Research ArticleTransmission of Impact Vibration onConcrete and Mortar Sheets
Carlos Moroacuten1 Alfonso Garciacutea1 Daniel Ferraacutendez1 and Viacutector Blanco2
1Departamento Tecnologıa de la Edificacion Universidad Politecnica de Madrid 28040 Madrid Spain2Colegio Santısima Trinidad Alcorcon 28925 Madrid Spain
Correspondence should be addressed to Alfonso Garcıa alfonsogarciagupmes
Received 29 March 2015 Revised 25 May 2015 Accepted 3 June 2015
Academic Editor Longjun Dong
Copyright copy 2015 Carlos Moron et al This is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited
The present work exposes an alternative system for detecting vibrations generated by impact on concrete andmortar sheets In orderto carry out the tests it is necessary to implement a system of measurement different than the one proposed by the current UNE EN140-7 This system consists of an amplifier and a striking device that is also able to measure the deformation of the material oncethe impact has been produced This system is able to detect variations in transmission of vibration at the same frequency betweenthe various building materials employed after establishing a relationship between the theoretical predictions and the experimentalresultsThus this system could be used as a vibration detection system and as an alternative method of standardization of materialsagainst their acoustic characteristics
1 Introduction
Currently there are many tests to better understand theimportance of the vibration transmission in materials andits applications in the building field The current legislationat national level is contained in the Technical BuildingCode (CTE DB-HR) [1] and in the present Instruction forStructural Concrete (EHE-08) [2] and at international levelthrough ISO standards where the importance of acousticallycharacterizing materials against their impact noise reductionis stated as improvement of quality and comfort of the roomsbuilt
Some studies focus on the vibrations caused by peoplewhen they perform dynamic actions on the building floorarea [3] These vibrations may significantly affect the servicebehavior but rarely the fatigue behavior and the safety of thestructure Beyond the noise produced these actions generatefrequencies that can be detected and measured by means ofthe necessary instrumentation and differ depending on theuse that has the built-up area that is to be measured Anothersource of vibrations which also becomes very importantin building is the facilities that generate annoying noisesand is detectable by transmission through the structure even
several meters away from the emitting center The isolationof these vibrations and the study of materials that allow agreater acoustic absorption have already been studied byother researchers and it is still improving today
Among the works that include the use of vibrationto determine certain physical parameters of the materialsthere are different tests dependent on the material and themeasurable characteristics Some authors produced smallmechanical disturbances in the test tubes and the reportedresults correlated with the help of appropriate software withother standardized techniques such as using ultrasound orconventional bending tests subsequently making the anal-ysis of harmonics given by the Fast Fourier Transform todetermine the dynamic Youngmodulus of the material [4 5]At other times the work is done with materials reinforcedwith some type of fibers or additives and a research iscarried out on the improvement obtained due to the additionof that material both structurally and acoustically thesetests generally measure the relationship between flexuraltoughness and impact-induced energy [6] Also in the caseof concrete and mortar a comparison was made betweenthe different fundamental resonant frequencies of the mate-rials transversely vibrated without any restriction [7 8]
Hindawi Publishing CorporationShock and VibrationVolume 2015 Article ID 184648 6 pageshttpdxdoiorg1011552015184648
2 Shock and Vibration
(a) (b)
Figure 1 (a) Striking device listed on the UNE EN 140-7 (b) Alternative striking device
The purpose of this comparison was to study the influence onthe durability of them after undergoing several freeze-thawcycles [9]
When working with building structures the processchanges since the dimensions are greater Furthermore itis important to distinguish between different existing jointsin the structures because a rigid embedment would act as asingle piece against the transmission of the vibration whereasa support would remain the union between pieces unbondedwithout stiff junction attenuating the noise impact [10]When studying the behavior of floor-framing against impactnoise excitations similar to those in the footsteps are ana-lyzed and to do this a known mass is rhythmically droppedfrom a predetermined height Whatever the force of theimpact transmitted to the floor-framing will produce defor-mation of the material in the area occupied by the body slid-ing it from its equilibrium position until the elastic forces ofthe floor-framing return to its initial positionThis originatesa vibration wave which propagates with longitudinal speedthat depends on the nature of the material composing thefloor-framing (the density of the material and the dynamicelastic modulus) where generally for the same density thehigher the elastic modulus the higher the transmission speedand this vibration is in charge of generating the airborne noiseto be controlled [11] Most of the tests carried out in this areahave been assigned to the study of the floating slab as themost appropriate constructive solution to reduce the noiseimpact characterizing the differentmaterials that can be usedas a separator sheet between the rigid surface and the floor-framingrsquos structure
Other investigations focus on the development orimprovement of themeasurement and detection of vibrationsdevices In these cases the materials are not as importantas the sensitivity of the devices and the measurement pro-cedures [12] Some tests are based on the physical conceptof mechanical resonance and attempt to measure the reso-nance frequencies of the different materials However othersare responsible for the development of sensors capable ofdetecting the impact produced on a certain area measuringa physical parameter which might be capacity speed orpressure [13ndash21]
The aim of this paper is to develop an alternative systemof measurement that can detect vibrations produced on
the surface of two different materials (concrete and mortar)analyzing the differences in sensor response for each of theplates and verifying the validity of the system implementedas an alternate measurement method for detecting vibrationsin building structures
2 Methodology
21 Materials That Have Been Used Two tiles were made forthis study one of concrete and another one ofmortar withoutany type of frame to increase its resistance to bending Sincethe measuring device is responsible for detecting transversevibration produced after the impact it is important thatthe tile resembles as much as possible the vibration modelof a stretched membrane Therefore it is essential that thetiles produced work on both main directions and may beconsidered to be plates instead of sheets For this purposethe idea that the thickness must be less than a quarter of thelength of the tile as required by the current EHE-08 was usedas a premise
The dimensions of the tiles were 50 times 50 times 4 cmand the dosage by weight used was 1 3 05 (cementsandwater) in the case of the mortar and 1 2 3 05 (cementsandgravelwater) in the case of the concrete It wasattempted to obtain a soft consistency controlling the amountof water introduced with this once the hardening beginsit evaporates leaving recesses inside which may distort thetest results To prevent this trapped air the concrete and themortar were conveniently vibrated to overcome the cohesiveforces of thematerial and to allow the adaptation to themoldequally distributing the mixture and avoiding significantdifferences in the composition of the tile
