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Hi,  .. . . Eng. Anas Dawas. I'm glad to try to help you on this.

I understand your question and I had to expand my DATABASE to answer with full experience.
In Brazil we do not have Earthquakes so I had a limited experience in this design.  Because of this, I was thinking if the transfer beam with D-REGIONS and I was associate to STM approaches initially to solve localized structural themes like beam openings and variable depth, and so specific optimizations like that:  

So Let's try to solve this!!

I do some personal research and here some of my thoughts:

*Unsymmetrical forms of building can have low performance than those with symmetric configurations.

I supposed that I am seeing a structural concrete seismic resistant frame "MRF" and assuming you are giving preference to the selection of a "Structural Concrete Frame" to advance with your answer.

Essential items in the ASCE 7-16:

CHAPTER C2 COMBINATIONS OF LOADS

C2.3.6 Basic Combinations with Seismic Load Effects

"The seismic load effect including overstrength factor, Em, is combined with other loads. The purpose for load combinations with overstrength factor is to approximate the maximum seismic load combination for the design of critical elements, including discontinuous systems, transfer beams and columns supporting discontinuous systems, and collectors. The allowable stress increase for load combinations with overstrength is to provide compatibility with past practice".

C12.3 DIAPHRAGM FLEXIBILITY, CONFIGURATION IRREGULARITIES, AND REDUNDANCY

C12.3.2 Irregular and Regular Classification

. . . The configuration of a structure can significantly affect its performance during a strong earthquake that produces the ground motion contemplated in the standard. Structural configuration can be divided into two aspects: horizontal and vertical. Most seismic design provisions were derived for buildings that have regular configurations, but earthquakes have shown repeatedly that buildings that have irregular configurations suffer greater damage. "This situation prevails even with good design and construction."…

C12.3.2.2 Vertical Irregularity

Vertical lateral force-resisting elements at adjoining stories that are offset from each other in the vertical plane of the elements and impose overturning demands on supporting structural elements, such as beams, columns, trusses, walls, or slabs, are classified as in-plane discontinuity irregularities (Type 4).

C12.3.3.3 Elements Supporting Discontinuous Walls or Frames.

. . . The purpose of requiring elements (e.g., beams, columns, trusses, slabs, and walls) that support discontinuous walls or frames to be designed to resist seismic load effects including overstrength is to protect the gravity load-carrying system against possible overloads caused by overstrength of the seismic force-resisting system. Either columns or beams may be subject to such failure; therefore, both should include this design requirement. Beams may be subject to failure caused by overloads in either the downward or upward directions of force. Examples include reinforced concrete beams . . . 

"The connection between the discontinuous element and the supporting member must be adequate to transmit the forces required for the design of the discontinuous element".

*First of all, we might recognize THAT D-REGION IS ALWAYS IMPORTANT WHEN SHEAR FORCES EXISTS!!

*So I performed an additional Structural Analysis as well. . . for this simply imaginary simulation: 

*In my view – It Would be important give concern where the ABRUPT CHANGES in GEOMETRY can cause the UNCONVENTIONAL FLOW on the SHEAR forces. Designing the TRANSFER BEAM and the 2 COLUMNS BELLOW would be interesting to increase RESILIENCE: (TB, C and B)  or +A in the future if you plan to remove column "B" in order to CREATE some additional Aesthetics SPACE between the C- - -A.

I think it was my first time on this topic (SEISMIC), I hope it would be right on the majority of the explanations, if not, things not all the time have to be perfect, sometimes correct me as well if needed.
Thanks, Andre.

. . . and you can find an additional material over this question linking the JOINT SEI, CASE and NCSEA and the STRUCTURE MAGAZINE Initiative, by accessing our colleague:  Emily Guglielmo, P.E., C.E., F.SEI:

STRCTUREMAGAZINE-OVERSTRENGTH

------------------------------
Andre Newinski S.E., A.M.ASCE
Engenheiro Estrutural
AN
Santo Angelo

Original Message:
Sent: 09-28-2022 09:38 AM
From: Anas Dawas
Subject: Over-strength factor

Dear sir ,

I would like to ask about the case shown in the attached picture for a building with intermediate frame system as a LFRS .

Which elements must be designed for over strength factor as per ASCE provisions ?

