impact resistant behaviour of rc slab strengthened with frp sheet

ORIGINAL ARTICLE

Impact resistant behaviour of RC slab strengthenedwith FRP sheet

Abdul Qadir Bhatti Norimitsu Kishi

Kiang Hwee Tan

Received: 19 May 2010 / Accepted: 26 April 2011 / Published online: 10 May 2011

RILEM 2011

Abstract To investigate the impact resistance of RC

slabs strengthened with Fibre Reinforced Plastic (FRP)

sheet to the back of the slab, falling-weight impact tests

were conducted. Two loading types were applied:

iterative loading and single loading. The impact load

was applied to the centre of the RC slab with a free

falling 300 kg steel striker with a diameter of 60 mm.

A total of 12 RC slabs that were 1,650 (L) 9 1,650

(W) 9 150 (h) mm were used for these experiments. In

this study, the strengthening method and material

properties of the FRP sheet and the number of FRP

sheet layers were varied. The results obtained from this

study are as follows: (1) the impact resistance of the RC

slabs can be improved by attaching a strengthened FRP

sheet to the back surfaces; (2) the load bearing

mechanism of RC slabs depends on the loading type

and strengthening volume of the FRP sheet; and (3) the

dynamic amplification factor is about two, which is

independent of the load bearing mechanism of the RC

slab and the strengthening volume and tensile rigidity

of the FRP sheet.

Keywords FRP sheet RC slab Impact resistantbehaviour Lower cover concrete spalling

1 Introduction

Increasing attention has focused on applying

advanced composite materials, especially Fibre Rein-

forced Plastic (FRP) laminates and strips, in the field

of structural engineering. Extensive applications of

FRP composites as construction materials have been

accomplished recently [13]. FRP composites are

lightweight, high-strength, non-corrosive and non-

magnetic materials. There is a wide range of recent,

current and potential applications of these materials

that cover both new and existing structures. Recently,

to upgrade the load-carrying capacity of existing

Reinforced Concrete (RC) structures, many strength-

ening and retrofitting works have been conducted in

Japan [46]. In these strengthening works, not only

the steel plate jacketing method and/or the concrete

covering method but also the Fibre Reinforced Plastic

(FRP) sheets bonding method have been applied. The

FRP sheet bonding method is an excellent method for

strengthening existing RC structures because FRP

A. Q. Bhatti (&)Department of Earthquake Engineering, School of Civil

and Environmental Engineering, National University

of Sciences & Technology, NUST, Islamabad, Pakistan

e-mail: [email protected]; [email protected]

N. Kishi

Civil Engineering, Muroran Institute of Technology,

Muroran 050-8585, Japan

K. H. Tan

Department of Civil Engineering, National University

of Singapore, 1 Engineering Drive 2,

Singapore 117576, Singapore

Materials and Structures (2011) 44:18551864

DOI 10.1617/s11527-011-9742-9

sheets have the following advantages: (1) high tensile

strength, (2) easy manoeuvrability because it is a

lightweight and limp material; and (3) high durability

for robustness against environmental influences.

Currently, uni-directional FRP sheets are typically

produced. Therefore, to strengthen plate members

such as RC slabs or an RC wall, FRP sheet must be

orthogonally bonded one after the other to improve

the application process of FRP sheet to strengthen RC

slab structures [79]. Moreover, current studies that

have focused on the FRP sheet bonding method under

static load-carrying capacity of RC slabs have been

conducted by many researchers [5, 1012]. However,

research on upgrading the impact resistance capacity

has not been carried out yet.

Thus, in this study, to investigate the impact

resistant behaviour of RC slabs with FRP sheet

bonded to the back surface, falling-weight impact

tests were conducted considering loading type,

strengthening method, material properties and vol-

ume of the FRP sheet as variables [1315]. FRP

sheets used in these experiments are uni/cross-

directional Aramid FRP (AFRP) sheets and Carbon

FRP (CFRP) sheets; in addition, the cross-directional

AFRP sheet is newly developed and can resist

orthogonally acting forces with one sheet [1618].

2 Experimental Overview

2.1 Specimen

Table 1 shows the list of RC slabs used in this study as

well as the strengthening method, loading type and

impact velocity of a falling weight for each specimen.