22 The Striking Device The striking device listed on theUNE EN 140-7 for testing against impact noise provides thatitmust have five hammers linedwith insulating feet vibrationseparated from each other a distance of approximately 10 cmand each of them periodically hits with a metal mass of 500 gand a ball nose end with a radius of 50mm from a height of40mm (Figure 1(a)) In this work a wooden frame was usedas an alternative whose bases are insulated against vibrationswith an electromagnetic vibrator hanging covered by a steel
Shock and Vibration 3
32
1 5
6
7
4
R15 0R1
R19K2 Q2
BD139
R5K150
R8
18K
Q7BD140
Q3BD140 Q4
2N3055
R12 1K
R16 2K
C1 10 n
R171K
R9 1K
C6 4n7
R10 1KR11 9K2
U1LF355
C51E6 n
R226K
R326K
C41E6 n
R49K2
Q1BD140
R6K300
R7
18KQ8
BD139
Q5BD139
Q62N3055
R13 1KR14 0R1
minus+
+
+
VCC
minusVCC
Vin
Vout
Figure 2 Electrical diagram of the power amplifier
casing containing a field winding where the armature moveslinearly as they vary the frequency of the alternating voltageto which it is connected (Figure 1(b))
23 Design of the Measuring Equipment The measuringequipment consists of several parts Firstly a power amplifierwas designed since the electrical signal from the functiongenerator was not stable enough to be sent directly to thevibrator that strikes the plate The system devised is capableof amplifying signals of frequency below 15 kHz and theamplifier consists of a first stage that allows us to add acontinuous and controlled potential to the signal On theother hand the general characteristics of the amplifier are asfollows voltage gain factor is 10 themaximumoutput currentis 1 A the maximum output voltage is 30V short-circuitprotection and amplification without appreciable distortionare from 0Hz to 10 kHz The generator and the amplifierapply signals of frequency very stable and variable which canbe regulated at all times See the electrical diagram of theamplifier in Figure 2
Moreover a sensor was designed that was capable ofmeasuring the transverse deformation produced when thetile is struck on its upper face knowing the striking energyselected with the help of the vibrator The sensor consists of acondenser that is part of a digital self-oscillating circuit Theoutput of this circuit is connected to an FM Demodulatortuned to a frequency which is the base frequency of the self-oscillating circuit The diagram of the sensor is shown inFigure 3
As the capacity of the condenser depends only on itsgeometry and the matter permittivity between plates if thearea between its plates and the dielectric is kept constantthen its capacity will only vary depending on the separationbetween the plates One of the plates of the transducer isfixed in the middle of the plate material (as can be seen inFigure 4) while the other one is fixed on the flat reference
TransducerSelf-oscillating
circuitFM
demodulator Output
Figure 3 Diagram of the sensor
surface so that when the impact occurs the transversedeformation produced by the vibration varies the capacity ofthe condenser whose signal is recorded
The self-oscillating circuit is constructed such that itsnatural oscillation frequency is sufficiently high in thiscase 33MHz On the other hand the size of the platesmust always be less than or equal to half of a wavelengthso that the sensor sensitivity corresponds to the measurestaken therefore knowing the propagation speed of thetransverse wave in the medium can set the dimensions ofthe condenser plates To calculate the propagation veloci-ties the following formulas were used for concrete (i) andmortar (ii)
(i) 119881119905= radic
119864119889sdot 119892
120574119867
sdot
12 sdot (1 + ])
= 2450ms
(ii) 119881119905= radic
119864
2120574119872sdot (1 + ])
= 1225ms
(1)
where 119864119889is the dynamic modulus of elasticity of concrete
(323 times 109 kgm2) 119864 is the elastic modulus of mortar (9 times106MPa) 120574
119867is the concrete density (2200 kgm3) 120574
119872is
the mortar density (2500 kgm3) 119892 is acceleration of gravity(98ms2) and ] is the Poisson coefficient (02) Taking intoaccount that condenser plates are 6 cm per side the length of
4 Shock and Vibration
Generator of functions Amplifier
Striking device
Tile (50 times 50 cm)
Sensor (transducer)
CH-1
CH-2
Oscilloscope
Electronics of the sensor
Vibrator
Figure 4 Diagram of the measuring equipment
the transverse wave should be at most 12 cmThus we obtaina frequency (119891) for concrete (i) and mortar (ii) as follows
(ii) V = 120582 sdot 119891 997904rArr 1225 = 012 sdot 119891 997904rArr 119891 = 10208Hz(2)
That is within the range of our oscillating circuitFinally the variation in the capacity of the transducer
reproduces the concrete or mortar sheet deformation andthis leads to the output of the self-oscillating circuit a fre-quency modulated signal The frequency modulation is dueto transverse vibration so adding the demodulator circuita signal proportional to the transverse deformation of themortar or concrete sheet is obtained at the output of thecircuit at each time point This signal was collected with thehelp of an oscilloscope (Figure 4)
3 Results and Discussion
Figure 5 shows the excitation signal with a frequency of10000Hz With this we have obtained the sensor responseand its analysis of harmonic numbers for concrete (Figure 6)and mortar (Figure 7) tiles As can be seen the sensorresponse and the harmonic analysis for a prefixed frequencyof work show differences between the tiles of concrete andmortar The data that were used for the analysis harmonicswere treated using a software programmed capable of cal-culating the discrete Fourier transform thereby obtaining arepresentation in the frequency domain with the originalfunction being a function in the time domain
As can be appreciated in the graphics the sensitivity ofthe sensor is able to differentiate the modes of transmissionof the impact between the different materials being higherin the case of concrete than in the case of mortar which isconsistent with the previous theoretical calculations
Exci
tatio
n am
plitu
de (V
)
minus25
minus20
minus15
minus10
minus5
0
0 100 200 300 400 500
5
10
15
20
Time (120583s)
Figure 5 Excitation signal with a frequency of 10000Hz
4 Conclusions
From the data obtained it can be stated that we havedeveloped on the one hand a system that is able to producemeasurable and controllable vibrations and on the otherhand a transducer that is able to appreciate the frequencyvariations caused by the striking device giving a signal inresponse which is easily analyzable
Studying the harmonic content of the sensor responsein the cases of concrete and mortar clearly differentiatedresults has been obtained The frequency of response hasbeen higher in the case of concrete This is consistent withthe theoretical results obtained in (2) and therefore verifiesthe validity of the equipment The developed system can beimproved to achieve higher sensitivity and sharper responses
Shock and Vibration 5
Sens
or re
spon
se (V
)
minus1
0
0 100 200 300 400 500
1
2
3
4
5
Time (120583s)
(a)A
mpl
itude
(V)
Harmonic number
05
04
03
02
01
0
0 2 4 6 8 10 12 14 16 18
(b)
Figure 6 Response concrete tile (a) Response of the oscillator (b) Analysis gives harmonics of the sensor response
Sens
or re
spon
se (V
)
minus1
0
0 100 200 300 400 500
1
2
3
4
5
Time (120583s)
(a)
Am
plitu
de (V
)
Harmonic number
05
04
03
02
01
0
0 2 4 6 8 10 12 14 16 18
(b)
Figure 7 Response mortar tile (a) Response of the oscillator (b) Analysis gives harmonics of the sensor response