Hi,  .. . . Eng. Anas Dawas. I'm glad to try to help you on this.

I understand your question and I had to expand my DATABASE to answer with full experience.
In Brazil we do not have Earthquakes so I had a limited experience in this design.  Because of this, I was thinking if the transfer beam with D-REGIONS and I was associate to STM approaches initially to solve localized structural themes like beam openings and variable depth, and so specific optimizations like that:  

So Let's try to solve this!!

I do some personal research and here some of my thoughts:

*Unsymmetrical forms of building can have low performance than those with symmetric configurations.

I supposed that I am seeing a structural concrete seismic resistant frame "MRF" and assuming you are giving preference to the selection of a "Structural Concrete Frame" to advance with your answer.

Essential items in the ASCE 7-16:

CHAPTER C2 COMBINATIONS OF LOADS

C2.3.6 Basic Combinations with Seismic Load Effects

"The seismic load effect including overstrength factor, Em, is combined with other loads. The purpose for load combinations with overstrength factor is to approximate the maximum seismic load combination for the design of critical elements, including discontinuous systems, transfer beams and columns supporting discontinuous systems, and collectors. The allowable stress increase for load combinations with overstrength is to provide compatibility with past practice".

C12.3 DIAPHRAGM FLEXIBILITY, CONFIGURATION IRREGULARITIES, AND REDUNDANCY

C12.3.2 Irregular and Regular Classification

. . . The configuration of a structure can significantly affect its performance during a strong earthquake that produces the ground motion contemplated in the standard. Structural configuration can be divided into two aspects: horizontal and vertical. Most seismic design provisions were derived for buildings that have regular configurations, but earthquakes have shown repeatedly that buildings that have irregular configurations suffer greater damage. "This situation prevails even with good design and construction."…

C12.3.2.2 Vertical Irregularity

Vertical lateral force-resisting elements at adjoining stories that are offset from each other in the vertical plane of the elements and impose overturning demands on supporting structural elements, such as beams, columns, trusses, walls, or slabs, are classified as in-plane discontinuity irregularities (Type 4).

C12.3.3.3 Elements Supporting Discontinuous Walls or Frames.

. . . The purpose of requiring elements (e.g., beams, columns, trusses, slabs, and walls) that support discontinuous walls or frames to be designed to resist seismic load effects including overstrength is to protect the gravity load-carrying system against possible overloads caused by overstrength of the seismic force-resisting system. Either columns or beams may be subject to such failure; therefore, both should include this design requirement. Beams may be subject to failure caused by overloads in either the downward or upward directions of force. Examples include reinforced concrete beams . . . 

"The connection between the discontinuous element and the supporting member must be adequate to transmit the forces required for the design of the discontinuous element".

*First of all, we might recognize THAT D-REGION IS ALWAYS IMPORTANT WHEN SHEAR FORCES EXISTS!!

*So I performed an additional Structural Analysis as well. . . for this simply imaginary simulation: 

*In my view – It Would be important give concern where the ABRUPT CHANGES in GEOMETRY can cause the UNCONVENTIONAL FLOW on the SHEAR forces. Designing the TRANSFER BEAM and the 2 COLUMNS BELLOW would be interesting to increase RESILIENCE: (TB, C and B)  or +A in the future if you plan to remove column "B" in order to CREATE some additional Aesthetics SPACE between the C- - -A.

I think it was my first time on this topic (SEISMIC), I hope it would be right on the majority of the explanations, if not, things not all the time have to be perfect, sometimes correct me as well if needed.
Thanks, Andre.

. . . and you can find an additional material over this question linking the JOINT SEI, CASE and NCSEA and the STRUCTURE MAGAZINE Initiative, by accessing our colleague:  Emily Guglielmo, P.E., C.E., F.SEI:

STRCTUREMAGAZINE-OVERSTRENGTH

------------------------------
Andre Newinski S.E., A.M.ASCE
Engenheiro Estrutural
AN
Santo Angelo

Original Message:
Sent: 09-28-2022 09:38 AM
From: Anas Dawas
Subject: Over-strength factor

Dear sir ,

I would like to ask about the case shown in the attached picture for a building with intermediate frame system as a LFRS .

Which elements must be designed for over strength factor as per ASCE provisions ?

