effect of thickness of gravel base and asphalt pavement on road...

Research ArticleEffect of Thickness of Gravel Base and Asphalt Pavement onRoad Deformation

Dongliang He 12 and Weijun Yang1

1School of Civil Engineering Changsha University of Science and Technology Changsha Hunan 410114 China2School of Civil Engineering Hunan University of City Yiyang Hunan 413000 China

Correspondence should be addressed to Dongliang He hedongliang14126com

Received 14 February 2018 Accepted 28 March 2018 Published 27 June 2018

Academic Editor Rihong Cao

Copyright copy 2018DongliangHe andWeijunYangis is anopen access article distributedunder theCreativeCommonsAttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

is study uses a test section of a highway a study object to explore the effect of thickness of the gravel base and asphalt layer onthe vertical deformation of the road surface e thickness of the asphalt layer and graded gravel base is changed e nonlineardescription equation of the relationship between the thickness (h1) of the asphalt layer and the vertical deformation (d1) isestablished d1 a4(1 bh1

4 ) e thickness of the asphalt pavement is then determined to reduce vertical deformation Numericalcalculation shows that the maximum vertical deformation of the foundation is within 8mm which is less than the 15mmmaximum vertical deformation of the embankment is level meets the design requirements

1 Introduction

Semirigid base asphalt pavement is widely used as the mainstructure of highway pavements [1ndash3] However the wide-spread use of the semirigid base resulted in some problemssuch as the short service life and reduced performance of thepavement which will affect the safety of the highway [4ndash6]eearly destruction of the semirigid base asphalt pavement isaffected by its structure [7ndash9] Temperature and dry shrinkagetend to cause cracks on the semirigid base [10ndash12] Zang et al[13] developed a nondestructive FWD-based evaluation modelto evaluate the semirigid base cracking conditionWu et al [14]simulated the interlayer bonding conditions between thesemirigid base layer and the asphalt layerus rainwater easilyenters from the pavement structure into the grassroots base andsoil is process is called subgrade softening which causesearly damage on the asphalt pavement e particle material(graded gravel) between the asphalt surface layer and thesemirigid base which can be used as the stress dissipation layercan effectively reduce the reflection crack of the semirigidmaterial Graded gravel is characterized by a certain degree ofcompaction of the medium material [15 16] Gravel particlescan produce displacement and mutual dislocation and even-tually achieve vibration compaction under the condition of

traffic load vibration [17ndash19] Volume compression in somegravel materials may cause the pore water pressure to rise dueto dynamic loading which decreases the material strengthKuttah and Arvidsson [20] constructed a trial gravel road andexposed to various levels of the ground water table Chang andPhantachang [21] investigated the effects of gravel content onthe shearing characteristics of gravelly soils e graded gravelbase has good drainage performance us increased porewater pressure and decreased strength are not observed

In this paper the numerical simulation methods are used[22ndash26] which can simulate the construction of the road Atesting section of the Jiangxi Highway China is used as theengineering background to explore the effect of thickness ofthe bituminous pavement and the graded gravel base on thevertical deformation of the road surfacee thicknesses of theasphalt pavement and grading macadam base are changede vertical displacements are then studied

2 Modeling and Parameters

21Modeling A section of a highway is selected for analysis(Figure 1) Given that most of road engineering embank-ments are symmetrical the FLAC3D [27ndash31] is used formodeling analysis in half of the embankments as shown in

HindawiAdvances in Civil EngineeringVolume 2018 Article ID 2076597 7 pageshttpsdoiorg10115520182076597

Figure 2 e total height of the embankment is 8 m andthe slope is 1 15 e width of the embankment is 25mand the width of the upper road is 13m e foundation isequal to the height of the slope which is 10m and theslope to the right is about 1 time the width of the em-bankment which is 25m Table 1 shows the parameters ofthe embankment modeling according to the actual dataprovided by the project For the gravel base the MohrndashCoulomb criterion [32ndash34] is used to describe the stressand strain relation the cohesion is 08MPa and thefriction angle is 24deg

