CN104878669A - Method for deciding pavement laying scheme - Google Patents

Abstract

The invention relates to a method for deciding a pavement laying scheme, which comprises the steps of estimating indexes corresponding to related pavement characteristics, economic characteristics and emission characteristics in each pavement laying scheme; conducting the standardization treatment on estimated indexes according to maximal or minimal attributes to obtain standardized index values corresponding to the indexes; setting index weighting coefficients corresponding to all the indexes, and conducting the setting calculation for all the index weighting coefficients and all the standardized index values to obtain integrated assessment values corresponding to all pavement laying schemes respectively; and selecting one pavement laying scheme of the highest integrated assessment value as a finally adopted scheme. According to the invention, a variety of factors are taken into consideration on a comprehensive decision for the pavement design, and the performance of the life cycle in the pavement characteristics is taken into consideration. In this way, the pavement design is better in cost performance. Meanwhile, a more scientific, more economic and more environment-friendly pavement design scheme can be made. At the same time, required data can be acquired simply, objectively and quantitatively during the measuring and calculating process.

Description

A kind of decision-making technique of road surfacing scheme

Technical field

The present invention relates to road surfacing, particularly relate to a kind of decision-making technique of road surfacing scheme.

Background technology

Traditional road design only considers the factors such as meeting of road surface supporting capacity, functional requirement and construction cost accounting when determining design scheme, by the checking of long-term road occupation, the road surfacing scheme designed under this design concept, can be there is such problem in its road, maintenance expense often will exceed the expense of primary construction in the later stage uses.This is because traditional road design ignores the product that road is a kind of Long-Time Service, Pavement Performance, the construction cost of primary construction process is only analyzed when program decisions, and do not do the careful of Comprehensive from the Pavement Performance needed for the whole life cycle of road and economy and ponder over, more not on during road construction consume the impact of the energy on environmental emission, therefore from road life cycle, current shortage to road design and decision-making, considers that the requirement of Pavement Performance and first stage of construction are to the requirement of environmental emission, thus can not obtain the real pavement design scheme comprehensively optimized.

Summary of the invention

The object of the present invention is to provide a kind of a kind of decision-making technique of road surfacing scheme considering pavement performance, ambient influnence, financial cost from life-cycle processes.

For achieving the above object, the inventive method comprises:

The corresponding index being relevant to pavement characteristics, economic performance and emission performance in each road surfacing scheme is estimated;

Respectively standardization is carried out by large or minimal type attribute to each index of estimation, obtains corresponding standardized index value;

Index weights coefficient corresponding to each index is set, and the comprehensive evaluation value that setup algorithm obtains corresponding road surfacing scheme is carried out to weight coefficient and standardized index value, choose there is the highest comprehensive evaluation value road surfacing scheme as final employing scheme.

Described index comprises the first class index of pavement characteristics, economic performance and emission performance, and each first class index at least comprises a two-level index; Each first class index and two-level index are respectively arranged with corresponding one-level weight coefficient and secondary weight coefficient; Described setup algorithm be all two-level index in a road surfacing scheme standardized index value respectively with to should two-level index secondary weight coefficient and to the long-pending of the first class index weight coefficient of first class index corresponding to this two-level index and, namely $V=\underset{i=1}{\overset{3}{\Σ}}(x_{ij}^{*}\×w_i\×w_{ij}):$

In formula: be the standardized value of jth item two-level index in i-th first class index, w _ibe i-th one-level weight factor, w _ijit is the secondary weight factor of jth item two-level index in i-th first class index.

The first class index subordinate of described pavement characteristics comprises water steady layer fatigue life, bitumen layer set deformation volume and bitumen layer planeness index three two-level index; The first class index subordinate of described economic performance comprise each year in the given period net present value (NPV) and a two-level index; The first class index of described emission performance be correspond to that energy consumption produces comprise global warming substances, acidification effect material, health risk material and particulate matter four two-level index; Each two-level index included by emission performance first class index also at least comprises more than one factor of influence, and each factor of influence is provided with characteristic of correspondence parameter; Described global warming two-level index comprises CO ₂, CH ₄and N ₂o tri-factors of influence, character pair parameter is followed successively by 1, and 25,298; Described acidification effect two-level index comprises SO ₂, NO _xand NH ₃three factors of influence, character pair parameter is followed successively by 1, and 0.7,1.88; Described health risk two-level index comprises SO ₂, NO _x, CO and NMVOC tetra-factors of influence, character pair parameter is followed successively by 0.096,1.2,2.4,0.64; Described particulate matter comprises PM ₁₀and PM _2.5two factors of influence; Character pair parameter is all 1.