Hi,  .. . . Eng. Anas Dawas. I'm glad to try to help you on this.

I understand your question and I had to expand my DATABASE to answer with full experience.
In Brazil we do not have Earthquakes so I had a limited experience in this design.  Because of this, I was thinking if the transfer beam with D-REGIONS and I was associate to STM approaches initially to solve localized structural themes like beam openings and variable depth, and so specific optimizations like that:  

So Let's try to solve this!!

I do some personal research and here some of my thoughts:

*Unsymmetrical forms of building can have low performance than those with symmetric configurations.

I supposed that I am seeing a structural concrete seismic resistant frame "MRF" and assuming you are giving preference to the selection of a "Structural Concrete Frame" to advance with your answer.

Essential items in the ASCE 7-16:

CHAPTER C2 COMBINATIONS OF LOADS

C2.3.6 Basic Combinations with Seismic Load Effects

"The seismic load effect including overstrength factor, Em, is combined with other loads. The purpose for load combinations with overstrength factor is to approximate the maximum seismic load combination for the design of critical elements, including discontinuous systems, transfer beams and columns supporting discontinuous systems, and collectors. The allowable stress increase for load combinations with overstrength is to provide compatibility with past practice".

C12.3 DIAPHRAGM FLEXIBILITY, CONFIGURATION IRREGULARITIES, AND REDUNDANCY

C12.3.2 Irregular and Regular Classification

. . . The configuration of a structure can significantly affect its performance during a strong earthquake that produces the ground motion contemplated in the standard. Structural configuration can be divided into two aspects: horizontal and vertical. Most seismic design provisions were derived for buildings that have regular configurations, but earthquakes have shown repeatedly that buildings that have irregular configurations suffer greater damage. "This situation prevails even with good design and construction."…

C12.3.2.2 Vertical Irregularity

Vertical lateral force-resisting elements at adjoining stories that are offset from each other in the vertical plane of the elements and impose overturning demands on supporting structural elements, such as beams, columns, trusses, walls, or slabs, are classified as in-plane discontinuity irregularities (Type 4).

C12.3.3.3 Elements Supporting Discontinuous Walls or Frames.

. . . The purpose of requiring elements (e.g., beams, columns, trusses, slabs, and walls) that support discontinuous walls or frames to be designed to resist seismic load effects including overstrength is to protect the gravity load-carrying system against possible overloads caused by overstrength of the seismic force-resisting system. Either columns or beams may be subject to such failure; therefore, both should include this design requirement. Beams may be subject to failure caused by overloads in either the downward or upward directions of force. Examples include reinforced concrete beams . . . 

"The connection between the discontinuous element and the supporting member must be adequate to transmit the forces required for the design of the discontinuous element".

*First of all, we might recognize THAT D-REGION IS ALWAYS IMPORTANT WHEN SHEAR FORCES EXISTS!!

*So I performed an additional Structural Analysis as well. . . for this simply imaginary simulation: 

*In my view – It Would be important give concern where the ABRUPT CHANGES in GEOMETRY can cause the UNCONVENTIONAL FLOW on the SHEAR forces. Designing the TRANSFER BEAM and the 2 COLUMNS BELLOW would be interesting to increase RESILIENCE: (TB, C and B)  or +A in the future if you plan to remove column "B" in order to CREATE some additional Aesthetics SPACE between the C- - -A.

I think it was my first time on this topic (SEISMIC), I hope it would be right on the majority of the explanations, if not, things not all the time have to be perfect, sometimes correct me as well if needed.
Thanks, Andre.

. . . and you can find an additional material over this question linking the JOINT SEI, CASE and NCSEA and the STRUCTURE MAGAZINE Initiative, by accessing our colleague:  Emily Guglielmo, P.E., C.E., F.SEI:

STRCTUREMAGAZINE-OVERSTRENGTH

------------------------------
Andre Newinski S.E., A.M.ASCE
Engenheiro Estrutural
AN
Santo Angelo

Original Message:
Sent: 09-28-2022 09:38 AM
From: Anas Dawas
Subject: Over-strength factor

Dear sir ,

I would like to ask about the case shown in the attached picture for a building with intermediate frame system as a LFRS .

Which elements must be designed for over strength factor as per ASCE provisions ?

