.pdf", "edition": "2014 revision; accessed 2026-07-24" }, "NRMCA_CIP42": { "name": "National Ready Mixed Concrete Association — CIP 42, Thermal Cracking of Concrete", "url": "https://www.nrmca.org/wp-content/uploads/2021/09/42pr.pdf", "edition": "2009 edition; accessed 2026-07-24" }, "NRMCA_TIP17": { "name": "National Ready Mixed Concrete Association — TIP 17, Drying Shrinkage of Concrete", "url": "https://www.nrmca.org/wp-content/uploads/2020/04/TIP17w.pdf", "edition": "NRMCA-hosted edition; accessed 2026-07-24" }, "FHWA_LTPP": { "name": "Federal Highway Administration — Distress Identification Manual for the Long-Term Pavement Performance Program, Fifth Revised Edition", "url": "https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/ltpp/13092/13092.pdf", "edition": "FHWA-HRT-13-092, May 2014; accessed 2026-07-24" }, "FHWA_D67": { "name": "Federal Highway Administration — LTPP Directive D-67, Errata to FHWA-HRT-13-092", "url": "https://infopave.fhwa.dot.gov/InfoPave_Repository/Reports/B10/B10_20/D-67.pdf", "edition": "July 17, 2019; accessed 2026-07-24" }, "FHWA_HIF15018": { "name": "Federal Highway Administration — Materials-Related Distress: Hardened Cement Paste", "url": "https://www.fhwa.dot.gov/pavement/concrete/pubs/hif15018.pdf", "edition": "FHWA-HIF-15-018, June 2015; accessed 2026-07-24" }, "FHWA_HIF16033": { "name": "Federal Highway Administration — Ensuring Durability of Concrete Paving Mixtures, Part I: Mechanisms and Mitigation", "url": "https://www.fhwa.dot.gov/pavement/pubs/hif16033.pdf", "edition": "FHWA-HIF-16-033, April 2016; accessed 2026-07-24" }, "FHWA_RD01163": { "name": "Federal Highway Administration — Guidelines for Detection, Analysis, and Treatment of Materials-Related Distress in Concrete Pavements, Volume 1", "url": "https://highways.dot.gov/sites/fhwa.dot.gov/files/FHWA-RD-01-163.pdf", "edition": "FHWA-RD-01-163, March 2002; accessed 2026-07-24" }, "FHWA_RD01164": { "name": "Federal Highway Administration — Guidelines for Detection, Analysis, and Treatment of Materials-Related Distress in Concrete Pavements, Volume 2", "url": "https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/pccp/01164/sect1a.cfm", "edition": "FHWA-RD-01-164, March 2002; accessed 2026-07-24" }, "FHWA_SUPPORT": { "name": "Federal Highway Administration — Concrete Pavement Performance and Support Conditions", "url": "https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/pccp/04122/04.cfm", "edition": "FHWA research publication; accessed 2026-07-24" }, "FHWA_PRESERVATION": { "name": "Federal Highway Administration — Concrete Pavement Preservation Guide", "url": "https://www.fhwa.dot.gov/pavement/pubs/hif18025.pdf", "edition": "FHWA-HIF-18-025; accessed 2026-07-24" }, "NWS_ROCKFORD": { "name": "National Weather Service Chicago — Rockford 1991–2020 Climate Normals", "url": "https://www.weather.gov/lot/rockford_normals", "edition": "1991–2020 normals; accessed 2026-07-24" }, "ROCKFORD_CODES": { "name": "City of Rockford — Building Codes and Ordinances", "url": "https://rockfordil.gov/383/Building-Codes-Ordinances", "edition": "accessed 2026-07-24" }, "ROCKFORD_AMENDMENTS": { "name": "City of Rockford — Local Amendments to the 2021 International Building Code", "url": "https://www.rockfordil.gov/DocumentCenter/View/4455/Local-Amendments-to-2021-International-Building-Code-PDF", "edition": "effective for permits submitted on or after January 1, 2025; accessed 2026-07-24" }, "IDOT_AGGREGATE": { "name": "Illinois Department of Transportation — Aggregate material approvals and testing", "url": "https://idot.illinois.gov/doing-business/materials-marketplace/aggregate.html", "edition": "accessed 2026-07-24" }, "IDOT_CONCRETE": { "name": "Illinois Department of Transportation — Concrete materials testing", "url": "https://idot.illinois.gov/doing-business/materials-marketplace/concrete.html", "edition": "accessed 2026-07-24" } }, "records": [ { "record_id": "M01", "level": "mechanism", "family": "Before hardening", "name": "Plastic shrinkage cracking", "stage": "Fresh/plastic concrete", "physical_description": "Surface cracking that forms when moisture leaves fresh concrete faster than bleed water replaces it before set.", "visual_clues": "Usually shallow, mostly on horizontal surfaces, commonly parallel and about 1–3 ft apart; generally does not intersect the slab perimeter.", "standards_designation": "NRMCA CIP 5; ACI broad cause family: plastic shrinkage", "documented_time_of_appearance": "Hours, while concrete remains plastic", "what_it_does_not_establish": "The pattern is characteristic but not conclusive; distinguish it from plastic settlement, form movement, early thermal cracking, and section-depth changes.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "NRMCA_CIP5 | ACI_TOPIC", "primary_source_urls": "https://www.nrmca.org/wp-content/uploads/2021/01/05pr.pdf | https://www.concrete.org/topicsinconcrete/topicdetail.aspx?search=cracking+in+concrete", "source_edition_or_date": "NRMCA-hosted edition; accessed 2026-07-24 | accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M02", "level": "mechanism", "family": "Before hardening", "name": "Plastic settlement cracking over reinforcement", "stage": "Fresh/plastic concrete", "physical_description": "Fresh concrete continues to settle while reinforcing steel or another embedded item locally restrains that movement.", "visual_clues": "Cracks may trace the line of reinforcing bars or embedded obstructions.", "standards_designation": "NRMCA CIP 5", "documented_time_of_appearance": "Before hardening", "what_it_does_not_establish": "A crack aligned with reinforcement in hardened concrete can also accompany corrosion; timing and condition evidence matter.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "NRMCA_CIP5", "primary_source_urls": "https://www.nrmca.org/wp-content/uploads/2021/01/05pr.pdf", "source_edition_or_date": "NRMCA-hosted edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M03", "level": "mechanism", "family": "Before hardening", "name": "Formwork movement before hardening", "stage": "Fresh concrete to early strength gain", "physical_description": "Forms or supports move before concrete has developed enough strength to tolerate the displacement.", "visual_clues": "Irregular cracking or settlement tied to moved form lines, unsupported areas, or displaced geometry.", "standards_designation": "NRMCA CIP 5; NRMCA CIP 7", "documented_time_of_appearance": "Before hardening or adequate self-supporting strength", "what_it_does_not_establish": "Appearance alone cannot prove form movement; construction records and geometry are needed.