Fatima Khalid

Asalamualaikum

Why some engineers put reinforcement in top and bottom? They used to put same bars in top and bottom of footing.. What can be the reason?

Asalamualaikum

I am designing ground+1 240sq yard residential bungalow.. Stair plan is attached.. If i take flight#3 (marked as f3) as simply supported then thickness comes out to be 11"... so do we provide that much thickness for waist slab?? 

or should i make flight#3 to rest on landing at elev 6'6" and elev 11'6" and adding point load on flight#2 to reduce slab thickness?? 

Thankyou

Thank you for sharing the sheet and relevant material

Any sheet/pdf for design of concentric and edge footing tied with strap beam?

Wa alaikum us salam,

I dont have any relevant info regarding similitude study but I found your research topic very interesting. By the way, Are you going to consider effect of infill walls as well? Best of luck. 

It is easily available on Scribd.. 

use PEER NGA website to extract groundmotions data.. 

Its Opensees: Open System for Earthquake Engineering Simulation.. A finite element program used for research purposes

I think you should not make your beam inclined in the last figure. Instead you can rest your beam on left beam by making it straight so the load from that beam will ultimately transfer to column. 

Shake table test for Buckling Resistant Braced frame is conducted in NEDUET today at Department of Earthquake Engineering.

Thank you for detailed reply

How to read seismic fragility curves?  I have attached a picture of a fragility curve taken from internet. Assume it is for low-rise buildings, so what does it show?

Example: If an earthquake of 0.6PGA occurs, then there is a probability 25% building will experience extensive damage (h=7.5m), 55% will experience moderate damage and 90% building will experience slight damage. Am I right? 

Does it mean that if there are 100 buildings, then it means that 25 building will damage extensively, 55 buildings will have moderate damage and 90 buildings will experience slight damage. But 25+55+90 is not equals to 100. 

Please explain how to read fragility curve?

Thankyou

to calculate participation factor, you first do modal analysis.. from first mode.. take the eigen values that would be the mode shapes at each storey... Take storey mass of each storey and solve it manually or using excel file..

By the way, if you want performance point, you can directly get from the SAP result where it shows caapcity and demand spectra. See the attached research paper for ur reference

IRJET-V3I5479.pdf

Asalamualaikum all,

Is there any software which can calculate area under the curve if I give the co-ordinates of curve instead of equation?

• M11: Direct moment per unit length acting at the mid-surface of the element on the positive and negative 1 faces about the 2-axis.

• M22: Direct moment per unit length acting at the mid-surface of the element on the positive and negative 2 faces about the 1-axis.

How can I reduce shear racking??? Is there any method from which I can make a frame having shear force greater in bottom storey column then in first storey column?

Is shear racking phenomenon is valid for any frame? Like if I made 3 storey 2D frame, then the distribution of shear is correct but if i made 5 6 or 7 storey frame, the same thing occur..

Thank you Sir for such a great explanation and detailed answer. Thanks alot

i know this.. Anyway Thanks but my question was why middle columns are attracting more shear at first storey as compared to base??

yes..

This is just a frame analysis. I have checked it in SAP and GRASP as well..  But same things happens. Shear at 1st storey is more than shear at base..

model1.$ET

I have made a frame. Lateral Point Load is applied on each storey. Attached is the picture of frame. Why shear force in internal column of frame is more in 1st storey as compared to bottom storey?

Thank you all for the help

Thank you Sir

If concrete fc'=17.82 MPa, is there any relation from which I can find its fracture energy?

I have seen CEB-FIP codes, they give the fracture energy with respect to aggregate sizes. I dont have aggregate size for my concrete. Now when I am doing finite element modelling, so I require fracture energy. Is there any approx. values of fracture energy with respect to concrete strength?

Thank you

See this document, Hope it helps.

Web Technical Note 2-Meshing and FEA.pdf

Thank you EngrUzair and Baz