All two-level index values included by described emission performance first class index subordinate represent by the equivalent equivalent value of the factor of influence of in this two-level index, and the two-level index of the global warming substances included by described emission performance first class index subordinate, acidification effect material, health risk material uses CO respectively ₂, SO ₂, dichloro-benzenes gas discharging equivalent value represent; The equivalent value EL of i-th two-level index of emission performance first class index subordinate _ifor j factor of influence discharge value I in this i item two-level index _ijrespectively with characteristic of correspondence parameter C _ijlong-pending and, i.e. EI _i=∑ (I _ij× C _ij); .

Corresponding to described pavement characteristics, economic performance and emission performance first class index set by one-level weight coefficient be followed successively by 0.4,0.3,0.3; Road surface special can water steady layer fatigue life included by first class index, bitumen layer set deformation volume and bitumen layer planeness index the secondary weight coefficient of two-level index be followed successively by 0.5,0.3,0.2; In given period included by economic performance first class index each year net present value (NPV) and the secondary weight coefficient of two-level index be 1; The secondary weight coefficient of the energy consumption two-level index included by emission performance first class index, global warming substances two-level index, acidification effect material two-level index, health risk material two-level index and particulate matter two-level index is followed successively by 0.3,0.2,0.3,0.1,0.1;

The estimation of described water steady layer fatigue life comprises:

First, the per day equivalent axles N of initial year Design Lane is determined ₁,

$N_1=AADTT\×DDF\×LDF\×\underset{m=2}{\overset{11}{\Σ}}({\mathrm{VCDF}}_m\×{\mathrm{EALF}}_m)$ (formula 1)

In formula: AADTT is that 2 axles 6 are taken turns and the two-way annual average daily traffic (/ day) of above vehicle; DDF is direction coefficient; LDF is coefficient of lanes; M is type of vehicle numbering; VCDFm is m class type of vehicle breadth coefficient; EALFm is the conversion factor equvalent axle load of m class vehicle;

Then, calculate the equivalent axle load accumulative effect times N e in design period on Design Lane,

$Ne=\frac{\[{(1+\mathrm{\γ})}^t-1\]\×365}{\mathrm{\γ}}{N}_1$ (formula 2)

In formula: t is design period; γ is the annual average rate of increase of the traffic volume in design period; N ₁for the per day equivalent axles of initial year Design Lane;

Finally, water steady layer N fatigue life is calculated _f2,

${\mathrm{lgN}}_{f2}=a-b\left(\frac{k_e{\mathrm{\σ}}_t}{k_s{R}_s}\right)-k_D\mathrm{\β}+lg\left(\frac{k_a}{k_{T2}}\right)$ (formula 3)

In formula: σ t is inorganic binder layer tensile stress at the bottom of layer; Rs is inorganic binder class material flexural tensile strength; β is RELIABILITY INDEX; Ke is the stress intensification factor considering shrinkage crack impact; Ks is the field integrated regulation coefficient of flexural tensile strength design load; Ka is the life enhancement coefficient considering fracture propagation; KT2 is temperature adjustment coefficient; A, b are test regression parameter; k _dfor the standard deviation value of fatigue of materials performance.

The estimation of described bitumen layer set deformation volume comprises:

First, layering is carried out to bitumen layer;

Then, calculated the set deformation volume Ra of each layering by rut test,

$R_a=0.118K{\left(\mathrm{\μ}\right)}^{0.48}{\left(\frac{T}{T_0}\right)}^{2.93}{\left(\frac{p}{p_0}\right)}^{1.80}{\left(\frac{N_{e4}}{N_0}\right)}^{0.48}{\left(\frac{V}{V_0}\right)}^{0.83}\left(\frac{h}{h_0}\right)R_0$

In formula: K is comprehensive correction factor, K=(C ₁+ C ₂depth) 0.9731 ^depth, wherein $C_1=-1.61\×{10}^{-4}{h}_a^2+9.79\×{10}^{-2}{h}_a-17.342,C_2=1.05\×{10}^{-6}{h}_a^2-2.686\×{10}^{-3}{h}_a+1.0798,$ Depth is bitumen layer depth of seam division, and ha is asphalt thickness; And T ₀, p ₀, N ₀, V ₀, h ₀for the test temperature of test specimen corresponding during layering bituminous mixture rut test, pressure, loading number of times, void content and thickness; T is bitumen layer permanent deformation equivalent temperature, and p is bitumen layer layering end face compressed stress, N _e4for in bitumen layer permanent deformation design period, Design Lane design axle carries accumulative effect number of times, V is the Initial Air Void after bitumen layer has been constructed, and h is lift height; μ is for being Design Lane coefficient of wheel tracking transverse distribution; R ₀for the total deformation (mm) of bituminous mixture rut test;

Finally, the set deformation volume of bitumen layer is obtained by calculating each layering set deformation volume.

