Tutorial 33: Bearing Seats & Embedded Angles

Tutorial 32: Reglets, Brick Ledges & the Masonry Interface covered bearing for brick, which is heavy but forgiving. This lesson covers bearing for steel, which is neither. When a beam lands on a panel, the panel is holding the roof up at that point — and the feature that receives it is cast in, once, before the pour.

Feature

What it is

Standard

In ConstructiVision

Bearing pad / stub-beam pocket

A cast bearing surface or pocket for a stub beam

TCA

built today — a recess, or the Pocket on a weld connection

Construction seat / bearing angle

A cast-in seat angle used for construction bearing

TCA Detail Library

planned

Embedded angle

A cast-in continuous, perimeter, or seat angle

TCA Detail Library

planned

Pilaster cap

A cap detail at the top of a pilaster

Architectural practice

partly — the stop height, not the cap treatment

The pocket is built today; the rest of the family is not

The stub-beam pocket is modeled now, and Step 2 is a follow-along you can run in your own panel. There is no button called Beam Pocket, which is why it is easy to conclude wrongly that there is no pocket: a pocket is a recess with a Z Offset of 0, and when the beam also has to be tied to the panel it is the Pocket columns on the weld-connection row instead. The user manual is explicit — “a value of zero (0) will place the block out on the surface for Beam Pockets, or architectural features.”

The construction seat and the embedded angle are not modeled, and the pilaster cap is only half there — the height a pilaster stops at is recorded, the cap treatment is not. Steps describing behaviour not in your build are marked (planned).

Note

A browser version covers part of this lesson. Open it here — it lists exactly which steps it does not cover, so you know what to come back to AutoCAD for.

What you will learn

  • How to place a stub-beam pocket today — two ways, and which one to use when the beam has to be tied to the panel as well as sit on it.

  • The difference between a connection and a bearing — and why ConstructiVision has to model them separately even though both are steel bolted to concrete.

  • What an construction seat is for, and why it is temporary in intent but permanent in the panel.

  • Why an embedded angle is dimensioned by its length and its ends, not by a point.

  • Why a pilaster cap is not just the top of the pilaster.

Before you start

Lesson

Step 1 — Connection or bearing?

Every feature in this lesson is a piece of steel cast into concrete. So is a weld plate. The distinction is not the hardware — it is the direction the load goes.

Load direction

Fails by

Dimensioned to

Weld connection

in the plane of the panel — it ties

tearing out

a point

Bearing

perpendicular, downward — it carries

crushing or rotating

a surface, at an elevation

A weld plate can be a point on a drawing because that is genuinely all it is. A bearing cannot: the steel lands on an area, and where the centre of that area sits relative to the panel face is the number the engineer cares about — it sets the eccentricity, which is what decides whether the panel sees a moment it was not designed for.

This is why a bearing feature that reports only an X and a Y is not enough, and why they are their own family in the catalog rather than a note on a connection.

Step 2 — Bearing pad and stub-beam pocket

A bearing pad is a prepared surface — often an elastomeric pad on a levelled area of concrete — that a beam sits on. A stub-beam pocket is the recessed version: the beam end sits into the panel rather than on a shelf projecting from it.

They are the same decision made two ways, and the trade is straightforward:

  • A pad keeps the panel section intact and pushes the beam out from the face, increasing eccentricity.

  • A pocket brings the bearing back toward the panel centreline, which is structurally kinder, but removes section exactly where the load is.

Both sides of that trade are buildable now, and they are built with controls you already know.

The pocket, on its own

Open Recess / Blockout with your panel’s drawing open. The pocket is one row of Recess and Blockout Details — six rows to a page, five pages. On a free row:

  • Enable the row, and leave Shape on Rectangle.

  • Distance and Elevation — where the beam lands: across from the panel side, and up from finished floor.

  • Width and Height — the pocket opening: the beam plus its construction tolerance.

  • Thickness — the pocket depth, how far into the panel it goes. This must not be 0; a Thickness of 0 cuts clean through and greys out On Face and Z Offset, which is the tell that you have made an opening rather than a pocket.

  • On Face — U or D, the face the beam arrives at. Which of those is “the outside” depends on Tutorial 28: Casting Orientation & Yard Layout.

  • Z Offset — 0. That single column is what makes it a pocket. The manual states it directly: “Enter the Z offset of the block out from the selected surface of the Panel to create Insulation Blocks for ‘Sandwich Panels’; a value of zero (0) will place the block out on the surface for Beam Pockets, or architectural features.” Zero opens the void to the face; anything else buries it in the section and you have made an insulation block instead.

Confirm with OK. The panel redraws with the pocket formed and dimensioned, and — this is the Step 1 payoff — the elevation marker reads from finished floor to the bottom of the pocket. That bottom is the bearing surface. The number the engineer cares about is the number the drawing states, not something inferred from a plate centre.

Tutorial 30: Blockouts Beyond the Rectangle covers the same row from the blockout side if you want the other shapes.

The pocket, at an embed

When the beam has to be tied as well as carried, the pocket belongs to the connection rather than standing alone. Open Weld Connections and look at the far right of the row: the Pocket columns, W / H / E / D. The manual describes them as being for exactly this — “Use the pocket options to create a joist, girder, or chord connection pocket around or above the embed.”

  • W — the width of the pocket. It is centred on the embed, so you do not position it separately.

  • H — its height.

  • E — the elevation of the bottom of the pocket relative to the top of the embed. A value of 0” places the pocket directly above the embed.

  • D — its depth.

Use this one whenever a plate and a pocket describe the same piece of steel landing. Because the pocket hangs off the connection row, the two cannot drift apart when somebody moves the connection — which is the failure the standalone recess is exposed to.

