I got a set of foundation drawings for a prefab building from a prospective client. They said these drawings are from very good but pricey engineer, they want me to design foundations for other similar buildings. I started to review these drawings and found lots of mistakes and other items I...
I am looking at the design of a billboard foundation. The pad portion has two layers of reinforcement, top and bottom. The foundation is subjected to high moment. Can someone explain me why do we need top pad reinforcement? sketch is attached.
what exactly do yo umean by constatn eccentricity? and if eccentricity exist at the connection (i.e. anchor bolts) shouldn't the connection experience the moment?
I have a tower pipe leg, reinforced with a single angle welded along its length. The reinforcement changes the centroid of the new reinf. leg and thus creates a load eccentricity. When a uplift load is applied to the leg, that extra eccentricity creates an additional moment that has to be taken...
According to he calculations, all three conditions are true. all actual stresses are a lot smaller than allowable stresses. Laminated pole is 50' tall, 18"x16" cross section. I use E=500,000psi.
but does it applies to poles? as they have insignificant amount of compressive load. adding both flexural components along the long side and the short side yields a value over 1.0.
I have a laminated wood pole, that is subjected to a moment at its base, compression load is minimal. Does Section 3.9.2 of NDS 2005 Edition applies to wooden poles. Please see a copy of the NDS code. Is this equation for stability or member strength?
I am analyzing a guyed tower that rest on a 6' diameter by 50' deep drilled caisson. The major forces applied to the foundation is the down force and some minor shear force. The pier has only (18) #6 bars, which is not even close to 0.5% required by ACI, but since there is virtually no moment in...
I am working on the foundation reinforcement design that currently has a few rock anchors holding it in place, we need to add more micropiles (3" dia. DYWIDAG 150ksi bar). The original foundation drawing is pretty vague and does not have specs shown for the anchor rocks or the grout used...
I am working on a design of a transformer foundation. Transformer contains 1050Gal of oil. That is quite a bit of oil, that would require 146 cu. ft. of containment volume around the transformer pedestal, if I add crushed stone into the pit, it will quadruple the volume.
I have an option of...
It is typical for geotech reports advising to ignore top 3' or a full pier diameter for soil skin friction capacity and such. But if you want to reinforce that drilled pier with a cap, you can place it within that 3' depth, as long as you can place it on soil with adequate bearing capacity...
Per D.6.2.1(b) shear force perpendicular to the edge on group of anchors is Vcbg = Avc/Avco*(********)Vb
where Avco is the projected area for a single anchor in a deep member with a distance from edges equal or greater that 1.5Ca1 in the direction perpendicular to the shear fore...
dhengr
the part from "Pressure Vessel Design Handbook" is all I found as a reference. Not sure what codes are applicable to the tank, silo design - as we deal more with the design of platforms for industrial applications. The reason for which I need to know what purpose "Support Skirt" serves...
This interesting discussion prompted me to look for more references, and I found "Pressure Vessel Design Handbook". It categorize the lower portion of the shell as "Support Skirt" and gives formulas for stresses, however it ignores the column load capacity which seems too conservative. See...
what sort of cross bracing? a horizontal brace from column to column? What if the opening will have a stiffener ring perpendicular to the tank plate? Will it serve as a load transfer mechanism?
dhengr
The tank/silo is already built. We just need to design an observation opening around 10' elevation in the steel plate. That is why I wanted to know what purpose the plate serves on the lower portion of the tank.
to dhengr
Yes, the columns are inside the tank. so they go from ground all the way to 80'. the silo has a drive-trough opening, with two moment frames on each end. from 80' to 50' I assume the serve as tank stiffeners. It seems to me that that the plate around the tank columns below 50' would...
I have a 106' tall by 32.5' diameter tank. It has a hopper that starts at 50' elevation and goes down 23' and has a 7' diameter opening. The tank has 22 W-shape columns that extend only up to the elevation of 80'. the thickness of the tank plate is 3/16" from top to about 80' and than it...