22 Calculation Scheme e model range of the embank-ment is relatively large e focus of the study is the verticaldeformation of the embankment under road load e actionrange is not large because the vehicle load force on the road ofuniformly distributed load is 167 kPa e vertical de-formation of the pavement is largest in the pavement underload erefore the main part of the study is the road surfaceis study selects three kinds of pavement forms with differentthicknesses of the asphalt layer and gravel layer e maincontents of analysis and parts of the embankment model areobservede selection of the pavement and gravel thickness isbased on three criteria (Figure 3) (1) the thickness of theasphalt pavement is 01m and the gravel base thickness is02m which is shortened to 10 to 20 types (2) the thickness ofthe asphalt pavement is 018m and the gravel base thickness is02m which is shortened to 18 to 20 types (3) the thickness ofthe asphalt pavement is 02m and the gravel base thickness is06m which is shortened to 20 to 60 types

Vertical deformation is the vertical deformation of thepavement e distance between the location and em-bankment center is given as follows

his id 1 gp zdis 00 00 00 0his id 12 gp zdis 57 00 00his id 2 gp zdis 20 00 00 0his id 13 gp zdis 64 00 00his id 3 gp zdis 26 00 00 0his id 14 gp zdis 65 00 00his id 4 gp zdis 27 00 00 0his id 15 gp zdis 66 00 00his id 5 gp zdis 28 00 00 0his id 16 gp zdis 67 00 00his id 6 gp zdis 29 00 00 0his id 17 gp zdis 76 00 00his id 7 gp zdis 36 00 00 0his id 18 gp zdis 85 00 00his id 8 gp zdis 47 00 00 0his id 19 gp zdis 86 00 00his id 9 gp zdis 48 00 00 0his id 20 gp zdis 87 00 00his id 10 gp zdis 49 00 00 his id 21 gp zdis 88 00 00his id 11 gp zdis 50 00 00 his id 22 gp zdis 95 00 00

History is divided into two parts namely wheel load andunacted part

His id 1 2 7 12 17 and 22 are the unapplied load partslocated in the middle of the load interval between the twowheels e other part of his id is the part of the wheel loadEach wheel load has two edges and a total of four points in thecenter His id 3 4 5 and 6 are the first group His id 8 9 10and 11 are the second group His id 13 14 15 and 16 are thethird group His id 18 19 20 and 21 are the fourth group

e maximum vertical deformation under load is ana-lyzed in this study e vertical deformation of differentpositions is compared as shown in Figures 4ndash6 e fourcurves in the upper part are the vertical deformation curvesof the embankments in the corresponding four sets of wheelloadse other part shows the vertical deformation curve ofthe embankment with the unapplied load e vertical de-formation of the position under the direct action of vehicleload is the same as that in engineering practice ereforethe vertical deformation value of the four groups of load isanalyzed as follows For the 10 to 20 type the vertical de-formations of his id 3 4 5 and 6 are compared with those ofhis id 13 14 15 and 16 e vertical deformation of the twoplaces was between 6mm and 7mm and the difference wasnot significant Results are consistent with the 18 to 20 type

3 Results and Analysis

31 Influence ofAsphalt Pavement(ickness onEmbankmentTo study the effect of asphalt pavement thickness on the verticaldeformation of the embankment the following data are dividedinto three categories in accordance with the thickness of thegravel layer which is 20 40 and 60 cm respectively

As shown in the calculation in Figure 7 the verticaldeformation of the pavement increases gradually with theincrease of the thickness of the asphalt layer set at 10 15 18and 20 cm when the gravel base thickness is set at 20 cmHowever the slope of the curve decreases erefore theincrease of asphalt thickness decreases the influence of verticaldeformation In addition the relationship between the thick-ness (h1) of the asphalt layer and the vertical deformation (d1)presents nonlinear characteristics e relationship betweenthe two is quantitatively described by the following equationthrough the data fitting method

d1 a4 1minus bh141113872 1113873 (1)

where a4 and b4 are the undetermined coefficientse fitting correlation coefficient of the four groups is

higher than 099 which indicates high correlation evertical deformation of the pavement in the correspondingpoints is small when the thickness of the asphalt layer is10 cm e relative difference of vertical deformation iscomparatively small when the thickness sizes of the asphaltlayer are 15 18 and 20 cm e overall vertical deformationtrend of the road is large in the middle and small on bothsides e vertical deformation of the near embankmentcenter is larger than that of the close shoulder e maxi-mum vertical deformation of the road is at approximately47m from the embankment center