The material properties of FRP sheets are listed in

Table 2. The nominal names of these RC slabs are

designated based on the strengthening material (N:

non-strengthening; A: strengthening with AFRP; C:

strengthening with CFRP), the weaving method of the

FRP sheet (1: uni-directional weaving, 2: cross-direc-

tional weaving), the number of FRP sheet layers, the

loading type (II: iterative loading, IS: single loading),

and the impact velocity (m/s) for the single loading test.

Notations for the strengthening material and weaving

method were combined. Then, the specimens of A1/

C1-2, A2-1 possess almost the same tensile stiffness in

orthogonal directions. However, the area of the FRP

sheet for slab A2-2 is about two times larger than that of

the other strengthened slabs.

Figure 1 shows the dimensions and rebar arrange-

ment of the RC slab and the strengthening area of the

FRP sheet. The dimensions for all RC slabs used here

were 1,650 9 1,650 9 150 mm. D13 (13 mm)

deformed bars (SD295A) were used and arranged at

intervals of 150 mm in orthogonal directions.

Regarding boundary conditions on the four sides;

the opposite two sides of the RC slab were pinched

on the top and bottom surfaces at a point 125 mm

inside from the edges to prevent the slab from spring

up. The main shaft supporting the RC slab was free to

rotate (pinned condition) [1922]. The other opposite

sides were free to move and to rotate. Photo 1 shows

the experimental setup for the impact loading tests.

At the beginning of the experiments, the average

compressive strength and elastic modulus of concrete

were 16.7 MPa and 13.9 GPa, respectively. The yield

strength of rebar was 354.5 MPa [2326].

Table 1 List of RC slabsSpecimen Strengthening method Loading

type

Impact velocity

V (m/s)

N-II Non-strengthening Iterative 1, 2, 3, 4

N-IS4 Single 4

N-IS5 5

A1-2-II One uni-directional AFRP sheet bonded

orthogonally

Iterative 1, 2, 3, 4, 4.5, 5

C1-2-II One uni-directional CFRP sheet bonded

orthogonally

Iterative 1, 2, 3, 4, 4.5, 5

A2-1-II One cross-directional AFRP sheet bonded Iterative 1, 2, 3, 4, 4.5, 5

A2-1-IS5 Single 5

A2-1-IS6 6

A2-2-II Two cross-directional AFRP sheet bonded Iterative 1, 2, 3, 4, 4.5, 5, 5.5

1856 Materials and Structures (2011) 44:18551864

2.2 Strengthening process

In this experiment, to improve the bonding capacity

of the FRP sheet, shot blasting and primer coating

treatment were applied to the bonding surface of each

RC slab before bonding to the FRP sheet. When

bonding uni-directional FRP sheets orthogonally

(A1-2, C1-2), FRP sheets for the first layer were

bonded in the main-rebar direction; those for the

second layer were bonded in the orthogonal direction.

When bonding the cross-directional AFRP sheet

(A2-1), the sheets that were 1 m in width were bonded

in the main-rebar direction. Moreover, for A2-2, the

FRP sheets for the second layer were bonded in the

orthogonal direction. For all strengthened RC slabs, no

anchoring treatment was applied at the edge of the

FRP sheets.

2.3 Impact loading test

The impact load was applied by a free falling 300 kg

steel striker with a diameter of 60 mm onto the centre

of the RC slabs. Two loading types for subjecting

impact load were applied: iterative and single loading.

The iterative loading tests were conducted for all kinds

of RC slabs with (1) 1 m/s initial impact velocity that

was incremented by 1 m/s up to V = 4 m/s, and then

(2) 0.5 m/s increments in impact velocity until the RC

slab collapsed. In this experiment, it is assumed that the

RC slabs have collapsed when the cumulated residual

displacement reached 28 mm, which is 1/50th of the

clear span length. In addition, single loading tests with

V = 4, 5 m/s and V = 5, 6 m/s impact velocities were

conducted for slabs N-IS and A2-1-IS, respectively,

Table 2 Material properties of FRP sheets

FRP sheet Mass per unit

area (g/m2)

Thickness

t (mm)Tensile strength

(GPa)

Youngs Modulus

E (GPa)Tensile stiffness

per unit width

E t (kN/mm)

Uni-directional AFRP sheet 415 0.286 2.48 126.5 36.2

Uni-directional CFRP sheet 300 0.167 4.07 230.5 38.5

Cross-directional AFRP sheet 435/435 0.3/0.3 2.48 126.5 38.0/38.0

Fig. 1 Dimensions of an RC slab

Photo 1 Experimental setup

Materials and Structures (2011) 44:18551864 1857

in which the former impact velocities are the same as

the final impact velocity for each RC slab in the

iterative loading test and in which the latter ones are the

same with an impact velocity 1 m/s greater than the

final velocity [12, 2729].

