Hi,
I have a slab on grade 8'' thick and it will carry heavy vehicle loads, I have specified 15M rebar @ 12'' c/c in each direction. My client is asking me to provide an alternative using fiber steel reinforcement. My question is, how do you calculate it ? what would be the equivalent to 15M ?
Hi,
I have an existing 6 inch slab on grade. I want to know if it can support a linear loading. The equipment that I have to support sit on a steel "W" beam width of 5 inch. The load carried to the slab is 25 kip /ft.
How do you evaluate if the slab can carry such load ?
Thank you for helping
Hi,
I have a concrete tank 4 feet underground. On the top heavy vehicles are present (air plane). The concrete wall tank has an height of 5 feet.
How do you determine the moment acting on the wall ?
Vehicle load (aireplane): 24 000 psf
Hi,
I have a verification to do on a traffic light truss (span of 90feet) The truss is made of 6061-T6.
What will be the value of the Fy for the calculation? Will you use a value of 35 ksi or will you consider it welded and reduce it to 15 ksi ?
Hi,
If I have a slab 6in thick on a soil with Kwinkler = 100 pci and a live load of 150 psf.
How do you evaluate the ground stress and the slab concrete stress ?
Thank you,
SilverBeam75
Hi,
I have a one story URM building that I have to analyse using ETABS. How do you model the walls in ETABS ?
The unreinforced masonry consists of 12'' hollow concrete blocks. If I use a SHELL element of 12'', it will act as a plain concrete wall, what do I need to change to have an...
Hi,
In seismic design, it is required to have a mass participation ratio of 90%+. My model has 75%, what should I do to increase it ? What exactly does it means?
Any help would be appreciated
I have two (2) anchors with a distance of 8'' between them and it is installed on a 12 in wide strip concrete wall. The anchor embeddement is 12'' deep. I've used a software for anchor analysis and it indicate a PROJECTED AREA FOR GROUPS OF ANCHOR "An" 77.5 in^2. I'm unable to verify it. What...
Hi,
I'm using SAFE 12, and I have a hard time trying to model a slab on expansive soil. I have an uplift linear load only on the perimeter beam of the slab. The super imposed dead weight is not enough to counter the uplift pressure. I have defined a spring value (compression only) and my load...
Hi,
I have a concrete beam on soil (expansive, uplift pressure)
Span = 30 feet (ends fixed)
if My loadings are (plf - pouds per linear feet):
WLu = 1500 plf (uplift load)
WL = 500 plf (live load - gravity)
WD = 600 plf
What if the load combination and what will be the factored linear load...
My project involves to build a new steel structure for an elevator which will be attached to the existing structure. Each node which will be attached I would like to model it as a spring. But how do you evaluate the stiffness of an existing structure ? If I design my structure without any...
Hi,
I have an aluminium pole section (4x4x0.25) 24ft high with a 12" cantilevar fixture that will hold the lighting. I need to find the maximum EFFECTIVE PROJECTED AREA (EPA). Do I need to find the the maximum EPA versus the strenght of my pole or is it a limitation of displacement of the pole...
Hi,
I have a vibrating machine (440 RPM) and the weight of the machine is 45000 lb.
How do you design a concrete mat, I've seen the ACI 351.3R-04 (Foundations for Dynamic Equipment) but I cannot figure where you calculate the slab.
Anyone has a design guide (tutorial) ?
thx for the help
Hi,
I want to model a tension only X brace. I've seen the FAQ http://www.eng-tips.com/faqs.cfm?fid=1169 but I guess it was done with an old version of ETABS. In ETABS 9.7 it is not possible to assign a frame to NONE.
Anyone know how to model a tension only X brace ?
Hi,
After performing my seismic analysis. I see that in MODE 1 my structure has torsion. When I look at a point modal component I get a value for:
Trans and rotn, but what exactly are these values and do they have a unit ? I'm guessing TRANSLATION and ROTATION. What exactly does it mean, how...
Hi,
When you design an isolated footing, the area required (based on the bearing capacity of soil) is using the unfactored gravitary load. But my analysis seismic analysis indicates that I have a pressure load up to 6-10 times my gravitary load. How exactly do you design the footing. I guess...
Hi,
I do not have the Roark's book...and I need to evaluate the thickness required for a 5'x5' steel plate A36 simply supported on all edges. My load in the middle is 33 kips. The maximum deflection permitted is 0.25 in. How can I evaluate the thickness required ?
What is the formula ?
Thank...
Hi,
Not very familiar with the FRP (carbon) plies. My project is to cut several holes (approx 20"x6") in an existing concrete slab (8" thk) with 15M @ 12" o/c ea. direction.
I will need to add FRP plies around the hole. But what is the methodology, how to approach such problem ?
If I consider...
Hi,
I've to design an outdoor (temporary) stage structure. The dimensions are: 70' x 53' x 45' high. The roof is covered with a dense fabric (kevlar type) and the rest of the structure we use a mesh type shade.
I know that if I have fabric around 3 faces and my downstage is left open the wind...
