CN101477110B - Asphalt mixture construction depth and its durability indoor detection method - Google Patents

Abstract

The invention relates to an indoor detection method of bitumen mixture structural depth and durability, which belongs to the field of road design measurement. The detection method comprises the following steps: making a sample and measuring the area S of a to-be-measured surface of the sample; spreading standard sand with known density rho on the to-be-measured surface of the sample to obtain sand spreading quantity G, thereby obtaining a structural depth value through the formula that DS is equal to G/(rho*S); and combining the prior standard track test to estimate the durability of bitumen mixture structural depth according to variations in structural depth before and after track test. Because the detection method is carried out indoors and replaces to-be-measured road surface by the sample, has strong maneuverability, accurate detection data and high detection efficiency, the method can estimate bitumen mixture during design stage and is favorable for engineering construction units to select and estimate bitumen mixture.

Description

Asphalt mixture construction depth and durability indoor detection method thereof

Technical field

The present invention relates to the highway layout field of measurement, particularly relate to the indoor measuring method of a kind of asphalt mixture construction depth and permanance thereof.

Background technology

Guarantee that the road surface has good cling property and permanance thereof, be to guarantee traffic safety, satisfy one of basic assurance of surface feature.The current index of estimating pavement skid resistance condition in the world is mainly friction factor and construction depth; These indexs just engineering is built up after the road pavement cling property estimate, present do not have perfect detection method and index in design phase Evaluation of asphalt mixture cling property and permanance thereof in the world.

Detect in the index at road quality; Cling property and permanance thereof are two important index; And the construction depth of asphalt is that key index, the especially permanance of the various asphalts of road surface antiskid layer of measurement pavement skid resistance property and permanance and the size of construction depth value thereof are important performance indexes of road construction construction medium pitch Mixture Ratio design.The method of Evaluation of asphalt mixture construction depth mainly contains surperficial sand patch method, laser construction depth method etc. at present.The surface sand patch method refers to broom or hairbrush near the road cleaning the measuring point is clean; The uniform sand of certain volume density of known weight is poured near the road surface the measuring point; And to pave circular as far as possible, measures the sanding area, and according to the volume calculation road surface construction degree of depth of sand.This method is applicable to measures the road surface construction degree of depth, and its shortcoming is that operability is relatively poor, cannot measure construction depth and permanance thereof simultaneously; Outdoor disturbing factor is too many; Therefore measurement data is extensive, such as the bad accurate Calculation of the area of sanding, sanding whether just in time be paved with or whether spread surpass to blow in structure space and outdoor, the road surface wetness these all be difficult to operation and control; Subjectivity is too strong, performance that can not accurate objective reaction pavement asphalt compound; It is extremely low that another makes things convenient for it to test the speed, and labour intensity is big during survey, and security is also relatively poor; Laser texture meter method produces infrared ray with the high-speed pulse semiconductor laser and projects road surface; Scattered beam is focused on the photodiode of linear layout by receiver lens from the projecting plane; The maximum diode location of reception light has provided this and has arrived the distance of road surface in a flash; Can draw construction depth through series of computation, detection speed is 5km/h, i.e. people's walking speed.The laser texture meter is claimed the laser texture tester again, though have convenient transportation, swift to operate, the advantage of good reliability.But it is mainly used also can only be on the fast detecting of surfacing.Ordinary people's general knowledge can be known, detects the cling property and the endurance quality on the road surface that making is good, can only obtain a measurement data, and can not road pavement design directive function; Afterwards detect if can only pave the way earlier, so detected underproof road surface is overhauled causing resource and economic dual loss.

Integrate and see; At present all detection methods all can only be on the outdoor detection good road surface of making; Fail to estimate the cling property and the permanance thereof of the asphalt of design phase; And in operation, also all have many shortcomings, or poor operability causes testing result extensive and can not objective evaluation compound to be measured; Need complicated instrument and equipment, inconvenient conventional design unit is to the evaluation and the detection of large batch of design proportioning.