075075075

075075 075

7575 3526

3

2

06

0302 0302

1813 1318

2

06

115 115

Figure 1 Calculation section

2 Advances in Civil Engineering

Previous analysis shows that vertical deformation of thepavement is the smallest of the four asphalt pavement thicknessschemes when the thickness of the gravel layer is certain andthe thickness of the asphalt pavement is 10 cm In additionthe increase of the thickness of the asphalt layer does notsignificantly decrease the vertical deformation of the roadpavement To better understand the influence of asphaltpavement thickness on the vertical deformation of the pave-ment this study analyzes the vertical deformation of theoverall difference of the road surface (Figure 8) When thethickness of the asphalt surface is 10 cm the vertical de-formation of the pavement varies significantly from place to

place although the maximum vertical deformation producedby the pavement is the smallest e asphalt pavement cannoteasily facilitate stress coordination e relative vertical de-formation of the pavement is large and ruts develop easilythereby destroying the asphalt pavement e vertical de-formation of the pavement decreased at asphalt pavement

Table 1 Parameters for the embankment model

Layer Height (m) Elastic modulus Poissonrsquos ratio Constitutive modelAsphalt pavement H1 01 015 018 and 02 1000MPa 03 ElasticGravel base H2 020 040 and 060 mdash mdash MohrndashCoulombEmbankment fill H3 8minusH1minusH2 40MPa 027 ElasticFoundation H410 40MPa 027 Elastic

Asphelt pavement Gravel base

Figure 3 Road surface composition

Figure 4 e vertical deformation for each history point of 10ndash20type


Figure 6 e vertical deformation for each history point of 20ndash60type (a) ickness of the asphalt layer with 10 cm (b) ickness ofthe asphalt layer with 15 cm (c) ickness of the asphalt layer with18 cm (d) ickness of the asphalt layer with 20 cm

13m

8m

10m 10m

25m

12m

50m

Figure 2 Model size in FLAC3D

Advances in Civil Engineering 3

thicknesses of 10 20 and 40 cm but the effect is not sig-nificant When the thickness of the asphalt surface is 18 or20 cm the maximum vertical deformation of the pavement

is slightly increased but the differences of the vertical de-formation of the road are relatively small e asphaltpavement coordinates the stress while the relative verticaldeformation of the pavement decreases Compared with thevertical deformation of the asphalt pavement with thicknessesof 10 18 and 20 cm increasing the thickness of the asphaltpavement can significantly decrease the uneven vertical de-formation of the pavement

32 Influence ofGravel Base(ickness onEmbankment Whenthe thickness of the asphalt pavement is 10 cm (Table 2)vertical deformation decreases on both sides of the road anda trend of decrease after the first increase in the middle of theroad is shown as the gravel base thicknesses of 20 40 and60 cm gradually increased e vertical deformation of thepavement is smallest when the thickness of the gravel baseis 60 cm that is when the gravel base is the thickest eoverall vertical deformation trend of the road is large andsmall on both sides e vertical deformation of the nearembankment center is larger than that of the closeshoulderemaximum vertical deformation of the road is

10 12 14 16 18 20665

670

675

680

685

690

695

700

Asphalt pavement thickness (cm)

Model BoxLucas1Equation y = alowast(1 ndash b)Reducedchi-square 309519E ndash 5

Adj R-square 099838Value Standard error

B a 6985 000406B b 0731 000179

Vert

ical

def

orm

atio

n (m

m)

(a)

10 12 14 16 18 20Asphalt pavement thickness (cm)

690

695

700

705

710

715

720

725

730

Model BoxLucas1Equation y = alowast(1 ndash b^)Reducedchi-square 207099E ndash 4


C a 7280 001074C b 0740 000403

Vert

ical

def

orm

atio

n (m

m)

(b)


