Pipe Support Structural Design — Whole Load Path in One Run
PiperSTR designs the structural steel that carries your pipe. Enter the support once — arms, column, base plate, anchors, pier — and one run walks the whole load path: the pipe load on an arm becomes the arm's moment, the arm's reaction becomes the weld demand, the column carries the accumulated axial and biaxial moment down to the base plate, the anchors, and the soil. Every check names the AISC or ACI clause that governed. It runs in your browser: no solver, no API call, no per-run cost.
Content last reviewed · page regenerated 2026-09-14 at build.
What it checks
Most tools make you run four separate calculators and hand-carry loads between them — a member check here, a base plate there, an anchor calculation somewhere else. PiperSTR runs the cascade in one submit, so changing a pipe load on an arm updates the anchor tension and the soil pressure immediately. That single property is the whole point of the tool.
The load path, in order
| Arm | AISC 360-22 Chapters D, E, F, G and H — tension, compression (including flexural-torsional and slender-element effects), flexure with lateral-torsional and local buckling, shear, and combined forces. Plus a deflection check, which pipe-support spans frequently govern on. |
| Welds | Fillet welds per J2 with the J2.4(b) directional strength increase, at both the arm-to-column and column-to-base-plate joints, checked against the base metal as well as the weld metal. |
| Column | The same member check, carrying the accumulated axial load plus biaxial moment from every arm and any lateral load at the top. |
| Base plate | Concrete bearing per AISC J8, and plate yielding at both the bearing and tension interfaces per AISC Design Guide 1 — including the shortened bearing block that governs when the eccentricity pushes past the kern. |
| Anchors | ACI 318-19 Chapter 17: steel strength in tension and shear, concrete breakout both ways, pullout, side-face blowout, pryout, and the 17.8 tension-shear interaction. |
| Pier and soil | Bearing pressure, overturning, sliding and two-way punching shear — or, for a pier doweled into existing concrete, the anchorage check that actually resists overturning there. |
Sections and materials
1,506 AISC shapes are built in: W, M, S, HP, C, MC and WT transcribed from AISC's freely published Shapes Database v16.0, plus L angles, rectangular, square and round HSS, and Pipe computed from nominal geometry per Specification B4.2. Both design methods run from one nominal-strength core, so you can switch LRFD to ASD and compare the same design without re-entering anything.
Output
- Stage table — every component with its maximum utilisation ratio, the limit state that produced it, and a pass/fail verdict.
- 3D model — the assembly to scale, each member coloured by its own utilisation, so the governing element is visible before you read a number.
- Design Summary Report — a PDF with the title block, design basis and factors, geometry, applied loads, base reactions, every check with its clause, and the assumptions the run made.
- Report Manager capture — the whole cascade lands as one calculation in the same report package as the stress and spring calcs beside it.
Who it is for
PiperSTR is aimed at the engineer who owns the pipe and inherits the steel underneath it:
- Piping engineers sizing standard support assemblies against real pipe loads instead of picking a detail off a standard and hoping the span is covered.
- Plant and maintenance engineers checking whether an existing support can take a new line, a re-route, or an added tier.
- Structural engineers who want the pipe-support case without modelling a frame — the parametric configurations are determinate, so the answer is closed-form and reproducible.
Five configurations ship: T-post, multi-tier, cantilever off existing structure, goalpost/portal, and trapeze — with presets for two common standard details.
Honest limits
Two things it deliberately does not do. It does not embed proprietary anchor qualification data: the characteristic bond stress of an adhesive anchor, and any product-specific effectiveness factor, come from your ICC-ES evaluation report. Leave the bond stress blank and the tool tells you the bond check did not run rather than quietly passing the anchor. And it does not select allowable soil bearing, friction or cohesion — those are geotechnical report values, always entered by you.
The parametric configurations are statically determinate by construction. A braced frame, a continuous header spanning several supports, or a support whose stiffness interacts with the piping system needs a frame analysis, not this.
Demo video
▶
AISC 360-22 Pipe Support Structural Design Calculator - Member, Weld, and Anchor Design (2:14) — One run down the whole load path — AISC 360-22 member and J2 weld checks, Design Guide 1 base plate, ACI 318-19 anchors, pier and soil — with the 3D assembly colored by utilization ratio. Watch on YouTube.
FAQ
What codes does it use?
