Wind load acting on the flagpole

E

eissenhover

New Member
Hello friends. Whenever I'm stuck, I stop by here :) . I have a question. I want to blow the wind on a 55 meter flagpole. The foundation will be reinforced concrete, and the pole will be of circular cross-section, with a base diameter of 120 cm and a top diameter of 25 cm, which gradually narrows. According to the calculation rules in TS498, I want to affect the maximum wind load value such as 2.08 kn/m2. In İdecad, I am designing the pillar by anchoring a hollow pipe profile on a reinforced concrete foundation. (Unfortunately, since idecad does not have a variable cross-section profile, I bought 120 cm from the bottom to the end of the current pole). When I want to add load to the pole, the options that come to me are in kgf/m since I put it in the steel column menu while placing the pole. but the wind load in the regulation is in ../m2. If the construction in question is not a pole but a roof covering, there is no problem, but in this way, how can we add a load in m2 to the pole style elements.
 
Re: Wind load Since you can't create the variable section you want to do, how close will it get you to load the fixed section and see the result? It is not right to push the limits so much just because of the steel program. I think what you need to do is to create the real section with finite elements, load the wind loads with pressure on one side of the section and suction on the opposite side, interpret the section effects and displacements and perform the design in programs according to purpose and need such as sap 2000, staad Pro.
 
Re: Wind load first of all thanks for your reply. I will not prepare an application project by using the same section throughout the drek. I'm just looking for a way to solve such a structure in Idecad. I can solve this account manually without using sap2000. The aim is to see if it is possible in Idecad. Because I cannot apply a load in kn/m2 to the dire that I define as a column in Idecad. It offers the possibility of loading a vertical load. Here I am trying to question how accurate solutions are, such as multiplying the wind load with a radius and converting it to kn/m and affecting the dirge.
 
Re: Wind load It is currently not possible to define a bar element with variable cross section in ideStatik. I also requested that this feature be included in the software in future versions. Currently, in the software, a 55-meter-high bar element can be divided into many pieces of equal length, and a different pipe profile section can be assigned to each piece and modeling can be made for an approximate design. As you increase the number of segmented parts, the results you get will get closer to the results of a modeling that can be done with a variable section. In order to stay on the safe side in such a modeling, it would be better if the pipe section section you assign for each sectioned bar is the smallest diameter of the variable section corresponding to that section along the length of the relevant bar. You don't need to build and calculate this pole with finite elements (shell elements). It will be sufficient to define it with a stick model. You can use the 7.xx articles of the TS EN 1991-1-4 standard or the ASCE 7-10 article 29.5 to define the linear wind load, which will affect the bar profile and change its value at certain heights (both due to pipe diameter and height), Since it contains design information directly for this type of building elements, it will make healthier directions. dynamic effects etc. Assuming that the effects will be taken into account in addition to this, you can get the linear load values that you can calculate by multiplying the m² load you have determined with the drag coefficient (drag coefficient, unitless) and the pipe diameter, the value of which is 1.2 for circular sections. You can make an approximate calculation by defining these values separately in ideStatik as linear loads calculated with their respective diameters to the segmented bar elements. Especially since a 55 meter long steel profile flagpole requires a design that needs serious consideration, I suggest you consider the specific reference "ANSI/NAAMM FP1001-97, 5th Ed., Guide Specifications for Design of Metal Flagpoles". It would be appropriate to make an integrated design in which the aerodynamic load coefficient of the flag, which I predict will be large with the dynamic effects of wind loads, is handled and the dynamic responses of the mast (resonance, etc.) are also examined.
 
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