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Earthquake Engineering Structural Engineering Turkey

Session 56: Lessons learned from sequential EQs in Turkey

INTRODUCTION

LIVE TECHNICAL DISCUSSION SERIES


◼ Sequential of EQs were happened. Magnitude 7.8 happened at 4 am, and Magnitude 7.5 happened at 1 pm (many 6.5 in between). Record from one station indicates that PGA of the first mainshock was around ~0.7g. The spectral acceleration exceeded 2g around 0.5-0.6 seconds. Additionally, the vertical acceleration was ~1.4g.

◼ Over 10,000 buildings were collapsed by the EQs. And many of the buildings were built before 2000. So, they were designed based on old Turkish Code. Collapses were mostly multi-story/mid-rise (5-20 stories). They were mainly concrete buildings.

◼ Collapses should be evaluated in two categories; are collapses before the second mainshock and collapses after the second mainshock (plus aftershocks).

◼ Collapses before the second mainshock: Collapsed buildings were designed based on reduced EQ loads (using response modification factor (R)) by relying on ductility; however, the collapses showed nonductile behavior (brittle). Please, check both ductile and brittle collapse on the graph below. Basic ductile design philosophy is “survive the main shock, and get out of the building safely”. However, the collapses indicate that design reinforcements were didn’t supplied as required by the code. Designers – authority of jurisdictions – constructors should be one mechanism to follow the code instructions.

◼ Collapses after the second mainshock: Many of the collapses were obtained after the second main shock (Magnitude 7.5). The first main shock and aftershocks softened/weakened/hinged buildings, and the second mainshock destroyed most of the softened buildings. This is because of P-delta (large deformation). Why? Because it causes negative tangent stiffness on the buildings, and when it exceeds the plastic stiffness (hinged stiffness), buildings are collapsed due to instability. And the other consideration is fracture due to low cycle fatigue. Ductile elements have a finite accumulative strain capacity.

◼ Important lessons: One of the important lessons is missing sequential shocks specification on every seismic code in the world. It might be great research to study performance-based design for sequential shocks! Other one is determining/reviewing/retrofitting old buildings. Old buildings should get engineering services based on new code provisions.

In the upcoming live event, Dr. T. Deniz Uludag will join us for the very important discussion.

Please note that the discussion will be based on initial analysis/thoughts. We may organise more numbers of sessions in the future as and when more detailed analysis is shared by the investigation teams.

It would be great if you can share your specific queries/doubts related to Turkey EQs in advance which would help us to structure the flow of discussion.

In the following registration form, you may share the specific doubts/questions related to the topic or you may share your point of view, discussion points, etc. which may be addressed during the session.

Schedule

Title: Lessons Learned from Sequential Earthquakes in Turkey

DATE : 28-FEB-23

TIME : 9:30PM to 11:00PM IST | 9:00AM to 10:30AM MST

Brief about Expert

Dr. T. Deniz Uludag- Structural Engineer, PhD, EIT at Martin/Martin, Inc.

Dr. T. Deniz Uludag is a PhD in earthquake engineering who was born, raised, educated in Turkey.  He has performed a lot of research on Turkey EQs and has connections to the field.

He completed his Ph.D. under the supervision of Dr. Jay Puckett in Architectural Engineering (Structural) at the University of Nebraska-Lincoln (UNL). His specialization is in structural dynamics, performance-based design, and collapse prediction related to providing resilience for operational recovery after high-seismic events.

He is working as an Engineer-In-Training (EIT) in the Structural Department in the Lakewood, Colorado office of Martin/Martin, Inc .

During his academic career at UNL, Dr. Patrick McManus, is a principal in Structural Engineering at Martin/Martin Consulting Engineers, is/was his co-advisor and helped him to develop a novel structural system for seismic loads. This system is practical and directly applicable to professional practice in high-seismic areas. With Dr. McManus’s mentorship and encouragement, he gained an industry perspective paramount for his research and professional development in general. Dr. McManus serves on several AISC technical committees.

HOW TO REGISTER FOR THE EVENT?

Registration is FREE. You may share the specific doubts/queries/discussion points which may be discussed during the session. It would help us to structure the discussion.