In these experiments, the time histories of weight

impact and reaction forces and displacement at the

loading point of the RC slab (hereinafter, displace-

ment) were continuously recorded using a wide

band data recorder. After experiments, to observe

the crack patterns due to punching shear, the RC

slabs were cut along the centreline in the main-rebar

direction.

3 Experimental results

3.1 Characteristics of the responses

Figure 2 compares the time histories of impact and

reaction force P, R and displacement d for each RCslabs. Figure 2a and b are for results of the iterative

and single loading test, respectively. Here, the reac-

tion force is evaluated by summing up the output from

both supporting points. From Fig. 2a, it is seen that

impact forces P for all slabs suddenly increase at the

beginning because of the weight of the impact. The

maximum amplitude for each slab increases as the

impact velocity increases until V = 3 m/s. After that,

for V = 4 m/s, the maximum amplitude at the begin-

ning is smaller than that at V = 3 m/s, and the second

predominant sinusoidal half wave is excited, which

has a low amplitude and a duration of about 20 ms.

Furthermore, when the impact velocity exceeds

4.5 m/s, the incident wave at the beginning disap-

pears, and a sinusoidal half wave with a low amplitude

and duration of 30 ms is generated [3032].

The wave configuration of the action force R is

similar among all specimens. The maximum ampli-

tude of the reaction force for each slabs increases as

the impact velocity increases until V = 3 m/s. For

V = 4 m/s, the amplitude is lower than that of

V = 3 m/s. In cases over V = 4.5 m/s, the wave is

composed of two sinusoidal waves: one wave with a

duration of 30 ms and the other wave with a period of

about 15 ms.

Observing time histories of displacement d, it isevident that the amplitude for each RC slab increases

as the impact velocity increases, and the residual

displacement is almost zero until V = 3 m/s. For

V = 4 m/s, the maximum amplitude increases sud-

denly. In particular, for slab N-II, the residual

displacement is as large as the maximum one, and

the RC slab must collapse due to punching shear

failure. When the impact velocity exceeds 4.5 m/s,

the wave configuration of the displacement for

strengthened RC slabs is similar among the tested

scenarios [3335].

From these results, it can be seen that RC slabs behave

elastically until V = 3 m/s because residual displace-

ment is almost restored for each RC slab. However,

when the impact velocity is greater than 4 m/s, RC slabs

behave elasto-plastically because residual displacement

occurs for all slabs. The elastic limit for all RC slabs may

be an impact velocity of V = 3 m/s.

From Fig. 2b, it is seen that the wave configura-

tions of slab N for single loading tests (N-IS) at

V = 4 and 5 m/s are similar to those for iterative

loading tests (N-II) at V = 3 and 4 m/s, respectively.

The slabs A2-1-IS at V = 5 and 6 m/s are similar to

that for the iterative loading test (A2-1-II) at

V = 4 m/s. Thus, slabs N-IS and A2-1-IS can sustain

impact loading until V = 4 m/s and 5 m/s, respec-

tively. From these results, it is seen that the impact

velocity of RC slab reaches its final state when single

loading is larger than that under iterative loading.

3.2 Hysteretic loop of reaction force (R)

displacement (d)

The hysteretic loops of reaction force (R)displace-

ment (d) are compared for each slab in Fig. 3. Here,Fig. 3a and b show the results for the iterative and

single loading tests, respectively. From Fig. 3a, it is

seen that the hysteretic loops are similar among all

specimens considered here until V = 3 m/s, except for

slab N-II at V = 2 and 3 m/s. Therefore, the reaction

force increases as displacement increases, and then

after reaching maximum value, it decreases as it passes

through the loading path. Thus, these RC slabs are in

the elastic region until the impact velocity reaches

V = 3 m/s impact velocity. The configurations of the

hysteretic loop for V = 4 m/s are triangular, which

implies that at this impact velocity, a punching shear

cone may develop in the RC slabs, and the shear cone

may be pulled out a little. When the impact velocity

exceeds V = 4 m/s, the maximum reaction force is less


than that at V = 4 m/s because the punching shear

cone has already been developed.

