Università degli studi della BasilicataUniversità degli studi della Basilicata

FACOLTÀ FACOLTÀ DIDI INGEGNERIAINGEGNERIA

Corso di Laurea in Ingegneria CivileCorso di Laurea in Ingegneria CivileDipartimento di Architettura, Pianificazione ed Inf rastrutture di TrasportoDipartimento di Architettura, Pianificazione ed Inf rastrutture di Trasporto

CONSTRUCTION OF ROADS, RAILWAYS AND AIRPORTSCONSTRUCTION OF ROADS, RAILWAYS AND AIRPORTS

FinalFinal dissertationdissertation

AntivibrationAntivibration pavements for the protection of histor ical heritage pavements for the protection of historical heritage and public buildingsand public buildings

SUPERVISOR: SUPERVISOR: Ch.moCh.mo Prof. Ing. M. Prof. Ing. M. AgostinacchioAgostinacchio

ASSISTANT SUPERVISORS:ASSISTANT SUPERVISORS:Dott. Ing. G. Dott. Ing. G. CuomoCuomoDott. Ing. M. Dott. Ing. M. VonaVonaDott. Ing. R. Dott. Ing. R. DitommasoDitommaso

CANDIDATE: CANDIDATE: Mario Mario MetastasioMetastasioMatrMatr. 29442. 29442

TargetTarget

� Realization of an antivibration hot-mix pavement to assure :

1) Softening of mechanics waves produced by vehicles

public

historical

nearby buildings such as :

2) Environmental safety ,using:

cultural

generating

RubberRubber matsmats fromfrom recycledrecycled tyrestyres

“noise”

exterior and structural damages

�� The work The work hashas beenbeen developeddeveloped in 5 in 5 stagesstages: :

I)I) ChoiceChoice ofof thethe workingworking sitesite;;

II)II) DesigningDesigning ofof thethe pavementpavement;;

AnalysisAnalysis

III)III) LayingLaying ofof thethe pavementpavement;;

IV)IV) MeasurementsMeasurements anteante--postpost operamoperam;;

V)V) AnalysisAnalysis andand comparisoncomparison ofof measurementsmeasurements anteante--postpost operamoperam..

ElementaryElementary SchoolSchool “San Giovanni “San Giovanni Bosco” Via Verdi, Potenza.Bosco” Via Verdi, Potenza.

I) I) ChoiceChoice ofof the the workingworking site site

Structural characteristics:

- The 40’s;

- Reinforced concrete structure;

- Four floors;

- Rectangular scheme.

II) II) DesigningDesigning ofof the the pavementpavement

� Total gauge of the antivibration pavement: 8,5 cm

BinderBinder,,In hot -mix (4,0cm)

� Overlapping of three layers:

In hot -mix (4,0cm)

Base, Base, in granular mixture (3,0cm)

AntivibrantAntivibrant, in rubber mats (1,5cm)

� Preexisting foundations layer

MaterialsMaterials

� Rubber mat from recycled tyresToTo assureassure the the softeningsoftening ofof the the

oscillationsoscillations generatedgenerated byby a a hittinghitting mass on the mass on the pavementpavement

Length 1,25 mWide 1,00 mGauge 0,015 mDensity 730 Kg/m3

∆ Lnw = 21 dB (UNI 140/8) nudo

ISOLRUBBERISOLRUBBER

Sound-proofnudo ∆ Lnw = 37,5 dB (UNI 140/6) accoppiato

Compressive strength2,4 Kg/cm2 deformazione 10% DIN 53421

Tensile strength4,6 Kg/cm2 DIN EN ISO 1798

Elongation at break 40% DIN EN ISO 1798

Elasticity in compression 27,5 Kg/cm2

Determination of the stress-strain characteristics in the

compression

CC25 = 599 KpaCC40 = 599 KpaCC50 = 599 Kpa

Dynamic stiffness 60 MN/m3

HOTHOT--MIXMIX

� To realize the upper layer “BINDERONE”“BINDERONE”

Project curve

Apertura Vaglia (mm)