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "NRMCA_CIP5 | NRMCA_CIP7", "primary_source_urls": "https://www.nrmca.org/wp-content/uploads/2021/01/05pr.pdf | https://www.nrmca.org/wp-content/uploads/2021/01/07pr.pdf", "source_edition_or_date": "NRMCA-hosted edition; accessed 2026-07-24 | 2014 revision; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M04", "level": "mechanism", "family": "Volume change", "name": "Drying shrinkage", "stage": "Hardened concrete", "physical_description": "Moisture loss causes hardened concrete to contract; restraint creates tensile stress and cracking.", "visual_clues": "Random, transverse, re-entrant, or joint-related cracks depending on geometry and restraint.", "standards_designation": "NRMCA TIP 17; ACI 224R-01 Chapter 3", "documented_time_of_appearance": "Typically evident within days to several weeks; later movement can continue", "what_it_does_not_establish": "“Shrinkage crack” identifies a mechanism, not a guaranteed depth, activity, or severity.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "NRMCA_TIP17 | ACI_224R_CH3", "primary_source_urls": "https://www.nrmca.org/wp-content/uploads/2020/04/TIP17w.pdf | https://www.concrete.org/Portals/0/Files/PDF/224R_01Ch3.pdf", "source_edition_or_date": "NRMCA-hosted edition; accessed 2026-07-24 | 2001 edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M05", "level": "mechanism", "family": "Volume change", "name": "Autogenous shrinkage", "stage": "Very early age to hardened concrete", "physical_description": "Internal hydration processes reduce volume without external moisture loss; the effect is more significant in low-w/cm mixtures.", "visual_clues": "No unique visible pattern; appears as restrained shrinkage cracking.", "standards_designation": "NRMCA TIP 17; ACI CT-25 autogenous volume change", "documented_time_of_appearance": "Most occurs during the first 24 hours; magnitude is small for most mixtures", "what_it_does_not_establish": "A visible crack cannot separate autogenous shrinkage from drying or thermal effects without mixture, timing, and exposure data.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "NRMCA_TIP17 | ACI_CT25", "primary_source_urls": "https://www.nrmca.org/wp-content/uploads/2020/04/TIP17w.pdf | https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf", "source_edition_or_date": "NRMCA-hosted edition; accessed 2026-07-24 | 2025 edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M06", "level": "mechanism", "family": "Volume change", "name": "Carbonation shrinkage", "stage": "Exposed hardened concrete", "physical_description": "Exposed hardened concrete reacts with atmospheric carbon dioxide and undergoes shrinkage.", "visual_clues": "No uniquely diagnostic pattern; may contribute to surface-zone shrinkage.", "standards_designation": "NRMCA TIP 17; ACI 224R-01 Chapter 3; ACI CT-25", "documented_time_of_appearance": "Long-term; no fixed appearance window in the reviewed sources", "what_it_does_not_establish": "Surface cracking alone cannot isolate carbonation shrinkage from other volume-change mechanisms.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "NRMCA_TIP17 | ACI_224R_CH3 | ACI_CT25", "primary_source_urls": "https://www.nrmca.org/wp-content/uploads/2020/04/TIP17w.pdf | https://www.concrete.org/Portals/0/Files/PDF/224R_01Ch3.pdf | https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf", "source_edition_or_date": "NRMCA-hosted edition; accessed 2026-07-24 | 2001 edition; accessed 2026-07-24 | 2025 edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M07", "level": "mechanism", "family": "Temperature", "name": "Thermal-gradient or restrained temperature cracking", "stage": "Early age or later service", "physical_description": "Temperature differences or restrained thermal expansion and contraction create tensile stress greater than the concrete can carry.", "visual_clues": "Random or patchwork surface cracks in thick members; slab and pavement cracks can resemble drying-shrinkage cracks and often run perpendicular to the long axis.", "standards_designation": "NRMCA CIP 42; ACI CT-25 temperature cracking", "documented_time_of_appearance": "Often early age; slab and pavement cracks usually within the first year or first summer–winter cycle", "what_it_does_not_establish": "Orientation is application-dependent; temperature history and restraint must be evaluated.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "NRMCA_CIP42 | ACI_CT25", "primary_source_urls": "https://www.nrmca.org/wp-content/uploads/2021/09/42pr.pdf | https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf", "source_edition_or_date": "2009 edition; accessed 2026-07-24 | 2025 edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M08", "level": "mechanism", "family": "Surface volume change", "name": "Crazing", "stage": "Early hardened surface", "physical_description": "Shrinkage of a paste-rich surface layer produces a fine random network of shallow cracks.", "visual_clues": "Small irregular cells; cracks rarely deeper than 1/8 in. (3 mm) and cells generally no more than 1.5 in. (40 mm) across.", "standards_designation": "NRMCA CIP 3; ACI CT-25", "documented_time_of_appearance": "Usually apparent the day after placement or by the end of the first week", "what_it_does_not_establish": "Not every map-like network is shallow crazing; deeper map cracking has other possible mechanisms.