Asset Publisher Asset Publisher

Masonry Structures (a.y. 2019/20)

Programme

The goal of the course is to provide an introduction to materials, construction practices, structural behaviour, analytical methods, and typical code requirements for the design of new masonry buildings and the evaluation and retrofit/rehabilitation of existing ones, with special regard to seismic action. Properties of masonry materials: brick, block, mortar, grout and reinforcement. Mechanics of masonry in compression: failure theories, compressive strength, elastic modulus. Behaviour of masonry walls subjected to lateral forces and their role in building structural systems excited by earthquake motions. Unreinforced masonry walls: vertical and transverse loadings, failure mechanisms, capacity models. Building systems: analysis under vertical and under horizontal loading; role of floor diaphragms. Liner vs. nonlinear analysis. Reinforced masonry walls: behaviour, design, detailing of reinforcement. Confined masonry. Assessment and rehabilitation of existing masonry buildings: sources of vulnerability, knowledge and survey of the structure, methods of analysis, performance criteria. Strategies for seismic rehabilitation/retrofitting.

Prerequisites:  undergraduate course in reinforced concrete structures, fundamentals of structural dynamics and earthquake engineering


TOPICS OF THE COURSE

  • Introduction to masonry construction methods. Structural, non-structural, unreinforced, reinforced, stone, brick, block, partitions, parapets, infills, veneer. General structural layout and conception of a masonry buildings
  • Properties of masonry materials, compressive strength, modulus of elasticity, modulus of rupture, etc.
  • Mechanics of masonry in compression.
  • URM walls in compression (load bearing walls), effects of slenderness.
  • URM walls in bending (load bearing walls)
  • URM walls in bending and compression (out-of-plane), behaviour under lateral out-of-plane load (wind, seismic).
  • URM walls under in-plane lateral loads. Failure mechanisms/limit states. Strength formulae. Force-displacement behaviour. Bi-linear idealization.
  • Structural analysis of URM buildings. Idealizations under prevailing vertical loads, idealizations under horizontal loads. Rigid diaphragm systems, flexible diaphragm systems
  • Seismic response of URM building systems. Global analysis governed by in-plane response. Elastic analysis. Nonlinear analysis
  • Local out-of-plane seismic assessment/safety check of URM walls.
  • Lateral strength and behaviour of reinforced masonry (RM) walls. Flexural strength, shear strength, stiffness, detailing of reinforcement
  • Seismic response of RM buildings. Design and seismic performance assessment.
  • Confined masonry.
  • Behaviour of non-structural masonry components.
  • Review of modern codes approaches to seismic design and methods of analysis (linear static, nonlinear static, linear dynamic, nonlinear dynamic).
  • Assessment of seismic performance of existing buildings. Overview. Experience from past earthquakes and from experiments. Sources of vulnerability. Response mechanisms (reprise).
  • Performance-based criteria for seismic assessment with reference to recent codes (discussion of ASCE-SEI 41)
  • Assessment of seismic performance of existing buildings. The EC8 - Italian approach. Survey and knowledge levels, methods for assessment. Local mechanisms. Application of limit analysis. 
  • Strengthening/retrofitting strategies and techniques.

Execution

Week

Date

Lecture hours

From___To___

Tutorial hours

From__ To___

Tot h

Topic

1

07/01/2020

14.15 – 17.30

 

3

Intro to masonry construction methods. Structural, non structural, unreinforced, reinforced, stone, brick, block, partitions, parapets, infills, veneer.  General structural layout and conception of a masonry buildings. Homework #0.

08/01/2020

09.15 – 12.30

 

3

Properties of masonry materials, compressive strength, modulus of elasticity, modulus of rupture, etc. Mechanics of masonry in compression. Homework assignment #1

09/01/2020

09.15 – 12.30

 

3

URM walls in compression (load bearing walls), effects of slenderness.

 

14.15 – 16.15

 

2

URM walls in bending (load bearing walls) Homework assignment #2

Lecturer: M. Griffith

10/01/2020

09.15 – 12.00

 

2.5

URM walls in bending and compression (out-of-plane), 2nd order geometric effects in urm walls (compression, compression and lateral loading). Homework assignment #3

 

 

12.00 – 13.00

14.00 – 15.00

2

Contact hours – lab

2

13/01/2020

09.15 – 12.30

 

3

URM walls under in-plane lateral loads. Failure mechanisms/limit states. Strength formulae. Force-displacement behaviour. Bi-linear idealization Homework #4

 

14.15 – 17.30

 

3

Structural analysis of URM buildings. Idealizations under prevailing vertical loads, idealizations under horizontal loads. Rigid diaphragm systems, flexible diaphragm systems.

14/01/2020

 

16.00 – 18.00

2

Contact hours – lab

15/01/2020

09.15 – 12.30

 

3

Seismic response of URM building systems. Global analysis governed by in-plane response. Elastic analysis. Nonlinear analysis.

 

 

14.00 – 16.00

2

Lab session and homework assignment #5

16/01/2020

09.15 – 11.30

 

2

Local out-of-plane seismic assessment/safety check of URM walls.

17/01/2020

09.00 – 13.00

 

3

Lateral strength and behaviour of reinforced masonry walls. Flexural strength, shear strength, stiffness, detailing of reinforcement.

3

20/01/2020

14.15 – 17.30

 

3

Presentation and discussion of papers.

21/02/2020

09.15 – 12.30

 

3

Seismic response of RM buildings. Design and seismic performance assessment. Homework assignment #6. Confined masonry.

 

 

14.00 – 16.00

2

Contact hours – Lab workshop

22/01/2020

09.15 – 12.30

 

3

Behaviour of nonstructural masonry components 2 h + Seismic assessment of existing buildings.

 

 

14.00 – 16.00

2

Lesson + Contact hours discussion of previous homeworks.

23/01/2020

 

11.00 – 13.00

2

Lab session on nonlinear software + contact

24/01/2020

 

09.15 – 12.30

3

Homework #7. Survey, condition assessment and knowledge base for existing masonry buildings.

4

27/01/2020

14.15 – 18.00

 

3.5

Strengthening/retrofitting strategies and techniques part 1.

28/01/2020

09.15 – 12.30

 

3

Strengthening/retrofitting strategies and techniques part 2.

29/01/2020

09.00 – 11.00

 

2

Seminar on experimental investigation on retrofit strategies for urm masonry buildings.

 

 

11.00 – 12.30

1.5

Contact hours – Lab workshop

31/01/2019

09:30-13:00

Final Exam

 

 

Bibliography

  • Handouts and scientific papers made available during the course
  • T.Paulay and M.J.N.Priestley, Seismic design and assessment of reinforced concrete and masonry buildings, Chapter 7, John Wiley and Sons, 1997
  • R. Drysdale and A. Hamid, Masonry Structures: Behavior and Design, 3rd ed., The Masonry Society, 2008.
  • M. Tomaževič, Earthquake resistant design of masonry buildings,  Imperial College Press, London, 1999. 
  • A.W. Hendry, Structural Masonry, 2nd ed., Palgrave Macmillan,  1998.

Exam

Grading:
Problem Assignments:  40%
Final Exam   60%
 

Guido Magenes

Professore Ordinario di Tecnica delle costruzioni (art. 6, comma 11 L. 240/2010)

Cycle :  XXXIII, XXXIV, XXXV

Course type : Specialist

Curriculum : Earthquake Engineering and Engineering Seismology

Period: Semester I

Academic year: 2019-2020