40 31,5 22,4 16 11,2 8 5,6 4 2 1 0,1

Curva Progetto 100 100 100 99,47 84,28 80,17 55,26 47,11 32,26 21,98 6,01

Fuso di riferimento Dmax = 16 mm secondo UNI Eni 13108

Apertura setacci (mm) 22,4 16 2 0,063

Passante percentuale 100 100 50 12

Passante percentuale 100 90 10 0

Percentages of use

Percentuage of bitumenRiferita al peso degli

inerti4.80%

Riferita al peso della miscela

4.58%

Fattore correttivo α 0.98

Massa volumica 2.69 Mg/mc

Costante 2.65

Contenuto minimo Percentages of use

Sabbia 0-4 Aggregato 2-8 Aggregato 10-16 Aggregato 14-2236 45 19 0

Contenuto minimo di legante

4.48%

Categoria Bmin 4.4

BITUMINOUS EMULSION

� To improve and assure the cohesion within

Upper Upper layerlayer

LowerLower layerlayer

ANIONIC BITUMINOUS EMULSIONANIONIC BITUMINOUS EMULSION

Carattesristiche Metodo di prova Valori

Contenuto di acqua [%] NF-T 66-023 43<47

Contenuto di fluss. [%] C.N.R. n 100 1<3

Viscosità E a 20 C NF-T 66-020 5<8

Omogeneità a 630 [μ] NF-T 66-016 <0.2

GRANULAR MIXTURE Omogeneità a 160 [µ] NF-T 66-016 <0.25

Sedimentazione a 5 gg. C.N.R. n 124 ≤5

Indice di rottura NF-T 66-017 <98

Carica delle particelle NF-T 66-021 positiva

pH (grado di acidità) procedura interna 10\12

CHARACTERISTICS OFTHE BINDER CHARACTERISTICS OFTHE BINDER Penetrazione a 25 C

[dmm]EN 1426 70<220

Viscosità a 160 C [Pa.s-

1]EN 2595 0.060<0.160

Punto di rammollimento [ C]

EN 1427 35<46

Punto di rottura (Fraass) [ C]

EN 12593 <-10

GRANULAR MIXTURE

� For the lower layer has been used themilled from preexisting pavement

III) Laying of the pavement

� Size of the pavement

� Size of the surface covered in rubber mats

4,55 m

25,00 m4,00 m

20,00 m

LayingLaying stagesstages

� Laying pavement in 7 stages:

1° stage:

� Management of

WorkersWorkers

MachineriesMachineries

2° stage:

� Delimitation of the working area Alternate Alternate closureclosure ofof the the laneslanes

� Delimitation of the area for scarification

3° stage:

� Scarification of the preexisting pavement

Depth: 8,5cm Direction: Via Verdi-Viale Marconi

4° stage:

� Collection and storage of the milled layer on a truck

5° stage:

� Clening-up of the working area and laying of the rubber m ats from recycled tyres

� Size of the area for the rubber mats

4,00m x 20,00m

� Size of the scarificated area

4,55m x 25,00m4,55m x 25,00m

Wide: 4 raws of rubber mats without covering 0,55m To assure softening propertiesLength: 16 raws of rubber mats without covering 5,0 0m

To laying the bituminous emulsion

6° stage:

� Laying of the base layer made of granular mixture

Gauge: 3 cm

Reuse of the milled layer

� sprinkled by workers

� compacted by a roller

� deposited by a digger

77°° stage:stage:

� Laying and compaction of the binder layer (4cm)

� Reopening of the road afterscattering accross the bituminousemulsion by workers

IV) Measurements ante-post operam

DigitalDigital TromometroTromometro

� It measures seismic amplification on surface but for this te st we have used it to measure

the vibrations on a building

Barycenter long side

of the building

North

� Location of the instrument

of the building

Exit of the School

Three electrodynamic sensors (velocimeters N-S, E-W, Z)

GPS system

Acquisition of noise data, amplified and digitized at 24 bit, withprogrammable sampling frequency

512 Hz

Choice of 4 strike points for the hitting mass� Choice of 4 strike points where generating vibrations ant e-post operam

Point 1

Point 2Point 3

In front of the instrument (5,50m)

To the right of the point 1 (5,00m)

To the left of the Point 1 (5,00m)

Point 4In front of the instrument (10,00m)

Generation of the vibrations

� Positioning of the hitting mass and generation of the vibrat ions

Mass: 10 kg Height of fall: 1,10 m

Weight lifting

Positioning

Falling of the mass

V) AnalysisAnalysis and and comparisoncomparison ofof measurementsmeasurements anteante--post post operamoperam ..