Summary of the invention

The present invention is directed to the deficiency in above-mentioned field.Proposed construction depth and the method for permanance thereof of the asphalt in a kind of detection design stage, it can be at in-house operation, and the operability that has is good, objective and accurate characteristics.

A kind of indoor detection method of asphalt mixture construction depth, its step is following:

1). make test specimen,

2). detect test specimen construction depth DS:

A). the one side of choosing test specimen is to be measured, and survey area S is paved with normal sand.

B). obtain the gross weight G of the normal sand of spreading,

C). the construction depth DS of calculation testing piece:

$\mathrm{DS}=\frac{G}{\mathrm{\ρ}\×S},$ ρ is the density of normal sand.

A kind of indoor detection method of asphalt mixture construction depth permanance, its step is following:

1) detection method of employing claim 1 detects the construction depth DS of test specimen,

2) one side that test specimen is detected in step 1) is carried out wheel tracking test,

3) treat test specimen cooling after, detect the construction depth DS ' of rut wheelmark part in the test specimen:

A). measure the area S ' at wheelmark position, and partly spread normal sand at the rut wheelmark of test specimen,

B). obtain the gross weight G ' of the normal sand of spreading,

C). the construction depth DS ' of calculation testing piece:

${\mathrm{DS}}^{\′}=\frac{G^{\′}}{\mathrm{\ρ}\×S^{\′}},$ ρ is the density of normal sand,

4) calculate remaining rate: the DS ' of construction depth/DS.

Before the construction depth step of rut wheelmark part, the test specimen with rut wheelmark part cuts down as part to be had a try earlier in the said detection test specimen.

Said test specimen is carried out test specimen being placed 60 ℃ of insulations 6-8 hour before the wheel tracking test, and under uniform temp, carry out wheel tracking test.

During said detection construction depth step, test specimen is under 18--22 ℃, is incubated 6-8 hour.

The said step of obtaining the normal sand weight of spreading is following:

A). its weight of weighing G after the test specimen drying ₁

B). take by weighing the gross weight G of test specimen and its surface standard normal sand ₂,

C). the weight of the normal sand of spreading is G ₂-G ₁

The normal sand of the preferred 0.3～0.6mm of said normal sand.

Said making test specimen is to adopt marshall compaction forming method or gyratory compaction forming method, and the specification of said test specimen is the cylinder specimen of diameter 100mm to 150mm.

The detection method of detection asphalt mixture construction depth provided by the invention; The construction depth of asphalt that can the detection design stage; This detection method is made into test specimen with asphalt to be measured; Can calculate construction depth through the weight that obtains the normal sand of spreading, the area at test specimen sanding position, the density of normal sand at the surperficial sand patch method of indoor employing.Because asphalt to be tried can have been processed a certain size test specimen, can accurately control specification and shape that test specimen is made, thereby can measure accurate area; Be to obtain the sanding amount behind the first sanding during detection, so only consider fully to complete normal sand with to be measured during sanding, unnecessary normal sand can clean out; It is simple to operate; Be easy to standard, promptly operability is very good, and the more outdoor pavement detection of detection data that obtains is accurately reliable; This detection method can provide the guidance that objectively is of practical significance to selection of engineering construction unit and designing asphalt mixture proportioning, helps setting up the standardization detection means that road quality detects.

The present invention also provides the detection method of asphalt mixture construction depth permanance; Be that construction depth detection method with above-mentioned acquisition combines with existing common wheel tracking test; Through test specimen is carried out wheel tracking test, the permanance of coming the Evaluation of asphalt mixture construction depth with the variation of the test specimen construction depth before and after the wheel tracking test.Owing to adopted the detection method of the construction depth of the present invention's acquisition; Guaranteed that its detection mode obtains the accuracy and the objectivity of data; The construction depth permanance that this method is estimated is also very accurately objective; This detection method is a kind of desirable selection for evaluation of engineering construction unit or design alternative asphalt proportioning, and is workable, utilizes instruments such as existing rut appearance just can accomplish detection indoor.

