The 12" deflection is from inspection out of plumb. The columns are made of W12x14 & W12x14 welded at 90oC. The column is deflected in the direction as shown of the arrow. It was built in 1968, so i assumed it is A36 materials.
Hello,
One of my storage tanks has significant column deflection, approximately 12" from top to bottom. The rafters and columns are laid out in the attached photo.
Question: what is the K-value for checking the buckling or unsupporting length of the column?
I think the K-value should be 1.2...
Thank you shvet for the reference document. The Bob Long & Garner book " Guide to Storage Tanks & equipment" is great. I was able to find the reference and read it.
In my case, the tank will be 58ft dia. x 50 height with a spiral staircase. API 650 does not provide specific requirements for...
Hello all,
I need to estimate the allowable soil bearing capacity of the existing grade for a crane pad.
I know the ground bearing pressure excerpt by the crane from the lifting study.
I have a couple of boreholes (within 100m) of the crane pad location. Borehole shown material of each...
Hello,
I’m new to the above ground storage tank.
I’m looking for a design guide for spiral staircase on storage tank.
1. When to use staircase vs ladder? Please provide reference.
2. Min & max dimensions of run and riser. Max landing distance. Min stair case width. Do we have to follow OHSA...
We are working on an old refinery. The existing piperack was built in 1945 with Standard Oil Co. specs. We are unable to locate the spec.
By searching around, our best guess the material for steel pipe that time was either ASTM A53 or A7, the Fy= 35ksi.
Do you have AISC ASD 4th edition? I hope...
Thanks Skeletron
From LEG REACTION DATA, there are only download or uplift and shear. However, other than resultant of axial and shear the TOWER FOUNDATION DATA there are also huge bending moments. All leg and diagonal members come to the baseplate. Where’s bending moment coming from? unless...
Hello,
has anyone used TSTOWER FOR SELF-SUPPORTING LATTICED TOWERS. I have read the manual and tried to understand the differences between "LEG REACTION DATA" and "TOWER FOUNDATION DATA"
Which one is used for foundation design ? and why the download/uplift from Leg reaction data different than...
Yes. HDA anchor from hilti. However, the HDA was designed based on european code , ETAG 001
I was looking for section in ETAG 001 that have guideline for designing an anchor under dynamic load but no luck.
Thanks
Hi all,
I'm designing drop-in concrete anchor for new vibration clamp on existing vibration pipe. The vibration clamp is directly installed on existing concrete column with drop-in anchors.The anhor is under dynamic (cyclic) load (1000 lbs p-p).
I'm confusing on using type of anchor, undercut vs...
I have a case that the support can move in X and/or Z direction to a maximum of 6mm, i.e delta X or delta Z < 6mm, there will be no reactions in X or Z. If delta X or delta Z > 6mm, then I will have reactions on support.
How do I model this type of support in staad ?
I appreciate your input...
Thank you for all input. I have used Geospan void form by Plasti-fab. You can find the product specification and design manual in their web site.
Void form can be used but piles have to be designed to take all loads plus uplift forces which is transfered from void form to foundation due to...
Hi all, this may be old to someone but i need your input on frost heave design for my foundation.
I'm designing an unheated structural slab supported on piles. Design depth of frost penetration is 2700mm from soil report. I'm going to use Dow ethaform void form but i dont know how to calculate...
I'm looking for the sketch or dwg that show the detail of hinged grating cover. Basically, I have a ladder going down from grating floor to the slab below ( 6m high). I need to provide the grating cover the opening for the ladder. This grating cover can be lift up with hinged end.
Any link or...
Hi all,
We design foundations of the oil tanks (diameters vary from 30-55m, height 12-13m) sitting on gravel foundation. and the problem come to decide if we use geotextile as a secondary liner of the tank below 5 feet depth of gravel fill, if the tank bottom temperature constantly 90 degree...
The embedment of the H steel pile into pile cap for transfering load can be based on the CSRI handbook or discuss in thread 256-152354 , about 6" and no need the cap plate. But the topis for circular I could not find any where.
Normal practice from my company is the base plate as in column but I...
Thanks for all the info. now the problem come to decide if we should use the high temperature geotextile as a secondary liner of the tank , which can resist more than 100 degree celcius for long period, or use the normal geotextile , as the manufacturer say can only resist not more than 60...
We have a oil tanks of about some 150ft diameter and 40ft heigt, and rested on the 1m thick of 80mm minus gravel pad, and the edge is either reinforced with 1.5m thick of 40mm minus gravel ring or concrete ring wall. There also two columns support the roof of the tank. Do you think that under...
