Monthly Presentation Laboratory of Engineering for ...€¦ · Monthly Presentation Laboratory of...

Monthly PresentationLaboratory of Engineering for Maintenance System

B4 Matsuo Yoshinori

Contents

1. My research theme

2. Strengthening Method

3. Debonding modes

4. Debonding strength models

5. Future plan

1. My research theme

My research theme is …

Key Words

FRP(Fiber Reinforced Plastics)

Bond

Debonding

Damage of Existing part of beams

Environmental influence

2. Strengthening Methods

Strengthen

Repair

To make something stronger, or to

become stronger

To make something that is broken or

damaged satisfactory again

2. Strengthening Methods

There are some methods of strength.

To bond FRP or Steel plate to structures.

There are three method of bonding.

This method relate to my research theme.

① Overlay method

② Bonding method

③ Inducing of pre-stress method

④Extension of elements methodetc…..

2. Strengthening Methods

1. Steel sheet bonding method

2. FRP sheet bonding method

3. Continuous fiber sheet bonding method

R

3. Debonding modes

Failure modes of ERP-strengthened RC beams

(a)FRP rupture

(b)Crushing of compressive concrete

(c)Shear failure

RC beams failure before debonding.

3. Debonding modes

Failure modes of ERP-strengthened RC beams

(d) Concrete cover separation

(e) Plate end interfacial debonding

(f) Intermediate crack induced interfacial debonding

3. Debonding modes

Then mode (d), (e), and (f) can be classified

into two categories.

Thus, there are many research about debonding.

(A) Plate end debonding (B) Intermediate crack induced

interfacial debonding

4. Debonding strength models

There are 12 models of debonding

strength. 7 of 12 models are for FRP

sheets and 5 of 12 models are for steel.

These models are classified into three

categories.

[Back ground]

4. Debonding strength models

3 debonding strength models

(a) Shear capacity based models

(b) Concrete tooth models

(c) Interfacial stress based models

4. Debonding strength models

(a) Shear capacity based models

This model focuses “shear crack”.

Shear crack and debonding occur same time … (assumption)

4. Debonding strength models

(b) Concrete tooth models

Concrete tooth

To define “tooth” as left figure

and debonding deemed to

occur when the “tooth” failure.

4. Debonding strength models

(c) Interfacial stress based models

4. Debonding strength models

In this model, thinking about minim element of the beam at the plate end,

and then we calculate shear and longitudinal stress.

Mohr-Coulomb failure criterion

Right figure shows minim element

of the beam at the plate end.

5. Future plan

8 9 10 11 12

Studying entrance

examination

Pre-study,

Reading paper

To prepare

experiment

experiment

I must research about my experiment…

Thank you for your kind attention!