Пікірлер

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  @AidilSafutra2 күн бұрын

  is it okay, define eartquake load for combination using eartquake static ekuivalen?

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  @tolist-k1w9 күн бұрын

  hello, how to define in Etabs that the bracing of my building is provided by concrete frames when we don't have reinforced concrete bracing wall? should i release moments at the start and end of columns or at the start and end of the beams ? the bracing is provided by free-standing reinforced concrete portal frames

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  @Eng.tarekyoussef8 күн бұрын

  To accurately model the behavior of the portal frames as bracing elements, you typically release moments at the ends of beams where they connect to columns. This approach acknowledges that the beams are hinged (or nearly hinged) at their ends where they meet the columns (not at the start and end of the columns). The decision to release moments depends on the structural design and the intended behavior of the portal frame system under lateral loads. If the frame is designed assuming hinge behavior at the beam-column connections (for example, for moment redistribution under lateral loads), you release moments. If the design assumes rigid connections to transfer moments and shear without significant rotation, you do not release moments. In summary, you do not necessarily release moments to all beams in all types of portal frame systems. It depends on the type of the beam-column connection (fixed or hinged connection).

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  @muhammadkareem128420 күн бұрын

  In 12:14 How you know to use this equation to find Cs where is or much TL to compare with t?

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  @johnybroo49420 күн бұрын

  Where are u from

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  @muhammadkareem128421 күн бұрын

  In 6:58 If different between cm and cr exceed 5% what will we do?

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  @towhidurrahman896128 күн бұрын

  Very Nice tutorial. But I want to know the very basic. Can you tell me, how can i calculate the lumped mass matrix and consistent mass matrix and stiffness matrix for a 3d space frame? Should i apply the gravitational load(such as dead load, live load, partition wall load etc) for calculating lumped modal mass matrix and consistent mass matrix? can you give me any link or anythng else that solved a full example ? Thanks.

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  @moh.rizkypradana2775Ай бұрын

  sir, what if the P value in story force is empty? is there anything that needs to be added? please confirm sir

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  Ай бұрын

  Why it is wrong if the mass is not lumped at the floor level. In fact there are two different mass matrix coupled and uncoupled or lumped and consistent. With shear walls mainly the consistent mass matrix is likely to be correct because the mass of vertical elements slightly smaller than or equal the mass of the floor then there is no point to lump the mass at the floor level.

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  @Eng.tarekyoussefАй бұрын

  ETABS does not lump the masses correctly to floor level if the mesh option for shear wall is used. This issue is also announced through the CSI website. In reality, the mass of a building is not only concentrated at the floor levels but is distributed throughout the structure. Lumping masses at the center of each floor, which is done by the use of a rigid diaphragm, is an approximation to simplify the analysis. Thus, the mass matrix generated in ETABS will be affected by the way the masses are lumped.

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  @HudaAl-KasasbehАй бұрын

  Thank you very much

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  @Eng.tarekyoussefАй бұрын

  You are welcome

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  @muhammadsohailhussain849Ай бұрын

  Could you brief the behaviour of modifiers for the bearing wall system please. They don't go under crack or non-cracked just for gravity

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  @Eng.tarekyoussefАй бұрын

  In a bearing wall system, the walls primarily carry vertical loads, known as gravity loads. So, when considering modifiers for such walls, it's important to assume an un-cracked section, as cracking can occur due to gravity loads alone, even without considering lateral loads. This ensures that the design adequately accounts for potential cracking under gravity loads.

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  @muhammadsohailhussain849Ай бұрын

  Loved it, Cleared my Concept, Thanks, JazzakAllah

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  @Eng.tarekyoussefАй бұрын

  You are most welcome

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  @Aussie_EngineerАй бұрын

  Superb 🎉

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  @Eng.tarekyoussefАй бұрын

  Thank you

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  @mohamedsamer1052Ай бұрын

  At design of shear wall, after checking cracks on wall ,is be enough to change the modifier of the zone that exceeded the limit and continue the design or we should make shear wall safe from any cracks?