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An online course related to design of steel structures as per AISC 360-22 will commence from 15-MAR-23. The course will cover discussion on important clauses of the code AISC 360-22, AISC 341-16, AISC 358-16 as well as application of same in the software STAAD.Pro & RAM connection. The course will cover the important areas such as stability of structures, notional loads, P- delta analysis, direct analysis method, design of compression members with and without slender elements, design of member for bending, design of member for combined forces, design of simple connections, design of moment connections, earthquake resistant design aspects, etc. Click here for more details.

Feedback of few participants for previous online courses”

Prashanth N

The course STEEL-STR-001 was well planned and the sessions were very interactive and informative.

Ajay Narayan Jadhav

The course WIND-STR-001 provided Excellent clarifications on IS875 clauses.

Nitin Sharma

I would like to thanks and appreciate for this helpful course comprising of STAAD PRO Training and Design concepts for RCC and Steel. In this module I have learned in detail about essential concepts for designing industrial buildings and gained an understanding of different types of Analysis. I also acquired the knowledge of different types of Codes. Moreover, l was introduced with FEM, design of foundation, anchor bolts and connections. All the sessions were very interactive and engaging. The valuable knowledge that i have gained in these two months will certainly be propitious to start my career as a structural engineer.

Akshay Thakur

REC-STR-001: The recorded sessions are more than anything for tackling practical difficulties…. and you bring some other professionals like dr. Jain and dr. Gupta is just like awesome experience for the student like me who are from tier-3 college who won’t get such a precious information… thanks to you also for the knowledge you impart… best luck to you and your team for this your initiative to resolve practical difficulties among aspiring structural engineers… 🙏🏻 once again thank you so much… because nobody in today’s era from structural engineering domain is wants to share the information, but you do… kudos!

RATHISH V R

I really enjoyed throughout the journey of the course STEEL-STR-001 wherein I improved by Fundamental Knowledge in the Design of Steel Structures. Bhavin Sir’s explanation on Lateral Torsional Buckling and other critical areas, really helped me to become sound in manual calculations. Keep continuing the good work!

Dipal Trivedi

The course GEO-STR-001 effectively addressed the gap between geotechnical and structural engineer. It not only covers important interface areas but also discusses consequences of poor interface. Subject experts have in depth knowledge and experience to address expectations of various participants ranging from fresh engineering graduate to highly experienced professionals. The course is interactive and experts are more than willing to address any queries of the participant. The course content is appropriately divided into multiple sessions over the weekend to allow flexibility to participants to participate and reflect during the week at their convenience. Overall, this course is highly recommended for structural and geotechnical engineers for gaining and enhancing the understanding of the very important interface between geotechnical and structural engineering work.

Anal Shah

The course WIND-STR-002 was so interactive and Dr. Abhay Gupta was so kind enough to listen to all queries and answer them in very great detail. Also time spent by Dr. Gupta is highly appreciated. Great job Dr. Gupta in spreading the knowledge.

Mainak Ghosal

The Course WIND-STR-002 was very effective. It changed my perspective on not only wind engineering but also seismic loading analysis. Dr.Gupta also referred some excellent books which would not have been possible otherwise. Last but not the least, Dr. Gupta was kind enough to give me the charges of highlighting the errata for the Explanatory Handbook on Wind Engineering.

Kamlesh Mehta

In the course WIND-STR-002, I was not able to attend few lectures due to internet connectivity problem. But I have gone through the video lectures provided by Mr. Bhavin shah and it is positive point that any time any where we can watch and update our knowledge.

M. K. Haridharan

In the course ETABS-STR-001, all the session are very interactive, it has a touch with theory, hands on training and practical aspects. The knowledge of the mentor is extraordinary in all aspects.

Haridharan M K

The online course EQ-STR-001 was very informative and it covered all the aspects of IS1893, IS16700, IS13920 and more important sharing the videos of the course which enabled to go through at any time.

Er. Sachi Parekh

I appreciate the course structure designed by Er. Bhavin Shah , which includes the theory and implementation of coddle provisions to software and interpretation of results. By attending it, I am able to learn and explore the analogy of a software – Staad Pro. Thank you very much for sharing the knowledge and make my doubts crystal clear…

I must say that he is a true professional academician
Like a bridge between Institute and industry…

 

Ajay Narayan Jadhav

WIND-STR-002 : Excellent sessions. Thanks a lot to team SQVe and the eminent speaker for giving a valuable knowledge.

Rajen Dharia

On attending to STEEL-STR-01 course with the multi discipline participates from across India is the best part of this course. As the questions raised and its solutions, are many a times very new for each other during the sessions which enhance our knowledge in different practical applications and approach towards it’s solution. I Recommend to join STEEL-STR-01 to all upcoming Structural Engineers.

