Does the NDS have a required (maximum) diameter for hole size in a flitch steel when fastening it to a wood member? Or does anyone have suggestion what size hole to put in the steel plate? The application is an 1/8" steel plate fastened to the side of an existing glulam purlin with 1/4"...
I have an interesting problem to solve, and thought I ask if there are any suggestions or standards and design manuals available that may help. The problem is in a late 1960's era 116' diameter x 90' bulk storage bin. At the interior, the rotating bridge is supported by a 11'-6 diameter...
How are engineers treating spring isolators used to support exterior mechanical equipment supported by steel framing? Specifically is there a torsional force in the steel supporting framing from either vertical or horizontal loading? In the applications I'm referring to a spring isolator is...
I have a small commercial building using bottom chord bearing open web wood joist @ 16" o.c. spanning 54' with 1/2":12" slope, and bearing on a 2x6 wood wall. Low side heel depth is 32"-36". Not sure what is the most common or economical means to transfer the horizontal diaphragm to the shear...
Does anyone know the history - reasoning - purpose behind IRC section R502.6.1 - Opposite floor joist over interior supports lapped 3"? In this case there are 2x8 floor joist spanning 8' to 9' butt together over a double LVL beam and NO wall above it. A home inspector is saying telling a...
What is or used as OSHA's definition of an "adequate gripping surface" for a steel fixed ladder side rail? Specifically the cross section shape. I've read OSHA's interpretation letter of August 8, 2005 stating a 2" angle iron isn't considered to meet the requirement. I've also read reference...
I need to design a stand and anchorage for a centifuge in an animal rendering facility. I observed an existing installation, and there was a lot of lateral movement, but the stand was not well braced. Centifuge total weight is 4,600lbs of which 1,000lbs is rotating at 115rpm. The centrifuge...
The attached cross section shows an existing 12:12 slope structure (x 24' run), solar panels installed a few years ago with standoffs fastened to the sloped roof, and a proposed new skylight system installed on a 30" high side curb at the base of the sloped roof. There are 4 existing skylights...
Does anyone have information, load tables or physical measurements and materials used, of pre-engineered metal building trusses shown in the attached photo? Reportedly the building was built in the early to mid 1970's, and I'm fairly sure it's a Butler building. A side question, is anyone else...
For use in the USA, what is the appropriate design specification to use for a below the hook lifting device made of 3 7/16" solid round AISI 1018 material? It will be used to lift coils of conveyor belting material. Thanks in advanced for your time and thoughts.
Does anyone have information on design loads, and other considerations, for data storage centers. Evidently there are different Tier Level ratings depending on the level of safety/security to meet the client's needs. Thanks
There have been several posts about design of wood framed cathedral ceilings using a ridge beam for gravity loads, but what about the connections and horizontal loads for cathedral ceilings with valley and hip conditions? Should a connection between 2 joists at a valley or hip still have a...
I saw an unusual problem and I'm wondering if anyone else has. On hail damaged asphalt shingle roof, diagonal cracks at 3 foot spacings can be seen in the shingles. See attached photo. When on the roof, there are more cracks than can be seen in the photo. The cracks aren't due to hail damage...
I'm a structural engineer looking for information to help a client on a problem they have outside my area of expertise, so forgive my invasion of the ME forum. The problem is HVAC registers are discharging onto insulated glass units causing the seals to fail prematurely. The attached photos...
Is there a maximum width between ladder rails for fixed ladders? Background for the question is I designed a steel platform to support a new equipment installation. The new platform is to be accessed from an existing platform that is 24" lower. A ladder was shown for access with a flared 24"...
We're a small structural engineering firm looking for advice on getting either an older HP 650C from a another engineering firm relatively inexpensively vs buying a new HP 510. Currently we run an old version of AutoCAD but that will be changing soon, and our plotting needs are limited. My...
I'm fastening an electric winch to a rectangular HSS and I want to verify if I am correct on the amount of torque the winch will develop. Take the line load x the distance from the center of the winch to the line? For example 2,000lbs x 8" = 16,000in-lbs of torque from the winch. What about...
Has anyone every run across design information on overhead theater loads? I've been asked to review if an existing theater steel truss roof system can safely support the installation of new higher capacity head blocks. The existing drawings do not show design loads. The building was built in...
I've got questions regarding an existing 12' tall 12" CIP basement wall I've been asked to analyze. The wall is grossly under reinforced with #4 @ 24" E.W. located in the middle of the wall. The wall has a keyway at its base. The wall shouldn't be standing. The question I'm trying to answer...