665

670

675

680

685

690

695

700

705

710



D a 7074 001066D b 0751 000358

Vert

ical

def

orm

atio

n (m

m)

(c)


565

570

575

580

585

590

595

Model BoxLucas1M

Equation y = alowast(1 ndash b^x)Reducedchi-square 157053E ndash 4


E a 5936 00091E b 07302 000482

Vert

ical

def

orm

atio

n (m

m)

(d)

Figure 7 Vertical deformation of the road for 20 cm thickness of the gravel base

0

12

3

45

67

8

0 2 4 6 8 10Horizontal distance (m)

10ndash20

10ndash40

18ndash20

20ndash60

Vert

ical

disp

lace

men

t (m

m)

Figure 8 Relationship between the asphalt layer and pavementwith uneven vertical deformation


at the direct part of the wheel load approximately 47mfrom the embankment center

When the thickness of the asphalt pavement is 15 cm(Table 3) the vertical deformation of the sides andthe middle section decreases as the gravel base thicknesses of

20 40 and 60 cm gradually increase which is different from10 cm thicknesse vertical deformation of the pavement ineach group is smallest when the gravel base thickness is60 cm that is when the gravel base is the thickest

When the thickness of the asphalt pavement is 18 cm(Table 4) the vertical deformations on both sides of the roadand of the middle two positions show a decreasing trend asthe gravel base thicknesses of 20 40 and 60 cm graduallyincrease

When the thickness of the asphalt pavement is 20 cm(Table 5 and Figure 9) the vertical deformation caused by20 40 and 60 cm gravel base thicknesses is the samePrevious analysis shows that the increase of gravel basethickness can reduce the vertical deformation of the roadwhen the thickness of the asphalt surface is certainerefore the method of increasing the gravel basethickness can be used to reduce the vertical deformation ofthe road

4 Conclusions

(1) e vertical deformation of the pavement increasesas the thickness of the asphalt layer increasesgradually from 10 cm to 15 18 and 20 cm but theslope of the curve gradually decreases

(2) Asphalt pavement cannot easily facilitate stress co-ordination when the relative vertical deformation

Table 2 Vertical deformation for the asphalt pavement thickness of 10 cm

ickness of the gravel base (cm) First class Second class ird class Fourth class20 6679 6921 6673 568340 6591 6944 6691 560960 6437 6700 6522 5502







5000

5500

6000

6500

7000

7500

First class Second class ird class Fourth class

Gravel thickness 20cmGravel thickness 40cmGravel thickness 60cm

Figure 9 Vertical deformation for the asphalt pavement thicknessof 20 cm


of the pavement is large Ruts may develop easilythereby destroying the asphalt pavement Comparedwith the vertical deformation of the asphalt pave-ment with thicknesses of 10 cm 18 cm and 20 cmincreasing the thickness of the asphalt pavement cansignificantly reduce the uneven vertical deformationof the pavement

(3) When the thickness of the asphalt pavement is certainthe vertical deformation of the pavement decreaseswith the increase of the thickness of the gravel basefrom 20 cm 40 cm and 60 cm e vertical de-formation of the pavement in each group is smallestwhen the thickness of the gravel base is 60 cm

Conflicts of Interest

e authors declare no conflicts of interest

References

[1] M Ameri A Mansourian M H Khavas M R M Aliha andM R Ayatollahi ldquoCracked asphalt pavement under trafficloadingndasha 3D finite element analysisrdquo Engineering FractureMechanics vol 78 no 8 pp 1817ndash1826 2011

[2] B Huang G Li D Vukosavljevic X Shu and B K EganldquoLaboratory investigation of mixing hot-mix asphalt withrecycled asphalt pavementrdquo Transportation Research Recordvol 1929 pp 37ndash45 2005

[3] M A Mull K Stuart and A Yehia ldquoFracture resistancecharacterization of chemically modified crumb rubber asphaltpavementrdquo Journal of Materials Science vol 37 no 3pp 557ndash566 2002

[4] D R Roman ldquoA surrogate-assisted genetic algorithm for theselection and design of highway safety and travel time im-provement projectrdquo Safety Science vol 108 pp 305ndash315 2018