Hi,  .. . . Eng. Anas Dawas. I'm glad to try to help you on this.

I understand your question and I had to expand my DATABASE to answer with full experience.
In Brazil we do not have Earthquakes so I had a limited experience in this design.  Because of this, I was thinking if the transfer beam with D-REGIONS and I was associate to STM approaches initially to solve localized structural themes like beam openings and variable depth, and so specific optimizations like that:  

So Let's try to solve this!!

I do some personal research and here some of my thoughts:

*Unsymmetrical forms of building can have low performance than those with symmetric configurations.

I supposed that I am seeing a structural concrete seismic resistant frame "MRF" and assuming you are giving preference to the selection of a "Structural Concrete Frame" to advance with your answer.

Essential items in the ASCE 7-16:

CHAPTER C2 COMBINATIONS OF LOADS

C2.3.6 Basic Combinations with Seismic Load Effects

"The seismic load effect including overstrength factor, Em, is combined with other loads. The purpose for load combinations with overstrength factor is to approximate the maximum seismic load combination for the design of critical elements, including discontinuous systems, transfer beams and columns supporting discontinuous systems, and collectors. The allowable stress increase for load combinations with overstrength is to provide compatibility with past practice".

C12.3 DIAPHRAGM FLEXIBILITY, CONFIGURATION IRREGULARITIES, AND REDUNDANCY

C12.3.2 Irregular and Regular Classification

. . . The configuration of a structure can significantly affect its performance during a strong earthquake that produces the ground motion contemplated in the standard. Structural configuration can be divided into two aspects: horizontal and vertical. Most seismic design provisions were derived for buildings that have regular configurations, but earthquakes have shown repeatedly that buildings that have irregular configurations suffer greater damage. "This situation prevails even with good design and construction."…

C12.3.2.2 Vertical Irregularity

Vertical lateral force-resisting elements at adjoining stories that are offset from each other in the vertical plane of the elements and impose overturning demands on supporting structural elements, such as beams, columns, trusses, walls, or slabs, are classified as in-plane discontinuity irregularities (Type 4).

C12.3.3.3 Elements Supporting Discontinuous Walls or Frames.

. . . The purpose of requiring elements (e.g., beams, columns, trusses, slabs, and walls) that support discontinuous walls or frames to be designed to resist seismic load effects including overstrength is to protect the gravity load-carrying system against possible overloads caused by overstrength of the seismic force-resisting system. Either columns or beams may be subject to such failure; therefore, both should include this design requirement. Beams may be subject to failure caused by overloads in either the downward or upward directions of force. Examples include reinforced concrete beams . . . 

"The connection between the discontinuous element and the supporting member must be adequate to transmit the forces required for the design of the discontinuous element".

*First of all, we might recognize THAT D-REGION IS ALWAYS IMPORTANT WHEN SHEAR FORCES EXISTS!!

*So I performed an additional Structural Analysis as well. . . for this simply imaginary simulation: 

*In my view – It Would be important give concern where the ABRUPT CHANGES in GEOMETRY can cause the UNCONVENTIONAL FLOW on the SHEAR forces. Designing the TRANSFER BEAM and the 2 COLUMNS BELLOW would be interesting to increase RESILIENCE: (TB, C and B)  or +A in the future if you plan to remove column "B" in order to CREATE some additional Aesthetics SPACE between the C- - -A.

I think it was my first time on this topic (SEISMIC), I hope it would be right on the majority of the explanations, if not, things not all the time have to be perfect, sometimes correct me as well if needed.
Thanks, Andre.

. . . and you can find an additional material over this question linking the JOINT SEI, CASE and NCSEA and the STRUCTURE MAGAZINE Initiative, by accessing our colleague:  Emily Guglielmo, P.E., C.E., F.SEI:

STRCTUREMAGAZINE-OVERSTRENGTH

------------------------------
Andre Newinski S.E., A.M.ASCE
Engenheiro Estrutural
AN
Santo Angelo

Original Message:
Sent: 09-28-2022 09:38 AM
From: Anas Dawas
Subject: Over-strength factor

Dear sir ,

I would like to ask about the case shown in the attached picture for a building with intermediate frame system as a LFRS .

Which elements must be designed for over strength factor as per ASCE provisions ?