Thus through a more thorough process the system couldbe used as standard method for the study of vibrations andacoustic insulation against impact noise
Conflict of Interests
The authors declare that there is no conflict of interestsregarding the publication of this paper
References
[1] Espana Codigo Tecnico de la Edificacion Boletın Oficial delEstado 2006
[2] Espana ldquoInstruccion de Hormigon Estructuralrdquo Boletın Oficialdel Estado num 203 2008
[3] M Tarabini S Solbiati G Moschioni B Saggin and DScaccabarozzi ldquoAnalysis of non-linear response of the humanbody to vertical whole-body vibrationrdquo Ergonomics vol 57 no11 pp 1711ndash1723 2014
6 Shock and Vibration
[4] A Nagy ldquoDetermination of E-modulus of young concretewith nondestructive methodrdquo Journal of Materials in CivilEngineering vol 9 no 1 pp 15ndash20 1997
[5] D Dai and Q He ldquoStructure damage localization with ultra-sonic guided waves based on a time-frequency methodrdquo SignalProcessing vol 96 pp 21ndash28 2014
[6] K Marar O Eren and T Celik ldquoRelacion entre la tenacidad aflexion y la energıa de impacto en hormigones de alta resistenciareforzados con fibrasrdquo Materiales de Construccion vol 51 no262 pp 5ndash13 2001
[7] L-Q ChenW-J Zhao and J W Zu ldquoSimulations of transversevibrations of an axially moving string a modified differenceapproachrdquo Applied Mathematics and Computation vol 166 no3 pp 596ndash607 2005
[8] L-Q Chen and H Ding ldquoSteady-state transverse response incoupled planar vibration of axially moving viscoelastic beamsrdquoTransactions of the ASMEmdashJournal of Vibration and Acousticsvol 132 no 1 Article ID 01100919 9 pages 2010
[9] E K Schrader ldquoImpact resistance and test procedure forconcreterdquo Journal of the American Concrete Institute vol 78 no2 pp 141ndash146 1981
[10] A H Hosseinloo F F Yap and L Y Lim ldquoDesign and analysisof shock and random vibration isolation system for a discretemodel of submerged jet impingement cooling systemrdquo Journalof Vibration and Control vol 21 no 3 pp 468ndash482 2015
[11] J WuW Lei QWu YWang and L Ma ldquoTransverse vibrationcharacteristics and stability of a moving membrane with elasticsupportsrdquo Journal of Low Frequency Noise Vibration and ActiveControl vol 33 no 1 pp 65ndash78 2014
[12] M Ghajari Z Sharif-Khodaei M H Aliabadi and A ApicellaldquoIdentification of impact force for smart composite stiffenedpanelsrdquo Smart Materials and Structures vol 22 no 8 ArticleID 085014 2013
[13] R Makowski and R Zimroz ldquoNew techniques of local damagedetection in machinery based on stochastic modelling usingadaptive Schur filterrdquo Applied Acoustics vol 77 pp 130ndash1372014
[14] D W T Wundersitz P B Gastin C Richter S J Robertsonand K J Netto ldquoValidity of a trunk-mounted accelerometer toassess peak accelerations duringwalking jogging and runningrdquoEuropean Journal of Sport Science vol 15 no 5 pp 382ndash3902014
[15] R Klopper M Okuma and J Kruger ldquoA new process formeasuring complete inertia propertiesrdquo MTZ Worldwide vol74 no 3 pp 40ndash44 2013
[16] L-J Dong X-B Li Z-L Zhou G-H Chen and J Ma ldquoThree-dimensional analytical solution of acoustic emission sourcelocation for cuboid monitoring network without pre-measuredwave velocityrdquo Transactions of Nonferrous Metals Society ofChina vol 25 no 1 pp 293ndash302 2015
[17] L Dong X Li and G Xie ldquoAn analytical solution for acousticemission source location for known P wave velocity systemrdquoMathematical Problems in Engineering vol 2014 Article ID290686 6 pages 2014
[18] Q-Y Li L-J Dong X-B Li Z-Q Yin andX-L Liu ldquoEffects ofsonic speed on location accuracy of acoustic emission source inrocksrdquo Transactions of Nonferrous Metals Society of China vol21 no 12 pp 2719ndash2726 2011
[19] L-J Dong and X-B Li ldquoAn efficient closed-form solutionfor acoustic emission source location in threedimensionalstructuresrdquo AIP Advances vol 4 no 2 Article ID 027110 2014
[20] J A Somolinos R Morales A Garcıa and C Moron ldquoPiezo-electric sensors system for impact detectingrdquo Sensor Letters vol11 no 1 pp 128ndash130 2013
[21] J A Somolinos R Morales A Lopez and C Moron ldquoA newself-calibrated procedure for impact detection and location onflat surfacesrdquo Sensors vol 13 no 6 pp 7104ndash7120 2013
Figure 1 (a) Striking device listed on the UNE EN 140-7 (b) Alternative striking device
The purpose of this comparison was to study the influence onthe durability of them after undergoing several freeze-thawcycles [9]
When working with building structures the processchanges since the dimensions are greater Furthermore itis important to distinguish between different existing jointsin the structures because a rigid embedment would act as asingle piece against the transmission of the vibration whereasa support would remain the union between pieces unbondedwithout stiff junction attenuating the noise impact [10]When studying the behavior of floor-framing against impactnoise excitations similar to those in the footsteps are ana-lyzed and to do this a known mass is rhythmically droppedfrom a predetermined height Whatever the force of theimpact transmitted to the floor-framing will produce defor-mation of the material in the area occupied by the body slid-ing it from its equilibrium position until the elastic forces ofthe floor-framing return to its initial positionThis originatesa vibration wave which propagates with longitudinal speedthat depends on the nature of the material composing thefloor-framing (the density of the material and the dynamicelastic modulus) where generally for the same density thehigher the elastic modulus the higher the transmission speedand this vibration is in charge of generating the airborne noiseto be controlled [11] Most of the tests carried out in this areahave been assigned to the study of the floating slab as themost appropriate constructive solution to reduce the noiseimpact characterizing the differentmaterials that can be usedas a separator sheet between the rigid surface and the floor-framingrsquos structure
Other investigations focus on the development orimprovement of themeasurement and detection of vibrationsdevices In these cases the materials are not as importantas the sensitivity of the devices and the measurement pro-cedures [12] Some tests are based on the physical conceptof mechanical resonance and attempt to measure the reso-nance frequencies of the different materials However othersare responsible for the development of sensors capable ofdetecting the impact produced on a certain area measuringa physical parameter which might be capacity speed orpressure [13ndash21]
The aim of this paper is to develop an alternative systemof measurement that can detect vibrations produced on
the surface of two different materials (concrete and mortar)analyzing the differences in sensor response for each of theplates and verifying the validity of the system implementedas an alternate measurement method for detecting vibrationsin building structures
2 Methodology
21 Materials That Have Been Used Two tiles were made forthis study one of concrete and another one ofmortar withoutany type of frame to increase its resistance to bending Sincethe measuring device is responsible for detecting transversevibration produced after the impact it is important thatthe tile resembles as much as possible the vibration modelof a stretched membrane Therefore it is essential that thetiles produced work on both main directions and may beconsidered to be plates instead of sheets For this purposethe idea that the thickness must be less than a quarter of thelength of the tile as required by the current EHE-08 was usedas a premise