The estimation of described bitumen layer planeness is the flexible pavement ride quality decay equation IRI=c × e by relevant whole degree index IRI ^dtthe prediction and calculation of carrying out; In formula: c, d are planeness model parameter.

In the described given period, the net present value (NPV) in each year and the half range road surface on Shi Yi 1km road are the summation of routine servicing expense, medium-capital overhauling maintenance costs and the end of term in life-span residual value in the primary construction expense that comprises within the given period of computing unit and life span.

Described global warming substances secondary items two-level index CO ₂equivalent value substitute; Described acidifying substance secondary items two-level index SO ₂equivalent value substitute; Described health risk material secondary items two-level index NO _xequivalent value substitute.

Index for large attribute be by carry out standardized data process, the standardized index value x of the correspondence obtained ^*; Index for minimal type attribute be by carry out standardized data process, the standardized index value x of the correspondence obtained ^*; In formula: x is a certain first class index value in a laying scheme, min be each alternative in minimum value in this first class index values all, max is the maximum value in each alternative in this first class index values all.

The inventive method carries out integrated decision-making from the design of pavement characteristics, economic performance and emission performance many factors road pavement, and in pavement characteristics, consider the performance in relevant pavement life cycle, make pavement design more consider cost performance, therefore the inventive method can make pavement design scheme that is more scientific, more economical, more environmental protection; Simultaneously in measuring and calculating process, adopt Standardization Act to each index normalized, and use weight coefficient, characteristic parameter, make the inventive method when calculating not only easy but also can objective, quantitatively provide desired data.

Detailed description of the invention

Below in conjunction with instantiation, the present invention is specifically described.

, an arterial highway for Class I highway standard, two-way six-lane, designed driving speed 100km/h, width of subgrade is 31m, design period t=15, starting year annual average daily traffic is 10923pcu/d (/ day), estimates traffic average annual growth rate γ=6.9%.In conjunction with arterial highway feature, be designed with the alternative of A, B, C, D tetra-kinds of road surfacings, see the following form a.

Table a

The final decision of above-mentioned four road surfacing schemes is carried out in the steps below.

Step one, estimates the corresponding index being relevant to pavement characteristics, economic performance and emission performance in each road surfacing scheme.

The corresponding index of above-mentioned pavement characteristics, economic performance and emission performance is as first class index.

1. road pavement characteristic is estimated

The present invention is based on from road life cycle to consider the special energy in road surface, the first class index of pavement characteristics have employed and comprises water steady layer fatigue life, bitumen layer set deformation volume and bitumen layer planeness index three two-level index, estimates one by one below to these three two-level index.

(1) N fatigue life of the steady layer of water _f2estimation

Determine vehicle equivalence axle-load exchanging coefficient according to the two-way annual average daily traffic of vehicle, determine the per day equivalent axles N of initial year Design Lane by formula 1 below ₁.

$N_1=AADTT\×DDF\×LDF\×\underset{m=2}{\overset{11}{\Σ}}({\mathrm{VCDF}}_m\×{\mathrm{EALF}}_m)$ (formula 1)

In formula: AADTT is that 2 axles 6 are taken turns and the two-way annual average daily traffic (/ day) of above vehicle, calculate actual initial year Design Lane daily traffic volume by project overview and traffic parameter, AADTT=10923; DDF is the DDF=0.55 of direction coefficient, the present embodiment; LDF is the LDF=0.75 of coefficient of lanes, the present embodiment; M is type of vehicle numbering, the m=10 of the present embodiment; VCDFm is m class type of vehicle breadth coefficient, the VCDF of the present embodiment ₂=0.28, VCDF ₃=0.233, VCDF ₄=0.027, VCDF ₅=0.05, VCDF ₆=0.083, VCDF ₇=0.075, VCDF ₈=0.121, VCDF ₉=0.065, VCDF ₁₀=0.066; EALFm is the EALF of the conversion factor equvalent axle load of m class vehicle, the present embodiment ₂=0.8, EALF ₃=0.4, EALF ₄=0.7, EALF ₅=0.6, EALF ₆=1.3, EALF ₇=1.4, EALF ₈=1.4, EALF ₉=1.5, EALF ₁₀=2.4, therefore calculated by formula (1):

According to the per day equivalent axles N of initial year Design Lane ₁, design period etc., calculate the equivalent axle load accumulative effect times N e in design period on Design Lane by formula 2.

