Hello,
Does the ASCE7 or IBC anywhere mention that instead of using the special moment frame, we can use the ordinary or intermediate moment frame if we use a lower value of R and therefore, design for higher forces ? Does anyone know if such thing is allowed by the code or not ?
hi all,
In the punching shear calculations for a suspended slab, a column near a discontinuous edge is considered interior if the distance from the face of column to the edge exceeds 4 x slab thickness.
Is the same applied for column resting on a foundation ? Should the foundation be equal...
hello,
i have a one story builidng which i am investigating if a cantilevered column system is better than special moment frame. the seismic design category is D.
i guess no requirement for beam column joint. asce7-10 specifies that it must be detailed to fit the requirements of SMRF.
Does...
hi all
It will be the first time I use the special moment frame in order to stabilize the building consisting of 2 floors I am working on. I am reading some literature about this topic. One of the questions which comes to my mind:
If there is a possibility to add some walls here and there, will...
Hello I am a structural engineer with an experience of 10 years.
I would like to shift my career towards construction management.
However, all the opportunities found require 10+ and 15+ years of experience in the field.
My question where should I start? And is such transition possible ? Will...
Hello,
i would like to have your opinions regarding section 10.10.2.1 of ACI318-11 where it states "Total moments inluding second-order effects in compression members , restraining beams, or other structrural members shall not exceed 1.4 times the moment due to the first order effects" if it...
Hello,
I am designing a slab on grade of an industrial warehouse where some high uniform loading will be located and forklift circulation is expected daily.
The slab on grade is 100x100 meters and will be separated from the concrete pedestal by isolation joints. The concrete pedestals are...
hello,
I would like to ask your opinions about torsional stiffness reduction for beams.
A lot of engineers use a low torsional constant (J = 0.1) in order for the beam torsional moment to be transmitted to the slab, in case of compatible torsional system.
however, despite assigning a low...
hello,
i would like to have your thoughts regarding the below.
i have a new small structure which will serve as extension for an existing old building.
The contractor is very clear regarding the fact of avoiding all types of column / foundation jacketing.
Therefore, i am adding new columns...
Hello
I would like to take your advise regarding a stepped foundation I am facing.
2 different thick raft are being designed each one located at a different level.
The level difference is 7 meters between the top and bottom mat. At columns location a thick pedestal is being considered.
The mat...
Hello
Whenever u have a very slender reinforced concrete wall rising many floors without any lateral bracing (core elevator for example - H shape having its web braced at the ends but nothing in the middle and the web is quite large in plan), how do u treat such element versus buckling ...
Hello
What is your common practise of extending reinforcement foundation rebars? Do you use the same bars extension defined in chapter 13 the aci and consider the foundation as an inverted slab?
In other words do you extend your bottom reinforcement 0.3/0.33 of the span and the top...
Hello,
A flat slab carrying some amount of fill is being designed. An opening is to take place and reinforced concrete parapets around the opening are in place to avoid for the fill to come.
When designing such a slab for punching and for the columns located at a distance less than 10 x slab...
Hi,
I am facing a problem with a circular concrete watertank which is leaking (diameter around 10 meters and height around 20 meters).
Many longitudinal cracks are visible from the exterior.
No as built drawings for the stucture are available with the client.
The cracks measured looks...
Hello
I have a raft supported on piles. The cur off level of the piles was based on a thicker raft. However the raft got reduced.
To make it short the embedment length of 50xbar pile diamter is not ensured. So the contractor is willing to break the top of rhe pile and splice the old reinf'f...
Hello i have 2 questions regarding flexural bars extension according to aci318
1- does the slab bottom reinforcement needs to be terminated by a hook at the discontinious edges ? I would vote for 150mm bar extension into support is enough but there is this section which puts limit on the bar...
ASTM 615 dealing with steel reinforcement specifications specifies the required yield and tensile strengths (fy and fu respectively) as well as elongations.
If the grade is 60, fy (min)= 420MPa; fu (min) = 630 MPa (fu/fy=1.5).
If the grade is 75, fy(min)=520Mpa;fu (min) = 690 MPa(fu/fy=1.33)...
Astm 615 dealing with steel reinforcement specifications specifies the required yield and tensile strengths (fy and fu respectively) as well as elongations.
If the grade is 60, fy (min)= 420MPa; fu (min) = 630 MPa (fu/fy=1.5).
If the grade is 75, fy(min)=520Mpa;fu (min) = 690 MPa(fu/fy=1.33)...
Does the aci318 specify any upper limit of bars reinforcement ?
The thing is that i have the contractor which is proposing to use steel reinforcement of fy>1000Mpa in some concrete elements ?
The thing is that i think i wont have anymore a ductile.section since concrete will crush ans steel...
1 - When dealing with the design of a retaining wall, why some engineers prefer not to mobilize all the passive pressure ? Is there any rule or it is just a way to be conservative ?
2 - if the retaining wall is long enough in plan and an expansion joint is introduced every interval, does the...
