© 2

01

1 B

en

tley S

yst

em

s, In

corp

ora

ted

Rakesh Pathak, Ph.D.,Rakesh Pathak, Ph.D.,Software Research EngineerSoftware Research Engineer

SOURCES OF NONLINEAR SOURCES OF NONLINEAR DEFORMATIONS IN LIGHT FRAME WOOD DEFORMATIONS IN LIGHT FRAME WOOD SHEAR WALLSSHEAR WALLS

© 2

011

Bent

ley

Syst

ems,

Inco

rpor

ated

2 | WWW.BENTLEY.COM

Physical DescriptionSimplified Deflection FormulaAnalytical ModelRevisiting basics of Virtual WorkParametric StudySummary and Conclusions

PRESENTATION OUTLINE

© 2

011

Bent

ley

Syst

ems,

Inco

rpor

ated

3 | WWW.BENTLEY.COM

SHEAR WALL: DESCRIPTION

© 2

011

Bent

ley

Syst

ems,

Inco

rpor

ated

4 | WWW.BENTLEY.COM

SHEAR WALL: DEFLECTION FORMULA

© 2

011

Bent

ley

Syst

ems,

Inco

rpor

ated

5 | WWW.BENTLEY.COM

FINITE ELEMENT MODELING

© 2

011

Bent

ley

Syst

ems,

Inco

rpor

ated

6 | WWW.BENTLEY.COM

FINITE ELEMENT MODELING: NAIL PROPERTY

© 2

011

Bent

ley

Syst

ems,

Inco

rpor

ated

7 | WWW.BENTLEY.COM

• Virtual work is defined as the “work done by either virtual forces acting through real displacement or by real forces acting through virtual displacement”

VIRTUAL WORK: LINEAR APPLICATION

© 2

011

Bent

ley

Syst

ems,

Inco

rpor

ated

8 | WWW.BENTLEY.COM

VIRTUAL WORK: NONLINEAR APPLICATION

© 2

011

Bent

ley

Syst

ems,

Inco

rpor

ated

9 | WWW.BENTLEY.COM

• 8 ft x 8 ft

• Nail Type

• Nail Spacing

• Panels

• Frames

• 36 combinations

PARAMETRIC STUDY: DESCRIPTION

© 2

011

Bent

ley

Syst

ems,

Inco

rpor

ated

10 | WWW.BENTLEY.COM

PARAMETRIC STUDY: NONLINEAR VIRTUAL WORK VERIFICATION

© 2

011

Bent

ley

Syst

ems,

Inco

rpor

ated

11 | WWW.BENTLEY.COM

PARAMETRIC STUDY: FRAME CONTRIBUTION

© 2

011

Bent

ley

Syst

ems,

Inco

rpor

ated

12 | WWW.BENTLEY.COM

PARAMETRIC STUDY: PANEL CONTRIBUTION

© 2

011

Bent

ley

Syst

ems,

Inco

rpor

ated

13 | WWW.BENTLEY.COM

PARAMETRIC STUDY: NAIL CONTRIBUTION

© 2

011

Bent

ley

Syst

ems,

Inco

rpor

ated

14 | WWW.BENTLEY.COM

PARAMETRIC STUDY: TOTAL DEFLECTION

© 2

011

Bent

ley

Syst

ems,

Inco

rpor

ated

15 | WWW.BENTLEY.COM

• This paper presents nonlinear virtual work application study for the first time.

• Displacement contribution from framing elements is found to be nonlinear and not linear as specified in IBC.

• Displacement contribution from panels elements matches well with IBC.

• Displacement contribution from nails between finite element model and IBC. are found to be very different.

• Nails in finite element models were observed to carry more load compared to IBC specified Table.

SUMMARY AND CONCLUSIONS

© 2

011

Bent

ley

Syst

ems,

Inco

rpor

ated

16 | WWW.BENTLEY.COM

• IBC inelastic drift is found to be conservative for all the models when compared with Finite Element results.

• The parametric study shows some differences between IBC and finite element results

• Wood Diaphragm flexibility calculation may get affected in certain scenarios but further study is needed as similar differences there may offset the error in flexibility calculations.

SUMMARY AND CONCLUSIONS