Hi,  .. . . Eng. Anas Dawas. I'm glad to try to help you on this.

I understand your question and I had to expand my DATABASE to answer with full experience.
In Brazil we do not have Earthquakes so I had a limited experience in this design.  Because of this, I was thinking if the transfer beam with D-REGIONS and I was associate to STM approaches initially to solve localized structural themes like beam openings and variable depth, and so specific optimizations like that:  

So Let's try to solve this!!

I do some personal research and here some of my thoughts:

*Unsymmetrical forms of building can have low performance than those with symmetric configurations.

I supposed that I am seeing a structural concrete seismic resistant frame "MRF" and assuming you are giving preference to the selection of a "Structural Concrete Frame" to advance with your answer.

Essential items in the ASCE 7-16:

CHAPTER C2 COMBINATIONS OF LOADS

C2.3.6 Basic Combinations with Seismic Load Effects

"The seismic load effect including overstrength factor, Em, is combined with other loads. The purpose for load combinations with overstrength factor is to approximate the maximum seismic load combination for the design of critical elements, including discontinuous systems, transfer beams and columns supporting discontinuous systems, and collectors. The allowable stress increase for load combinations with overstrength is to provide compatibility with past practice".

C12.3 DIAPHRAGM FLEXIBILITY, CONFIGURATION IRREGULARITIES, AND REDUNDANCY

C12.3.2 Irregular and Regular Classification

. . . The configuration of a structure can significantly affect its performance during a strong earthquake that produces the ground motion contemplated in the standard. Structural configuration can be divided into two aspects: horizontal and vertical. Most seismic design provisions were derived for buildings that have regular configurations, but earthquakes have shown repeatedly that buildings that have irregular configurations suffer greater damage. "This situation prevails even with good design and construction."…

C12.3.2.2 Vertical Irregularity

Vertical lateral force-resisting elements at adjoining stories that are offset from each other in the vertical plane of the elements and impose overturning demands on supporting structural elements, such as beams, columns, trusses, walls, or slabs, are classified as in-plane discontinuity irregularities (Type 4).

C12.3.3.3 Elements Supporting Discontinuous Walls or Frames.

. . . The purpose of requiring elements (e.g., beams, columns, trusses, slabs, and walls) that support discontinuous walls or frames to be designed to resist seismic load effects including overstrength is to protect the gravity load-carrying system against possible overloads caused by overstrength of the seismic force-resisting system. Either columns or beams may be subject to such failure; therefore, both should include this design requirement. Beams may be subject to failure caused by overloads in either the downward or upward directions of force. Examples include reinforced concrete beams . . . 

"The connection between the discontinuous element and the supporting member must be adequate to transmit the forces required for the design of the discontinuous element".

*First of all, we might recognize THAT D-REGION IS ALWAYS IMPORTANT WHEN SHEAR FORCES EXISTS!!

*So I performed an additional Structural Analysis as well. . . for this simply imaginary simulation: 

*In my view – It Would be important give concern where the ABRUPT CHANGES in GEOMETRY can cause the UNCONVENTIONAL FLOW on the SHEAR forces. Designing the TRANSFER BEAM and the 2 COLUMNS BELLOW would be interesting to increase RESILIENCE: (TB, C and B)  or +A in the future if you plan to remove column "B" in order to CREATE some additional Aesthetics SPACE between the C- - -A.

I think it was my first time on this topic (SEISMIC), I hope it would be right on the majority of the explanations, if not, things not all the time have to be perfect, sometimes correct me as well if needed.
Thanks, Andre.

. . . and you can find an additional material over this question linking the JOINT SEI, CASE and NCSEA and the STRUCTURE MAGAZINE Initiative, by accessing our colleague:  Emily Guglielmo, P.E., C.E., F.SEI:

STRCTUREMAGAZINE-OVERSTRENGTH

------------------------------
Andre Newinski S.E., A.M.ASCE
Engenheiro Estrutural
AN
Santo Angelo

Original Message:
Sent: 09-28-2022 09:38 AM
From: Anas Dawas
Subject: Over-strength factor

Dear sir ,

I would like to ask about the case shown in the attached picture for a building with intermediate frame system as a LFRS .

Which elements must be designed for over strength factor as per ASCE provisions ?

