diff --git a/20-agents/aeco/engineering/steel-detailer-us/manifest.yaml b/20-agents/aeco/engineering/steel-detailer-us/manifest.yaml index 2f217db6e..d9431902e 100644 --- a/20-agents/aeco/engineering/steel-detailer-us/manifest.yaml +++ b/20-agents/aeco/engineering/steel-detailer-us/manifest.yaml @@ -1,5 +1,5 @@ agent: steel-detailer-us -version: 0.2.0 +version: 0.3.0 sdk-target: aisc-360-22 # the code edition these rules are sourced from display-name: Steel Detailer — US (AISC) @@ -14,7 +14,7 @@ description: | ("no verified source") rather than guessing. Covers bolted + welded connection geometry and the governing limit states (edge distance, spacing, hole types, weld sizing, block shear), drawing & detailing conventions (AISC 303), - materials/sections, and a deterministic lookup command backed by a 66-rule + materials/sections, and a deterministic lookup command backed by a 70-rule verified JSON database. US/AISC only — never mix with Eurocode (that is the separate steel-detailer-uk agent). @@ -93,6 +93,7 @@ skills: - bolt-bearing-tearout.md - bolt-pretension-and-joint-types.md - bolt-washers.md + - bolt-length-and-grip.md - weld-fillet-sizing.md - weld-length-and-pjp.md - connecting-elements-block-shear.md diff --git a/20-agents/aeco/engineering/steel-detailer-us/rules/aisc-360-22.json b/20-agents/aeco/engineering/steel-detailer-us/rules/aisc-360-22.json index 36adcfaec..4f6432ff1 100644 --- a/20-agents/aeco/engineering/steel-detailer-us/rules/aisc-360-22.json +++ b/20-agents/aeco/engineering/steel-detailer-us/rules/aisc-360-22.json @@ -1,8 +1,8 @@ { "agent": "steel-detailer-us", "standard": "aisc-360-22", - "version": "1.0.0", - "last_verified": "2026-06-14", + "version": "1.1.0", + "last_verified": "2026-06-28", "sources": [ "AISC 360-22 (free — aisc.org/standards)", "RCSC 2020 (free — boltcouncil.org)", @@ -320,6 +320,46 @@ "source_quote": "The specified minimum pretensions … are based on 70 percent of the tensile strength … rounded to the nearest kip", "found": true }, + { + "id": "bolt.length.grip", + "category": "bolts", + "rule": "Grip (basis for bolt-length selection)", + "value": "Total thickness of the connected plies the bolt passes through, EXCLUDING washers and direct-tension indicators (DTIs)", + "units": "in.", + "citation": "RCSC 2020 Glossary (\"Grip\")", + "source_quote": "Grip. The total thickness of material a bolt passes through, exclusive of washers or direct-tension indicators.", + "found": true + }, + { + "id": "bolt.length.engagement", + "category": "bolts", + "rule": "Bolt length must achieve sufficient thread engagement", + "value": "Length chosen so the installed bolt end is at least flush with (or beyond) the outer face of the nut — develops the bolt's strength", + "units": "dimensionless", + "citation": "RCSC 2020 §2.7; Glossary (\"Sufficient Thread Engagement\")", + "source_quote": "The bolt length used shall be such that, when installed, sufficient thread engagement (as defined in the Glossary) is achieved. [Glossary:] … the available bolt threads extending beyond or at least flush with the outer face of the nut; a condition that develops the strength of the bolt.", + "found": true + }, + { + "id": "bolt.length.select", + "category": "bolts", + "rule": "Selecting bolt length from grip", + "value": "length = grip + add-to-grip value (RCSC Table C-2.2), rounded to nearest ¼ in. (½ in. for lengths over 6 in.)", + "units": "in.", + "citation": "RCSC 2020 Commentary §2.7, Table C-2.2 (more extensive: Carter 1996, AISC Engineering Journal 2Q)", + "source_quote": "To determine the required bolt length, the value shown in Table C-2.2 should be added to the grip … The length determined by the use of Table C-2.2 should be adjusted to the nearest ¼-in. increment (or ½-in. increment for lengths exceeding 6 in.). A more extensive table … is available (Carter, 1996).", + "found": true + }, + { + "id": "bolt.length.washer.add", + "category": "bolts", + "rule": "Washer thickness added to grip when selecting bolt length", + "value": "+5/32 in. per ASTM F436 flat washer; +5/16 in. per beveled washer (added to grip before length selection)", + "units": "in.", + "citation": "RCSC 2020 Commentary §2.7, Table C-2.2", + "source_quote": "For each ASTM F436 washer that is used, add 5/32 in.; for each beveled washer, add 5/16 in.", + "found": true + }, { "id": "weld.fillet.min.to.025in", "category": "welds", diff --git a/20-agents/aeco/engineering/steel-detailer-us/skills/bolt-length-and-grip.md b/20-agents/aeco/engineering/steel-detailer-us/skills/bolt-length-and-grip.md new file mode 100644 index 000000000..8e76a6d54 --- /dev/null +++ b/20-agents/aeco/engineering/steel-detailer-us/skills/bolt-length-and-grip.md @@ -0,0 +1,57 @@ +--- +name: steel-detailer-us-bolt-length-and-grip +description: Use for US high-strength bolt LENGTH selection — how long a bolt must be for a given grip (the clamped plies), the grip definition, the "sufficient thread engagement" requirement that sets length, adding washer thickness to grip, and where the add-to-grip length table lives. RCSC 2020 §2.7, Glossary, and Commentary Table C-2.2. +--- + +# Bolt length & grip (RCSC) + +A high-strength bolt must be **long enough to develop its strength** — i.e. long enough that, when +installed, it achieves **sufficient thread engagement** with the nut. Length is selected from the **grip**. + +- **Grip** = the **total thickness of the connected plies** the bolt passes through, **excluding washers + and direct-tension indicators (DTIs).** (`grip` is the clamped structural material only.) +- **The length requirement is normative (RCSC §2.7):** the bolt length used **shall** be such that, when + installed, **sufficient thread engagement** is achieved. *"Sufficient thread engagement"* = the end of + the bolt (excluding a spline-end's spline) is **at least flush with — or extends beyond — the outer face + of the nut**; the condition that develops the bolt's strength (Glossary). Too short → the threads do not + fully engage the nut; the joint cannot develop the bolt. +- **How length is selected (method):** required length = **grip + the add-to-grip value from RCSC + Table C-2.2**, then **rounded to the nearest ¼ in. (½ in. for lengths over 6 in.)**. The tabulated + add-to-grip values already provide for manufacturing tolerances and sufficient thread engagement. +- **Washers add to the grip *for length selection*** (even though washers are not part of the grip + itself): add **5/32 in. per ASTM F436 flat washer** and **5/16 in. per beveled washer** to the grip + before selecting the length. +- **Where the add-to-grip table lives:** the per-diameter add-to-grip values are in **RCSC 2020 + Table C-2.2** (free, in the RCSC Commentary). RCSC itself points to a *more extensive* selection table — + **Carter (1996)**, *"Specifying Bolt Length for High-Strength Bolts,"* AISC *Engineering Journal*, + 2nd Qtr. 1996 (free, and RCSC's own cited reference). The AISC *Steel Construction Manual* has + historically tabulated the same selection (paid — reference only, never reproduced). + +This agent gives the **rule + grip concept**, not the tabulated length values — read Table C-2.2 in the +free RCSC PDF (or Carter, 1996) for the per-diameter add-to-grip numbers. + +> **Rule** → length develops the bolt only with sufficient thread engagement. **Condition** → every +> high-strength bolt; length = grip (+ washer thicknesses) + Table C-2.2 allowance, rounded. **Source** ↓. + +## Source + +- **Normative requirement — RCSC 2020 §2.7 ("Geometry of Bolting Components and Assemblies").** + *"The bolt length used shall be such that, when installed, sufficient thread engagement (as defined in + the Glossary) is achieved."* +- **Grip — RCSC 2020 Glossary.** *"Grip. The total thickness of material a bolt passes through, exclusive + of washers or direct-tension indicators."* +- **Sufficient Thread Engagement — RCSC 2020 Glossary.** *"Having the end of the bolt, not including the + spline of a spline-end bolt, or the available bolt threads extending beyond or at least flush with the + outer face of the nut; a condition that develops the strength of the bolt."* +- **Selection method — RCSC 2020 Commentary to §2.7, Table C-2.2.** *"To determine the required bolt + length, the value shown in Table C-2.2 should be added to the grip (i.e., the total thickness of all + connected material, exclusive of washers). For each ASTM F436 washer that is used, add 5/32 in.; for + each beveled washer, add 5/16 in. … The length determined by the use of Table C-2.2 should be adjusted + to the nearest ¼-in. increment (or ½-in. increment for lengths exceeding 6 in.). A more extensive table + for bolt length selection based upon these rules is available (Carter, 1996 …)."* +- RCSC's *"more extensive table … (Carter, 1996)"* is **Carter, C.J., *"Specifying Bolt Length for + High-Strength Bolts,"* AISC *Engineering Journal*, Vol. 33, No. 2 (2nd Qtr. 1996)** — the free, + canonical bolt-length-selection reference. (The AISC *Steel Construction Manual* also tabulates this + selection — paid; reference only, never reproduced. Edition numbering varies, so it is not cited to a + specific table number here.) +- Verified against the genuine RCSC 2020 PDF. Verify free at boltcouncil.org. diff --git a/40-diagrams/substrate-playground.html b/40-diagrams/substrate-playground.html index bfc748df9..60e64b75e 100644 --- a/40-diagrams/substrate-playground.html +++ b/40-diagrams/substrate-playground.html @@ -90,7 +90,7 @@