1. Università degli studi della BasilicataUniversità degli studi della Basilicata
FACOLTÀFACOLTÀ DIDI INGEGNERIAINGEGNERIA
Corso di Laurea in Ingegneria CivileCorso di Laurea in Ingegneria Civile
Dipartimento di Architettura, Pianificazione ed Infrastrutture di TrasportoDipartimento di Architettura, Pianificazione ed Infrastrutture di Trasporto
CONSTRUCTION OF ROADS, RAILWAYS AND AIRPORTSCONSTRUCTION OF ROADS, RAILWAYS AND AIRPORTS
FinalFinal dissertationdissertation
AntivibrationAntivibration pavements for the protection of historical heritagepavements 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. CuomoCuomo
Dott. Ing. M.Dott. Ing. M. VonaVona
Dott. Ing. R.Dott. Ing. R. DitommasoDitommaso
CANDIDATE:CANDIDATE:
MarioMario MetastasioMetastasio
MatrMatr. 29442. 29442
2. 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
4. ElementaryElementary SchoolSchool “San Giovanni“San Giovanni
Bosco” Via Verdi, Potenza.Bosco” Via Verdi, Potenza.
I)I) ChoiceChoice ofof thethe workingworking sitesite
Structural characteristics:
- The 40’s;
- Reinforced concrete structure;
- Four floors;
- Rectangular scheme.
5. II)II) DesigningDesigning ofof thethe 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
6. MaterialsMaterials
Rubber mat from recycled tyres
ToTo assureassure thethe softeningsoftening ofof thethe
oscillationsoscillations generatedgenerated byby aa
hittinghitting mass on themass on the pavementpavement
Length 1,25 m
Wide 1,00 m
Gauge 0,015 m
Density 730 Kg/m3
∆ Lnw = 21 dB (UNI 140/8)
nudo
ISOLRUBBERISOLRUBBER
Sound-proof
nudo
∆ Lnw = 37,5 dB (UNI
140/6) accoppiato
Compressive strength
2,4 Kg/cm2 deformazione
10% DIN 53421
Tensile strength
4,6 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 Kpa
CC40 = 599 Kpa
CC50 = 599 Kpa
Dynamic stiffness 60 MN/m3
7. 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 bitumen
Riferita al peso degli
inerti
4.80%
Riferita al peso della
miscela
4.58%
Fattore correttivo α 0.98
Massa volumica 2.69 Mg/mc
Costante 2.65
Contenuto minimoPercentages of use
Sabbia 0-4 Aggregato 2-8 Aggregato 10-16 Aggregato 14-22
36 45 19 0
Contenuto minimo
di legante
4.48%
Categoria Bmin 4.4
8. BITUMINOUS EMULSION
To improve and assure the cohesion within
UpperUpper 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 1012
CHARACTERISTICS OFTHE BINDERCHARACTERISTICS 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 the
milled from preexisting pavement
9. III) Laying of the pavement
Size of the pavement
Size of the surface covered in rubber mats
4,55 m
25,00 m
4,00 m
20,00 m
14. 5° stage:
Clening-up of the working area and laying of the rubber mats 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
properties
Length: 16 raws of rubber mats without covering 5,00m
To laying the
bituminous emulsion
15. 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
16. 77°° stage:stage:
Laying and compaction of the binder layer (4cm)
Reopening of the road after
scattering accross the bituminous
emulsion by workers
17. IV) Measurements ante-post operam
DigitalDigital TromometroTromometro
It measures seismic amplification on surface but for this test 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, with
programmable sampling frequency
512 Hz
18. Choice of 4 strike points for the hitting mass
Choice of 4 strike points where generating vibrations ante-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 4
In front of the instrument (10,00m)
19. Generation of the vibrations
Positioning of the hitting mass and generation of the vibrations
Mass: 10 kg Height of fall: 1,10 m
Weight lifting
Positioning
Falling of the mass
20. V) AnalysisAnalysis andand comparisoncomparison ofof measurementsmeasurements anteante--
postpost operamoperam..
Data analysis through
Time 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 laying of the pavement
21. DataData 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 domaindomain analysisanalysis))
Comparison of amplitude of the ascillations in the Time domain:
< ante-post operam;
< N-S, E-W, Z;
< 4 strike points;
< 10 strikes for each point.
22. Example
<Records, ante post operam , of the Time domain analysis 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
23. <Trend of the peaks of the oscillations, Post/Ante operam ,
In Time domain, for strike points 1,2,3 e 4 in direction N-S
24. 2° stage (Frequency domain analysis)
A) Comparison between the amplitudes of the oscillations 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 thethe oscillationsoscillations, first strike, first strike forfor the strikethe strike pointpoint 11
25. <Trend of the peaks of the oscillations, Post/Ante operam ,
in Frequency domain, for strike points 1,2,3,4 in direction N-S.
26. 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
27. CONCLUSIONS
Comparing results , recorded ante-post operam, we have registered:
For each pulsepulse, this configuration reduces the length of the recording in the
configuration post-operam thanks to the increae of the damping factor;
This configuration significantly reduces the smaximum spectral amplitudeamplitude forfor thethe
componentscomponents inin thethe horizontalhorizontal planeplane;
There are increases of the values for the vertical component probably attributable to
problems related to the laying ot the rubber mats.
28. FUTURE DEVELOPMENTS
Improving the laying of the rubber mats:
It would be of considerable interest, not being in literature, realizing a correct protocol for
the laying of the rubber mats inside the road pavement;
It would be desiderable to be able to perform test in situ and in laboratory in order to
control all the variables for the real scale experimentt.
Improving the data analysis:
It would be interesting investigate the causes that generate the amplifications of the
maximum spectral amplitude for the vertical component in the plane;
Could be very interesting investigate a scheme to laying the rubber mats case by case in
order to reduce the amplifications which damage the buildings.