AISC 360-22 for the steel — Chapter B4 classification, D tension, E compression including E4 flexural-torsional and E7 slender elements, F2 through F10 flexure, G shear including the G2.1(a) exemption, and H combined forces — with AISC Design Guide 1 for the base plate, including the shortened bearing block that governs when eccentricity pushes past the kern. ACI 318-19 Chapter 17 covers the anchors — steel strength, breakout both ways, pullout, side-face blowout, pryout, and the 17.8 tension-shear interaction — and Chapter 22 the two-way punching shear at the pier. Both LRFD and ASD run from one nominal-strength core, so switching design method re-factors the same nominal strengths rather than re-deriving them, and you can compare the two on an identical design without re-entering anything. Every check in the output names the clause that produced it, which is what lets a reviewer audit the run instead of trusting it.
Where do the section properties come from?
W, M, S, HP, C, MC and WT shapes are transcribed from AISC's Shapes Database v16.0, which AISC publishes free alongside the 16th Edition Manual — 1,506 shapes ship built in. That release carries no angles, HSS or pipe, so those families are computed from nominal geometry, and the computation choices are deliberately conservative: angles use a sharp-corner idealisation that lands within 1% of published values and errs low, so the capacity you get is slightly under what the Manual would give, never over; HSS and Pipe use the Specification B4.2 design wall thickness of 0.93 × t_nominal, which is the code's own answer to mill undertolerance rather than a private assumption. The distinction matters at review time: transcribed properties can be checked against the database line by line, computed ones against the stated method. Confirm final selections against the Manual for your governing edition — v16.0 tracks 360-22, and a job still on 360-16 can differ in the margins.
Does it check deflection?
Yes, per arm, against a limit you set — L/240 by default. This matters more than it sounds, because pipe-support spans are frequently governed by deflection rather than strength, and several commercial member-design modules check ultimate limit states only. Run the numbers on a typical cantilever arm and the pattern shows up immediately: a section that passes flexure with margin to spare sags past L/240 at the tip, because stiffness scales with I while strength scales with S, and short heavy loads punish the former. The consequences of ignoring it are not cosmetic. An arm that deflects visibly re-pitches the line it carries, which on a drained or two-phase line is a process problem; and under a spring hanger location, support settlement directly eats the spring's working travel — the load the stress model assumed at that node quietly redistributes to its neighbors. A support that passes every strength check and still sags is a support that failed; the tool treats it that way.
Why did my standard detail fail overturning?
Almost certainly because it is modelled as a gravity spread footing when it is actually doweled into existing concrete, and the arithmetic makes the point better than the words: a light T-post carrying pipes cantilevered to one side puts its resultant well outside the footprint of a small pier, and the overturning moment from a few hundred pounds of pipe at a 24 in arm eccentricity easily exceeds what a 24 × 24 in pier's own weight can restore. On a gravity footing that is a legitimate FAIL — the fix is a bigger footing or a counterweight. But most standard details in a plant are not gravity footings; they are piers doweled or post-installed-anchored into a slab or mat, and there the anchors resist overturning, not the concrete's weight. Switch the pier restraint to anchored and the check moves where it belongs: the anchor stage picks up the tension from the overturning couple and runs it through the full ACI 318-19 Chapter 17 suite instead.
What tier do I need?
PiperSTR is an Ultimate tool ($14.99/month or $149/year), alongside PiperFEA and PiperISO. Unlike an FEA run it executes entirely in your browser from the same calculation core the free calculators use — there is no solver queue, no per-run cost, and nothing leaves the tab, which also means the run is exactly reproducible: the same inputs produce the same report forever, the property every calculation this site ships is built around. The free tier is not a demo of this tool, but it is the same arithmetic family: all the ASME code calculators — wall thickness, spans, SIFs, spring variability, the checks that feed a support design its loads — stay free with no account, permanently. The practical evaluation path is to run your support's loads through the free pipe-support-spacing and spring-hanger cards first; if the numbers those produce are worth carrying down the load path into member, weld, plate, anchor and soil checks in one submit, that is what the subscription buys. Details at /pricing/.
Can I use it for a rack or a braced frame?
No, and the refusal is structural rather than commercial. The five configurations it ships — T-post, multi-tier, cantilever, goalpost, trapeze — are statically determinate by construction, which is precisely what makes the answer closed-form and reproducible: every load path can be followed by hand, every reaction is unique, and two engineers running the same inputs get the same numbers with no solver settings to argue about. A pipe rack with continuous beams over several bays, a braced frame, or a support whose stiffness feeds back into the piping analysis breaks that property — those systems are indeterminate, their member forces depend on relative stiffness, and they belong in a frame solver that models it. The boundary is worth respecting in both directions: forcing a determinate tool to approximate a rack produces confident wrong numbers, and modelling every standalone T-post in a frame program wastes hours on a problem with a closed-form answer. Use PiperSTR for the standalone support; take the rack to structural software.