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  @Eng.tarekyoussefАй бұрын

  In practical design, it is challenging to prevent all cracks in a shear wall. Minor cracks are often acceptable and expected due to the nature of concrete and the stresses it undergoes. When cracks exceed acceptable limits, one common approach is to adjust the stiffness modifier of the affected zone. This adjustment helps to account for the reduced stiffness of the cracked section and provides a more accurate representation of the wall's behavior. While these modifiers offer a practical solution, they may not always be entirely accurate, particularly in capturing highly nonlinear behavior. Performance-Based Design (PBD) allows for a detailed understanding of the nonlinear behavior of structural members. This includes evaluating the level of nonlinearity and determining whether the wall is performing safely despite cracking. Linear vs. Nonlinear Analysis: 1- Linear Analysis: In linear analysis, the material is assumed to remain within its elastic range. This assumption limits the ability to accurately assess cracking and nonlinear behavior. For regular buildings, linear analysis is typically sufficient, as it provides a reasonable approximation of the structure's response. However, it may not capture all aspects of cracking and nonlinearity. 2- Nonlinear Analysis: For irregular buildings or those expected to experience significant nonlinear behavior, nonlinear analysis is essential. This type of analysis captures the real response of the structure, including the effects of cracking and stiffness degradation. I hope I answer your question

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  @Osama-Anwar2 ай бұрын

  Hi Tareq, Great tutorial. I am designing a buiding with extreme torsional irregularity having seismic design of D so I can't use ELF. Governing mode is of torsion. Should I define RSA for RX, RY and RZ? How and where?

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  @Eng.tarekyoussefАй бұрын

  When designing a building with extreme torsional irregularity and a seismic design category D, it's crucial to account for the torsional effects accurately. Since the Equivalent Lateral Force (ELF) procedure is not suitable due to the complexity and irregularity, the Response Spectrum Analysis (RSA) method could be appropriate, but the NLRHA is the best ! RSA in X & Y Directions: You need to define RSA load case for X and Y directions. RSA in Z Direction (Vertical RSA): In most cases, RSA for the Z direction is not necessary unless specified by your building code or project requirements. Vertical seismic effects are generally less critical than horizontal effects for typical buildings. However, if your specific code or project requirements mandate it, then you must include RSA for the Z direction. Understanding Torsional Effects: The torsional irregularity is primarily due to the asymmetric distribution of mass and stiffness within the building. This causes the building to rotate about its vertical axis (Z-axis) when subjected to lateral loads. Improving Building Response to Torsion: Adjust the location of structural elements such as columns, shear walls, and bracing to reduce torsional irregularity. Aim for a more symmetric distribution of stiffness and mass. Summary: 1- Define RSA for X and Y directions to accurately capture the lateral seismic response. 2-Define RSA for Z direction only if required by your building code or project specifics. 3-Focus on torsional analysis to understand rotational behavior. 4-Adjust structural configuration to minimize torsional effects, ensuring a more uniform distribution of stiffness and mass.

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  @shareqinamdar89032 ай бұрын

  Informative

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  @shareqinamdar89032 ай бұрын

  Good explanation

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  @Eng.tarekyoussefАй бұрын

  Thank you

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  @shareqinamdar89032 ай бұрын

  Informative

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  @khai_8962 ай бұрын

  Good

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  @TA3A.YAWARD2 ай бұрын

  Hi Tarek, Could you please explain to me then how the accidental torsion it will be account in the RSA? since the amplitude it is just a displacement in x and y. and the accidental torsion will create a torsional effect !

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  @Eng.tarekyoussef2 ай бұрын

  kzread.info/dash/bejne/e6dm2NSBfMiZdJM.htmlsi=mKcNeRqQiG_a8sbK

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  @TA3A.YAWARD2 ай бұрын

  @@Eng.tarekyoussef yes I am aware of the two method the issue is if you want to check the torsional irregularity in response spectrum you simply cannot

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  @AhmedMutaher-ft7kk2 ай бұрын

  Thanks alot

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  @TokyoSoloRider3 ай бұрын

  When you are good at something, you can present it well.

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  @Eng.tarekyoussef3 ай бұрын

  Hope you enjoy it

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  @TokyoSoloRider3 ай бұрын

  Very nicely explained. I loved it!

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  @TokyoSoloRider3 ай бұрын

  Thank you buddy for the valuable lecture.

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  @husseinibrahim12283 ай бұрын

  Very clear explanation, 👌

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  @pedjamarkovic66763 ай бұрын

  Very good explanation ! Thanks for sharing!