From Fig. 3b, it is observed that slab N-IS still

behaves almost elastically at V = 4 m/s. However, at

V = 5 m/s, the RC slab reaches its final state of

punching shear failure mode because the hysteretic

loop is triangular. However, it is recognised that slab

A2-1-IS at V = 5 and 6 m/s behaves similarly to that

at V = 4 m/s of iterative impact loading. Moreover,

the maximum reaction force at V = 6 m/s is less than

that at V = 5 m/s. Thus, it can be seen that slab

A2-1-IS at V = 6 m/s has already been in its final state.

Fig. 2 Time histories of impact force P, reaction force R and displacement d


3.3 Distributions of maximum impact forces,

reaction forces and residual displacement

Figure 4 shows the distributions of maximum

response values: (a) maximum impact force Pud;

(b) maximum reaction force Rud; and (c) cumulated

residual displacement dcr, taking the impact velocityas abscissas. From Fig. 4a, it is seen that the impact

forces Pud for slabs A2-1/2-II at V = 3 m/s are

similar to those at V = 4 m/s, and these are maxi-

mum among all cases considered here for the iterative

impact loading test. However, the impact forces Pudfor the other slabs have a maximum value at

V = 3 m/s. When the impact velocity exceeds

V = 4.5 m/s, the impact forces Pud for all slabs

decrease significantly to about 80 kN. For the single

loading test, the impact forces Pud for each slab are

larger than those for the iterative loading test.

From Fig. 4b, it is seen that for the iterative

loading test, the reaction force Rud of N-II is the

smallest among those for all slabs at each impact

velocity. The reaction forces Rud for slabs A1/C1-2-II

reach their maximum values at V = 3 m/s, but at

V = 4 m/s, the reaction forces decrease to the same

level as that for slab N-II in the iterative loading test.

However, the reaction forces Rud for slabs A2-1/2-II

at V = 4 m/s are greater than those for slabs A1/C1-

2-II. From these results, it is seen that the strength-

ening effects of cross-directional AFRP sheet on

dynamic load carrying capacity are greater than those

of the uni- directional FRP sheet, which implies that

bonding a cross-directional AFRP sheet can disperse

Fig. 3 Comparisons of hysteretic loops for reaction forcedisplacement


tensile stress more effectively across the back surface

of the RC slab than orthogonal bonding of a uni-

directional FRP sheet. For the single loading test, it is

seen that the reaction forces Rud for all slabs are

greater than the cases of iterative loading tests, which

is similar to the results mentioned above for the

impact force Pud.

Observing Fig. 4c, for the iterative impact loading

test, it is recognised that cumulated residual displace-

ments dcr for all slabs increase linearly as the impactvelocity increases to V = 3 m/s. When the impact

velocity exceeds V = 4 m/s, these increase exponen-

tially as the impact velocity increases. Comparing the

residual displacement dcr for all RC slabs atV = 4 m/s, that for slab N-II is the largest and those

for slabs A2-1/2-II are the smallest.

For the single loading test, because the residual

displacement dcr for slab N-IS at V = 4 m/s is verysmall (about 5 mm), the slab may behave almost

elastically. The value for slab N-IS at V = 5 m/s was

not measured precisely because of spalling of the

lower cover concrete. The residual displacement dcrfor slab A2-1-IS increases as the impact velocity

increases. However, the residual displacement dcr atV = 5 m/s is small and is half that of the iterative

loading test. From these results, it can be seen that the

impact response behaviour of the RC slab is strongly

affected by the loading history.

3.4 Punching shear behaviour

Photo 2 shows an example of the failure conditions on

the bottom surface of RC slabs. Here, the experimental

results for slabs N/A2-1-IS5 tested by single loading

type of V = 5 m/s are shown. From these photos, for

slab N-IS5, it is recognised that the punching shear

cone is completely spalled, and cracks due to bending

and/or torsion are generated. However, for slab A2-1-

IS5, which is strengthened with a cross-directional

AFRP sheet, it is seen that a punching shear cone is

formed, and the AFRP sheet around that (see hatched

area) is peeled off. However, the AFRP sheet has never

been ruptured, and the sheet outside the peeled area has

been completely bonded yet. From these results,

spalling of the punching shear cone can be prevented

by strengthening with an FRP sheet. Moreover, from

the results of other strengthened RC slabs, it has been

recognised that the failure condition on the bottom

surface of each slab is almost the same, independent of

the FRP sheet material, strengthening method, and

loading type.