[5] S Jung K Wang C Oh and J Chang ldquoDevelopment ofhighway safety policies by discriminating freeway curvealignment featuresrdquo KSCE Journal of Civil Engineeringpp 1ndash9 2017

[6] J Y Rao T Xie and Y M Liu ldquoFuzzy evaluation model forin-service karst highway tunnel structural safetyrdquo KSCEJournal of Civil Engineering vol 20 no 4 pp 1242ndash12492016

[7] Q Liu and D Cao ldquoResearch on material composition andperformance of porous asphalt pavementrdquo Journal of Mate-rials in Civil Engineering vol 21 no 4 pp 135ndash140 2009

[8] K L Roja A Padmarekha and J M Krishnan ldquoInfluence ofwarm mix additive and loading rate on rutting of warm mixasphalt pavementrdquo International Journal of Pavement Engi-neering p 16 2017

[9] E V Dave and B Behnia ldquoCohesive zone fracture modellingof asphalt pavements with applications to design of high-performance asphalt overlaysrdquo International Journal ofPavement Engineering vol 19 no 3 pp 1ndash19 2017

[10] M Minhoto J Pais P Pereira and L Picado-Santos ldquoPre-dicting asphalt pavement temperature with a three-dimensional finite element methodrdquo Transportation Re-search Record Journal of the Transportation Research Boardvol 1919 pp 96ndash110 2005

[11] J Qin and L J Sun ldquoStudy on asphalt pavement temperaturefield distribution patternrdquo Journal of Highway and Trans-portation Research and Development vol 31 no 4 2006

[12] S M Bazlamit and F Reza ldquoChanges in asphalt pavementfriction components and adjustment of skid number fortemperaturerdquo Journal of Transportation Engineering vol 131no 6 pp 470ndash476 2005

[13] G Zang L Sun Z Chen and L Li ldquoA nondestructiveevaluation method for semi-rigid base cracking condition ofasphalt pavementrdquo Construction and Building Materialsvol 162 pp 892ndash897 2018

[14] S Wu H Chen J Zhang and Z Zhang ldquoEffects of interlayerbonding conditions between semi-rigid base layer and asphaltlayer onmechanical responses of asphalt pavement structurerdquoInternational Journal of Pavement Research and Technologyvol 10 no 3 pp 274ndash281 2017

[15] J Shaw and G Gorrell ldquoSubglacially formed dunes withbimodal and graded gravel in the Trenton Drumlin FieldOntariordquo Geographie Physique et Quaternaire vol 45 no 1p 21 1991

[16] B Yu M Zhang and T Li ldquoAnalysis of the micro bondinggraded gravel asphalt pavement structurerdquo Shenyang JianzhuDaxue Xuebao vol 29 pp 852ndash860 2013

[17] J E Pizzuto ldquoe morphology of graded gravel riversa network perspectiverdquo Geomorphology vol 5 no 3ndash5pp 457ndash474 1992

[18] K G Heays H Friedrich B W Melville and R NokesldquoQuantifying the dynamic evolution of graded gravel bedsusing particle tracking velocimetryrdquo Journal of HydraulicEngineering vol 140 p 04014027 2014

[19] D P Pham Q Su W H Zhao and A T Vu ldquoDynamiccharacteristics and mud pumping mechanism of gradedgravel under cyclic loadingrdquo Electronic Journal of Geo-technical Engineering vol 20 pp 1391ndash1406 2015

[20] D Kuttah and H Arvidsson ldquoEffect of groundwater tablerising on the performance of a Swedish-designed gravel roadrdquoTransportation Geotechnics vol 11 pp 82ndash96 2017

[21] W-J Chang and T Phantachang ldquoEffects of gravel content onshear resistance of gravelly soilsrdquo Engineering Geologyvol 207 pp 78ndash90 2016

[22] H Lin W Xiong and Q Yan ldquoree-dimensional effect oftensile strength in the standard Brazilian test consideringcontact lengthrdquo Geotechnical Testing Journal vol 39 no 1pp 137ndash143 2016