$Ne=\frac{\[{(1+\mathrm{\γ})}^t-1\]\×365}{\mathrm{\γ}}{N}_1$ (formula 2)

According to the design period t=15 (year) arranged in the present embodiment, estimate traffic average annual growth rate γ=6.9%, then:

Ne is the equivalent axle load accumulative effect number of times (secondary) in design period on Design Lane; T is design period (year), the present embodiment,

$Ne=\frac{\[{(1+\mathrm{\γ})}^t-1\]\×365}{\mathrm{\γ}}{N}_1=\frac{\[{(1+6.9\%)}^{15}-1\]\×365}{6.9\%}\×4506=4.101\×{10}^7.$

Water steady layer fatigue life, the i.e. tired life N of inorganic binder layer is calculated according to the steady end pressure layer by layer of water _f2(secondary), calculates by following formula 3,

${\mathrm{lgN}}_{f2}=a-b\left(\frac{k_e{\mathrm{\σ}}_t}{k_s{R}_s}\right)-k_D\mathrm{\β}+\lg \left(\frac{k_a}{k_{T2}}\right)$ (formula 3)

Inorganic binder layer wherein comprises cement stabilized type, cement-fly ash Stabilized, lime stabilization class, lime-flyash Stabilized; σ _tfor inorganic binder layer tensile stress at the bottom of layer (MPa); Rs is inorganic binder class material flexural tensile strength (MPa), and the length of time of cement stabilized type, cement-fly ash Stabilized Materials is 90d, and the length of time of lime stabilization class, lime-flyash Stabilized Materials is 180d; β is RELIABILITY INDEX, and according to road quality classification value, speedway gets 1.65, and Class I highway gets 1.28, and Class II highway gets 1.04, and Class III highway gets 0.84, and Class IV highway gets 0.52; Ke is the stress intensification factor considering shrinkage crack impact, according to inorganic binder class material unconfined compression strength and thickness, determines by table 1; Ks is the field integrated regulation coefficient of flexural tensile strength design load, determines by interpolation method according to table 2; Ka is the life enhancement coefficient considering fracture propagation, determines by interpolation method according to table 3; k _t2for temperature adjustment coefficient; A, b are test regression parameter, determine by table 4; k _dfor considering fatigue of materials performance standard deviate, determine by table 4.

Table 1 stress intensification factor ke

Note: cement stabilized type, cement-fly ash Stabilized Materials length of time are 90d, lime stabilization class, lime-flyash Stabilized Materials length of time is 180d.

The field integrated regulation coefficient ks of table 2 flexural tensile strength design load

Table 3 fracture propagation coefficient k a

The above inorganic binder layer thickness (mm) in calculation level position	150	200	250	300	350	400	≥420
								ka	1.36	1.89	2.63	3.65	5.06	7.03	8.0

Table 4 inorganic binder layer fatigue failure model parameter k _d

Material type

a

B

k D

[0065]

Cement stabilized granular or two ash stability pellet	13.24	12.52	1.16
				Cement stabilizing fine grained soils	12.18	12.79	0.61

Above-mentioned A, B, C, D tetra-alternative road surfacing scheme is to the selection of parameter each in formula 3 and N fatigue life of cement stabilized macadam base that obtains according to this formulae discovery _f2, in table 5.

Table 5 different schemes inorganic binder basic unit fatigue life

(2) estimation of bitumen layer permanent deformation

First, carry out layering to bitumen layer, carry out layering according to following requirements to bitumen layer, the depth of seam division depth of its each bitumen layer is respectively:

Surface course, adopts 10mm ~ 20mm to be a layering;

Second layer bitumen layer, adopts 20mm ~ 25mm to be a layering;

Third layer bitumen layer, as a layering when thickness is not more than 100mm, is divided into two layerings when being greater than 100mm;

4th layer and following bitumen layer, as a layering.

Then, by the set deformation volume Ra of rut test and each layering of following formulae discovery,

$R_a=0.118K{\left(\mathrm{\μ}\right)}^{0.48}{\left(\frac{T}{T_0}\right)}^{2.93}{\left(\frac{p}{p_0}\right)}^{1.80}{\left(\frac{N_{e4}}{N_0}\right)}^{0.48}{\left(\frac{V}{V_0}\right)}^{0.83}\left(\frac{h}{h_0}\right)R_0,$ (formula 4)

In formula: K is comprehensive correction factor, and K is by following formulae discovery

K=(C ₁+ C ₂depth) 0.9731 ^depth, (formula 5)

The value of depth: surface course depth gets 15mm, other are layered as the degree of depth of road table apart from pitch layering mid point.