In permanance of the present invention detects, be comparison, so the construction depth that obtains behind the wheel tracking test can detect on original test specimen to rut part construction depth before and after wheel tracking test; Also can wheelmark partly be cut down again and detect; The present invention preferably cuts down the test specimen of rut part, and cuts into the rectangle of rule, directly wheelmark is partly carried out sanding, accurately measures to be measured operation such as area of wheelmark part; Raising makes operability, and it is also more accurately reliable to detect data.

In the wheel tracking test that detects permanance; Because the permanance of construction depth mainly is meant the construction depth permanance on road surface in summer, detect data as far as possible near True Data, before wheel tracking test in order to make the permanance that obtains; The present invention is with test specimen insulation and under uniform temp, carry out wheel tracking test under near the hot conditions of pavement temperature in summer; Make the situation of test specimen when summer, the road surface was frayed in the wheel tracking test similar, the preferred 60 ℃ of insulations of the present invention 6-8 hour, and under this temperature, carry out wheel tracking test; This temperature and China's most of areas bituminous pavement in summer temperature are coincide, and being incubated 6-8 hour is to make the inside and outside state of test specimen reach uniformity.This condition is suitable for the detection and the prediction of the highway asphalt mixture of most of areas.

Among the present invention, before detecting construction depth, test specimen is placed under the 18-22 degrees celsius; Be incubated about 6 hours; And under this stationary temperature, carry out follow-up detecting operation, and insulation helps test specimen and reaches the state of homogeneous to outside surface internally, and 18-22 degree centigrade meets China's most of areas normal temperature temperature; Make and detect the data fit actual value, also make this detection method be easy to various places and carry out.In addition; To the asphalt mixture construction depth that the one side that test specimen makes an experiment carried out repetition be detected before the wheel tracking test in the present invention with afterwards; It is consistent that the temperature that adopts in the duplicate detection process is wanted, and avoids causing that by the temperature difference asphalt soft durometer, structure space change, thereby disturb the construction depth permanance to detect the reliability of data; Adopt 18-22 degree centigrade normal temperature environment, under the general room environment, be easy to realize repetitive operation.

Among the present invention, obtaining the accurate weight of the normal sand of spreading, is an accurately objective key factor of warranty test.The present invention preferably adopts the decrement method, and test specimen face to be measured is paved with normal sand, takes by weighing the weight difference of test specimen before and after the sanding and obtains the weight of normal sand, and simple to operate, data accurately and reliably.

Construction depth detection method of the present invention, the normal sand size that the sanding step is used are very crucial, and too big normal sand can not enrich the structure hole; Can make the detection data less than normal, otherwise too tiny normal sand can get in the slit (like open pores) of the non-construction depth of test specimen; It is bigger than normal to cause detecting data; Thereby influence the validity of data, the present invention selects the normal sand of 0.3-0.6mm for use, is fit to the structure hole of present most of asphalt proportionings.

Detecting the test specimen of construction depth and permanance thereof among the present invention can use the marshall compaction mode to make or gyratory compaction forming method (SGC); The test specimen that this dual mode is made is near the road surface actual conditions; Be that present production standard test specimen generally adopts method, be used to detect make the data of acquisition representative.Carry out the test specimen of common wheel tracking test at present; Be directly moulding in the die trial of rut appearance, directly be used for wheel tracking test after the drying, such test specimen is for detecting construction depth; Be not easy to obtain accurate measurement data; Cause the fines in the asphalt to concentrate on the test specimen surface easily, make inside and outside the test specimen inhomogeneous and surperficial too smoothly, make the construction depth and the permanance thereof that detect not meet actual value.And because the used rut appearance of this detection method is a rut appearance commonly used at present, wherein the specification of die trial is fixed, so the specification of test specimen can not be too big.Can not be too little, too little because the batching of the asphalt of the part of waiting to have a try is generally all approaching with the road surface like the test specimen surface area, can cause the error distortion bigger than normal of test data.The preferred diameter of test specimen specification of made of the present invention is the cylinder specimen of 100mm to 150mm; The test specimen of 100-150mm diameter is made the operations in can meticulous control manufacturing process; Make test specimen uniformity from inside to outside; Test specimen is lightly laborsaving, and detection efficiency is significantly improved, and is suitable for the detection of asphalt batching proportioning in enormous quantities.