[23] M Jiang C Sun A Rodriguezdono N Zhang and J ShaoldquoInfluence of time-dependence on failure of echelon rockjoints through a novel DEM modelrdquo European Journal ofEnvironmental and Civil Engineering vol 19 no 1 pp s108ndashs118 2015

[24] I Stefanou and J Sulem ldquoContinuum modeling of discon-tinuous rock structuresrdquo European Journal of Environmentaland Civil Engineering vol 14 no 8-9 pp 1199ndash1217 2010

[25] R Cao P Cao H Lin and X Fan ldquoExperimental and nu-merical study of the failure process and energy mechanisms ofrock-like materials containing cross un-persistent joints un-der uniaxial compressionrdquo PLoS One vol 12 no 12 ArticleID e0188646 2017

[26] A T Ozer O Akay and G A Fox ldquoA new method forremediation of sandy slopes susceptible to seepage flow usingEPS-block geofoamrdquo Geotextiles and Geomembranes vol 42no 2 pp 166ndash180 2014

[27] H Lin and J Chen ldquoBack analysis method of homogeneousslope at critical staterdquo KSCE Journal of Civil Engineeringvol 21 no 3 pp 670ndash675 2017

[28] D P Zhu Y D Lin and E Yan ldquoree-dimensional nu-merical analysis on excavation and support of deep pit nearthe subway tunnel by computer simulation techniquerdquo


Journal of (eoretical and Applied Information Technologyvol 45 pp 621ndash626 2012

[29] L Z Wu and R Q Huang ldquoCalculation of the internal forcesand numerical simulation of the anchor frame beamstrengthening expansive soil sloperdquo Geotechnical and Geo-logical Engineering vol 26 no 5 pp 493ndash502 2008

[30] M Cai P Kaiser H Morioka et al ldquoFLACPFC couplednumerical simulation of AE in large-scale underground ex-cavationsrdquo International Journal of Rock Mechanics andMining Sciences vol 44 no 4 pp 550ndash564 2007

[31] M C He J L Feng and X M Sun ldquoStability evaluation andoptimal excavated design of rock slope at Antaibao open pitcoal mine Chinardquo International Journal of Rock Mechanicsand Mining Sciences vol 45 no 3 pp 289ndash302 2008

[32] Y Zhao Y WangWWangWWan and J Tang ldquoModelingof non-linear rheological behavior of hard rock using triaxialrheological experimentrdquo International Journal of Rock Me-chanics and Mining Sciences vol 93 pp 66ndash75 2017

[33] A Amavasai J P Gras N Sivasithamparam M Karstunenand J Dijkstra ldquoTowards consistent numerical analyses ofembankments on soft soilsrdquo European Journal of Environ-mental and Civil Engineering pp 1ndash19 2017

[34] J F Zou S S Li Y Xu H C Dan and L H Zhao ldquoe-oretical solutions for a circular opening in an elasticndashbrittlendashplastic rock mass incorporating the out-of-plane stressand seepage forcerdquo KSCE Journal of Civil Engineering vol 20no 2 pp 687ndash701 2016


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Submit your manuscripts atwwwhindawicom

Figure 2 e total height of the embankment is 8 m andthe slope is 1 15 e width of the embankment is 25mand the width of the upper road is 13m e foundation isequal to the height of the slope which is 10m and theslope to the right is about 1 time the width of the em-bankment which is 25m Table 1 shows the parameters ofthe embankment modeling according to the actual dataprovided by the project For the gravel base the MohrndashCoulomb criterion [32ndash34] is used to describe the stressand strain relation the cohesion is 08MPa and thefriction angle is 24deg

22 Calculation Scheme e model range of the embank-ment is relatively large e focus of the study is the verticaldeformation of the embankment under road load e actionrange is not large because the vehicle load force on the road ofuniformly distributed load is 167 kPa e vertical de-formation of the pavement is largest in the pavement underload erefore the main part of the study is the road surfaceis study selects three kinds of pavement forms with differentthicknesses of the asphalt layer and gravel layer e maincontents of analysis and parts of the embankment model areobservede selection of the pavement and gravel thickness isbased on three criteria (Figure 3) (1) the thickness of theasphalt pavement is 01m and the gravel base thickness is02m which is shortened to 10 to 20 types (2) the thickness ofthe asphalt pavement is 018m and the gravel base thickness is02m which is shortened to 18 to 20 types (3) the thickness ofthe asphalt pavement is 02m and the gravel base thickness is06m which is shortened to 20 to 60 types

