Click to edit Master title style. Naveed Anwar, PhD

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1 Click to edit Master title style Naveed Anwar, PhD

2 The Challenges Architectural Design and Structural Engineering Bigger, taller, complex forms, but Lighter, smaller, thinner structural elements High performance, but Lower cost Architects and Structural Engineers Apparent lack of innovativeness Difficulties in collaborative working Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 2

3 Click to edit Master title style Developing a Structural Solution The Conceptualizing Phase

4 Advise to my fellow Engineers 1. Design is a team effort, and Architect is the lead 2. Everything is possible, don t say no! but it needs innovation, knowledge, skills, tools and, of course resources Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015)

5 Conceptualizing a Solution Design a Rectangular Water Tank of 3mx4mx2m Most engineers will readily calculate the wall thickness and required rebars and the cost Design the most efficient and cost effective water tank to hold 24 cum of water Many designs are possible Most engineers will not know how to start? Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 5

6 Decisions Support Systems Explicit learning from experience Combination of Rational and Heuristic thinking Encapsulating natural thinking process into formal decision systems Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015)

7 System Design Rich Pictures Analytical Hierarchy Process (AHP) Artificial Neural Networks (ANN) Genetic Algorithms (GA) Expert Systems (ES) Fuzzy Logic Deep Thinking Big Data and Data Mining Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015)

8 Rich Picture for Choosing Structural System Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 8

9 ANN for Tall Buildings Architectural Layout Preliminary Sizing Structural Response Number of story Length, Width, Height Grid spacing.. Column size Shear wall size Rebar quantities Natural period Drift ratio Base shear To make design preliminary decisions without explicit calculations Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 9

10 Click to edit Master title style IS MY STRUCTURE SAFE? : CBD, PBD, RBD, CBE

11 Is my structure safe? Traditional approach Not sure, but I know I followed the code (ACI/BS..) New approach First, define Safe Safe against what, how safe Second, use explicit evaluation of safety Get freedom from the code Use advanced technologies Get clear answer about safety and performance Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 11

12 Design Approaches Code Based Design (CBD) Performance Based Design (PBD) Risk Based Design (RBD) Consequence Based Engineering (CBE) Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 12

13 Structural Response Can be Linked to Other Decisions Loading Severity Hazard Resta urant Resta urant Consequences Resta urant Vulnerability Structural Displacement Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 13

14 Structural Response Can be Linked to Other Decisions Restaurant Restaurant Restaurant Operational (O) Immediate Occupancy (IO) Life Safety (LS) Collapse Prevention (CP) 0 % Damage or Loss 99 % Ref: FEMA 451 B Lowest Lowest Lowest Casualties Downtime for Rehab Rehab Cost to Restore after event Highest Highest Highest Highest Retrofit Cost to Minimize Consequences Lowest Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 14

15 How to work with PBD Client Architect Performance Based Design Structural Engineer PBD Specialist Site Specific Consultant PBD Reviewer Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 15

16 Cost and Performance C P General Belief Easy to do! CC P Cost Effective Design Can be done C P High Performance Design Can be done C P Highly Innovative Design Hard to do! Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 16

17 Alternate Approach To solve the problem, solve the cause of the problem Performance is a Demand and Capacity balance Traditional way: Increase capacity to meet demand Alternate way: Reduce demand to match capacity Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 17

18 AIT and PBD Just in last 5 years, AIT has become a Regional leader in Performance Based Design of Tall Buildings 55 million Sft Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 18

19 Click to edit Master title style CONTROLLING FORCES AND MOVEMENTS IN STRUCTURES: BRB, dampers, isolators, hinges, fuses

20 Forces Separate the forces into Directly applied, externally applied Movement based Movement based forces can be controlled Mass based Temperature based Settlement based Internal deformation based Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015)

21 Movements Determining Movements Modal Analysis Static Analysis Time History Analysis Wind Tunnel tests Controlling Movements Stiffness and mass distribution Installing Dampers Mechanical, Mass Tuned, Liquid, Viscous Base Isolators Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 21

22 Natural Vibration Natural vibration is the key to controlling most movement based forces Natural Period and Mode Shapes are the pulse of the structure Understanding modal response is vital for engineers and architects Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 22

23 Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 23

24 Buddha Statue, Bangkok Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 24

25 Mechanical Isolators and Dampers Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015)

26 Tuned Dampers Tuned Mass Dampers Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015)

27 BRB Braces that Don t Buckle Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 27

28 Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 28

29 Click to edit Master title style PREVENTING THE DOMINO EFFECT: Progressive collapse analysis

30 Progressive Collapse A new and major concern for structural safety Structure should not collapse completely if one or two elements are destroyed Backup systems, alternate load paths, additional redundancy Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015)

31 Click to edit Master title style ROME WAS NOT BUILT IN A DAY: The construction Sequence analysis

32 Analysing for Construction Sequence Structure is normally analysed as if it is already fully built Make the model, and apply loads Step-wise construction sequence analysis is essential for better and correct understating and design Make the model, as it is built Apply loads as they are applied Consider temporary shoring etc Consider in-construction corrections Consider the aging effects Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015)

33 Without and With Construction Sequence Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 33

34 Click to edit Master title style TOGETHER OR SEPARATE: Free, flexible, or rigid connections

35 Connections Connecting two buildings or parts of structure in the right way can lead to innovative solutions Rigidly connected Fully free to move Flexible connections Elasto-Plastic Connections Fuses Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015)

36 Click to edit Master title style NEWER AND BETTER TOOLS AND TOYS: Advanced modeling and analysis Software

37 Software Modelling capability Object based modelling BIM links between CAD and FEA and building lifecycle Analysis Capability From simple linear-elastic analysis To highly complex nonlinear-inelastic-dynamic analysis Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015)

38 Tools of the Trade for Structural Engineers By Computers and Structures Inc. USA A company created and run by Ashraf Habibullah Integrated 3D Bridge Design Software Integrated Software for Structural Analysis and Design Integrated Analysis, Design and Drafting of Building Systems Integrated Design of Flat Slabs, Foundation Mats and Spread Footings Nonlinear Analysis and Performance Assessment for 3D Structures Design of Simple and Complex Reinforced Concrete Columns Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 38

39 Detailed Seismic Analysis Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 39

40 Click to edit Master title style Some Interesting Solutions

41 Gramercy Residence, Manila Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 41

42 Park Terraces, Manila Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 42

43 Pruksa Precast, Bangkok Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 43

44 Aqua Towers, Manila Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 44

45 Iconic Bridge, Manila Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 45

46 Robbie House, Manila Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 46

47 Precast Houses Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 47

48 Temple Dome, Bangkok Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 48

49 Temple Dome, Bangkok Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 49

50 Fixing the Old to Serve Again Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 50

51 MOFAT, Brunei Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 51

52 Ireo, India Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 52

53 Shanta Glass, Dhaka Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 53

54 Lang Suan, Bangkok Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 54

55 Central Embassy, Bangkok Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 55

56 Central Embassy, Bangkok Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 56

57 Floor 1 to 9 Floor 16 to 30 Floor 9 to 16 Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 57

58 Two e Com, Manila Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 58

59 Star View, Bangkok Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015) 59

60 We like challenges! Thank you Innovative Structural Engineering Naveed Anwar, AIT (IAPEX, Lahore March 2015)

61 Click to edit Master title style