Photo 3 shows the crack patterns in the cross section

along the centreline for all RC slabs considered here.

From these photos, it is observed that for the iterative

loading test, the punching shear cone for slab N-II is

formed at a slope of about 45 degrees. However, the

punching shear cone for the strengthened RC slabs

forms a gradual slope from the middle surface. The

punching shear cone for slab A2-2-II forms in the

lowest area of the cross section of the RC slab among

all slabs considered here, which implies that as the

tensile rigidity of the strengthening FRP sheet

increases, the shear cone flattens. One of the aspects

observed in the experimental results is the develop-

ment of a bidirectional action. Although the slabs are

simply supported, the ratio between the diameter of the

impactor and the associated dynamically loaded

localised area and the dimensions of the slab may

yield a bi-directional type of behaviour. The cracking

pattern observed in Fig. 2 also indicates such

Fig. 4 Distributions of maximum impact and reaction forces Pud and Rud, respectively, and cumulative residual displacement dcr


behaviour. This phenomenon may explain the advan-

tageous behaviour of the bi-directional FRP system.

An AFRP sheet can disperse tensile stress occurring in

the back surface of the RC slab more effectively than a

uni-directional FRP sheet.

Observing the crack patterns in RC slabs for the

single loading test, it is seen that as the impact

velocity increases, the damage becomes more severe.

The damage for slabs N-IS-4 and A2-1-IS-5 for the

single impact loading test are not as severe as those

for the iterative loading test at the same velocity.

3.5 Static and dynamic load carrying capacity

Tables 3 and 4 show the details of the static punching

shear capacity authorised by authors (hereinafter, static

capacity) and the maximum reaction force obtained

from this study (hereinafter, dynamic capacity) for the

Photo 2 An example failure condition in the bottom surface of RC slabs

Photo 3 Crack pattern in the cross section of RC slab


iterative and single loading tests, respectively. In these

tables, the dynamic capacity ratio and static capacity

ratio are calculated by normalizing with reference to

the dynamic and static capacities of non-strengthened

slab N, respectively. The dynamic amplification factor

is obtained by dividing the dynamic capacity by the

static capacity. Here, the shape of the loading gigue

used in the static loading test was the same as that used

in the impact loading test.

From these tables, it is seen that the dynamic capacity

ratios of strengthened RC slabs are distributed from 1.2

to 1.3, independent of the loading type, strengthening

method, material properties, and volume of FRP sheet.

However, the static capacity ratio of slabs A1-2, C1-2

and A2-1 and slab A2-2 are about 1.3 and 1.5,

respectively. From these results, it is seen that the static

capacity ratios tend to be larger than those with dynamic

capacity. Dynamic amplification factors for all slabs are

about two, independent of the loading type, strengthen-

ing method, material properties and volume of FRP

sheet.

4 Conclusions

In this study, to investigate the impact resistance

behaviour of RC slabs when a FRP sheet is bonded to

the back surface, falling-weight impact tests were

conducted considering loading type, strengthening

method, material properties and volume of FRP sheet

as variables. The results obtained from this study are

summarised as follows:

(1) The elastic limit for all RC slabs considered

here is an impact velocity of V = 3 m/s.

(2) The impact resistance of RC slabs can be

upgraded by bonding a strengthened FRP sheet

to the back surface.

(3) The crack pattern observed from the experiment

clearly shows the development of bi-directional

yielding of slabs. Therefore, it may explain the

advantage of the FRP system in a bi-directional

FRP system. The AFRP strengthening effects of

a bi-directional AFRP sheet are greater than

those of a uni-directional FRP sheet because the

bi-directional AFRP sheet can disperse tensile

stress occurring in the back surface of the RC

slab more effectively than a uni-directional FRP

sheet.

(4) The impact response behaviour of an RC slab is

strongly affected by the loading history.

(5) The dynamic amplification factors for all slabs

are about two, irrespective of the loading type,

strengthening method, material properties and

volume of FRP sheet.