The dimensions of the tiles were 50 times 50 times 4 cmand the dosage by weight used was 1 3 05 (cementsandwater) in the case of the mortar and 1 2 3 05 (cementsandgravelwater) in the case of the concrete It wasattempted to obtain a soft consistency controlling the amountof water introduced with this once the hardening beginsit evaporates leaving recesses inside which may distort thetest results To prevent this trapped air the concrete and themortar were conveniently vibrated to overcome the cohesiveforces of thematerial and to allow the adaptation to themoldequally distributing the mixture and avoiding significantdifferences in the composition of the tile
22 The Striking Device The striking device listed on theUNE EN 140-7 for testing against impact noise provides thatitmust have five hammers linedwith insulating feet vibrationseparated from each other a distance of approximately 10 cmand each of them periodically hits with a metal mass of 500 gand a ball nose end with a radius of 50mm from a height of40mm (Figure 1(a)) In this work a wooden frame was usedas an alternative whose bases are insulated against vibrationswith an electromagnetic vibrator hanging covered by a steel
Shock and Vibration 3
32
1 5
6
7
4
R15 0R1
R19K2 Q2
BD139
R5K150
R8
18K
Q7BD140
Q3BD140 Q4
2N3055
R12 1K
R16 2K
C1 10 n
R171K
R9 1K
C6 4n7
R10 1KR11 9K2
U1LF355
C51E6 n
R226K
R326K
C41E6 n
R49K2
Q1BD140
R6K300
R7
18KQ8
BD139
Q5BD139
Q62N3055
R13 1KR14 0R1
minus+
+
+
VCC
minusVCC
Vin
Vout
Figure 2 Electrical diagram of the power amplifier
casing containing a field winding where the armature moveslinearly as they vary the frequency of the alternating voltageto which it is connected (Figure 1(b))
23 Design of the Measuring Equipment The measuringequipment consists of several parts Firstly a power amplifierwas designed since the electrical signal from the functiongenerator was not stable enough to be sent directly to thevibrator that strikes the plate The system devised is capableof amplifying signals of frequency below 15 kHz and theamplifier consists of a first stage that allows us to add acontinuous and controlled potential to the signal On theother hand the general characteristics of the amplifier are asfollows voltage gain factor is 10 themaximumoutput currentis 1 A the maximum output voltage is 30V short-circuitprotection and amplification without appreciable distortionare from 0Hz to 10 kHz The generator and the amplifierapply signals of frequency very stable and variable which canbe regulated at all times See the electrical diagram of theamplifier in Figure 2
Moreover a sensor was designed that was capable ofmeasuring the transverse deformation produced when thetile is struck on its upper face knowing the striking energyselected with the help of the vibrator The sensor consists of acondenser that is part of a digital self-oscillating circuit Theoutput of this circuit is connected to an FM Demodulatortuned to a frequency which is the base frequency of the self-oscillating circuit The diagram of the sensor is shown inFigure 3
As the capacity of the condenser depends only on itsgeometry and the matter permittivity between plates if thearea between its plates and the dielectric is kept constantthen its capacity will only vary depending on the separationbetween the plates One of the plates of the transducer isfixed in the middle of the plate material (as can be seen inFigure 4) while the other one is fixed on the flat reference
TransducerSelf-oscillating
circuitFM
demodulator Output
Figure 3 Diagram of the sensor
surface so that when the impact occurs the transversedeformation produced by the vibration varies the capacity ofthe condenser whose signal is recorded
The self-oscillating circuit is constructed such that itsnatural oscillation frequency is sufficiently high in thiscase 33MHz On the other hand the size of the platesmust always be less than or equal to half of a wavelengthso that the sensor sensitivity corresponds to the measurestaken therefore knowing the propagation speed of thetransverse wave in the medium can set the dimensions ofthe condenser plates To calculate the propagation veloci-ties the following formulas were used for concrete (i) andmortar (ii)
(i) 119881119905= radic
119864119889sdot 119892
120574119867
sdot
12 sdot (1 + ])
= 2450ms
(ii) 119881119905= radic
119864
2120574119872sdot (1 + ])
= 1225ms
(1)
where 119864119889is the dynamic modulus of elasticity of concrete
(323 times 109 kgm2) 119864 is the elastic modulus of mortar (9 times106MPa) 120574
119867is the concrete density (2200 kgm3) 120574
119872is
the mortar density (2500 kgm3) 119892 is acceleration of gravity(98ms2) and ] is the Poisson coefficient (02) Taking intoaccount that condenser plates are 6 cm per side the length of
4 Shock and Vibration
Generator of functions Amplifier
Striking device
Tile (50 times 50 cm)
Sensor (transducer)
CH-1
CH-2
Oscilloscope
Electronics of the sensor
Vibrator
Figure 4 Diagram of the measuring equipment
the transverse wave should be at most 12 cmThus we obtaina frequency (119891) for concrete (i) and mortar (ii) as follows
(ii) V = 120582 sdot 119891 997904rArr 1225 = 012 sdot 119891 997904rArr 119891 = 10208Hz(2)
That is within the range of our oscillating circuitFinally the variation in the capacity of the transducer
reproduces the concrete or mortar sheet deformation andthis leads to the output of the self-oscillating circuit a fre-quency modulated signal The frequency modulation is dueto transverse vibration so adding the demodulator circuita signal proportional to the transverse deformation of themortar or concrete sheet is obtained at the output of thecircuit at each time point This signal was collected with thehelp of an oscilloscope (Figure 4)
3 Results and Discussion
Figure 5 shows the excitation signal with a frequency of10000Hz With this we have obtained the sensor responseand its analysis of harmonic numbers for concrete (Figure 6)and mortar (Figure 7) tiles As can be seen the sensorresponse and the harmonic analysis for a prefixed frequencyof work show differences between the tiles of concrete andmortar The data that were used for the analysis harmonicswere treated using a software programmed capable of cal-culating the discrete Fourier transform thereby obtaining arepresentation in the frequency domain with the originalfunction being a function in the time domain
As can be appreciated in the graphics the sensitivity ofthe sensor is able to differentiate the modes of transmissionof the impact between the different materials being higherin the case of concrete than in the case of mortar which isconsistent with the previous theoretical calculations
Exci
tatio
n am
plitu
de (V
)
minus25
minus20
minus15
minus10
minus5
0
0 100 200 300 400 500
5
10
15
20
Time (120583s)
Figure 5 Excitation signal with a frequency of 10000Hz
4 Conclusions
From the data obtained it can be stated that we havedeveloped on the one hand a system that is able to producemeasurable and controllable vibrations and on the otherhand a transducer that is able to appreciate the frequencyvariations caused by the striking device giving a signal inresponse which is easily analyzable
Studying the harmonic content of the sensor responsein the cases of concrete and mortar clearly differentiatedresults has been obtained The frequency of response hasbeen higher in the case of concrete This is consistent withthe theoretical results obtained in (2) and therefore verifiesthe validity of the equipment The developed system can beimproved to achieve higher sensitivity and sharper responses
Shock and Vibration 5
Sens
or re
spon
se (V
)
minus1
0
0 100 200 300 400 500
1
2
3
4
5
Time (120583s)
(a)A
mpl
itude
(V)
Harmonic number
05
04
03
02
01
0
0 2 4 6 8 10 12 14 16 18
(b)
Figure 6 Response concrete tile (a) Response of the oscillator (b) Analysis gives harmonics of the sensor response
Sens
or re
spon
