Gus14
Your question is very valid and needs to be addressed in design.
In all practical designs of combined footings, this problem exists.
First of all, the actual loads may be different from the estimated loads.
Secondly, we design for the worst combination of loads only. The loading...
The easiest way to do it manually is to use Moment distribution. With only two spans, you need only two cycles, viz. one balancing + one carry over and another balancing. (I presume that the extreme ends are simply supported).
You only have to obtain the Fixed end moments and the shears for the...
As a structural engineer who worked for 36 years in the design engineering of buildings, power plants and process plants, I consider the following as the inherent and unavoidable hurdles for a civil/structural design engineer.
1. The sequence of engineering activities of plants is as follows...
I feel that there is no need for considering beam, column combination for this structure, though it is another way of supporting the structure.
The slab portion covering the balcony area can be treated as a simply supported span with an overhang. Since the walls are of masonry, there will be...
I agree with rb1957.
It will hardly take a few minutes to get the equation for the deflection at any point using double integration/McCaulay's method.
equating the slope equation to zero, the location of max. deflection and thereby he max. deflection can be found.
Will your architect allow to provide flange plates? If so, you can transfer the compression and tension from the flanges of the cantilever to the supporting beam on the other side by welding flange plates through the connection at the top and bottom. The web connection can be a shear connection...
The two phenomena are explained through a spring-dashpot model with the spring and dashpot connected in series for one case and in parallel for the other.
Rapt
I am not clear about your statement 'Relaxation in prestressing steel is tensile creep'.
Please correct me if I am wrong.
From my basic knowledge of Material science, Creep and relaxation are two different phenomena.
Creep is the continued deformation under sustained constant laoding and...
BA is right. There is no fixed or pinned footing.
The fixity is between the column and footing only. If the column is fixed to the footing, it transfers axial load and moment to the footing (along with any horizontal shear). If the column is pinned at the footing(which is normally done in steel...
Thank you guys.
JAE, Prior to starting this thread, I have almost concluded to your suggestion of doing the design by hand from first principles. You have reconfirmed it.
I do not have the PCA software but I can try to get it.
Ishvaag, I will also try to understand the method given in your...
Thanks for the responses from all.
I must apologise for not making my query precise.
The building is a three storeyed structure octagonal in shape.
The columns at the corners of the octagon receive beams from either side of the corner of the octagon.
The columns are 12" wide 24" along the...
I am invoved in the design of an octogonal shaped RCC building.
Is there a design procedure or a handbook to design V shaped RCC columns (with an included angle of 135 deg.)?
Thanks for the help
Trilinga
I have to support an equipment on a structural frame resting on a set of existing roof beams. The lateral deflection of the frame consists of two parts, viz. the lateral deflection of the frame and the additional lateral deflection due to the differential vertical deflections of the supporting...
I am not familier with writing of Macros in EXCEL.
I have an Excel spreadsheet in which I have data of different categories identified through different colour fills in the respective cells.
If I have to count the number of cells with a specific category, is there any option in countif command...
It is a normal practice to tie the pile cap in the direction along which no lever arm is available to resist moments.
In a pile cap with two piles, the moment in the plane containing the two piles is resited by the push-pull on the two piles.
The other direction has no such capacity. The tie...
Reinforcing the tension zone is one critical aspect.
The second is the availability of sufficient counterweight for balance. If the slab is not continuing to a reasonable length on the other side if the masonry wall, the shuttering for the slab (particularly the props) should not be stripped...
I find the equation can be made simpler by equating the energies.
The energy of the falling object as it strikes the beam (at the centre to be conservative)is 'mgh'.
Neglecting the losses due to impact (again to be conservative), this energy is stored as the strain energy in the beam while...
Sorry for my delayed response. My PC was down for a few days.
Thanks for the enthusiastic response of all.
I infer from these posts that it is desirable to design the footing as pinned.
Maybe, I need to revisit my concept of fixity for a footing.
However, I think we should not forget the...