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  @Eng.tarekyoussef3 ай бұрын

  wlc

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  @zuhairdema3 ай бұрын

  Dear Engineer its allowed for the building to be bigger than the other stories,,, as i see in your model there’s a five story as basement extended then 8 stories smaller then the rest of the tower is smaller in area it’s acceptable,,, since i guess its not allowed and you should have an expansion joint between the tower and the rest of the story if they are bigger in elevation

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  @Eng.tarekyoussefАй бұрын

  Thank you for your observations. Here are my clarifications regarding the structure: No Basement: In this project, there is no basement; all stories are above ground. Irregular Building Design: This building has an irregular shape. While using expansion joints can enhance the structural response, the current model was studied without expansion joints to understand potential issues within this system. High Load Transfer at Podium Level: In such structures, significant load transfer occurs at the podium level, especially where there is a change in the floor plan layout. If this building were to be constructed, we would add expansion joints. This would divide the structure into several pieces, thereby reducing the intensity of the transferred forces at critical levels.

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  @hamedoelnagdy45943 ай бұрын

  why we should not use cd factor when check drift with Resposne Sp.????

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  @ahmedjameel4578Ай бұрын

  because the res spec load case has to include the ratio *I/R. the drift load combo has to include Cd/I. So he merged the two cases and just multiplied by (I/R)*(Cd/I) which is Cd/R = 5/6 = 0.833. In the ELF method there is no inclusion of these parameters in any case. So he included the Cd/I in the excel sheet.

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  @Eng.tarekyoussefАй бұрын

  @ahmedjameel4578 is right. "Cd" is already included. I multiplied the original RSA load case (not reduced by I/R) by Cd/R. You can use the reduced demand of RSA load case (multiplied by I/R) called " Internal force-X or Y" and multiply it by Cd/I, and you will get the same results.

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  @aslshining13 ай бұрын

  hello sir, is equivalent static method and equivalent lateral force analysis are the same? if not, what's the difference?

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  @Eng.tarekyoussef3 ай бұрын

  Yes same

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  @shareqinamdar89033 ай бұрын

  Informative video

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  @Eng.tarekyoussefАй бұрын

  Thanks

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  @shareqinamdar89033 ай бұрын

  Great explanation related to multi story spandrel IDs

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  @Eng.tarekyoussefАй бұрын

  Thank you

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  @shareqinamdar89033 ай бұрын

  Informative but why did you assign only 4 pier labels? Each individual legs should be assigned separate pier label isn't it?

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  @Eng.tarekyoussefАй бұрын

  Detailed Design: If the goal is to perform a detailed design analysis, you can assign separate pier labels for each individual leg of the shear wall. This approach enables a detailed evaluation of the forces and moments acting on each individual segment of the wall, allowing for a precise design that meets the specific structural demands of each part. Overall Resistance: In cases where the primary interest is understanding the overall resistance of the core wall, assigning fewer pier labels (such as one for each major section or core) can be sufficient. This approach simplifies the analysis and focuses on the global performance of the wall.

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  @shareqinamdar89033 ай бұрын

  Can you share the CAD file?

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  @Eng.tarekyoussefАй бұрын

  Please review the layout in the video. It is easy to copy

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  @shareqinamdar89033 ай бұрын

  Nice explanation

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  @Eng.tarekyoussefАй бұрын

  Thank you

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  @elenajivkova13083 ай бұрын

  Thanks a lot for everything. Are you thinking of continuing?

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  @Eng.tarekyoussef3 ай бұрын

  Yes, soon

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  @shareqinamdar89033 ай бұрын

  Nice explanation

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  @Eng.tarekyoussef3 ай бұрын

  Thank you

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  @ahmedtalib7173 ай бұрын

  Hi, Tarak .. Did you have the updated Excel file to include the ACSE7-16 in your axel sheet? since the value of the Fa and Fv are changed?

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  @Eng.tarekyoussef3 ай бұрын

  Hello Ahmad. Not yet updated to ASCE 7-16. I am using ASCE 7-10 in my excel sheets.