C in formula 4 ₁, C ₂calculate according to following formula 6,7 respectively

$C_1=-1.61\×{10}^{-4}{h}_a^2+9.79\×{10}^{-2}{h}_a-17.342,$ (formula 6)

$C_2=1.05\×{10}^{-6}{h}_a^2-2.686\×{10}^{-3}{h}_a+1.0798,$ (formula 7)

In formula: ha is bitumen layer gross thickness, when ha is greater than 200mm, get 200mm; And T ₀, p ₀, N ₀, V ₀, h ₀for the test temperature of test specimen corresponding during layering bituminous mixture rut test, pressure, loading number of times, void content and thickness; T is bitumen layer permanent deformation equivalent temperature, and p is bitumen layer layering end face compressed stress, N _e4for in bitumen layer permanent deformation design period, Design Lane design axle carries accumulative effect number of times, V is the Initial Air Void after bitumen layer has been constructed, and h is lift height; μ is Design Lane coefficient of wheel tracking transverse distribution, speedway 0.5, other standard highways 0.45; R ₀for the total deformation of bituminous mixture rut test.

For A scheme, pitch degree of depth 130mm, skin depth gets 15mm, obtains $C_1=-1.61\×{10}^{-4}{h}_a^2+9.79\×{10}^{-2}{h}_a-17.342=-1.61\×{10}^{-4}\×{130}^2+9.79\×{10}^{-2}\×130-17.342=-7.3359$ $C_2=1.05\×{10}^{-6}{h}_a^2-2.686\×{10}^{-3}{h}_a+1.0798=1.05\×{10}^{-6}\×{130}^2-2.686\×{10}^{-3}\×130+1.0798=0.748365$ K＝(C ₁+C ₂·depth)·0.9731 ^depth＝(-7.3359+0.748365×15)×0.9731 ¹⁵＝2.5838

A scheme top layer 15mm is permanently deformed to $\begin{array}{c}{R}_a=0.118K{\left(\mathrm{\μ}\right)}^{0.48}{\left(\frac{T}{T_0}\right)}^{2.93}{\left(\frac{p}{p_0}\right)}^{1.80}{\left(\frac{N_{e4}}{N_0}\right)}^{0.48}{\left(\frac{V}{V_0}\right)}^{0.83}\left(\frac{h}{h_0}\right)R_0\\ =0.118\×2.584\×{0.45}^{0.48}\×{(29.64/60)}^{2.93}\×{(0.7023/0.707)}^{1.80}\×{(4.9\×{10}^6/2520)}^{0.48}\×\end{array}$ ${(3.5/6)}^{0.83}\×(15/50)\×1.217=0.2301mm;$ In like manner, the second layer degree of depth gets 22.5mm, the third layer degree of depth gets 40mm, 4th layer depth gets 60mm, and the layer 5 degree of depth gets 80mm, and the layer 6 degree of depth gets 100mm, the layer 7 degree of depth gets 120mm, can calculate the permanent deformation of each layer, the set deformation volume of each level of B, C, D scheme calculates and no longer enumerates, and final calculation result is as shown in table 6.

The set deformation volume of table 6 bitumen layer in life cycle (mm)

Scheme	A	B	C	D
					Set deformation volume	21.95	8.80	27.57	7.9

(3) estimation of bitumen layer planeness

Be undertaken by calculating the estimation of bitumen layer planeness index IRI to the estimation of bitumen layer planeness, flexible pavement ride quality decay equation (formula 8 see following) of foundation carries out the estimation of surface evenness index.

IRI=c × e ^dt(formula 8)

In formula: c, d are planeness model parameter, according to asphalt thickness, by table 7 value.

Table 7 planeness model parameter

Calculate according to formula 8, get c=1.29, d=0.09, the option A planeness disintegration index of the 15th year is IRI=1.29 × e ^{(0.09 × 15)}=4.9761, in life cycle, the planeness index of each road surfacing scheme is as shown in table 8.

The planeness index IRI (m/km) of table 8 flexible pavement in life cycle

Scheme	A	B	C	D
					Planeness index	4.9761	4.9761	4.9415	4.9415

2. pair economic performance is estimated

Estimate by the net present value (NPV) in year each in the given period with carry out valuation calculating to economic performance, in given period, the net present value (NPV) in each year and the half range road surface on Shi Yi 1km road are the summation of routine servicing expense, medium-capital overhauling maintenance costs and the end of term in life-span residual value in the primary construction expense that comprises within the given period of computing unit and design period, see following formula 9.

