Building Analysis with Natural Frequency according to self Mass and Weight: Building Structure: Roof color Beam color keypoint color 1 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] This is important thing we must do, Changing Job Name is the better way to save our work later without any problems. Hint: Sometimes, some windows disappear, so click on this icon Enter the Job Name you want. And Pick Yes for new Log error file this is good for Session Editor. 2 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Preprocessor: Choosing structural to update all mechanical and physical properties such as Loads, stresses .. etc. 3 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] In structure we have many Element types, first we choose Structure Mass – 3D mass 21, this is because we want to analysis the building according to its Mass. Then we choose Beam – 3D Finite strain or 2 node 188, because the Lines in the construction of this building take the Beam Element. Shell – 3D 4node 181, for Roofs 4 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Combination – (Spring – Damper) we add this Element Type to the building because we want apply Natural Frequency according to the Mass of building (Spring – Damper) element type makes Natural Frequency and frequently motion like pull and push without any external force. 5 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Select for structural Mass element type, from Options (3D w/o rot inertia) means we don’t need any rotation in the mass, just concentrate downward. 6 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Add Real Constant for Mass : enter the amount of mass for FLOOR let us say (50 kg), then Apply. Enter the amount of mass for Beam because it is different from Floor let us say (30 kg), then OK. 7 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] We must enter Spring Constant according to any problem, we take it here = 2500, also if there is Damping Coefficient, this is OK, but here we don’t have. Also we have to set the Real Constant Set No. as we wish, here we take it = 3, because this will help us in Mesh Attribute. Real Constant for Combination No Real Constants for Beam and Shell At last we get this 8 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] We will Add material properties later, (this is up to you), but now we will complete the modeling. 9 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Change view and you will get these Keypoints These represent the ground keypoints 10 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Now make a Copy to the keypoints Pick the four keypoints then Apply No. of copies: includes No. of original keypoints set + any No. as you want, here we select 2 sets to be easier to connect with Lines later Enter 4 , distance on Y-axis 11 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Click Fit to see the keypoints Pick OK 12 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Connect the keypoints to get the first Floor (Storey) After you complete pick OK 13 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Repeat same procedure, Copy the upper keypoints and do as in the fig. 14 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Click Fit again you will see only keypoints. 15 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Select Multi-Plots 16 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] You will get this 17 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Repeat same procedure, Copy keypoints and Connect with Lines until you get this. 18 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Make the Floor Area. By Arbitrary – By Lines, select only four Lines then Apply. 19 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Repeat same procedure Floor after Floor, until you get this. 20 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Now we reach the IMPORTANT step, means adding other keypoints for Spring Element represent the (Natural Frequency), these keypoints must be drawn at the same height of top Floor, so make Copy for any two keypoints on same side on the top Floor at any span you want 21 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Now connect these two points with Lines 22 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Enter two difference properties one for the Beam another for Floor. 23 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Choose any Section for Beam and fill as in the Fig. remember ID = 2 because it is Carbon 24 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Enter Shell thickness, means Floor thickness. Remember ID = 1 , because it is Aluminum . OK. 25 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Apply Mesh Attributes, first for Areas, but attention it is very critical to select the suitable properties and Real constants as in the fig. Material No. = 1 (Aluminum) Real Constant = 1 (Mass = 50kg for Floor) For Picked Areas we choose Shell, and already it will take the Mass Element Section for Shell, thickness = 0.25 called Floor 26 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Select All Lines except two Lines for Spring as in the fig. Material No. = 2 (Carbon) Real Constant = 2 (Mass = 30kg for Beam) For Picked Lines we choose BEAM, and already it will take the Mass Element Section for Beam Dimension = 0.25 * 0.25 called Beam 27 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Select these two Lines No matter select 1 or 2 , this will not considered because of combination Real Constant = 3 (K = 2500 for Spring) For Picked Lines we choose COMBINATION No matter select any thing , this will not considered because of combination 28 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Now select All the keypoints that you want to show the concentrated Mass on it, I picked All keypoints at the corners except at the ground and at the end of Spring as in the fig. Material No. = 1 (Aluminum) Real Constant = 1 (Mass = 50kg for Floor) For Picked Keypoints we choose MASS 29 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Select Manual Mesh and mesh the two Line for Spring No. of Division = 1 this is to get Natural Frequency as Dinesh said. (we can enter another numbers but this won’t give us Natural Frequency) 30 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Mesh remaining Lines No. of Division = 10 31 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Mesh – Keypoints : Select All keypoints except at ground and at the end of spring. This is important to make a relationship between analysis of Shell (Floor) and Beam. 32 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] You will get this 33 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
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[email protected] Mesh – Lines : pick Line by Line (each Line) but don’t use the command (Pick All) 35 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] 36 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Apply Displacement constraint on keypoints at ground only, All DOF 37 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Apply self-weight (depending on Mass) : Structural – Inertia – Gravity – Global, then enter (9.81) with Y-axis 38 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Yes 39 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
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[email protected] Until now we complete first stage of our work of drawing Natural Frequency, we must press Finish before we enter the next stage. 41 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] In the previous examples we analyze as a Static (means any geometry with static load), so when we want to post to next stage such as Modal , we have to finish our work as a Static (like we just done) then introduce to choosing the Modal, (same procedure must done if we want another types in the window below) Static : Any shape with static loads. Modal : Any shape with self-weight and natural frequency. Harmonic : Any shape with external force. Transient : Any shape analysis with respect to time. Spectrum : Any shape with respect to crack propagation. 42 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Analysis Options : this window for setup motion of frequency like up and down (all these options for choosing the shape of frequency) and where it should affect .. select (Block Lanczos) if there is no solution select (PCG Lanczos) they give same work. Enter 10 for example, means the No. of Nodes that expose to the extraction of Frequency Enter 10, means the No. of Nodes that expose to the expansion of Frequency Pick Yes Pick OK Frequency start from 0 unit Frequency end at 10 units Select To unity for better frequency as Dinesh said 43 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Pick OK 44 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Pick (First Set) nothing happen but the Ansys understands that we want Read and Plot the first set of NODES in the drawing, means first motion how it’s look like. 45 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] First Set give us the following deformation 46 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Pick (Next Set) nothing happen but the Ansys understands that we want Read and Plot the next set of NODES in the drawing, means next motion how it’s look like. 47 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] And so-on, but for better and real view activate the Animation, and you will see the real Natural Frequency. 48 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] TimeHist Postpro: from appearing window we can setup a graphs like between Time and Distance. Pick Add Data For example select DOF solution with X-axis 49 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] I select this keypoint Drag this window and select any keypoints or any element in the drawing. Pick OK 50 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] Pick Graph Data, means the change of Distance with Time for this keypoint. You can see here the Time always appear, and below is the chosen type for graph Note: since we are in Modal study then we can graph Time with Deformation only (UX, UY and UZ), when enter to Harmonic we can graph with Stress, as Dinesh said 51 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
[email protected] This is like scientific calculator if you need it to solve any equation you can use it, and (maybe solved equation can used in the graph) as Dinesh said. 52 | Haydar Alsalami \ JNTUH \ India mobile: 00919059070644 – Iraq mobile: 009647801518389 E-Mail:
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