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  @user-qk1jf5nl7z4 ай бұрын

  Great job

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  @Eng.tarekyoussef4 ай бұрын

  Thank you

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  @user-mm1bd3cw4b4 ай бұрын

  Torsion amplification should late in the same time of p delta effect or not Thank you

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  @Eng.tarekyoussef3 ай бұрын

  In my opinion, examining torsion amplification after incorporating the P-Delta effect in the analytical model is the optimal approach. The P-Delta effect accounts for the geometric nonlinearity caused by the interaction between axial loads and lateral displacements. Once this effect is considered, assessing torsion amplification becomes relevant as it captures how lateral displacements induce additional torsional moments, particularly in asymmetric or eccentrically loaded structures. By addressing the P-Delta effect first, the analytical model can provide a more comprehensive understanding of the structure's behavior under lateral loads, including torsional responses.

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  @ViraMustafa4 ай бұрын

  if our Ax value comes out to be more than 3 (lets say 4) then do we need to change our structural system in order to reduce the Ax value or should we just take it 3 and design accordingly?

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  @Eng.tarekyoussef4 ай бұрын

  When the Ax value exceeds 3, it means the structure is at risk of instability due to torsional forces. To ensure safety, it's crucial to follow code requirements closely. If Ax is too high, structural changes are needed to reduce torsional effects and maintain stability.

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  @ViraMustafa4 ай бұрын

  in ASCE 7-22, they have imposed a limitation of using the second approach for RSA in case the TIR (Delta max/ delta avg) is more than 1.6

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  @Eng.tarekyoussef4 ай бұрын

  The limitation in ASCE 7-22 on using the second approach for RSA when the Torsional Irregularity Ratio (TIR) exceeds 1.6 indicates the importance of considering structural behavior accurately. It's worth noting that the second method, involving physically offsetting the mass, could potentially amplify the effects of accidental torsion for some buildings with torsional first modes. In my opinion, engineers should not adopt any approach blindly. They need to conduct a thorough investigation to determine which approach is more logical and accurately predicts the real response of the structure.

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  @ronykhadra31733 ай бұрын

  @@Eng.tarekyoussef if TIR exceeds 1,6 and a RSA is required, i think that it is ok to compute the Ax from the ELF procedure and then override the eccentricities in the response spectrum; however, this would require defining U1 and U2 as 2 separate load cases to be able to assign eccentricites for each direction, where applicable; Then, in the combinations, we can use 100% of one direction and 30% of the other; this is not very much recommended since it is better to use U1 and U2 in the same load case so the structure will be oscillated in the principal axis; so whatever we do has its limitations

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  @eng.mohanad83704 ай бұрын

  ياليت الشرح بالعربي

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  @Eng.tarekyoussef4 ай бұрын

  يمكنني مساعدتك إذا كان لديك أي سؤال؟

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  @aldiputra92364 ай бұрын

  How to applying the seismic load if our building rotation from global axis etabs sir..thank because seismic way follow global axis actually..

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  @Eng.tarekyoussef4 ай бұрын

  In the seismic load definition, specify the direction of the seismic load. Since the seismic load follows the global axis, you should align the seismic load direction with the global axis of your structure.

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  @aldiputra92365 ай бұрын

  Normally when I was check using modiefier the reincforcement req be small than if you using default stiffener..why that can be happen you think?? Is it dengerous or not if you reduce the reinforcement because modifier stiffner change??

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  @Eng.tarekyoussef5 ай бұрын

  The reduction in reinforcement requirement when using modifiers compared to default stiffness may occur due to the adjustment in the distribution of loads within the structure. When modifiers are applied, the stiffness characteristics of components is changed, resulting in redistribution of loads within the structure. This redistribution can lead to reduced demands on certain elements, resulting in a lower overall reinforcement requirement. In general, higher stiffness means ==> higher demand forces ==> higher reinforcement ratio

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  @calvoh97154 ай бұрын

  @@Eng.tarekyoussef so does this means in earthquake, the beam having 0.35I reduction in stiffness and column 0.7I means the beams is more flexible than column, therefore, the beam fails first before column? For reduced reinforcement due to stiffness modifier, what does it mean to the beam? the beam with less reinforcement is forced into ductility?