One caution that follows from E being measured off the embed: the pocket’s bearing elevation is derived here — it is the connection’s elevation plus E — rather than typed. If the bearing elevation is the figure the erector has to hit, check what the drawing actually reads after the redraw rather than trusting the number you entered.

And the pad

The projecting version — the shelf that a beam sits on rather than in — is a thickening of the wall, and ConstructiVision places it through Pilaster / Lintel Details. The manual names it in passing: “A Lintel (Corbel) is a thickening of the Panel wall above the bottom of the Panel.” Tutorial 38: Corbels, Haunches & Spandrel Seats is the follow-along for that side of the trade, and it is worth doing straight after this one — the two lessons are the same structural decision from opposite ends.

The elastomeric pad itself is not a catalog item. What you record is the prepared surface it sits on.

What is still missing, and both are worth knowing before you rely on the output:

  • There is no dedicated bearing-length field. How far the beam sits into the panel is the pocket’s Width or its Height, depending on which way the beam runs, so the number is recorded — but it is recorded as an opening size, not called out as a bearing dimension in its own right. Where the bearing length is what the erector has to hit, note it on the drawing as well.

  • The materials list does not distinguish a pocket from any other void. The pocket is drawn, dimensioned and quantified, but nothing in the list separates it from a blockout of the same size. A fabricator reading the panel book sees the pocket on the elevation; they do not see it flagged in the schedule as something that carries a beam.

Recorded, not certified

ConstructiVision records the bearing dimensions and elevations you enter and carries them to the drawing and the schedules consistently. It does not calculate bearing stress, check the eccentricity, or size the pad. Those are the engineer’s, and nothing here substitutes for the structural drawings.

Step 3 — Construction seat (planned)

A construction seat is a small angle cast into the panel that a steel member rests on while it is being set — before the permanent connection is welded or bolted. The ironworkers land the beam on the seat, let go of the crane, and make the real connection with the load already supported.

Two things follow, and both matter to the drawing:

  1. Its elevation is tighter than the permanent connection’s. The beam has to arrive at the right height, so a seat that is half an inch low is half an inch of shimming for every beam on the job.

  2. It stays in the panel forever. “Temporary” describes its job, not its life. It is cast in, so it is in the panel book, in the materials list, and in the embed schedule.

Intended behaviour: a seat row taking elevation, angle size and projection, marked as a construction seat in the embed schedule so the fabricator can tell it from a permanent bearing angle at a glance. They look the same in section and they are ordered from the same shop.

Step 4 — Embedded angle (planned)

An embedded angle is the general case: a length of angle cast flush into the panel, along an edge, a perimeter, or a run in the middle of the face. Weld plates attach to it, or steel bears on it, or both.

The critical difference from everything else in this lesson: it has a length. A weld plate is at a point; an angle runs from somewhere to somewhere, and where it stops is as much a dimension as where it starts.

Intended behaviour: an angle row taking a start, an end, an angle size and a face offset, dimensioned at both ends. The materials list reports it in linear feet with the section size, because that is how angle is bought — a count of angles is meaningless.

What you can do today is define a long, thin embed type in the connection catalog (Add weld connections → Edit Embeds) and place it like any other connection. That records the angle’s presence and its overall size, and it is better than leaving it off. It is not the same thing: the embed is placed to a point and reported as a count, which is precisely the pair of limitations this step exists to describe. Treat it as a stopgap and dimension the ends by hand.

Tip

An angle that runs the full panel width is the easy case. The one that catches people is the angle that stops short of a panel joint so the two panels can move independently. That gap is deliberate, and a drawing that shows the angle running edge to edge will get it built wrong.

Step 5 — Pilaster cap (partly planned)

A pilaster (Add a pilaster or lintel) is a thickened column within the panel. Its cap is the detail at the top — where it stops, and how.

A pilaster cap is a real feature and not simply “the top of the pilaster” for two reasons:

  • The pilaster usually stops below the panel top, so where it stops is a dimension with nothing else to derive it from.

  • Something normally lands on it — which makes the cap a bearing surface, and brings it back to Step 1.

The first of those is already handled. Height on the Pilaster / Lintel Details row is where the pilaster stops — a value of 0 runs it to the top of the panel, and any other value stops it short, which is the dimension the first reason is about. So the stop elevation is recorded today (Add a pilaster or lintel).

Intended behaviour, for the part that is missing: a cap treatment on that same row — square, sloped, or bearing — with the bearing case carrying the same values as a bearing pad. Sloped caps exist to shed water, so the slope direction would be part of the record. Until then, a cap that has to shed water or receive a beam is a note on the drawing, and where something lands on it you can place the bearing itself with Step 2.

Check your result

You should now be able to:

  • State the difference between a connection and a bearing, in terms of load direction rather than hardware.

  • Say why a bearing feature cannot be dimensioned as a point, and name what it is dimensioned to.

  • Explain the pad-versus-pocket trade in one sentence each way.

  • Point at a stub-beam pocket you have placed, and name the single column that makes a recess a pocket rather than an insulation block.

  • Say which of the two pocket methods you would use when the beam is also tied to the panel, and why.

  • Say where the bearing elevation is stated in each method, and which of the two derives it rather than stating it.

  • Name the two things a pocket does not give you that you have to put on the drawing yourself.

  • Say why a construction seat, which is temporary in purpose, appears permanently in the panel book.

  • Explain why an embedded angle is reported in linear feet and not as a count.

  • Name the two reasons a pilaster cap is its own feature, and say which of the two the product already records.

Where next

A companion video for this lesson is planned alongside the written curriculum. Step 2 is followable today; the remaining steps will be recorded as those features arrive.