Detection method of the present invention adopts surperficial sand patch method; Because detected object is an independently test specimen, and can indoor detection, operability is very strong; Can accurately control the condition that each detects link; Overcome the shortcoming that outdoor road surface sand patch method detects construction depth, just can treat in the design phase and try asphalt and provide accurate objective appraisal, be convenient to engineering department and make and judge accurately and select.Because detection method of the present invention is workable, it is objective and accurate, easy and efficient to detect data, it is beneficial to sets up the standardization detection method.

Embodiment:

Embodiment 1 construction depth detects test

Step 1. is made the marshall compaction test specimen:

(1) the rubble maximum particle diameter of experiment selected is 9.5mm; 4.75mm above rubble content is 65%; 2.36mm above rubble content is 27%, breeze content is 8% grating, 4.8% bitumen aggregate ratio; In the charging process, should guarantee the even of compound, avoid fines directly is deposited in the test specimen surface.Test specimen carries out marshall compaction; Every face hits real 75 times; Compact dimensions is about the cylindrical standard specimen of

h=63.5 ± 1.3mm, and 4 parallel test specimens carry out construction depth and detect test.

2) after the test specimen cooling, the demoulding,

Step 2. is measured the test specimen construction depth:

(1) test specimen is placed in 20 ± 2 ℃ the environment, insulation 6h carries out subsequent step under the uniform temp condition,

(2) bottom surface of selection test specimen, adopt vernier caliper to survey diameters from three angles respectively:

calculating mean value, note is made

(3) after the vacuum drying, take by weighing the dry weight G of test specimen _Qi=1156.34g with the normal sand of 0.3～0.6mm of known density, is tiled on to be measured that chooses with the template that has rubber blanket gently, and attention should be exposed test specimen surface gravel particle, with hairbrush the sticking normal sand that stays of test specimen side is swept gently.

(4) take by weighing the gross weight G of test specimen and surface standard sand thereof once more _Hi=1161.81g.

(5) calculate construction depth DS1 with following formula 1:

$\mathrm{DS}1=10\frac{G_{\mathrm{hi}}-G_{\mathrm{qi}}}{\mathrm{\ρ}\×S}$

ρ is the density of normal sand: 1.4334g/cm ³,

The surface area of S test specimen, unit: cm ²

In above results measured substitution formula, result of calculation DS1=0.47mm.

Wherein 0.3～0.6mm normal sand supplier provides.

Embodiment 2 permanance detect test

Step 1. is selected a marshal piece of making, and the cooling back is with the method for step 2 among the embodiment 1 and the construction depth DS=0.47mm of a bottom surface of condition detection test specimen.

Step 2. is packed test specimen in the special mould, is placed in the rut die trial, notes: with the one side that detects construction depth in the step 1 upwards as end face, so that carry out the rut abrasion test;

Step 3. is placed on test specimen and mould and is incubated 6～8 backs in 60 ℃ the environment and under 60 ℃, carries out the rut abrasion test, tests the technical requirement, load level, travelling speed etc. of the used wheel requirement according to present asphalt rut experiment standard; The number of times of rut abrasion test is 3000 times

After step 4. off-test, test specimen is taken out from mould, test specimen is cut into a rectangular parallelepiped test specimen along the vestige of rut;

After step 5. is thoroughly dried the rectangular parallelepiped test specimen, place in 20 ± 2 ℃ the environment, behind the insulation 6h, carry out subsequent operation under the identical temperature:

1) measure the length and the width of rectangle test specimen end face, each is measured three times, averages to be length 86.64mm and width 48.91mm, and the surface area S ' of calculation testing piece is to take by weighing weight G ' simultaneously ₁=619.98g.