Hi,  .. . . Eng. Anas Dawas. I'm glad to try to help you on this.

I understand your question and I had to expand my DATABASE to answer with full experience.
In Brazil we do not have Earthquakes so I had a limited experience in this design.  Because of this, I was thinking if the transfer beam with D-REGIONS and I was associate to STM approaches initially to solve localized structural themes like beam openings and variable depth, and so specific optimizations like that:  

So Let's try to solve this!!

I do some personal research and here some of my thoughts:

*Unsymmetrical forms of building can have low performance than those with symmetric configurations.

I supposed that I am seeing a structural concrete seismic resistant frame "MRF" and assuming you are giving preference to the selection of a "Structural Concrete Frame" to advance with your answer.

Essential items in the ASCE 7-16:

CHAPTER C2 COMBINATIONS OF LOADS

C2.3.6 Basic Combinations with Seismic Load Effects

"The seismic load effect including overstrength factor, Em, is combined with other loads. The purpose for load combinations with overstrength factor is to approximate the maximum seismic load combination for the design of critical elements, including discontinuous systems, transfer beams and columns supporting discontinuous systems, and collectors. The allowable stress increase for load combinations with overstrength is to provide compatibility with past practice".

C12.3 DIAPHRAGM FLEXIBILITY, CONFIGURATION IRREGULARITIES, AND REDUNDANCY

C12.3.2 Irregular and Regular Classification

. . . The configuration of a structure can significantly affect its performance during a strong earthquake that produces the ground motion contemplated in the standard. Structural configuration can be divided into two aspects: horizontal and vertical. Most seismic design provisions were derived for buildings that have regular configurations, but earthquakes have shown repeatedly that buildings that have irregular configurations suffer greater damage. "This situation prevails even with good design and construction."…

C12.3.2.2 Vertical Irregularity

Vertical lateral force-resisting elements at adjoining stories that are offset from each other in the vertical plane of the elements and impose overturning demands on supporting structural elements, such as beams, columns, trusses, walls, or slabs, are classified as in-plane discontinuity irregularities (Type 4).

C12.3.3.3 Elements Supporting Discontinuous Walls or Frames.

. . . The purpose of requiring elements (e.g., beams, columns, trusses, slabs, and walls) that support discontinuous walls or frames to be designed to resist seismic load effects including overstrength is to protect the gravity load-carrying system against possible overloads caused by overstrength of the seismic force-resisting system. Either columns or beams may be subject to such failure; therefore, both should include this design requirement. Beams may be subject to failure caused by overloads in either the downward or upward directions of force. Examples include reinforced concrete beams . . . 

"The connection between the discontinuous element and the supporting member must be adequate to transmit the forces required for the design of the discontinuous element".

*First of all, we might recognize THAT D-REGION IS ALWAYS IMPORTANT WHEN SHEAR FORCES EXISTS!!

*So I performed an additional Structural Analysis as well. . . for this simply imaginary simulation: 

*In my view – It Would be important give concern where the ABRUPT CHANGES in GEOMETRY can cause the UNCONVENTIONAL FLOW on the SHEAR forces. Designing the TRANSFER BEAM and the 2 COLUMNS BELLOW would be interesting to increase RESILIENCE: (TB, C and B)  or +A in the future if you plan to remove column "B" in order to CREATE some additional Aesthetics SPACE between the C- - -A.

I think it was my first time on this topic (SEISMIC), I hope it would be right on the majority of the explanations, if not, things not all the time have to be perfect, sometimes correct me as well if needed.
Thanks, Andre.

. . . and you can find an additional material over this question linking the JOINT SEI, CASE and NCSEA and the STRUCTURE MAGAZINE Initiative, by accessing our colleague:  Emily Guglielmo, P.E., C.E., F.SEI:

STRCTUREMAGAZINE-OVERSTRENGTH

------------------------------
Andre Newinski S.E., A.M.ASCE
Engenheiro Estrutural
AN
Santo Angelo

Original Message:
Sent: 09-28-2022 09:38 AM
From: Anas Dawas
Subject: Over-strength factor

Dear sir ,

I would like to ask about the case shown in the attached picture for a building with intermediate frame system as a LFRS .

Which elements must be designed for over strength factor as per ASCE provisions ?