Vertical deformation is the vertical deformation of thepavement e distance between the location and em-bankment center is given as follows

his id 1 gp zdis 00 00 00 0his id 12 gp zdis 57 00 00his id 2 gp zdis 20 00 00 0his id 13 gp zdis 64 00 00his id 3 gp zdis 26 00 00 0his id 14 gp zdis 65 00 00his id 4 gp zdis 27 00 00 0his id 15 gp zdis 66 00 00his id 5 gp zdis 28 00 00 0his id 16 gp zdis 67 00 00his id 6 gp zdis 29 00 00 0his id 17 gp zdis 76 00 00his id 7 gp zdis 36 00 00 0his id 18 gp zdis 85 00 00his id 8 gp zdis 47 00 00 0his id 19 gp zdis 86 00 00his id 9 gp zdis 48 00 00 0his id 20 gp zdis 87 00 00his id 10 gp zdis 49 00 00 his id 21 gp zdis 88 00 00his id 11 gp zdis 50 00 00 his id 22 gp zdis 95 00 00

History is divided into two parts namely wheel load andunacted part

His id 1 2 7 12 17 and 22 are the unapplied load partslocated in the middle of the load interval between the twowheels e other part of his id is the part of the wheel loadEach wheel load has two edges and a total of four points in thecenter His id 3 4 5 and 6 are the first group His id 8 9 10and 11 are the second group His id 13 14 15 and 16 are thethird group His id 18 19 20 and 21 are the fourth group

e maximum vertical deformation under load is ana-lyzed in this study e vertical deformation of differentpositions is compared as shown in Figures 4ndash6 e fourcurves in the upper part are the vertical deformation curvesof the embankments in the corresponding four sets of wheelloadse other part shows the vertical deformation curve ofthe embankment with the unapplied load e vertical de-formation of the position under the direct action of vehicleload is the same as that in engineering practice ereforethe vertical deformation value of the four groups of load isanalyzed as follows For the 10 to 20 type the vertical de-formations of his id 3 4 5 and 6 are compared with those ofhis id 13 14 15 and 16 e vertical deformation of the twoplaces was between 6mm and 7mm and the difference wasnot significant Results are consistent with the 18 to 20 type

3 Results and Analysis

31 Influence ofAsphalt Pavement(ickness onEmbankmentTo study the effect of asphalt pavement thickness on the verticaldeformation of the embankment the following data are dividedinto three categories in accordance with the thickness of thegravel layer which is 20 40 and 60 cm respectively

As shown in the calculation in Figure 7 the verticaldeformation of the pavement increases gradually with theincrease of the thickness of the asphalt layer set at 10 15 18and 20 cm when the gravel base thickness is set at 20 cmHowever the slope of the curve decreases erefore theincrease of asphalt thickness decreases the influence of verticaldeformation In addition the relationship between the thick-ness (h1) of the asphalt layer and the vertical deformation (d1)presents nonlinear characteristics e relationship betweenthe two is quantitatively described by the following equationthrough the data fitting method

d1 a4 1minus bh141113872 1113873 (1)

where a4 and b4 are the undetermined coefficientse fitting correlation coefficient of the four groups is

higher than 099 which indicates high correlation evertical deformation of the pavement in the correspondingpoints is small when the thickness of the asphalt layer is10 cm e relative difference of vertical deformation iscomparatively small when the thickness sizes of the asphaltlayer are 15 18 and 20 cm e overall vertical deformationtrend of the road is large in the middle and small on bothsides e vertical deformation of the near embankmentcenter is larger than that of the close shoulder e maxi-mum vertical deformation of the road is at approximately47m from the embankment center

075075075

075075 075

7575 3526

3

2

06

0302 0302

1813 1318

2

06

115 115

Figure 1 Calculation section











13m

8m

10m 10m

25m

12m

50m






10 12 14 16 18 20665

670

675

680

685

690

695

700




B a 6985 000406B b 0731 000179

Vert

ical

def

orm

atio

n (m

m)

