I have a client that wants to replace a roof with T304 3N metal decking. They need to comply with FM Global attachment requirements, thus requires being welded. Are there any concerns of welding T304 to A992 with puddle weld attachments? I am concerned with welding dissimilar metals.
AUCE98
Has anyone had experience with the use of Xyland coating on A325 or A490 bolts. It appears to be a corrosion resistance coating similar to Teflon. My concern is the possibility of the nuts loosening over time. The manufacturers website indicates that a better, more accurate torqueing value is...
This is a picture of a concrete vault wall, 24-inches thick, 18 feet tall and below the water table. The plastic item in the middle appears to me to be plastic form tie of some sort, which I have never seen before. Some of these plastic items are hollow. Others appear to have some sort of...
I am putting together a proposal for a project that will require SCBF's. Does anyone have a good feel for the amount of additional time that would be required for design / detailing (as a percentage of total engineering cost) as opposed to a project with R=3 ?
What are some your favorite interview questions to gauge competency of a structural engineer ?
My favorite is to ask someone to explain the generation of seismic forces in layman's terms.
On a current industrial project, the client is wanting to reuse existing wood pile foundations for the support of a new storage silo. The piles are currently supporting a similar silo, the new one may be slightly heavier. My concern is the age of the piles and the expected service life of the...
I am currently working on a project that is requiring an existing mat foundation to be extended to accommodate the new loading and revised column locations. The mat extension will be the same thickness as the existing foundation. The existing foundation has sufficient reinforcement for the...
I need some suggestions. How would you handle a government plan reviewer which is telling you that “your building is over-designed” yet they have not performed calculation #1 to show where anything is incorrect. I am being told that full pen welds on a moment frame structure only need to be...
I am reviewing a drawing which has dimensions on plan which are to the 1/8". My question is how reasonable is this to assume? Especially due to the fact it is a foundation plan. I would like to round it to the nearest inch and call it good. Any thoughts are welcome
I would like some opinions regarding the application of live load for a portion of a structure that I am currently designing. The structure is an enclosed stair tower extending from a lower parking lot level on grade up to street level adjacent to a viaduct. The building is located...
Does anyone have a good source to find an approximation of the forcing function due to vortex shedding? I am looking to compare the frequency of a suspended pipe relative to the vortex shedding due to wind to ensure there is not an issue with resonance. Any help would be appreciated.
AUCE98
Does anyone have experience with substituting ASTM A513 square tubing for ASTM A500? ASTM A500 is recognized in the AISC as well as AISI Cold-formed Steel Design manual, and is typically what is specified for structural applications. The issues that I am aware of are the low carbon content in...
I am reviewing the lateral strength of a mechanical enclosure that is comprised of light gauge stud walls with (2) ½” sheets of gypsum board on both faces. IBC table 2306.4.5 provides values for allowable shear forces for wood assemblies, but not light gauge metal. Does anyone know if these...
I am looking for a reference that may provide some guidance for live load of a recycling facility floor. At this point we are estimating that the controlling factor for thickness of the slab will be a wheel load of front end loader of an undetermined capacity. My initial guess is 400-500 psf and...
When modeling a mat foundation supported by piles, is it common practice to modify the pile spring constant such that all pile share the load without exceeding their allowable values. This analysis is being performed in RAM Concept, so the program is taking into account the relative stiffness of...
I have been asked to design a residential home on elevated piles. The project is located in Mass, along the coastline. My intent is to design the piles using Lpile, however, I have a question regarding the lateral loading. Can anyone point me to a reference that provides the proper loading for...
Has anyone heard what the status of the new version 6.0 of Enercalc is? It seems that it has been promised to come out for at least a couple of years now.
I would like the communities opinion on an issue faced currently in our office. We are designing a 4-level wood framed structure placed on a PT podium slab. The typical live load for the wood framed portion of the structure is 40psf. How is the live load reduction applied to the podium slab...
IBC 2000, live load reduction is based on tributary area associated with the loaded element. In a load bearing wood wall, does the code consider the entire wall or the individual stud as the element to consider for the tributary area. My understanding is that if there is a mechanism for...