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "NRMCA_CIP3 | ACI_CT25", "primary_source_urls": "https://www.nrmca.org/wp-content/uploads/2021/01/03pr.pdf | https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf", "source_edition_or_date": "NRMCA-hosted edition; accessed 2026-07-24 | 2025 edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M09", "level": "mechanism", "family": "Restraint and jointing", "name": "Restraint from missing, late, or ineffective jointing", "stage": "Hardened concrete", "physical_description": "Expected shrinkage or temperature movement is restrained because contraction or isolation provisions are missing, late, or ineffective.", "visual_clues": "Random cracks where intended joints did not activate, or cracking where slabs are restrained by adjoining elements.", "standards_designation": "NRMCA CIP 4; NRMCA CIP 6; ACI 224R-01 Chapter 3", "documented_time_of_appearance": "No fixed appearance window; often becomes evident as drying or temperature movement develops", "what_it_does_not_establish": "The location suggests restraint but does not establish the only contributing mechanism.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "NRMCA_CIP4 | NRMCA_CIP6 | ACI_224R_CH3", "primary_source_urls": "https://www.nrmca.org/wp-content/uploads/2021/01/04pr.pdf | https://www.nrmca.org/wp-content/uploads/2021/01/06pr.pdf | https://www.concrete.org/Portals/0/Files/PDF/224R_01Ch3.pdf", "source_edition_or_date": "NRMCA-hosted edition; accessed 2026-07-24 | NRMCA-hosted edition; accessed 2026-07-24 | 2001 edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M10", "level": "mechanism", "family": "Geometry and restraint", "name": "Re-entrant corner cracking", "stage": "Hardened concrete", "physical_description": "Shrinkage or other restrained movement concentrates stress at an inward-pointing corner or opening.", "visual_clues": "A crack runs diagonally outward from a window, door, opening, drain, or other re-entrant corner.", "standards_designation": "NRMCA CIP 7; NRMCA CIP 6", "documented_time_of_appearance": "No fixed appearance window in the reviewed sources", "what_it_does_not_establish": "The geometry is a stress concentrator; it does not by itself establish structural significance.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "NRMCA_CIP7 | NRMCA_CIP6", "primary_source_urls": "https://www.nrmca.org/wp-content/uploads/2021/01/07pr.pdf | https://www.nrmca.org/wp-content/uploads/2021/01/06pr.pdf", "source_edition_or_date": "2014 revision; accessed 2026-07-24 | NRMCA-hosted edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M11", "level": "mechanism", "family": "Support movement", "name": "Differential support settlement", "stage": "In service", "physical_description": "The support beneath a slab, footing, pavement, or member settles nonuniformly.", "visual_clues": "Irregular cracking, faulting, rotation, or vertical offset across the crack.", "standards_designation": "NRMCA CIP 4; NRMCA CIP 7; FHWA LTPP faulting context", "documented_time_of_appearance": "No fixed appearance window in the reviewed sources", "what_it_does_not_establish": "A visible offset shows differential movement but not the exact subsurface cause.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "NRMCA_CIP4 | NRMCA_CIP7 | FHWA_LTPP", "primary_source_urls": "https://www.nrmca.org/wp-content/uploads/2021/01/04pr.pdf | https://www.nrmca.org/wp-content/uploads/2021/01/07pr.pdf | https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/ltpp/13092/13092.pdf", "source_edition_or_date": "NRMCA-hosted edition; accessed 2026-07-24 | 2014 revision; accessed 2026-07-24 | FHWA-HRT-13-092, May 2014; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M12", "level": "mechanism", "family": "Support movement", "name": "Loss of support from pumping or subgrade erosion", "stage": "In service", "physical_description": "Water and fine support material are ejected through joints or cracks, eroding support and increasing slab movement and cracking risk.", "visual_clues": "Water or fines at cracks and joints, staining, faulting, and cracking associated with support loss.", "standards_designation": "FHWA LTPP water bleeding and pumping; FHWA concrete pavement preservation guidance", "documented_time_of_appearance": "No fixed appearance window in the reviewed sources", "what_it_does_not_establish": "Surface deposits indicate pumping context but do not quantify the size or location of the support void.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "FHWA_LTPP | FHWA_PRESERVATION", "primary_source_urls": "https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/ltpp/13092/13092.pdf | https://www.fhwa.dot.gov/pavement/pubs/hif18025.pdf", "source_edition_or_date": "FHWA-HRT-13-092, May 2014; accessed 2026-07-24 | FHWA-HIF-18-025; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M13", "level": "mechanism", "family": "Support movement", "name": "Frost heave or thaw-softened support movement", "stage": "Seasonal service", "physical_description": "Frost-susceptible support heaves during freezing or loses stiffness and support during thaw.", "visual_clues": "Seasonal lifting, settlement, faulting, or cracking that changes with support conditions.", "standards_designation": "FHWA support-condition research", "documented_time_of_appearance": "Seasonal; no universal year-of-appearance range", "what_it_does_not_establish": "Air temperature alone does not establish subsurface freezing, moisture, soil susceptibility, or damage.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "FHWA_SUPPORT", "primary_source_urls": "https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/pccp/04122/04.cfm", "source_edition_or_date": "FHWA research publication; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M14", "level": "mechanism", "family": "Support movement", "name": "Expansive-soil movement", "stage": "In service", "physical_description": "Moisture-sensitive soils shrink or swell nonuniformly beneath concrete.", "visual_clues": "Nonuniform lifting, settlement, rotation, or cracking tied to changing support.", "standards_designation": "NRMCA CIP 4; NRMCA CIP 7", "documented_time_of_appearance": "No fixed appearance window in the reviewed sources", "what_it_does_not_establish": "The crack pattern cannot identify soil mineralogy or moisture conditions without site evidence.