Dhirender Singh Bisht

I am pursuing masters in structural engineering and steel was the topic that I found always challenging since my B.Tech times. Moreover this is also a missing topic for the syllabus of many universities in masters program. To understand its theory ,and execute it practically in software is really challenging and need a mentor for that. I’ve been following Bhavin sir from last few months and was it was my good decision to choose him as a guide. By the course STEEL-STR-001, now I can feel that I am in a position to explore boundaries of IS code, and also I’m enthusiastic to see how Euro code, AISC code and other countries code tackles the problem which sounds to be complicated in IS code.

ZEESHAN MUNSHI

After attending online course STAAD-STR-001, I m very happy to share that….now I understand the result which I get after analysis……and how to use or understand the STAAD editor. Thank u so much for that…!!

Supriya Pal

I AM A PHD SCHOLAR AND WORKING IN THE FIELD OF WIND STRUCTURE INTERECTION. I GOT A LOT OF MY DOUBTS CLEARED THROUGH THIS COURSE : WIND-STR-002. THANKYOU VERY MUCH

Harikrishnan

Faculty engineering knowledge is excellent. These course STEEL-STR-001 is useful for fresher and experienced person.

Parth Gandha

The course STAAD-STR-001 was really amazing an knowledgeable. As I fresher I gained so much knowledge about all the little things I didn’t know that were so much important. Troubleshooting of the software was the most important topic as a single wrong interpretation of the warning can totally change the outcome. I heartily thanks Shri Bhavin bhai and SQVE consultants for introducing such wonderful courses so that we can perform good in practice.

Ravichandra

STEEL-STR-001 is very wonderful course. I have learned many things through this course. During session Bhavin sir interaction with the participants is very great with clear explanations. We are expecting these type of courses in future also.

Akash Solanki

STEEL-STR-001 was the best package for understanding the limit state design of steel structures using IS800:2007 along with its application in STAAD.Pro. Tremendous wealth of knowledge from Bhavin sir combined with queries by other participants really facilitated a great learning experience. Thank you for such an amazing course. I hope more such courses are on the way.

JAKEER HUSSAIN

WIND-STR-002 : Explanation regarding wind action and building response due to wind, and the way of clarifications to participants questions by Dr. Abhay Gupta sir was excellent. Looking forward to attend relevant upcoming webinars/courses.

Mr. AJAY NARAYAN JADHAV

JUST TO APPRECIATE THE WORKSHOP STAAD-STR-001, IT HAS BEEN VERY USEFUL FOR ME. I WOULD LIKE TO HIGHLIGHT THE DYNAMIC OF THE SESSIONS, VERY ACTIVE, INTERESTING, AND WELL ORGANISED AND GREAT TO SHARE EXPERIENCES. MANY THANKS TO THE SPEAKER AND ORGANISERS!!…..ONCE AGAIN THANK YOU FOR SHARING AN INSPIRING LEARNING EXPERIENCE 👍

Srinivasa Reddy

Dear Sir thank you so much for your Course ETABS-STR-001. We learn Lot from here. Happy to Join this Course we are waiting for next Upcoming Courses.

Sujata Gupta

It gives a good awareness about software as well as corresponding codal provisions. So one can get technical knowledge as well as how software using clauses giving in codes. Teacher is very patient, soft spoken and knowledgeable person. Topics selected in the course STEEL-STR-001 are very relevant, useful and to the point for design and analysis of steel structure.

Ashish Sawant

The course WIND-STR-001 is very informative. It clears basics of overall concept of wind flow. Thanks to Bhavin sir and Gupta sir for your guidance on wind loading.

Praveen Upadhyay

Bhavin Shah is a fantastic trainer, very friendly and encouraging, it was a well-delivered and presented course (STAAD-STR-001) that was well received by the group. There was a great balance between theory and practice and the concepts were clearly and professionally explained.

Dr. Vinubhai Patel

The course WIND-STR-002 was really very much informative and useful. Enjoyed a lot.

Tanuja Singh

STEEL-STR-001 : Excellent initiative to bring clarity of concepts to professionals.

Dr. Raksha Parolkar

Topics covered in WIND-STR-002 were new for me to understand, as it has never been covered in syllabus. But the way Dr. Abhay Gupta sir taught, explained the problems and shared his experiences, the subject got easy to understand. I feel proud of being his student.