$NPV=\underset{t=o}{\overset{n}{\Σ}}NCFt(P/F,i,t)$ (formula 9)

In formula: NPV is the net present value (NPV) (unit) of certain scheme or project; N is the given period; NCFt is the cash flow (unit) of t, and the present embodiment gets t=15; (P/F, i, t) is present value factor, represents and fund is converted to net present value (NPV), and discount rate is i, and the cycle is t), and i is the basic discount rate of setting, and the present embodiment gets i=8%; According to.Be scaled net present value (NPV) according to discount rate, each scheme gathers as shown in table 9 at life cycle cost.

Table 9 different schemes functional unit whole life costing gathers

3. the estimation of pair emission performance

The first class index of emission performance comprises global warming substances, acidification effect material, health risk material and particulate matter four two-level index caused by energy consumption, each two-level index in these four two-level index also at least comprises the factor of influence of, see table 10.The two-level index of global warming substances comprises because of the emission of substance caused that consumes energy: CO2, CH ₄and N ₂o tri-factors of influence; The two-level index of acidification effect material comprises the material because of the discharge caused of consuming energy: SO ₂, NO _x(NO _xjust be nitrogen oxide) and NH ₃three factors of influence; The two-level index of health risk material comprises because of the emission of substance caused that consumes energy: SO2, NO _x(nitrogen oxide), CO and NMVOC (non-methane VOC) four factors of influence; The two-level index of particulate matter comprises because of the emission of substance PM caused that consumes energy ₁₀and PM _2.5two factors of influence.The two-level index relating to emission performance represents by the equivalent equivalent value of the wherein factor of influence corresponding to this two-level index.Therefore, the equivalent value EL of i-th two-level index of emission performance first class index subordinate _ifor j factor of influence discharge value I in this i item two-level index _ijrespectively with characteristic of correspondence parameter C _ijlong-pending and, that is:

EI _i=∑ (I _ij× C _ij) (formula 10),

I wherein _ijbe the jth two-level index discharge value in i-th secondary items, C _ijit is the characterization factor of the jth two-level index in i-th secondary items.Such as, in the A scheme two-level index CO of global warming secondary items ₂the equivalent value of discharge is expressed as: EI ₁=(1.12 × 10 ⁶) × 1+ (2.79 × 10 ³) × 25+ (1.17 × 10 ¹) × 298=1.19 × 10 ⁶(MJ).All the other equivalent value computational methods of emission performance first class index subordinate identically to be listed no longer one by one in this, and concrete numerical value is see table 11.

The factor of influence of table 10 two-level index and correspondence, characteristic parameter

Table 11 four scheme government pollution emissions gas equivalent calculation result

Step 2, carries out standardization to each index of estimation respectively by large or minimal type attribute, obtains corresponding standardized index value.

Respectively standardization is carried out by very big and minimum to each desired value that above-mentioned steps obtains, to the tired life index of large index (the larger performance of numerical value is better) layer as steady in water, presses (formula 11) carries out standardized data process, presses minimal type index (the less performance of numerical value is better) such as bitumen layer permanent deformation (formula 12) carries out standardized data process, wherein: x is the desired value of a certain two-level index in a laying scheme, min be each alternative in minimum value in this two-level index values all, max is the maximum value in each alternative in this two-level index values all.

For A scheme, wherein the standardized index value of water steady layer index fatigue life calculates, and from table 5, first finds out the maximum value of A, B, C, D tetra-this index in scheme: 6.89 × 10 ¹⁰, minimum value: 2.38 × 10 ¹⁰, calculate by formula 11 in like manner the standardized index value of B scheme water steady layer index fatigue life calculates $x_{12}^{*}=\frac{x-min}{max-min}=\frac{2.87\×{10}^{10}-2.38\×{10}^{10}}{6.89\×{10}^{10}-2.38\×{10}^{10}}=0.11,$ The computational process of other each indexs is listed no longer one by one, and the standard value of all indexs of four schemes is as shown in table 12.

Table 12 each road surface scheme standardize criteria result

Step 3, index weights coefficient corresponding to each index is set, and the comprehensive evaluation value that setup algorithm obtains corresponding road surfacing scheme is carried out to weight coefficient and standardized index value, choose there is the highest comprehensive evaluation value road surfacing scheme as final employing scheme

Arrange the index weights coefficient of pavement characteristics, economic performance and emission performance first class index and each index of corresponding two-level index, each first class index and two-level index are respectively arranged with corresponding one-level weight coefficient and secondary weight coefficient, as table 13.The standardized index value of comprehensive evaluation value V corresponding to all two-level index of the program of each road surfacing scheme and the one-level weight coefficient corresponding to this two-level index and the secondary weight coefficient corresponding to this two-level index long-pending and, that is:

$V=\underset{i=1}{\overset{3}{\Σ}}(x_{\mathrm{ij}}^{*}\×w_i\×w_{\mathrm{ij}})$ (formula 13)

In formula: V is comprehensive index value, for the standardized value of each index, w _ifor one-level weight factor, w _ijfor two-level index weight factor.

