I typicaly analyze CMU shear wall by calculating the relative stiffness of the elements. Recently, I modeled a wall with RAM Elements masonry wall module and was surprised by the FEM results. The piers between window attracted more lateral load than I expected. I then performed a calculation by...
The Applied Technolgy Council (ATC) has a beta version for a Hazard Mapping Tool for the US. It looks promising with wind, snow, tornado and sesimic design values. Includes design values for ASCE 7 (-05, -10, and -16) and ASCE 41 (-13 and -17).
https://hazards.atcouncil.org/#/
There are two closed threads that discussed the apartment balcony collapse in Berkeley where 6 people died. http://www.eng-tips.com/viewthread.cfm?qid=389528 http://www.eng-tips.com/viewthread.cfm?qid=389494
California's Contractors' State License Board (CSLB) has filed a complaint and may take...
In the 1998 and 2005 D1.4, the table for essential variables includes a change in position not qualified per 6.2.4 which implies any change in position requires a new PQR. However, the 2011 edition's table of essential variables references 6.3.4 which is in the section for welder qualifications...
The February 2015 edition of Modern Steel has a new version of "Are You Properly Specifying Material" Some interesting changes such as ASTM A500 grade C is the preferred specification for HSS (it was grade B). It is worth a peek...
I am soliciting thoughts on when housekeeping pads for equipment inside buildings should be isolated from the slab on ground. These are pads that are placed on the ground and separated from the building slab with an isolation joint rather than a housekeeping pads placed on top of the slab. Is it...
Are there standard sizes for hand hole fittings for pipe columns or similar? The hand holes are for electrical. My internet search results have not been successful. I have found a couple manufactures that sell generic replacement covers for light poles. I was hoping to find manufactures of cover...
I decided to make a spreadsheet to convert units that are commonly used in structural engineering and I have a couple questions:
Force: Are kilogram-force measurements ever used? I have seen a Basis of Design by Americans that used kg/m² for live loads. Is this incorrect or do some areas use...
Today is the 50th anniversary of the largest earthquake in US history. The 9.2 magnitude quake occurred near Anchorage, Alaska.
http://www.latimes.com/science/sciencenow/la-sci-sn-1964-alaska-earthquake-50-years-anniversary-20140327-dto,0,7347070.story...
I am curious how the compression test results vary when masonry grout is molded in cylinders designed for concrete versus absorptive masonry molds per ASTM 1019 Standard Test Method for Sampling and Testing Grout. My guess is the cylinder strengths would be less because the masonry mold removes...
What documentation do you expect to see in a concrete mix submittal that is designed with trial mixes per ACI 318 rather than field experience? I am accustomed to submittals with field experience where a summary of the test result are provided and the statistical calculations justifying the...
I am looking an article or documentation that explains why the IBC allows a 40% increase in shear wall and diaphragm capacity for wind loads, while the 97 UBC did not allow the increase. In a 2008 thread (http://www.eng-tips.com/viewthread.cfm?qid=223905) UcfSE posted a link to and article that...
Is the relative rigidity of wood shear wall segments on the same line usually considered in the design?
In Design of Wood Structures, 6th edition, Breyer states "For a wood structural panel segmented shearwall with an aspect ratio (h/b) not greater than 2, the unit shear is generally assumed to...
If you are looking for some current seismic design examples, NEHRP Recommended Seismic Provisions: Design Examples, FEMA P-751 is online. I could not download the entire document, but I could download all of the chapters.
http://www.nibs.org/?page=bssc_2009pubs&hhSearchTerms=P-751#FEMAP751
It is common to see cold formed steel jamb details with 2 or 3 studs welded together. However, there is no guidance for transvere shear strength of Flare-V Groove welds in AWS D1.3 or AISI S100. Am I missing something, or are there any other references for the strength of Flare-V goove welds in...
Is ASTM A706 reinforcing typically specified when using strength design for masonry? Section 3.1.8.3 of the masonry code (TMS 402-08/ACI 530-08/ASCE 5-08 and TMS 402-05/ACI 530-05/ASCE 5-05) states ” The actual yield strength shall not exceed 1.3 multiplied by the specified yield strength.”...