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "NRMCA_CIP4 | NRMCA_CIP7", "primary_source_urls": "https://www.nrmca.org/wp-content/uploads/2021/01/04pr.pdf | https://www.nrmca.org/wp-content/uploads/2021/01/07pr.pdf", "source_edition_or_date": "NRMCA-hosted edition; accessed 2026-07-24 | 2014 revision; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M15", "level": "mechanism", "family": "Durability and corrosion", "name": "Reinforcement-corrosion expansion cracking", "stage": "Hardened reinforced concrete", "physical_description": "Corrosion products expand around embedded steel, creating tensile stress that can crack, delaminate, or spall the cover concrete.", "visual_clues": "Cracks or spalls aligned with reinforcing steel, rust staining, exposed reinforcement, or delamination.", "standards_designation": "ACI cracking cause family: corrosion; ACI CT-25; FHWA materials-related distress", "documented_time_of_appearance": "FHWA 2016: 3–20 years; FHWA 2015: 3–10 years", "what_it_does_not_establish": "A rebar-aligned crack can also originate as plastic settlement; timing, corrosion evidence, and testing distinguish them.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_TOPIC | ACI_CT25 | FHWA_HIF16033 | FHWA_HIF15018", "primary_source_urls": "https://www.concrete.org/topicsinconcrete/topicdetail.aspx?search=cracking+in+concrete | https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf | https://www.fhwa.dot.gov/pavement/pubs/hif16033.pdf | https://www.fhwa.dot.gov/pavement/concrete/pubs/hif15018.pdf", "source_edition_or_date": "accessed 2026-07-24 | 2025 edition; accessed 2026-07-24 | FHWA-HIF-16-033, April 2016; accessed 2026-07-24 | FHWA-HIF-15-018, June 2015; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M16", "level": "mechanism", "family": "Loading", "name": "Externally applied load", "stage": "In service", "physical_description": "Applied loading produces tensile or shear stresses beyond the element’s capacity or current condition.", "visual_clues": "Pattern depends on the element: corner breaks, flexural cracks, diagonal cracks, or cracking around load paths.", "standards_designation": "ACI broad cause family: externally applied loads; FHWA LTPP corner breaks", "documented_time_of_appearance": "Under or after loading; no universal age window", "what_it_does_not_establish": "A visible pattern does not establish load magnitude or remaining capacity.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_TOPIC | FHWA_LTPP", "primary_source_urls": "https://www.concrete.org/topicsinconcrete/topicdetail.aspx?search=cracking+in+concrete | https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/ltpp/13092/13092.pdf", "source_edition_or_date": "accessed 2026-07-24 | FHWA-HRT-13-092, May 2014; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M17", "level": "mechanism", "family": "Loading", "name": "Construction overload", "stage": "Early age or construction stage", "physical_description": "Temporary construction loads are applied before concrete has developed adequate strength or support.", "visual_clues": "Permanent cracking tied to construction sequencing or temporary loading.", "standards_designation": "ACI broad cause family: construction overloads", "documented_time_of_appearance": "During construction or early strength gain", "what_it_does_not_establish": "Timing and project load history are required; appearance alone cannot prove overload.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_TOPIC", "primary_source_urls": "https://www.concrete.org/topicsinconcrete/topicdetail.aspx?search=cracking+in+concrete", "source_edition_or_date": "accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M18", "level": "mechanism", "family": "Loading", "name": "Shear or diagonal-tension cracking", "stage": "Structural service", "physical_description": "Combined normal and shear stresses produce inclined principal tensile stress and diagonal cracking.", "visual_clues": "Inclined cracks in a structural member; ACI notes approximately 45 degrees in a flexural-member context.", "standards_designation": "ACI CT-25 diagonal crack and diagonal tension", "documented_time_of_appearance": "Under load; no universal age window", "what_it_does_not_establish": "Not every diagonal crack is shear-related; slabs can have diagonal cracks defined only by geometry.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_CT25", "primary_source_urls": "https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf", "source_edition_or_date": "2025 edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M19", "level": "mechanism", "family": "Durability", "name": "Freeze-thaw deterioration of hardened cement paste", "stage": "Hardened concrete", "physical_description": "Critically saturated cement paste undergoes repeated freezing and thawing without adequate protection from its air-void system.", "visual_clues": "Scaling, spalling, or map cracking, often initiating near joints or cracks in pavement contexts.", "standards_designation": "FHWA materials-related distress", "documented_time_of_appearance": "FHWA 2016: 1–10 years; FHWA 2015: 1–5 years", "what_it_does_not_establish": "Air-temperature crossings do not measure saturation, concrete temperature, or material cycles.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "FHWA_HIF16033 | FHWA_HIF15018", "primary_source_urls": "https://www.fhwa.dot.gov/pavement/pubs/hif16033.pdf | https://www.fhwa.dot.gov/pavement/concrete/pubs/hif15018.pdf", "source_edition_or_date": "FHWA-HIF-16-033, April 2016; accessed 2026-07-24 | FHWA-HIF-15-018, June 2015; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M20", "level": "mechanism", "family": "Durability", "name": "Deicer scaling and deterioration", "stage": "Hardened surface", "physical_description": "Deicing exposure contributes to near-surface deterioration in susceptible concrete.", "visual_clues": "Scaling or crazing of the slab surface, with staining at joints or cracks in FHWA pavement guidance.", "standards_designation": "FHWA materials-related distress", "documented_time_of_appearance": "1–5 years in both FHWA 2015 and 2016 tables", "what_it_does_not_establish": "Scaling is a separate deterioration condition; its presence does not identify the full underlying mechanism by itself.