� Data analysis throughTime domain

Frequency domain

TIME DOMAIN ANALYSISTIME DOMAIN ANALYSIS

� peak values of the oscillations ante-post operam

FREQUENCY DOMAIN ANALYSISFREQUENCY DOMAIN ANALYSIS

� Spectral parameters Maximum value for Fourier’s spectrum recorded on velocimeter tracks

Fourier’s spectruma area

This analysis has been conducted before and after the layi ng of the pavement

Data Data analysisanalysis usingusing ““MatlabMatlab” (” (MathworksMathworks) software) software

Management of recorded data using

the database of “Grilla” software

Codified file in

file ASCII

� Matlab data analysis in two stages:

11°° stage (stage (TimeTime domain domain analysisanalysis))

Comparison of amplitude of the ascillations in the Time doma in:

< ante-post operam;

< N-S, E-W, Z;

< 4 strike points;

< 10 strikes for each point.

Example

<Records, ante post operam , of the Time domain ana lysis for the first strike,

in strike point 2, in the three directions W-E,N-S e Z.

DAMPING FACTOR(ξ)

Stikes

W-E N-S Z

Ante Post Ante Post Ante Post

1 2,21 4,98 2,42 3,24 4,99 4,48

2 1,87 4,45 3,49 4,62 2,58 3,812 1,87 4,45 3,49 4,62 2,58 3,81

3 1,81 4,12 0,11 3,40 5,74 2,83

4 2,65 3,32 2,12 3,68 4,98 6,14

5 2,60 3,63 2,68 3,45 5,69 5,66

6 2,17 4,16 3,24 3,02 5,78 3,60

7 1,90 5,97 3,27 4,43 4,37 2,46

8 1,92 4,30 2,42 4,28 4,35 5,10

9 1,92 2,46 2,41 3,33 4,77 2,97

10 2,07 4,03 2,82 5,06 5,32 3,50

Mean 2,11 4,14 2,50 3,85 4,86 4,06

STD 0,30 0,94 0,95 0,69 0,96 1,25

<Trend of the peaks of the oscillations, Post/Ante operam ,

In Time domain, for strike points 1,2,3 e 4 in dire ction N-S

2° stage (Frequency domain analysis)

A) Comparison between the amplitudes of the oscillation s in Frequency domain:

Example:

< ante-post operam;

< W-E,N-S,Z;

< 4 strike points;

< 10 strikes for each point.

<Fourier’s <Fourier’s spectraspectra forfor the the oscillationsoscillations, first strike , first strike forfor the strike the strike pointpoint 1 1

<Trend of the peaks of the oscillations, Post/Ante operam ,

in Frequency domain, for strike points 1,2,3,4 in d irection N-S.

B) Comparison between Fourier’s spectra areas:< ante-post operam;

< W-E,N-S,Z;

< 4 strike points;

< 10 strikes for each point.

Example:

<Trend of Fourier’s spectra areas, Post/Ante operam , for strike points 1,2,3,4 in direction N-S

CONCLUSIONS

Comparing results , recorded ante-post operam, we have regi stered:

� For each pulsepulse , this configuration reduces the length of the recording in t heconfiguration post-operam thanks to the increae of the damp ing factor ;

� This configuration significantly reduces the smaximum spectral amplitudeamplitude forfor thethecomponentscomponents inin thethe horizontalhorizontal planeplane ;

� There are increases of the values for the vertical component probably attributable toproblems related to the laying ot the rubber mats.

FUTURE DEVELOPMENTS

Improving the laying of the rubber mats:

�It would be of considerable interest, not being in literatur e, realizing a correct protocol forthe laying of the rubber mats inside the road pavement;

�It would be desiderable to be able to perform test in situ and i n laboratory in order tocontrol all the variables for the real scale experimentt.

Improving the data analysis:

�It would be interesting investigate the causes that generat e the amplifications of themaximum spectral amplitude for the vertical component in th e plane;

�Could be very interesting investigate a scheme to laying the rubber mats case by case inorder to reduce the amplifications which damage the buildin gs.