se (V
)
minus1
0
0 100 200 300 400 500
1
2
3
4
5
Time (120583s)
(a)
Am
plitu
de (V
)
Harmonic number
05
04
03
02
01
0
0 2 4 6 8 10 12 14 16 18
(b)
Figure 7 Response mortar tile (a) Response of the oscillator (b) Analysis gives harmonics of the sensor response
Thus through a more thorough process the system couldbe used as standard method for the study of vibrations andacoustic insulation against impact noise
Conflict of Interests
The authors declare that there is no conflict of interestsregarding the publication of this paper
References
[1] Espana Codigo Tecnico de la Edificacion Boletın Oficial delEstado 2006
[2] Espana ldquoInstruccion de Hormigon Estructuralrdquo Boletın Oficialdel Estado num 203 2008
[3] M Tarabini S Solbiati G Moschioni B Saggin and DScaccabarozzi ldquoAnalysis of non-linear response of the humanbody to vertical whole-body vibrationrdquo Ergonomics vol 57 no11 pp 1711ndash1723 2014
6 Shock and Vibration
[4] A Nagy ldquoDetermination of E-modulus of young concretewith nondestructive methodrdquo Journal of Materials in CivilEngineering vol 9 no 1 pp 15ndash20 1997
[5] D Dai and Q He ldquoStructure damage localization with ultra-sonic guided waves based on a time-frequency methodrdquo SignalProcessing vol 96 pp 21ndash28 2014
[6] K Marar O Eren and T Celik ldquoRelacion entre la tenacidad aflexion y la energıa de impacto en hormigones de alta resistenciareforzados con fibrasrdquo Materiales de Construccion vol 51 no262 pp 5ndash13 2001
[7] L-Q ChenW-J Zhao and J W Zu ldquoSimulations of transversevibrations of an axially moving string a modified differenceapproachrdquo Applied Mathematics and Computation vol 166 no3 pp 596ndash607 2005
[8] L-Q Chen and H Ding ldquoSteady-state transverse response incoupled planar vibration of axially moving viscoelastic beamsrdquoTransactions of the ASMEmdashJournal of Vibration and Acousticsvol 132 no 1 Article ID 01100919 9 pages 2010
[9] E K Schrader ldquoImpact resistance and test procedure forconcreterdquo Journal of the American Concrete Institute vol 78 no2 pp 141ndash146 1981
[10] A H Hosseinloo F F Yap and L Y Lim ldquoDesign and analysisof shock and random vibration isolation system for a discretemodel of submerged jet impingement cooling systemrdquo Journalof Vibration and Control vol 21 no 3 pp 468ndash482 2015
[11] J WuW Lei QWu YWang and L Ma ldquoTransverse vibrationcharacteristics and stability of a moving membrane with elasticsupportsrdquo Journal of Low Frequency Noise Vibration and ActiveControl vol 33 no 1 pp 65ndash78 2014
[12] M Ghajari Z Sharif-Khodaei M H Aliabadi and A ApicellaldquoIdentification of impact force for smart composite stiffenedpanelsrdquo Smart Materials and Structures vol 22 no 8 ArticleID 085014 2013
[13] R Makowski and R Zimroz ldquoNew techniques of local damagedetection in machinery based on stochastic modelling usingadaptive Schur filterrdquo Applied Acoustics vol 77 pp 130ndash1372014
[14] D W T Wundersitz P B Gastin C Richter S J Robertsonand K J Netto ldquoValidity of a trunk-mounted accelerometer toassess peak accelerations duringwalking jogging and runningrdquoEuropean Journal of Sport Science vol 15 no 5 pp 382ndash3902014
[15] R Klopper M Okuma and J Kruger ldquoA new process formeasuring complete inertia propertiesrdquo MTZ Worldwide vol74 no 3 pp 40ndash44 2013
[16] L-J Dong X-B Li Z-L Zhou G-H Chen and J Ma ldquoThree-dimensional analytical solution of acoustic emission sourcelocation for cuboid monitoring network without pre-measuredwave velocityrdquo Transactions of Nonferrous Metals Society ofChina vol 25 no 1 pp 293ndash302 2015
[17] L Dong X Li and G Xie ldquoAn analytical solution for acousticemission source location for known P wave velocity systemrdquoMathematical Problems in Engineering vol 2014 Article ID290686 6 pages 2014
[18] Q-Y Li L-J Dong X-B Li Z-Q Yin andX-L Liu ldquoEffects ofsonic speed on location accuracy of acoustic emission source inrocksrdquo Transactions of Nonferrous Metals Society of China vol21 no 12 pp 2719ndash2726 2011
[19] L-J Dong and X-B Li ldquoAn efficient closed-form solutionfor acoustic emission source location in threedimensionalstructuresrdquo AIP Advances vol 4 no 2 Article ID 027110 2014
[20] J A Somolinos R Morales A Garcıa and C Moron ldquoPiezo-electric sensors system for impact detectingrdquo Sensor Letters vol11 no 1 pp 128ndash130 2013
[21] J A Somolinos R Morales A Lopez and C Moron ldquoA newself-calibrated procedure for impact detection and location onflat surfacesrdquo Sensors vol 13 no 6 pp 7104ndash7120 2013
Figure 2 Electrical diagram of the power amplifier
casing containing a field winding where the armature moveslinearly as they vary the frequency of the alternating voltageto which it is connected (Figure 1(b))
23 Design of the Measuring Equipment The measuringequipment consists of several parts Firstly a power amplifierwas designed since the electrical signal from the functiongenerator was not stable enough to be sent directly to thevibrator that strikes the plate The system devised is capableof amplifying signals of frequency below 15 kHz and theamplifier consists of a first stage that allows us to add acontinuous and controlled potential to the signal On theother hand the general characteristics of the amplifier are asfollows voltage gain factor is 10 themaximumoutput currentis 1 A the maximum output voltage is 30V short-circuitprotection and amplification without appreciable distortionare from 0Hz to 10 kHz The generator and the amplifierapply signals of frequency very stable and variable which canbe regulated at all times See the electrical diagram of theamplifier in Figure 2
Moreover a sensor was designed that was capable ofmeasuring the transverse deformation produced when thetile is struck on its upper face knowing the striking energyselected with the help of the vibrator The sensor consists of acondenser that is part of a digital self-oscillating circuit Theoutput of this circuit is connected to an FM Demodulatortuned to a frequency which is the base frequency of the self-oscillating circuit The diagram of the sensor is shown inFigure 3
As the capacity of the condenser depends only on itsgeometry and the matter permittivity between plates if thearea between its plates and the dielectric is kept constantthen its capacity will only vary depending on the separationbetween the plates One of the plates of the transducer isfixed in the middle of the plate material (as can be seen inFigure 4) while the other one is fixed on the flat reference
TransducerSelf-oscillating
circuitFM
demodulator Output
Figure 3 Diagram of the sensor
surface so that when the impact occurs the transversedeformation produced by the vibration varies the capacity ofthe condenser whose signal is recorded
The self-oscillating circuit is constructed such that itsnatural oscillation frequency is sufficiently high in thiscase 33MHz On the other hand the size of the platesmust always be less than or equal to half of a wavelengthso that the sensor sensitivity corresponds to the measurestaken therefore knowing the propagation speed of thetransverse wave in the medium can set the dimensions ofthe condenser plates To calculate the propagation veloci-ties the following formulas were used for concrete (i) andmortar (ii)
(i) 119881119905= radic
119864119889sdot 119892
120574119867
sdot
12 sdot (1 + ])
= 2450ms
(ii) 119881119905= radic
119864
2120574119872sdot (1 + ])
= 1225ms
(1)
where 119864119889is the dynamic modulus of elasticity of concrete
(323 times 109 kgm2) 119864 is the elastic modulus of mortar (9 times106MPa) 120574
119867is the concrete density (2200 kgm3) 120574
119872is
the mortar density (2500 kgm3) 119892 is acceleration of gravity(98ms2) and ] is the Poisson coefficient (02) Taking intoaccount that condenser plates are 6 cm per side the length of