The different index of table 13 and corresponding weight factor thereof

The comprehensive evaluation value V of such as A scheme _abe exactly be relevant to all two-level index corresponding to pavement characteristics, economic performance and emission performance first class index in the program standard desired value respectively with the secondary weight coefficient of corresponding index and the long-pending of one-level weight coefficient and, therefore according to the data that formula 13 and table 12,13 provide, to the comprehensive evaluation value V of A scheme _abe calculated as follows:

V _A＝(1.00×0.4×0.5+0.29×0.4×0.3+0.00×0.4×0.2)+0.43×0.3×1+(0.42×0.3×0.3+0.42×0.3×0.2+0.38×0.3×0.3+0.49×0.3×0.1+0.35×0.3×0.1)＝0.49，

The comprehensive evaluation value of all the other schemes calculates identical therewith, and list no longer one by one, the option A calculated, the comprehensive evaluation value of B, C, D are respectively 0.49,0.73,0.22,0.79.

According to comprehensive evaluation value, this value of D scheme is the highest, therefore, choose the D scheme with the highest comprehensive evaluation value as the road surfacing scheme finally adopted.

Claims (11)

1. a decision-making technique for road surfacing scheme, is characterized in that: comprise

The corresponding index being relevant to pavement characteristics, economic performance and emission performance in each road surfacing scheme is estimated;

Respectively standardization is carried out by large or minimal type attribute to each index of estimation, obtains corresponding standardized index value;

Index weights coefficient corresponding to each index is set, and the comprehensive evaluation value that setup algorithm obtains corresponding road surfacing scheme is carried out to weight coefficient and standardized index value, choose there is the highest comprehensive evaluation value road surfacing scheme as final employing scheme.

2. the decision-making technique of a kind of road surfacing scheme according to claim 1, is characterized in that: described index comprises the first class index of pavement characteristics, economic performance and emission performance, and each first class index at least comprises a two-level index; Each first class index and two-level index are respectively arranged with corresponding one-level weight coefficient and secondary weight coefficient; Described setup algorithm be all two-level index in a road surfacing scheme standardized index value respectively with to should two-level index secondary weight coefficient and to the long-pending of the first class index weight coefficient of first class index corresponding to this two-level index and, namely

In formula: be the standardized value of jth item two-level index in i-th first class index, w _ibe i-th one-level weight factor, w _ijit is the secondary weight factor of jth item two-level index in i-th first class index.

3. the decision-making technique of a kind of road surfacing scheme according to claim 2, is characterized in that: the first class index subordinate of described pavement characteristics comprises water steady layer fatigue life, bitumen layer set deformation volume and bitumen layer planeness index three two-level index; The first class index subordinate of described economic performance comprise each year in the given period net present value (NPV) and a two-level index; The first class index of described emission performance be correspond to that energy consumption produces comprise global warming substances, acidification effect material, health risk material and particulate matter four two-level index; Each two-level index included by emission performance first class index also at least comprises more than one factor of influence, and each factor of influence is provided with characteristic of correspondence parameter; Described global warming two-level index comprises CO2, CH ₄and N ₂o tri-factors of influence, character pair parameter is followed successively by 1, and 25,298; Described acidification effect two-level index comprises SO ₂, NO _xand NH ₃three factors of influence, character pair parameter is followed successively by 1, and 0.7,1.88; Described health risk two-level index comprises SO ₂, NO _x, CO and NMVOC tetra-factors of influence, character pair parameter is followed successively by 0.096,1.2,2.4,0.64; Described particulate matter comprises PM ₁₀and PM _2.5two factors of influence; Character pair parameter is all 1.

4. the decision-making technique of a kind of road surfacing scheme according to claim 3, it is characterized in that: all two-level index values included by described emission performance first class index subordinate represent by the equivalent equivalent value of the factor of influence of in this two-level index, the two-level index of the global warming substances included by described emission performance first class index subordinate, acidification effect material, health risk material uses CO respectively ₂, SO ₂, dichloro-benzenes gas discharging equivalent value represent; The equivalent value EL of i-th two-level index of emission performance first class index subordinate _ifor j factor of influence discharge value I in this i item two-level index _ijrespectively with characteristic of correspondence parameter C _ijlong-pending and, i.e. EI _i=∑ (I _ij× C _ij).

