Thread 507-441956 and 725-244744 ask why and if weep holes are required in tube members. A lot of people gave their opinion and some were correct but no one in either thread gave any references to back up their opinions. Basically both threads are now closed and no real information was given in...
"In order to reduce tension on a PT strand, tension must first be added- the jack and stool are attached and the tendon is stretched so that the nut on one end can be loosened by hand. So, for a short period, the PT strand being loosened is under significantly more tension, and is applying...
I agree with Ron that the treads should be reinforced. Rather than aluminum I would recommend carbon fiber strips.
Sika Carbodur strips is a product that I have had success using.
On stairs, impact must be considered as someone might run up or down the stairs hence the need for tensile...
I am still using 7-10 so I am not familiar with the Chap. 26 provision.
From experience I have found ASCE 7 to be extremely vague on the treatment of partially open buildings.
After Hurricane Ike went through Ohio in 2008, I observed several buildings of the partially open and three sided...
"Time will tell who failed whom, but, if it is discovered that an Engineer(s) did fail here, I am very comfortable that Engineers have vastly improved living conditions, chemicals, medical equipment, prescription drugs, transportation, petrochemicals, utilities, agriculture, food, etc., etc...
If you look at the 5 second video posted by MattOhio in the first thread, you can see the initial collapse point was at the bottom chord on the canal side of the bridge (the node where 9 & 10 intersect in the diagram near the beginning of this thread). If the failure was due to bending the...
Were the skip joists used under the concourse or is this a picture of the underside of the roof?
Skip joists are generally used for roofs not floors, especially floors that would require a 100 psf live load.
Section 5.3 of the steel joists specs requires that joists have a minimum bearing of 4" on masonry unless a detailed bearing analysis is performed. Steel beams generally have more load than joists. 4" would be a minimum for bearing. I generally use 250 psi bearing pressure and size my bearing...
I down loaded chapter 3 from TPI-1 2007 and the table on effective plate values is the same.
See page 22.
http://www.tpinst.org/ANSI_TPI1-2007_Ch%203_QC_web.pdf
I am not sure which edition of TPI 1 you have.
In the 2002 edition there is a table for effective tooth embedment (A3.4-1)
0" <G< 1/32" 100% effective
1/32" <G< 1/16" 60% effective
1/16" <G< 3/32" 40% effective
G> 3/32" 0% effective
If you have 1/8" gaps those trusses should...
The shape sizes changed in the 7th Edition (1970)
The web thickness of a 12B19 is 1.2% thicker than a W12x19 and Rx is 1% smaller than the same values for a W12x19. In other beam sizes the weight increased or decreased from previous sections.
The changes were made to standardize how sections...
You should note that turnbuckles have a lower capacity than the rods.
If you don't want to upsize the rods, I suggest you specify sleeve nuts instead.
As a practical note, balconies supported by rods can be very bouncy. A classical example was the Russian Pavilion at Expo '67 in Montreal.
I...
I have a Burger joist catalog from the 1970s.
They have a table that lists the chord properties but the they designate their chords using an odd section number.
I was able to determine from their chart that the joist I am analyzing has a chord section number 0859 but they do not
say how this...
One of the main problems was a slow response by the people in charge. A severe storm warning had been issued about 25 minutes before the collapse, but officials did not warn the crowd until a few minutes before the wind hit. People had started to leave but with a large crowd they did not have...