4 Shock and Vibration
Generator of functions Amplifier
Striking device
Tile (50 times 50 cm)
Sensor (transducer)
CH-1
CH-2
Oscilloscope
Electronics of the sensor
Vibrator
Figure 4 Diagram of the measuring equipment
the transverse wave should be at most 12 cmThus we obtaina frequency (119891) for concrete (i) and mortar (ii) as follows
(ii) V = 120582 sdot 119891 997904rArr 1225 = 012 sdot 119891 997904rArr 119891 = 10208Hz(2)
That is within the range of our oscillating circuitFinally the variation in the capacity of the transducer
reproduces the concrete or mortar sheet deformation andthis leads to the output of the self-oscillating circuit a fre-quency modulated signal The frequency modulation is dueto transverse vibration so adding the demodulator circuita signal proportional to the transverse deformation of themortar or concrete sheet is obtained at the output of thecircuit at each time point This signal was collected with thehelp of an oscilloscope (Figure 4)
3 Results and Discussion
Figure 5 shows the excitation signal with a frequency of10000Hz With this we have obtained the sensor responseand its analysis of harmonic numbers for concrete (Figure 6)and mortar (Figure 7) tiles As can be seen the sensorresponse and the harmonic analysis for a prefixed frequencyof work show differences between the tiles of concrete andmortar The data that were used for the analysis harmonicswere treated using a software programmed capable of cal-culating the discrete Fourier transform thereby obtaining arepresentation in the frequency domain with the originalfunction being a function in the time domain
As can be appreciated in the graphics the sensitivity ofthe sensor is able to differentiate the modes of transmissionof the impact between the different materials being higherin the case of concrete than in the case of mortar which isconsistent with the previous theoretical calculations
Exci
tatio
n am
plitu
de (V
)
minus25
minus20
minus15
minus10
minus5
0
0 100 200 300 400 500
5
10
15
20
Time (120583s)
Figure 5 Excitation signal with a frequency of 10000Hz
4 Conclusions
From the data obtained it can be stated that we havedeveloped on the one hand a system that is able to producemeasurable and controllable vibrations and on the otherhand a transducer that is able to appreciate the frequencyvariations caused by the striking device giving a signal inresponse which is easily analyzable
Studying the harmonic content of the sensor responsein the cases of concrete and mortar clearly differentiatedresults has been obtained The frequency of response hasbeen higher in the case of concrete This is consistent withthe theoretical results obtained in (2) and therefore verifiesthe validity of the equipment The developed system can beimproved to achieve higher sensitivity and sharper responses
Shock and Vibration 5
Sens
or re
spon
se (V
)
minus1
0
0 100 200 300 400 500
1
2
3
4
5
Time (120583s)
(a)A
mpl
itude
(V)
Harmonic number
05
04
03
02
01
0
0 2 4 6 8 10 12 14 16 18
(b)
Figure 6 Response concrete tile (a) Response of the oscillator (b) Analysis gives harmonics of the sensor response
Sens
or re
spon
se (V
)
minus1
0
0 100 200 300 400 500
1
2
3
4
5
Time (120583s)
(a)
Am
plitu
de (V
)
Harmonic number
05
04
03
02
01
0
0 2 4 6 8 10 12 14 16 18
(b)
Figure 7 Response mortar tile (a) Response of the oscillator (b) Analysis gives harmonics of the sensor response
Thus through a more thorough process the system couldbe used as standard method for the study of vibrations andacoustic insulation against impact noise
Conflict of Interests
The authors declare that there is no conflict of interestsregarding the publication of this paper
References
[1] Espana Codigo Tecnico de la Edificacion Boletın Oficial delEstado 2006
[2] Espana ldquoInstruccion de Hormigon Estructuralrdquo Boletın Oficialdel Estado num 203 2008
[3] M Tarabini S Solbiati G Moschioni B Saggin and DScaccabarozzi ldquoAnalysis of non-linear response of the humanbody to vertical whole-body vibrationrdquo Ergonomics vol 57 no11 pp 1711ndash1723 2014
6 Shock and Vibration
[4] A Nagy ldquoDetermination of E-modulus of young concretewith nondestructive methodrdquo Journal of Materials in CivilEngineering vol 9 no 1 pp 15ndash20 1997
[5] D Dai and Q He ldquoStructure damage localization with ultra-sonic guided waves based on a time-frequency methodrdquo SignalProcessing vol 96 pp 21ndash28 2014
[6] K Marar O Eren and T Celik ldquoRelacion entre la tenacidad aflexion y la energıa de impacto en hormigones de alta resistenciareforzados con fibrasrdquo Materiales de Construccion vol 51 no262 pp 5ndash13 2001
[7] L-Q ChenW-J Zhao and J W Zu ldquoSimulations of transversevibrations of an axially moving string a modified differenceapproachrdquo Applied Mathematics and Computation vol 166 no3 pp 596ndash607 2005
[8] L-Q Chen and H Ding ldquoSteady-state transverse response incoupled planar vibration of axially moving viscoelastic beamsrdquoTransactions of the ASMEmdashJournal of Vibration and Acousticsvol 132 no 1 Article ID 01100919 9 pages 2010
[9] E K Schrader ldquoImpact resistance and test procedure forconcreterdquo Journal of the American Concrete Institute vol 78 no2 pp 141ndash146 1981
[10] A H Hosseinloo F F Yap and L Y Lim ldquoDesign and analysisof shock and random vibration isolation system for a discretemodel of submerged jet impingement cooling systemrdquo Journalof Vibration and Control vol 21 no 3 pp 468ndash482 2015
[11] J WuW Lei QWu YWang and L Ma ldquoTransverse vibrationcharacteristics and stability of a moving membrane with elasticsupportsrdquo Journal of Low Frequency Noise Vibration and ActiveControl vol 33 no 1 pp 65ndash78 2014
[12] M Ghajari Z Sharif-Khodaei M H Aliabadi and A ApicellaldquoIdentification of impact force for smart composite stiffenedpanelsrdquo Smart Materials and Structures vol 22 no 8 ArticleID 085014 2013
[13] R Makowski and R Zimroz ldquoNew techniques of local damagedetection in machinery based on stochastic modelling usingadaptive Schur filterrdquo Applied Acoustics vol 77 pp 130ndash1372014
[14] D W T Wundersitz P B Gastin C Richter S J Robertsonand K J Netto ldquoValidity of a trunk-mounted accelerometer toassess peak accelerations duringwalking jogging and runningrdquoEuropean Journal of Sport Science vol 15 no 5 pp 382ndash3902014
[15] R Klopper M Okuma and J Kruger ldquoA new process formeasuring complete inertia propertiesrdquo MTZ Worldwide vol74 no 3 pp 40ndash44 2013
[16] L-J Dong X-B Li Z-L Zhou G-H Chen and J Ma ldquoThree-dimensional analytical solution of acoustic emission sourcelocation for cuboid monitoring network without pre-measuredwave velocityrdquo Transactions of Nonferrous Metals Society ofChina vol 25 no 1 pp 293ndash302 2015
[17] L Dong X Li and G Xie ldquoAn analytical solution for acousticemission source location for known P wave velocity systemrdquoMathematical Problems in Engineering vol 2014 Article ID290686 6 pages 2014
[18] Q-Y Li L-J Dong X-B Li Z-Q Yin andX-L Liu ldquoEffects ofsonic speed on location accuracy of acoustic emission source inrocksrdquo Transactions of Nonferrous Metals Society of China vol21 no 12 pp 2719ndash2726 2011
[19] L-J Dong and X-B Li ldquoAn efficient closed-form solutionfor acoustic emission source location in threedimensionalstructuresrdquo AIP Advances vol 4 no 2 Article ID 027110 2014
[20] J A Somolinos R Morales A Garcıa and C Moron ldquoPiezo-electric sensors system for impact detectingrdquo Sensor Letters vol11 no 1 pp 128ndash130 2013
[21] J A Somolinos R Morales A Lopez and C Moron ldquoA newself-calibrated procedure for impact detection and location onflat surfacesrdquo Sensors vol 13 no 6 pp 7104ndash7120 2013
(ii) V = 120582 sdot 119891 997904rArr 1225 = 012 sdot 119891 997904rArr 119891 = 10208Hz(2)