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "FHWA_HIF16033 | FHWA_HIF15018", "primary_source_urls": "https://www.fhwa.dot.gov/pavement/pubs/hif16033.pdf | https://www.fhwa.dot.gov/pavement/concrete/pubs/hif15018.pdf", "source_edition_or_date": "FHWA-HIF-16-033, April 2016; accessed 2026-07-24 | FHWA-HIF-15-018, June 2015; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M21", "level": "mechanism", "family": "Durability", "name": "Freeze-thaw deterioration of susceptible aggregate (D-cracking)", "stage": "Hardened concrete", "physical_description": "Susceptible coarse aggregate deteriorates under freezing and thawing.", "visual_clues": "Closely spaced crescent-shaped hairline cracking beside joints, cracks, or free edges, commonly initiating at slab corners; later loose or missing material.", "standards_designation": "FHWA materials-related distress; FHWA LTPP JCP 2", "documented_time_of_appearance": "FHWA 2016: 10–25 years; FHWA 2015: 10–15 years", "what_it_does_not_establish": "The characteristic field pattern supports screening but does not replace aggregate evidence or petrographic evaluation.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "FHWA_HIF16033 | FHWA_HIF15018 | FHWA_LTPP", "primary_source_urls": "https://www.fhwa.dot.gov/pavement/pubs/hif16033.pdf | https://www.fhwa.dot.gov/pavement/concrete/pubs/hif15018.pdf | https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/ltpp/13092/13092.pdf", "source_edition_or_date": "FHWA-HIF-16-033, April 2016; accessed 2026-07-24 | FHWA-HIF-15-018, June 2015; accessed 2026-07-24 | FHWA-HRT-13-092, May 2014; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M22", "level": "mechanism", "family": "Durability and chemical reaction", "name": "Alkali-silica reactivity (ASR)", "stage": "Hardened concrete", "physical_description": "Alkalis react with susceptible siliceous aggregate, producing expansive reaction products and cracking.", "visual_clues": "Map cracking across the slab surface, joint closure, spalling, or blowups in pavement guidance.", "standards_designation": "FHWA materials-related distress", "documented_time_of_appearance": "FHWA 2016: 5–25 years; FHWA 2015: 5–15 years", "what_it_does_not_establish": "Map cracking is not unique to ASR; field appearance alone does not distinguish ASR from ACR or other mechanisms.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "FHWA_HIF16033 | FHWA_HIF15018 | FHWA_RD01164", "primary_source_urls": "https://www.fhwa.dot.gov/pavement/pubs/hif16033.pdf | https://www.fhwa.dot.gov/pavement/concrete/pubs/hif15018.pdf | https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/pccp/01164/sect1a.cfm", "source_edition_or_date": "FHWA-HIF-16-033, April 2016; accessed 2026-07-24 | FHWA-HIF-15-018, June 2015; accessed 2026-07-24 | FHWA-RD-01-164, March 2002; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M23", "level": "mechanism", "family": "Durability and chemical reaction", "name": "Alkali-carbonate reactivity (ACR)", "stage": "Hardened concrete", "physical_description": "Alkalis react with susceptible carbonate aggregate, producing expansion and cracking.", "visual_clues": "Map cracking across the slab surface, spalling, or blowups in pavement guidance.", "standards_designation": "FHWA materials-related distress", "documented_time_of_appearance": "5–15 years in both FHWA 2015 and 2016 tables", "what_it_does_not_establish": "Field appearance alone generally cannot separate ACR from ASR; petrographic and material evidence are needed.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "FHWA_HIF16033 | FHWA_HIF15018 | FHWA_RD01164", "primary_source_urls": "https://www.fhwa.dot.gov/pavement/pubs/hif16033.pdf | https://www.fhwa.dot.gov/pavement/concrete/pubs/hif15018.pdf | https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/pccp/01164/sect1a.cfm", "source_edition_or_date": "FHWA-HIF-16-033, April 2016; accessed 2026-07-24 | FHWA-HIF-15-018, June 2015; accessed 2026-07-24 | FHWA-RD-01-164, March 2002; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "M24", "level": "mechanism", "family": "Durability and chemical reaction", "name": "Sulfate attack, external or internal", "stage": "Hardened concrete", "physical_description": "Sulfate-related chemical or physical processes damage concrete or mortar and can produce expansion and cracking.", "visual_clues": "Fine cracking near joints or slab edges, or map cracking over the slab surface, depending on the mechanism.", "standards_designation": "FHWA materials-related distress; ACI CT-25 delayed ettringite formation", "documented_time_of_appearance": "External: FHWA 2016 1–10 years versus 2015 1–5; internal: 1–5 years in both", "what_it_does_not_establish": "Map cracking is not unique to sulfate attack; exposure history and testing are required.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "FHWA_HIF16033 | FHWA_HIF15018 | ACI_CT25", "primary_source_urls": "https://www.fhwa.dot.gov/pavement/pubs/hif16033.pdf | https://www.fhwa.dot.gov/pavement/concrete/pubs/hif15018.pdf | https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf", "source_edition_or_date": "FHWA-HIF-16-033, April 2016; accessed 2026-07-24 | FHWA-HIF-15-018, June 2015; accessed 2026-07-24 | 2025 edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "V01", "level": "visual_descriptor", "family": "Width and visibility", "name": "Hairline", "stage": "Any visible stage", "physical_description": "A concrete surface crack with a width so small as to be barely perceptible.", "visual_clues": "A very fine visible line.", "standards_designation": "ACI CT-25 hairline crack", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "Cause, depth, activity, and structural or durability significance.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_CT25", "primary_source_urls": "https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf", "source_edition_or_date": "2025 edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "V02", "level": "visual_descriptor", "family": "Pattern", "name": "Checking", "stage": "Surface condition", "physical_description": "Shallow cracks at closely spaced but irregular intervals on a concrete, mortar, cement-paste, or plaster surface.", "visual_clues": "A fine, closely spaced surface network.", "standards_designation": "ACI CT-25 checking", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "Whether cracking extends below the surface or which mechanism caused it.