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  @Eng.tarekyoussef4 ай бұрын

  In seismic design, when a structure experiences an earthquake, the stiffness modifiers (such as 0.35I for beams and 0.7I for columns) are used to represent the reduction in stiffness of elements due to various factors like cracking, yielding, or inelastic behavior. Yes, if the beam has a stiffness modifier of 0.35I and the column has a stiffness modifier of 0.7I, it implies that the beam is relatively more flexible compared to the column. However, it doesn't necessarily mean that the beam will fail before the column. The behavior of the structure during an earthquake is complex and depends on various factors including the stiffness, strength, and ductility of individual elements, as well as their connections. Reduced reinforcement due to stiffness modifiers means that during an earthquake, the stiffness of the structure is reduced due to cracking or yielding of reinforcement. This can lead to increased deformations and redistribution of forces within the structure. Regarding your question about the beam with less reinforcement being forced into ductility, it's important to clarify that ductility is a property of materials and structural elements to undergo significant deformation before failure. In seismic design, ductility is desirable as it allows structures to dissipate seismic energy through controlled deformations rather than sudden failure. If a beam has less reinforcement, it may indeed be forced into ductility more readily during an earthquake because it has less resistance to the applied forces. However, this doesn't necessarily mean that it will fail in a ductile manner unless the design and detailing of the structure are done to ensure ductile behavior under seismic loading.

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  @pedjamarkovic66763 ай бұрын

  Also, you should consider stiffness modifier on floors, you will obtain more reinforcement in beams!

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  @aldiputra92365 ай бұрын

  Why bending m11=0.25 not 0.1 y’a?

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  @Eng.tarekyoussef4 ай бұрын

  It's important to note that selecting m11 in ETABS involves an assumption about the out-of-plane stiffness of shear walls. While both 0.25 and 0.1 are commonly used values, I personally opt for 0.25, which involves neglecting 75% of the out-of-plane stiffness of shear walls. This decision aligns with recommendations from the ACI 318-14 code, where the inertia of flat plates and flat slabs, primarily resisting gravity loads and thus experiencing out-of-plane bending, is reduced to 0.25 (Table 6.6.3.1.1). Applying the same concept to shear walls, I choose 0.25 for m11. However, it's important to recognize that the choice ultimately depends on project-specific requirements and engineering judgment.

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  @aldiputra92364 ай бұрын

  @@Eng.tarekyoussef thank you

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  @Joserra9845 ай бұрын

  Hello, great video. So if I use a RSA case I dont need to do an aditional lpad combination sustracting the Eh, like when you use lat equiv force?

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  @UnmeshBane5 ай бұрын

  Hi all, you can use this tool to automate this Pier and Spandrel labelling in few clicks, watch this kzread.info/dash/bejne/rJdlptqIlNDOYLQ.html

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  @raghavmoyade78625 ай бұрын

  Thank you..

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  @Eng.tarekyoussef5 ай бұрын

  You're welcome

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  @nikkorianto27005 ай бұрын

  etabs error during concrete design of frame C6 How to solve this?

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  @akshaythakur23956 ай бұрын

  sir, can we get to know what is refernace for 1DL+0.25LL as multiplier for P-Delta

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  @Eng.tarekyoussefАй бұрын

  P-Delta effects are generally evaluated under service load conditions because these loads reflect the actual conditions the structure will experience during its lifetime. Service loads are the unfactored loads, which include dead loads (DL) and live loads (LL) without any safety factors applied. In structural design, factored loads (which include safety factors) are used for ultimate strength design to ensure safety under worst-case scenarios. However, for evaluating P-Delta effects, which are sensitive to actual displacements and deformations under normal use conditions, service loads are more appropriate. Why 1DL + 0.25LL? The use of 1DL + 0.25LL as a load combination for P-Delta analysis is intended to provide a reasonable estimate of the service load effects on the structure. The factor of 0.25 for live loads accounts for the likelihood that not all live loads will be present simultaneously and fully across the structure. This partial live load factor reflects a more realistic scenario of load application during the service life of the structure. This approach is supported by design standards such as ASCE 7 and AISC 360.

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  @akshaythakur2395Ай бұрын

  sir, thanks for your reply!!!

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  @DesignNexus246 ай бұрын

  Thanks for this usefull tutorial

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  @Eng.tarekyoussef4 ай бұрын

  You're welcome. Glad it was helpful