That is within the range of our oscillating circuitFinally the variation in the capacity of the transducer
reproduces the concrete or mortar sheet deformation andthis leads to the output of the self-oscillating circuit a fre-quency modulated signal The frequency modulation is dueto transverse vibration so adding the demodulator circuita signal proportional to the transverse deformation of themortar or concrete sheet is obtained at the output of thecircuit at each time point This signal was collected with thehelp of an oscilloscope (Figure 4)
3 Results and Discussion
Figure 5 shows the excitation signal with a frequency of10000Hz With this we have obtained the sensor responseand its analysis of harmonic numbers for concrete (Figure 6)and mortar (Figure 7) tiles As can be seen the sensorresponse and the harmonic analysis for a prefixed frequencyof work show differences between the tiles of concrete andmortar The data that were used for the analysis harmonicswere treated using a software programmed capable of cal-culating the discrete Fourier transform thereby obtaining arepresentation in the frequency domain with the originalfunction being a function in the time domain
As can be appreciated in the graphics the sensitivity ofthe sensor is able to differentiate the modes of transmissionof the impact between the different materials being higherin the case of concrete than in the case of mortar which isconsistent with the previous theoretical calculations
Exci
tatio
n am
plitu
de (V
)
minus25
minus20
minus15
minus10
minus5
0
0 100 200 300 400 500
5
10
15
20
Time (120583s)
Figure 5 Excitation signal with a frequency of 10000Hz
4 Conclusions
From the data obtained it can be stated that we havedeveloped on the one hand a system that is able to producemeasurable and controllable vibrations and on the otherhand a transducer that is able to appreciate the frequencyvariations caused by the striking device giving a signal inresponse which is easily analyzable
Studying the harmonic content of the sensor responsein the cases of concrete and mortar clearly differentiatedresults has been obtained The frequency of response hasbeen higher in the case of concrete This is consistent withthe theoretical results obtained in (2) and therefore verifiesthe validity of the equipment The developed system can beimproved to achieve higher sensitivity and sharper responses
Shock and Vibration 5
Sens
or re
spon
se (V
)
minus1
0
0 100 200 300 400 500
1
2
3
4
5
Time (120583s)
(a)A
mpl
itude
(V)
Harmonic number
05
04
03
02
01
0
0 2 4 6 8 10 12 14 16 18
(b)
Figure 6 Response concrete tile (a) Response of the oscillator (b) Analysis gives harmonics of the sensor response
Sens
or re
spon
se (V
)
minus1
0
0 100 200 300 400 500
1
2
3
4
5
Time (120583s)
(a)
Am
plitu
de (V
)
Harmonic number
05
04
03
02
01
0
0 2 4 6 8 10 12 14 16 18
(b)
Figure 7 Response mortar tile (a) Response of the oscillator (b) Analysis gives harmonics of the sensor response
Thus through a more thorough process the system couldbe used as standard method for the study of vibrations andacoustic insulation against impact noise
Conflict of Interests
The authors declare that there is no conflict of interestsregarding the publication of this paper
References
[1] Espana Codigo Tecnico de la Edificacion Boletın Oficial delEstado 2006
[2] Espana ldquoInstruccion de Hormigon Estructuralrdquo Boletın Oficialdel Estado num 203 2008
[3] M Tarabini S Solbiati G Moschioni B Saggin and DScaccabarozzi ldquoAnalysis of non-linear response of the humanbody to vertical whole-body vibrationrdquo Ergonomics vol 57 no11 pp 1711ndash1723 2014
6 Shock and Vibration
[4] A Nagy ldquoDetermination of E-modulus of young concretewith nondestructive methodrdquo Journal of Materials in CivilEngineering vol 9 no 1 pp 15ndash20 1997
[5] D Dai and Q He ldquoStructure damage localization with ultra-sonic guided waves based on a time-frequency methodrdquo SignalProcessing vol 96 pp 21ndash28 2014
[6] K Marar O Eren and T Celik ldquoRelacion entre la tenacidad aflexion y la energıa de impacto en hormigones de alta resistenciareforzados con fibrasrdquo Materiales de Construccion vol 51 no262 pp 5ndash13 2001
[7] L-Q ChenW-J Zhao and J W Zu ldquoSimulations of transversevibrations of an axially moving string a modified differenceapproachrdquo Applied Mathematics and Computation vol 166 no3 pp 596ndash607 2005
[8] L-Q Chen and H Ding ldquoSteady-state transverse response incoupled planar vibration of axially moving viscoelastic beamsrdquoTransactions of the ASMEmdashJournal of Vibration and Acousticsvol 132 no 1 Article ID 01100919 9 pages 2010
[9] E K Schrader ldquoImpact resistance and test procedure forconcreterdquo Journal of the American Concrete Institute vol 78 no2 pp 141ndash146 1981
[10] A H Hosseinloo F F Yap and L Y Lim ldquoDesign and analysisof shock and random vibration isolation system for a discretemodel of submerged jet impingement cooling systemrdquo Journalof Vibration and Control vol 21 no 3 pp 468ndash482 2015
[11] J WuW Lei QWu YWang and L Ma ldquoTransverse vibrationcharacteristics and stability of a moving membrane with elasticsupportsrdquo Journal of Low Frequency Noise Vibration and ActiveControl vol 33 no 1 pp 65ndash78 2014
[12] M Ghajari Z Sharif-Khodaei M H Aliabadi and A ApicellaldquoIdentification of impact force for smart composite stiffenedpanelsrdquo Smart Materials and Structures vol 22 no 8 ArticleID 085014 2013
[13] R Makowski and R Zimroz ldquoNew techniques of local damagedetection in machinery based on stochastic modelling usingadaptive Schur filterrdquo Applied Acoustics vol 77 pp 130ndash1372014
[14] D W T Wundersitz P B Gastin C Richter S J Robertsonand K J Netto ldquoValidity of a trunk-mounted accelerometer toassess peak accelerations duringwalking jogging and runningrdquoEuropean Journal of Sport Science vol 15 no 5 pp 382ndash3902014
[15] R Klopper M Okuma and J Kruger ldquoA new process formeasuring complete inertia propertiesrdquo MTZ Worldwide vol74 no 3 pp 40ndash44 2013
[16] L-J Dong X-B Li Z-L Zhou G-H Chen and J Ma ldquoThree-dimensional analytical solution of acoustic emission sourcelocation for cuboid monitoring network without pre-measuredwave velocityrdquo Transactions of Nonferrous Metals Society ofChina vol 25 no 1 pp 293ndash302 2015
[17] L Dong X Li and G Xie ldquoAn analytical solution for acousticemission source location for known P wave velocity systemrdquoMathematical Problems in Engineering vol 2014 Article ID290686 6 pages 2014
[18] Q-Y Li L-J Dong X-B Li Z-Q Yin andX-L Liu ldquoEffects ofsonic speed on location accuracy of acoustic emission source inrocksrdquo Transactions of Nonferrous Metals Society of China vol21 no 12 pp 2719ndash2726 2011
[19] L-J Dong and X-B Li ldquoAn efficient closed-form solutionfor acoustic emission source location in threedimensionalstructuresrdquo AIP Advances vol 4 no 2 Article ID 027110 2014
[20] J A Somolinos R Morales A Garcıa and C Moron ldquoPiezo-electric sensors system for impact detectingrdquo Sensor Letters vol11 no 1 pp 128ndash130 2013
[21] J A Somolinos R Morales A Lopez and C Moron ldquoA newself-calibrated procedure for impact detection and location onflat surfacesrdquo Sensors vol 13 no 6 pp 7104ndash7120 2013
Figure 6 Response concrete tile (a) Response of the oscillator (b) Analysis gives harmonics of the sensor response
Sens
or re
spon
se (V
)
minus1
0
0 100 200 300 400 500
1
2
3
4
5
Time (120583s)
(a)
Am
plitu
de (V
)
Harmonic number
05
04
03
02
01
0
0 2 4 6 8 10 12 14 16 18
(b)
Figure 7 Response mortar tile (a) Response of the oscillator (b) Analysis gives harmonics of the sensor response
Thus through a more thorough process the system couldbe used as standard method for the study of vibrations andacoustic insulation against impact noise