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_CT25", "primary_source_urls": "https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf", "source_edition_or_date": "2025 edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "V03", "level": "visual_descriptor", "family": "Pattern", "name": "Craze pattern", "stage": "Surface condition", "physical_description": "Fine random cracks or fissures in a surface; crazing is the development or existing pattern of those craze cracks.", "visual_clues": "Small, irregular interconnected cells.", "standards_designation": "ACI CT-25 craze cracks and crazing; NRMCA CIP 3", "documented_time_of_appearance": "Usually visible day 1 through week 1 when caused by surface crazing", "what_it_does_not_establish": "That every network pattern is shallow or cosmetic.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_CT25 | NRMCA_CIP3", "primary_source_urls": "https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf | https://www.nrmca.org/wp-content/uploads/2021/01/03pr.pdf", "source_edition_or_date": "2025 edition; accessed 2026-07-24 | NRMCA-hosted edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "V04", "level": "visual_descriptor", "family": "Pattern", "name": "Map or pattern cracking", "stage": "Hardened concrete", "physical_description": "Intersecting cracks extending below the surface of hardened concrete, varying from fine and barely visible to open and well-defined.", "visual_clues": "An interconnected map-like network.", "standards_designation": "ACI CT-25 map cracking; FHWA LTPP JCP 8a", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "Which mechanism produced the network; several mechanisms can create similar patterns.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_CT25 | FHWA_LTPP", "primary_source_urls": "https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf | https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/ltpp/13092/13092.pdf", "source_edition_or_date": "2025 edition; accessed 2026-07-24 | FHWA-HRT-13-092, May 2014; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "V05", "level": "visual_descriptor", "family": "Pattern", "name": "Random", "stage": "Any visible stage", "physical_description": "Cracks running in varying directions without a regular orientation.", "visual_clues": "Irregular direction and spacing.", "standards_designation": "Editorial geometry label supported by NRMCA random-pattern descriptions", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "Whether shrinkage, restraint, thermal effects, support movement, or another mechanism dominated.", "classification_basis": "Editorial descriptor grounded in primary-source usage", "primary_source_ids": "NRMCA_CIP3 | NRMCA_CIP4 | NRMCA_CIP42", "primary_source_urls": "https://www.nrmca.org/wp-content/uploads/2021/01/03pr.pdf | https://www.nrmca.org/wp-content/uploads/2021/01/04pr.pdf | https://www.nrmca.org/wp-content/uploads/2021/09/42pr.pdf", "source_edition_or_date": "NRMCA-hosted edition; accessed 2026-07-24 | NRMCA-hosted edition; accessed 2026-07-24 | 2009 edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "V06", "level": "visual_descriptor", "family": "Pattern", "name": "Parallel or regularly spaced", "stage": "Fresh or hardened surface", "physical_description": "Cracks with broadly consistent direction and spacing.", "visual_clues": "Repeated near-parallel lines; plastic-shrinkage cracks are commonly about 1–3 ft apart.", "standards_designation": "NRMCA CIP 5", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "Cause by itself; timing and context are still required.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "NRMCA_CIP5", "primary_source_urls": "https://www.nrmca.org/wp-content/uploads/2021/01/05pr.pdf", "source_edition_or_date": "NRMCA-hosted edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "V07", "level": "visual_descriptor", "family": "Orientation", "name": "Vertical", "stage": "Visible wall or member", "physical_description": "A crack whose visible path is predominantly vertical in the chosen reference frame.", "visual_clues": "Mostly up-and-down orientation.", "standards_designation": "Editorial orientation label; examples appear in NRMCA CIP 7", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "Cause, activity, displacement, or consequence.", "classification_basis": "Editorial geometry label", "primary_source_ids": "NRMCA_CIP7", "primary_source_urls": "https://www.nrmca.org/wp-content/uploads/2021/01/07pr.pdf", "source_edition_or_date": "2014 revision; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "V08", "level": "visual_descriptor", "family": "Orientation", "name": "Horizontal", "stage": "Visible wall or member", "physical_description": "A crack whose visible path is predominantly horizontal in the chosen reference frame.", "visual_clues": "Mostly side-to-side orientation.", "standards_designation": "Editorial orientation label", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "Whether lateral load, restraint, corrosion, or another cause is involved.", "classification_basis": "Editorial geometry label", "primary_source_ids": "ACI_TOPIC", "primary_source_urls": "https://www.concrete.org/topicsinconcrete/topicdetail.aspx?search=cracking+in+concrete", "source_edition_or_date": "accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "V09", "level": "visual_descriptor", "family": "Orientation", "name": "Diagonal", "stage": "Slab or structural member", "physical_description": "In a flexural member, an inclined crack associated with shear stress; in a slab, a crack not parallel to lateral or longitudinal directions.", "visual_clues": "An inclined path.", "standards_designation": "ACI CT-25 diagonal crack", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "That every diagonal crack is structural or shear-related.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_CT25", "primary_source_urls": "https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf", "source_edition_or_date": "2025 edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "V10", "level": "visual_descriptor", "family": "Orientation", "name": "Longitudinal", "stage": "Member or pavement", "physical_description": "A crack generally parallel to a member’s length or pavement centerline.", "visual_clues": "Runs along the long axis or centerline.", "standards_designation": "ACI CT-25; FHWA LTPP JCP 3", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "Severity; FHWA severity also depends on width, spalling, and faulting within a pavement-specific system.