32C-149 Project Meeting Minutes 121031 RH email1
Peter Frothingham, RA
From:Ryan Hellwig <rshpe@crocker.com>
Sent:Thursday, 01 November, 2012 16:39
To:Michael Fitzgerald; Lou Gallinaro; R & S HEWETT; Peter Frothingham, RA
Subject:Re: McCarthy steel questions
All,
I took a closer look at the steel questions this morning up on the scaffold, and I observed the following:
The cap plate in detail 7/S1 (5/8" x 4-1/2" x 12-3/4") was installed as 3/4" thick, not 5/8 to match the
flange. This thicker plate has almost 50% greater bending capacity than the 5/8" plate, and so the stiffener (3/8"
x 2-1/2") may be omitted. In other words, it is not necessary to install the triangular gusset plate that we
discussed in the meeting yesterday. Which is good, because the electrical wiring was already run across the
beams and columns.
The bottom flange continuity plates on the posts (5/8" x 4-1/2" x 3-3/4" - also in detail 7/S1) were only tack
welded in a couple of locations. There should be more weld.
Because the attic floor joists change direction near the middle of the wall, the Simpson H6 ties in detail 6/S1
cannot be installed as shown where these joists are parallel to the wall. Instead, provide solid blocking and 18
ga straps similar to the 3rd floor, except the straps will be on top of the joists, not underneath.
The 3x3 angle braces of detail 8/S1 at column D are skewed to the beam. Therefore it is not the same condition
as at column A. Being skewed, the capacity will be less than those that are perpendicular. Also, those angles
are attaching to wood blocking, and so will have less capacity than those attaching to brick. That is why I want
the two angles as shown at column D, even though there is only one shown at column A. Because of the
placement of the column relative to the demising wall, the second angle will just miss the column, and will have
to connect to the beam, but it will be close enough.
Detail 8/S1 calls for solid blocking between the joists above the 3x3 angle, but the blocking was not visible in
all locations.
Sincerely - Ryan
Ryan S. Hellwig, PE
Structural Engineer
Northampton, MA
Tel: 413 584 HLWG (4594)
rshpe@crocker.com