Conflict of Interests
The authors declare that there is no conflict of interestsregarding the publication of this paper
References
[1] Espana Codigo Tecnico de la Edificacion Boletın Oficial delEstado 2006
[2] Espana ldquoInstruccion de Hormigon Estructuralrdquo Boletın Oficialdel Estado num 203 2008
[3] M Tarabini S Solbiati G Moschioni B Saggin and DScaccabarozzi ldquoAnalysis of non-linear response of the humanbody to vertical whole-body vibrationrdquo Ergonomics vol 57 no11 pp 1711ndash1723 2014
6 Shock and Vibration
[4] A Nagy ldquoDetermination of E-modulus of young concretewith nondestructive methodrdquo Journal of Materials in CivilEngineering vol 9 no 1 pp 15ndash20 1997
[5] D Dai and Q He ldquoStructure damage localization with ultra-sonic guided waves based on a time-frequency methodrdquo SignalProcessing vol 96 pp 21ndash28 2014
[6] K Marar O Eren and T Celik ldquoRelacion entre la tenacidad aflexion y la energıa de impacto en hormigones de alta resistenciareforzados con fibrasrdquo Materiales de Construccion vol 51 no262 pp 5ndash13 2001
[7] L-Q ChenW-J Zhao and J W Zu ldquoSimulations of transversevibrations of an axially moving string a modified differenceapproachrdquo Applied Mathematics and Computation vol 166 no3 pp 596ndash607 2005
[8] L-Q Chen and H Ding ldquoSteady-state transverse response incoupled planar vibration of axially moving viscoelastic beamsrdquoTransactions of the ASMEmdashJournal of Vibration and Acousticsvol 132 no 1 Article ID 01100919 9 pages 2010
[9] E K Schrader ldquoImpact resistance and test procedure forconcreterdquo Journal of the American Concrete Institute vol 78 no2 pp 141ndash146 1981
[10] A H Hosseinloo F F Yap and L Y Lim ldquoDesign and analysisof shock and random vibration isolation system for a discretemodel of submerged jet impingement cooling systemrdquo Journalof Vibration and Control vol 21 no 3 pp 468ndash482 2015
[11] J WuW Lei QWu YWang and L Ma ldquoTransverse vibrationcharacteristics and stability of a moving membrane with elasticsupportsrdquo Journal of Low Frequency Noise Vibration and ActiveControl vol 33 no 1 pp 65ndash78 2014
[12] M Ghajari Z Sharif-Khodaei M H Aliabadi and A ApicellaldquoIdentification of impact force for smart composite stiffenedpanelsrdquo Smart Materials and Structures vol 22 no 8 ArticleID 085014 2013
[13] R Makowski and R Zimroz ldquoNew techniques of local damagedetection in machinery based on stochastic modelling usingadaptive Schur filterrdquo Applied Acoustics vol 77 pp 130ndash1372014
[14] D W T Wundersitz P B Gastin C Richter S J Robertsonand K J Netto ldquoValidity of a trunk-mounted accelerometer toassess peak accelerations duringwalking jogging and runningrdquoEuropean Journal of Sport Science vol 15 no 5 pp 382ndash3902014
[15] R Klopper M Okuma and J Kruger ldquoA new process formeasuring complete inertia propertiesrdquo MTZ Worldwide vol74 no 3 pp 40ndash44 2013
[16] L-J Dong X-B Li Z-L Zhou G-H Chen and J Ma ldquoThree-dimensional analytical solution of acoustic emission sourcelocation for cuboid monitoring network without pre-measuredwave velocityrdquo Transactions of Nonferrous Metals Society ofChina vol 25 no 1 pp 293ndash302 2015
[17] L Dong X Li and G Xie ldquoAn analytical solution for acousticemission source location for known P wave velocity systemrdquoMathematical Problems in Engineering vol 2014 Article ID290686 6 pages 2014
[18] Q-Y Li L-J Dong X-B Li Z-Q Yin andX-L Liu ldquoEffects ofsonic speed on location accuracy of acoustic emission source inrocksrdquo Transactions of Nonferrous Metals Society of China vol21 no 12 pp 2719ndash2726 2011
[19] L-J Dong and X-B Li ldquoAn efficient closed-form solutionfor acoustic emission source location in threedimensionalstructuresrdquo AIP Advances vol 4 no 2 Article ID 027110 2014
[20] J A Somolinos R Morales A Garcıa and C Moron ldquoPiezo-electric sensors system for impact detectingrdquo Sensor Letters vol11 no 1 pp 128ndash130 2013
[21] J A Somolinos R Morales A Lopez and C Moron ldquoA newself-calibrated procedure for impact detection and location onflat surfacesrdquo Sensors vol 13 no 6 pp 7104ndash7120 2013
[4] A Nagy ldquoDetermination of E-modulus of young concretewith nondestructive methodrdquo Journal of Materials in CivilEngineering vol 9 no 1 pp 15ndash20 1997
[5] D Dai and Q He ldquoStructure damage localization with ultra-sonic guided waves based on a time-frequency methodrdquo SignalProcessing vol 96 pp 21ndash28 2014
[6] K Marar O Eren and T Celik ldquoRelacion entre la tenacidad aflexion y la energıa de impacto en hormigones de alta resistenciareforzados con fibrasrdquo Materiales de Construccion vol 51 no262 pp 5ndash13 2001
[7] L-Q ChenW-J Zhao and J W Zu ldquoSimulations of transversevibrations of an axially moving string a modified differenceapproachrdquo Applied Mathematics and Computation vol 166 no3 pp 596ndash607 2005
[8] L-Q Chen and H Ding ldquoSteady-state transverse response incoupled planar vibration of axially moving viscoelastic beamsrdquoTransactions of the ASMEmdashJournal of Vibration and Acousticsvol 132 no 1 Article ID 01100919 9 pages 2010
[9] E K Schrader ldquoImpact resistance and test procedure forconcreterdquo Journal of the American Concrete Institute vol 78 no2 pp 141ndash146 1981
[10] A H Hosseinloo F F Yap and L Y Lim ldquoDesign and analysisof shock and random vibration isolation system for a discretemodel of submerged jet impingement cooling systemrdquo Journalof Vibration and Control vol 21 no 3 pp 468ndash482 2015
[11] J WuW Lei QWu YWang and L Ma ldquoTransverse vibrationcharacteristics and stability of a moving membrane with elasticsupportsrdquo Journal of Low Frequency Noise Vibration and ActiveControl vol 33 no 1 pp 65ndash78 2014
[12] M Ghajari Z Sharif-Khodaei M H Aliabadi and A ApicellaldquoIdentification of impact force for smart composite stiffenedpanelsrdquo Smart Materials and Structures vol 22 no 8 ArticleID 085014 2013
[13] R Makowski and R Zimroz ldquoNew techniques of local damagedetection in machinery based on stochastic modelling usingadaptive Schur filterrdquo Applied Acoustics vol 77 pp 130ndash1372014
[14] D W T Wundersitz P B Gastin C Richter S J Robertsonand K J Netto ldquoValidity of a trunk-mounted accelerometer toassess peak accelerations duringwalking jogging and runningrdquoEuropean Journal of Sport Science vol 15 no 5 pp 382ndash3902014
[15] R Klopper M Okuma and J Kruger ldquoA new process formeasuring complete inertia propertiesrdquo MTZ Worldwide vol74 no 3 pp 40ndash44 2013
[16] L-J Dong X-B Li Z-L Zhou G-H Chen and J Ma ldquoThree-dimensional analytical solution of acoustic emission sourcelocation for cuboid monitoring network without pre-measuredwave velocityrdquo Transactions of Nonferrous Metals Society ofChina vol 25 no 1 pp 293ndash302 2015
[17] L Dong X Li and G Xie ldquoAn analytical solution for acousticemission source location for known P wave velocity systemrdquoMathematical Problems in Engineering vol 2014 Article ID290686 6 pages 2014
[18] Q-Y Li L-J Dong X-B Li Z-Q Yin andX-L Liu ldquoEffects ofsonic speed on location accuracy of acoustic emission source inrocksrdquo Transactions of Nonferrous Metals Society of China vol21 no 12 pp 2719ndash2726 2011
[19] L-J Dong and X-B Li ldquoAn efficient closed-form solutionfor acoustic emission source location in threedimensionalstructuresrdquo AIP Advances vol 4 no 2 Article ID 027110 2014
[20] J A Somolinos R Morales A Garcıa and C Moron ldquoPiezo-electric sensors system for impact detectingrdquo Sensor Letters vol11 no 1 pp 128ndash130 2013
[21] J A Somolinos R Morales A Lopez and C Moron ldquoA newself-calibrated procedure for impact detection and location onflat surfacesrdquo Sensors vol 13 no 6 pp 7104ndash7120 2013