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_CT25 | FHWA_LTPP", "primary_source_urls": "https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf | https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/ltpp/13092/13092.pdf", "source_edition_or_date": "2025 edition; accessed 2026-07-24 | FHWA-HRT-13-092, May 2014; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "V11", "level": "visual_descriptor", "family": "Orientation", "name": "Transverse", "stage": "Member or pavement", "physical_description": "A crack crossing the longer dimension or running predominantly perpendicular to a pavement centerline.", "visual_clues": "Crosses the long axis or centerline.", "standards_designation": "ACI CT-25; FHWA LTPP JCP 4", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "Severity outside the named application and measurement system.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_CT25 | FHWA_LTPP", "primary_source_urls": "https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf | https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/ltpp/13092/13092.pdf", "source_edition_or_date": "2025 edition; accessed 2026-07-24 | FHWA-HRT-13-092, May 2014; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "V12", "level": "visual_descriptor", "family": "Geometry", "name": "Re-entrant corner", "stage": "Wall, slab, or opening", "physical_description": "A crack beginning at or extending from an inward-pointing corner or opening.", "visual_clues": "Commonly runs diagonally from the corner of a window, door, drain, or opening.", "standards_designation": "NRMCA CIP 7; NRMCA CIP 6", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "Whether jointing, shrinkage, support movement, or loading was the dominant mechanism.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "NRMCA_CIP7 | NRMCA_CIP6", "primary_source_urls": "https://www.nrmca.org/wp-content/uploads/2021/01/07pr.pdf | https://www.nrmca.org/wp-content/uploads/2021/01/06pr.pdf", "source_edition_or_date": "2014 revision; accessed 2026-07-24 | NRMCA-hosted edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "V13", "level": "visual_descriptor", "family": "Pattern", "name": "Crescent-shaped at joints and edges", "stage": "Pavement surface", "physical_description": "A closely spaced crescent-shaped hairline pattern adjacent to joints, cracks, or free edges.", "visual_clues": "Crescents commonly initiating near slab corners.", "standards_designation": "FHWA LTPP JCP 2 D-cracking pattern", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "Confirmation of aggregate freeze-thaw deterioration without material evidence.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "FHWA_LTPP", "primary_source_urls": "https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/ltpp/13092/13092.pdf", "source_edition_or_date": "FHWA-HRT-13-092, May 2014; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "S01", "level": "status_significance", "family": "Activity", "name": "Active", "stage": "Observed over time", "physical_description": "A crack whose width changes with time.", "visual_clues": "Opening, closing, or measurable width change between observations.", "standards_designation": "ACI CT-25 active crack", "documented_time_of_appearance": "Requires observations over time", "what_it_does_not_establish": "Cause, safety, or severity by itself.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_CT25", "primary_source_urls": "https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf", "source_edition_or_date": "2025 edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "S02", "level": "status_significance", "family": "Activity", "name": "Dormant", "stage": "Observed over time", "physical_description": "A crack whose width does not change with time.", "visual_clues": "No measured width change over the observation period.", "standards_designation": "ACI CT-25 dormant crack", "documented_time_of_appearance": "Requires observations over time", "what_it_does_not_establish": "That the crack is harmless, shallow, or free of durability consequences.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_CT25", "primary_source_urls": "https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf", "source_edition_or_date": "2025 edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "S03", "level": "status_significance", "family": "Consequence", "name": "Appearance-only", "stage": "Assessed context", "physical_description": "Appearance is affected without evidence in that assessment of structural distress or durability loss.", "visual_clues": "Visible cracking with no other identified consequence in the assessed context.", "standards_designation": "ACI cracking consequence framework", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "A permanent conclusion without an appropriate assessment and observation period.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_TOPIC", "primary_source_urls": "https://www.concrete.org/topicsinconcrete/topicdetail.aspx?search=cracking+in+concrete", "source_edition_or_date": "accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "S04", "level": "status_significance", "family": "Consequence", "name": "Durability-related", "stage": "Assessed context", "physical_description": "The crack accompanies deterioration or creates a pathway relevant to moisture, chlorides, freezing, corrosion, or another exposure mechanism.", "visual_clues": "Cracking with leakage, corrosion, delamination, scaling, spalling, or other deterioration evidence.", "standards_designation": "ACI cracking consequence framework; ACI 224R-01 Chapter 3", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "Structural significance; durability and structural consequences are separate questions.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_TOPIC | ACI_224R_CH3", "primary_source_urls": "https://www.concrete.org/topicsinconcrete/topicdetail.aspx?search=cracking+in+concrete | https://www.concrete.org/Portals/0/Files/PDF/224R_01Ch3.pdf", "source_edition_or_date": "accessed 2026-07-24 | 2001 edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "S05", "level": "status_significance", "family": "Consequence", "name": "Structural", "stage": "Assessed context", "physical_description": "The crack is associated with strength, stability, load response, or the load path of the element.", "visual_clues": "Project-specific; may involve load-bearing members, displacement, or load-related patterns.", "standards_designation": "ACI cracking consequence framework", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "A conclusion from orientation or width alone.