5. the decision-making technique of a kind of road surfacing scheme according to claim 3, is characterized in that: corresponding to described pavement characteristics, economic performance and emission performance first class index set by one-level weight coefficient be followed successively by 0.4,0.3,0.3; The secondary weight coefficient of the two-level index of the steady layer of the water included by pavement characteristics first class index fatigue life, bitumen layer set deformation volume and bitumen layer planeness index is followed successively by 0.5,0.3,0.2; In given period included by economic performance first class index each year net present value (NPV) and the secondary weight coefficient of two-level index be 1; The secondary weight coefficient of the energy consumption two-level index included by emission performance first class index, global warming substances two-level index, acidification effect material two-level index, health risk material two-level index and particulate matter two-level index is followed successively by 0.3,0.2,0.3,0.1,0.1.

6. the decision-making technique of a kind of road surfacing scheme according to claim 3, is characterized in that: the estimation of described water steady layer fatigue life comprises:

First, the per day equivalent axles N of initial year Design Lane is determined ₁,

(formula 1)

In formula: AADTT is that 2 axles 6 are taken turns and the two-way annual average daily traffic (/ day) of above vehicle; DDF is direction coefficient; LDF is coefficient of lanes; M is type of vehicle numbering; VCDFm is m class type of vehicle breadth coefficient; EALFm is the conversion factor equvalent axle load of m class vehicle;

Then, calculate the equivalent axle load accumulative effect times N e in design period on Design Lane,

(formula 2)

In formula: t is design period; γ is the annual average rate of increase of the traffic volume in design period; N ₁for the per day equivalent axles of initial year Design Lane;

Finally, water steady layer N fatigue life is calculated _f2,

(formula 3)

In formula: σ t is inorganic binder layer tensile stress at the bottom of layer; Rs is inorganic binder class material flexural tensile strength; β is RELIABILITY INDEX; Ke is the stress intensification factor considering shrinkage crack impact; Ks is the field integrated regulation coefficient of flexural tensile strength design load; Ka is the life enhancement coefficient considering fracture propagation; KT2 is temperature adjustment coefficient; A, b are test regression parameter; k _dfor the standard deviation value of fatigue of materials performance.

7. the decision-making technique of a kind of road surfacing scheme according to claim 3, is characterized in that: the estimation of described bitumen layer set deformation volume comprises:

First, layering is carried out to bitumen layer;

Then, calculated the set deformation volume Ra of each layering by rut test,

In formula: K is comprehensive correction factor, K=(C ₁+ C ₂depth) 0.9731 ^depth, wherein

depth is bitumen layer depth of seam division, and ha is asphalt thickness; And T ₀, p ₀, N ₀, V ₀, h ₀for the test temperature of test specimen corresponding during layering bituminous mixture rut test, pressure, loading number of times, void content and thickness; T is bitumen layer permanent deformation equivalent temperature, and p is bitumen layer layering end face compressed stress, N _e4for in bitumen layer permanent deformation design period, Design Lane design axle carries accumulative effect number of times, V is the Initial Air Void after bitumen layer has been constructed, and h is lift height; μ is for being Design Lane coefficient of wheel tracking transverse distribution; R ₀for the total deformation (mm) of bituminous mixture rut test;

Finally, the set deformation volume of bitumen layer is obtained by calculating each layering set deformation volume.

8. the decision-making technique of a kind of road surfacing scheme according to claim 3, is characterized in that: the estimation of described bitumen layer planeness is the flexible pavement ride quality decay equation IRI=c × e by relevant whole degree index IRI ^dtthe prediction and calculation of carrying out,

In formula: c, d are planeness model parameter.

9. the decision-making technique of a kind of road surfacing scheme according to claim 3, is characterized in that: in the described given period, the net present value (NPV) in each year and the half range road surface on Shi Yi 1km road are the summation of routine servicing expense, medium-capital overhauling maintenance costs and the end of term in life-span residual value in the primary construction expense that comprises within the given period of computing unit and life span.

10. the decision-making technique of a kind of road surfacing scheme according to claim 3, is characterized in that: the equivalent value of described global warming substances secondary items two-level index CO2 substitutes; Described acidifying substance secondary items two-level index SO ₂equivalent value substitute; Described health risk material secondary items two-level index NO _xequivalent value substitute.

The decision-making technique of 11. a kind of road surfacing schemes according to claim 1, is characterized in that: the index for large attribute be by carry out standardized data process, the standardized index value x of the correspondence obtained ^*; Index for minimal type attribute be by carry out standardized data process, the standardized index value x of the correspondence obtained ^*.

In formula: x is a certain first class index value in a laying scheme, min be each alternative in minimum value in this first class index values all, max is the maximum value in each alternative in this first class index values all.