References

1. Kishi N, Zhang G, Mikami H (2005) Numerical cracking

and debonding analysis of RC beams reinforced with FRP

sheet. J Compos Constr ASCE 9(6):507514

2. Kishi N, Ohno T, Konno H, Bhatti AQ (2006) Dynamic

response analysis for a large scale RC girder under a falling

weight impact loading. In: International conference on

Table 3 Experimentalresults of dynamic load

carrying capacity for the

iterative loading test

Specimen Static

capacity

(kN) (1)

Static

capacity

ratio

Dynamic

capacity

(kN) (2)

Dynamic

capacity

ratio

Dynamic

amplification

capacity (2)/(1)

N-II 142 1.00 321 1.00 2.27

A1-2-II 186 1.32 421 1.31 2.26

C1-2-II 183 1.30 382 1.19 2.08

A2-1-II 188 1.33 399 1.24 2.12

A2-2-II 206 1.46 427 1.33 2.07

Table 4 Experimental results of the dynamic load carrying capacity for the single loading test

Specimen Static capacity

(kN) (1)

Static capacity

ratio

Dynamic capacity

(kN) (2)

Dynamic capacity

ratio

Dynamic amplification

capacity (2)/(1)

N-IS-4 142 1.00 283 1.00 2.00

A2-1-IS-5 188 1.33 367 1.30 1.95


advances in engineering structures, mechanics & con-

struction, University of Waterloo, Ontario, Canada, May

1417, pp 99109

3. Kishi N, Bhatti AQ (2010) An equivalent fracture energy

concept for nonlinear dynamic response analysis of pro-

totype RC girders subjected to falling-weight impact

loading. Int J Impact Eng 37:103113

4. Japan Concrete Institute, Prospective technique of concrete

(2002) Volume 03

5. Kishi N, Mikami H, Matsuoka KG, Kurihashi Y (2001)

Failure behavior of flexural strengthened RC beams with

AFRP sheet. In: Proceedings of FRPRCS-5, pp 8795

6. Kishi N (2004) Practical methods for impact tests and

analysis. Struct Eng Ser JSCE 2004:15

7. Benmokrane B, Zhang BR, Chennouf A (2000) Tensile

properties and pull-out behavior of AFRP and CFRP rods

for grouted anchor applications. Constr Build Mater

14(3):157170. doi:10.1016/S0950-0618(00)00017-9

8. Benmokrane B, Zhang BR, Chennouf A, Masmoudi R (2000)

Evaluation of aramid and carbon fibre reinforced polymer

composite tendons for prestressed ground anchors. Can J Civ

Eng 27(5):10311045. doi:10.1139/cjce-27-5-1031

9. Buyukozturk O, Hearing B (1998) Failure behavior of

precracked concrete beams retrofitted with FRP. J Compos

Constr 138144

10. Chennouf A, Benmokrane B (1997) Tensile properties and

pull-out behavior of fiber reinforced plastic ground

anchors. Proc Annu Conf Can Soc Civ Eng 6:141150

11. Erki MA, Rizkalla SH (1993) Anchorages for FRP rein-

forcement. Concr Int Des Constr 15(6):5459

12. Naaman AE, Namur GG, Alwan JM, Najm HS (1991)

Fiber pull-out and bond slip. I: Analytical study. J Struct

Eng 117(9):27692790. doi:10.1061/(ASCE)0733-9445

(1991)117:9(2769)

13. Agardh L (1999) Validation of Numerical simulations of

structural response via material sample testing and field

trials-comparative studies of concrete elements subjected

to transient loads. In: 3rd Asia pacific conference on shock

& impact loads on structures, 1999, November 2426,

Singapore, pp 113

14. Bamonte P, Coronelli D, Gambarova PG (2003) Smooth

anchored bars in NSC and HPC: a study on size effect.

J Adv Concr Technol 1(1):4253. doi:10.3151/jact.1.42

15. Bangash T, Munjiza A (2002) FEM/DEM modeling of RC

beams under impact. Seventh International Conference on

Structures under impact, SUSI 2002, Montreal, pp 519528

16. Bhatti AQ, Kishi N, Mikami H, Ando T (2009) Elasto-

plastic impact response analysis of shear-failure type RC

beams with shear rebars. J Mater Des 30(3):502510

17. Bhatti AQ, Kishi N (2010) Constitutive model for absorbing

system of RC girders used in Rock-sheds under falling

weight impact loading test. J Nucl Eng Des 240:26262632

18. Bhatti AQ, Kishi N, Mikami H (2011) An applicability of

dynamic response analysis of shear failure type RC beams

with lightweight aggregate concrete under falling-weight

impact loading. J Mater Struct 44(1):221231. doi:

10.1617/s11527-010-9621-9

19. Bhatti AQ, Kishi N, Konno H, Mikami H. Elasto-plastic

dynamic response analysis of prototype RC girder under

falling-weight impact loading considering mesh size effect.