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_TOPIC", "primary_source_urls": "https://www.concrete.org/topicsinconcrete/topicdetail.aspx?search=cracking+in+concrete", "source_edition_or_date": "accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "S06", "level": "status_significance", "family": "Consequence", "name": "Serviceability-related", "stage": "Assessed context", "physical_description": "The crack affects intended use, leakage control, moisture resistance, deflection, or another service function.", "visual_clues": "Leakage, loss of watertightness, excessive movement, or impaired use.", "standards_designation": "ACI 224R-01 Chapter 3; NRMCA CIP 7", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "That the member has lost structural capacity.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_224R_CH3 | NRMCA_CIP7", "primary_source_urls": "https://www.concrete.org/Portals/0/Files/PDF/224R_01Ch3.pdf | https://www.nrmca.org/wp-content/uploads/2021/01/07pr.pdf", "source_edition_or_date": "2001 edition; accessed 2026-07-24 | 2014 revision; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "C01", "level": "related_condition", "family": "Separation", "name": "Delamination", "stage": "Hardened material", "physical_description": "A planar separation roughly parallel to the material surface.", "visual_clues": "Hollow or detached near-surface layer; cracking may outline the separated area.", "standards_designation": "ACI CT-25 delamination", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "A crack orientation or mechanism by itself.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_CT25", "primary_source_urls": "https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf", "source_edition_or_date": "2025 edition; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "C02", "level": "related_condition", "family": "Surface deterioration", "name": "Scaling", "stage": "Hardened surface", "physical_description": "Flaking or peeling away of the near-surface portion of hardened concrete or mortar.", "visual_clues": "Loss of surface mortar or shallow surface layers.", "standards_designation": "ACI CT-25 scaling; FHWA LTPP JCP 8b", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "A crack mechanism; scaling can accompany several exposure conditions.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_CT25 | FHWA_LTPP", "primary_source_urls": "https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf | https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/ltpp/13092/13092.pdf", "source_edition_or_date": "2025 edition; accessed 2026-07-24 | FHWA-HRT-13-092, May 2014; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "C03", "level": "related_condition", "family": "Material loss", "name": "Spalling", "stage": "Hardened material", "physical_description": "Development of fragments detached by impact, weather, pressure, or expansion within the larger mass.", "visual_clues": "Broken, chipped, or detached concrete at a surface, crack, joint, or reinforcement line.", "standards_designation": "ACI CT-25 spall and spalling; FHWA LTPP joint spalling", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "The initiating mechanism; corrosion, freeze-thaw, loading, and other causes can all produce spalls.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_CT25 | FHWA_LTPP | FHWA_D67", "primary_source_urls": "https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf | https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/ltpp/13092/13092.pdf | https://infopave.fhwa.dot.gov/InfoPave_Repository/Reports/B10/B10_20/D-67.pdf", "source_edition_or_date": "2025 edition; accessed 2026-07-24 | FHWA-HRT-13-092, May 2014; accessed 2026-07-24 | July 17, 2019; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "C04", "level": "related_condition", "family": "Localized material loss", "name": "Popout", "stage": "Hardened surface", "physical_description": "A small localized portion of a concrete surface breaks away, commonly leaving a shallow conical depression.", "visual_clues": "Small isolated pit or cone-shaped loss.", "standards_designation": "ACI CT-25 popout; FHWA LTPP JCP 10", "documented_time_of_appearance": "Not applicable", "what_it_does_not_establish": "A crack type or evidence of a broad structural failure.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "ACI_CT25 | FHWA_LTPP", "primary_source_urls": "https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf | https://www.fhwa.dot.gov/publications/research/infrastructure/pavements/ltpp/13092/13092.pdf", "source_edition_or_date": "2025 edition; accessed 2026-07-24 | FHWA-HRT-13-092, May 2014; accessed 2026-07-24", "verified_date": "2026-07-24" }, { "record_id": "C05", "level": "related_condition", "family": "Placement interface", "name": "Cold joint or pour line", "stage": "Between placements", "physical_description": "A visible interface between successive placements; a cold joint forms when the earlier placement has hardened enough that the two placements do not consolidate into a monolithic mass.", "visual_clues": "A straight or irregular line at a placement boundary.", "standards_designation": "NRMCA CIP 7 pour line and cold joint; ACI CT-25 construction-joint terminology", "documented_time_of_appearance": "Visible after placement; no universal crack-appearance window", "what_it_does_not_establish": "That the interface is open, active, leaking, or structurally deficient.", "classification_basis": "Primary-source term or mechanism", "primary_source_ids": "NRMCA_CIP7 | ACI_CT25", "primary_source_urls": "https://www.nrmca.org/wp-content/uploads/2021/01/07pr.pdf | https://www.concrete.org/portals/0/files/pdf/aci_concrete_terminology.pdf", "source_edition_or_date": "2014 revision; accessed 2026-07-24 | 2025 edition; accessed 2026-07-24", "verified_date": "2026-07-24" } ] }