(a)


690

695

700

705

710

715

720

725

730



C a 7280 001074C b 0740 000403

Vert

ical

def

orm

atio

n (m

m)

(b)


665

670

675

680

685

690

695

700

705

710



D a 7074 001066D b 0751 000358

Vert

ical

def

orm

atio

n (m

m)

(c)


565

570

575

580

585

590

595

Model BoxLucas1M



E a 5936 00091E b 07302 000482

Vert

ical

def

orm

atio

n (m

m)

(d)


0

12

3

45

67

8


10ndash20

10ndash40

18ndash20

20ndash60

Vert

ical

disp

lace

men

t (m

m)








4 Conclusions











5000

5500

6000

6500

7000

7500









References








































RoboticsJournal of




VLSI Design



Shock and Vibration







Journal of



Volume 2018



Volume 2018


Journal of




SensorsJournal of



RotatingMachinery





Propagation






Hindawi


Advances in

Multimedia











13m

8m

10m 10m

25m

12m

50m






10 12 14 16 18 20665

670

675

680

685

690

695

700




B a 6985 000406B b 0731 000179

Vert

ical

def

orm

atio

n (m

m)

(a)


690

695

700

705

710

715

720

725

730



C a 7280 001074C b 0740 000403

Vert

ical

def

orm

atio

n (m

m)

(b)


665

670

675

680

685

690

695

700

705

710



D a 7074 001066D b 0751 000358

Vert

ical

def

orm

atio

n (m

m)

(c)


565

570

575

580

585

590

595

Model BoxLucas1M



E a 5936 00091E b 07302 000482

Vert

ical

def

orm

atio

n (m

m)

(d)


0

12

3

45

67

8


10ndash20

10ndash40

18ndash20

20ndash60

Vert

ical

disp

lace

men

t (m

m)








4 Conclusions











5000

5500

6000

6500

7000

7500









References








































RoboticsJournal of




VLSI Design



Shock and Vibration







Journal of



Volume 2018



Volume 2018


Journal of




SensorsJournal of



RotatingMachinery





Propagation






Hindawi


Advances in

Multimedia





10 12 14 16 18 20665

670

675

680

685

690

695

700




B a 6985 000406B b 0731 000179

Vert

ical

def

orm

atio

n (m

m)

(a)


690

695

700

705

710

715

720

725

730



C a 7280 001074C b 0740 000403

Vert

ical

def

orm

atio

n (m

m)

(b)


665

670

675

680

685

690

695

700

705

710



D a 7074 001066D b 0751 000358

Vert

ical

def

orm

atio

n (m

m)

(c)


565

570

575

580

585

590

595

Model BoxLucas1M



E a 5936 00091E b 07302 000482

Vert

ical

def

orm

atio

n (m

m)

(d)


0

12

3

45

67

8


10ndash20

10ndash40

18ndash20

20ndash60

Vert

ical

disp

lace

men

t (m

m)








4 Conclusions











5000

5500

6000

6500

7000

7500









References








































RoboticsJournal of




VLSI Design



Shock and Vibration







Journal of



Volume 2018



Volume 2018


Journal of




SensorsJournal of



RotatingMachinery





Propagation






Hindawi


Advances in

Multimedia







4 Conclusions











5000

5500

6000

6500

7000

7500









References








































RoboticsJournal of




VLSI Design



Shock and Vibration







Journal of



Volume 2018



Volume 2018


Journal of




SensorsJournal of



RotatingMachinery





Propagation






Hindawi


Advances in

Multimedia






References








































RoboticsJournal of




VLSI Design



Shock and Vibration







Journal of



Volume 2018



Volume 2018


Journal of




SensorsJournal of



RotatingMachinery





Propagation






Hindawi


Advances in

Multimedia












RoboticsJournal of




VLSI Design



Shock and Vibration







Journal of



Volume 2018



Volume 2018


Journal of




SensorsJournal of



RotatingMachinery





Propagation






Hindawi


Advances in

Multimedia


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