J Struct Infrastruct Eng. doi:10.1080/15732479.2010.492838

20. Budelmann H, Kepp B, Rostasy FS (1990) Fatigue

behavior of bond-anchored unidirectional glass-FRPs. In:

Serviceability and durability of construction materials:

proceedings of the first materials engineering congress,

pp 11421151

21. Chen Y, May IM (2009) Reinforced concrete members

under drop-weight impacts. Proc Inst Civ Eng Struct Build

162(1):4556

22. Ghose A (2009) Strategies for the management of bridges

for vehicular impacts. Proc Inst Civ Eng Struct Build

162(1):310

23. Izatt C, May IM, Lyle J, Chen Y, Algaard W (2009) Per-

foration owing to impacts on reinforced concrete slabs.

Proc Inst Civ Eng Struct Build 162(1):3744

24. Jones J, Fraser R (2009) Ship impact on concrete offshore

platform legs. Proc Inst Civ Eng Struct Build 162(1):2125

25. Nanni A, Bakis CE, Boothby TE (1997) Externaly bonded

FRP composites for repair of RC structures, non-metallic

(FRP) reinforcement for concrete structures. In: Proceed-

ings of the third international symposium, vol 1,

pp 303310

26. Nam JW, Kim HJ, Kim SB, Byun KJ (2009) Analytical

study of finite element models for FRP retrofitted concrete

structure under blast loads. Int J Damage Mech,

18(5):461490

27. May IM, Chen Y (2006) An experimental investigation of

the high-mass low-velocity impact behavior of reinforced

concrete members. In: Proceedings of the 2nd international

conference on design and analysis of protective structures,

Singapore, pp 417430

28. Morrison JK, Shah SP, Jenq YS (1988) Analysis of fiber

debonding and pull-out in composites. J Eng Mech

114(2):277294. doi:10.1061/(ASCE)0733-9399(1988)114:

2(277)

29. Nanni A, Tomas J (1996) Grouted anchors for carbon FRP

tendon. Proc Mater Eng Conf 1:527534

30. Ouyang C, Pacios A, Shah SP (1994) Pull-out of inclined fibers

from cementitious matrix. J Eng Mech 120(12):26412659.

doi:10.1061/(ASCE)0733-9399(1994)120:12(2641)

31. Parker J (2009) Ship impact protection for Hungerford

Bridge, London, UK. Proc Inst Civ Eng Struct Build

162(1):1119

32. Paul DK, Abbas H, Godbole PN, Nayak GC (1993) Air-

craft crash upon a containment structure of a nuclear power

plant. In: Transactions of the 12th international conference

on structural mechanics in reactor technology (SMiRT-12),

1520 August, MPA, University of Stuttgart. Elsevier,

Germany. pp 157162

33. Stang H, Li Z, Shah SP (1990) Pull-out problem: stress

versus fracture mechanical approach. J Eng Mech

116(10):21362150. doi:10.1061/(ASCE)0733-9399(1990)

116:10(2136)

34. Zhang BR, Benmokrane B, Chennouf A, Mukhopadhyaya

P, EI-Safty A (2001) Tensile behavior of FRP tendons for

prestressed grouted anchors. J Compos Constr ASCE

5(2):8593

35. Wu Z, Yang S, Zheng J, Hu XZ (2010) Analytical solution

for the pull-out response of FRP rods embedded in steel tubes

filled with cement grout. Mater Struct 43(5):597609. doi:

10.1617/s11527-009-9515-x


Impact resistant behaviour of RC slab strengthened with FRP sheetAbstractIntroductionExperimental OverviewSpecimenStrengthening processImpact loading test

Experimental resultsCharacteristics of the responsesHysteretic loop of reaction force (R)--displacement ( delta )Distributions of maximum impact forces, reaction forces and residual displacementPunching shear behaviourStatic and dynamic load carrying capacity

ConclusionsReferences

impact resistant behaviour of rc slab strengthened with frp sheet

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