Rajashree

The course WIND-STR-001 facilitated discussion and understanding of concepts  in more detailed simplified manner under the experienced and knowledgeable professionals. Thank you Dr Abhay sir and Bhavin sir.

Shreyas Barad

STEEL-STR-001 is much awaited course. Finally the industry expert teaching the right thing with right methodology. I had never seen such an excellent online course like this. The amount of knowledge and engagement was extremely good. Thank you so much for the wonderful course.

Alok Rathore

After attending the course WIND-STR-001, I change my prospective towards structure and learn many concept.

Hiren Desai

The course WIND-STR-002 is very much informative as well as useful for practicing engineers considering the non availability of easy to detailed literatures and practical examples.

Shefali Thakkar

STEEL-STR-001 was the best interactive course ,wherein all practical facts and limitations those are related with prevailing standards, software and practices were discussed. Vision was provided to participate towards solving such prevailing limitations rather following the same collaboratively. Course content was described very effectively and constant encouragement on experiments of the course deliverables and raising doubts and solving the same. Effective time management by faculty to satisfy all participants’ queries along with effective delivery of course content. 24 hour interaction facility was made available for solving course related queries.

D. Nivetha

The Staad Pro Training sessions were extremely fruitful, informative and it gave deeper insights into the field of structural engineering. Bhavin sir had not only taught us the software of Staad Pro, but he had explained us several technical concepts based on his field experiences. It was an interactive session where sir had asked us questions and it helped us think a lot and come up with solutions. Overall, it’s been a great experience and this 25 day of training has taught me a lot and has inspired me to develop greater passion towards civil engineering.

REVA VENU V M

I am a budding geotechnical engineering professional. For three years I have worked as faculty in NIT and recently joined as project fellow- geotechnical engineering in a research Institute. Now I am in the transition phase of my career ie, shifting from academics to industry. My desire to become a geotechnical engineering consultant inspired me to join this course. As I don’t have much industrial exposure, attending the course GEO-STR-001 helped me to gain a lot of practical knowledge related to geotechnical engineering. Especially the discussions related to soil investigation, interpretation of soil report and interactive sessions were really amazing. Queries of other participants and the discussions associated with it,were really informative, as it mainly focussed on current industrial practices. Thank you Vivek sir and Bhavin sir for giving this wonderful opportunity. Hoping for a better support in my future endeavours too. Also expecting further courses related to this, in the coming future.

BHARATENDU PATEL

This course related to STAAD.Pro and case studies was beyond the conventional software training. It helped me conceptualise the idea behind the behaviour of any structure, understand the special requirements between steel and concrete structures. Real life case study and interactive sessions made the learning more impactful.

Tarnpreet Singh Gill

The course content for STEEL-STR-001 has been thoroughly devised to be effective in best manner. Sharing of Recorded Sessions was the best part as I myself missed few end sessions due to office pressure but I could complete these later on. Making a permanent whatsapp group for discussion was also a good idea.

Praveen Vasishth

STEEL-STR-001 is very useful course for updating to new code for steel design of buildings.

Anvitha Yadama

It has been an excellent course and given me an in-depth understanding on ETABS and STAAD.Pro software . I feel more confident in my understanding and it helped me complete my major project in my B. Tech course .Thank you for all the support and excellent teaching. During the training program all my queries were answered quickly.

Hemanth Ponnuri

STEEL-STR-001 course is very informative and very well explained about the hidden insights in the IS800 code.

Sharad Gupta

I am very grateful to Er. Dr. Abhay Gupta and Mr. Bhavin Shah for sharing your knowledge with us even though we have the same profession. Your course WIND-STR-002 helped me to clear many of the doubts I had sine the past 20 years.

Mohd Ameen Irfan

Bhavin Sir is very experienced and expert in his field, He made the topics in online course STAAD-STR-001 very clear from the scratch and also addressed every student’s queries and problems very nicely!!!

Kunal Patil

At first I never expected the sessions which are going to be conducted would be so knowledgeable. Day by day listening to Abhay sir touching every aspect from the codal point of view, few from his own experience. The mixture of everything made this course WIND-STR-002 very valuable and useful. Before this course I was trying to learn from everywhere how does this wind dynamic forces are to be calculated but through SQVE consultants arranging this webinar and learning under experience fraternity was worthwhile.

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