2). with the normal sand of 0.3～0.6mm of known density, pull the wheel path end face of the rectangular test specimen that is tiled in well cutting gently with the mould that has rubber blanket, attention should be exposed test specimen surface gravel particle.Take by weighing the weight of test specimen this moment, comprise the weight G ' of test specimen end face normal sand ₂=622.54g;

3). the construction depth DS ' after the abrasion of calculation testing piece rut:

${\mathrm{DS}}^{,}=10\frac{D_2^{\′}-G_1^{\′}}{\mathrm{\ρ}\×S^{\′}}=0.42\mathrm{mm}$

ρ is the density of normal sand: 1.4334g/cm ³,

The surface area of S test specimen, unit: cm ²

4) calculate the remaining rate of construction depth $\mathrm{\α}=\frac{{\mathrm{DS}}^{\′}}{\mathrm{DS}}=\frac{0.42}{0.47}=89.36\%.$

Permanance with α evaluation test asphalt.

Claims (8)

1. the indoor detection method of an asphalt mixture construction depth, its step is following:

(1). make test specimen,

(2). detect test specimen construction depth DS:

(a). the one side of choosing test specimen is to be measured, and survey area S is paved with normal sand,

(b). obtain the gross weight G of the normal sand of spreading,

(c). the construction depth DS of calculation testing piece:

$\mathrm{DS}=\frac{G}{\mathrm{\ρ}\×S},$ ρ is the density of normal sand.

2. the indoor detection method of an asphalt mixture construction depth permanance, its step is following:

(1) detection method of employing claim 1 detects the construction depth DS of test specimen,

(2) test specimen is carried out wheel tracking test in the one side of construction depth DS to be detected,

(3) treat test specimen cooling after, detect the construction depth DS ' of rut wheelmark part in the test specimen:

(a). measure the area S ' at wheelmark position, and partly spread normal sand at the rut wheelmark of test specimen,

(b). obtain the gross weight G ' of the normal sand of spreading,

(c). the construction depth DS ' of calculation testing piece:

${\mathrm{DS}}^{\′}=\frac{G^{\′}}{\mathrm{\ρ}\×S^{\′}},$ ρ is the density of normal sand,

(4) calculate remaining rate: the DS ' of construction depth/DS.

3. indoor detection method according to claim 2, before the construction depth step of rut wheelmark part, the test specimen with rut wheelmark part cuts down as part to be had a try earlier in the said detection test specimen.

4. indoor detection method according to claim 2 saidly carries out test specimen being placed 60 ℃ of insulations 6-8 hour before the wheel tracking test to test specimen, and under uniform temp, carries out wheel tracking test.

5. according to the described arbitrary indoor detection method of claim 1 to 4, during said detection construction depth step, test specimen is under 18-22 ℃, is incubated 6-8 hour.

6. according to the described arbitrary indoor detection method of claim 1 to 4, the said step of obtaining the normal sand weight of spreading is following:

A). its weight of weighing G after the test specimen drying ₁

B). take by weighing the gross weight G of test specimen and its surface standard sand ₂,

C). the weight of the normal sand of spreading is G ₂-G ₁

7. according to the described arbitrary indoor detection method of claim 1 to 4, the normal sand of the preferred 0.3～0.6mm of said normal sand.

8. according to the described arbitrary indoor detection method of claim 1 to 4, said making test specimen is to adopt marshall compaction forming method or gyratory compaction forming method, and the specification of said test specimen is the cylinder specimen of diameter 100mm to 150mm.