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A Mechanical Model for Three-phase permanent deformation of Asphalt Mixture under Repeated Load

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Journal of Wuhan University of Technology(Materials Science) 2009年第6期24卷 1001-1003页

作者：赵永利 School of Transportation Southeast University

On basis of the Burgers model, a new model consisting of modified dashpot and Van Der Poel model was derived from rheological and viscoelastic theory. Subsequently, triaxial repeated load permanent deformation tests of AC16 asphalt mixtures were conducted to validate this new developed model. Parameters of new developed model were obtained by a nonlinear regression analysis of test data, and then permanent strains and flow number of each mixture were calculated. The experimental results prove that the new developed model can well describe three phases permanent deformation of asphalt mixture under repeated load and it can be used for pavement mechanical analysis and rutting prediction.

关键词： asphalt mixture permanent deformation three phases theory triaxial repeated load

New approach for calculating permanent deformation in asphalt pavement

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Journal of Harbin Institute of Technology(New Series) 2010年第5期17卷 711-715页

作者：谭忆秋陈凤晨柳浩苏新董泽蛟董雨明 School of Traffic Science and Engineering Harbin Institute of Technology China Airport Construction Corporation of CAAC Beijing Municipal Road and Bridge Building Material Group Co.LTD

A new approach using the Fiber Bragg Grating(FBG)sensor and viscoelastic model to monitor and analyze the internal strain and temperature of asphalt pavement is proposed.Some parameters including peak strain,temperature and loading time were calculated with the application of multi-dimensional sensors group.These parameters were incorporated with viscoelastic model of five units to evaluate the permanent deformation of pavement.An application example was conducted,and the results show that it is feasible to analyze and calculate the permanent deformation of pavement structures with FBG sensors.

关键词： fiber bragg grating sensors permanent deformation strain viscoelastic

Use of Unconventional Aggregates in Hot Mix Asphalt Concrete

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Journal of Civil Engineering and Architecture 2024年第1期18卷 30-37页

作者： Viktors Haritonovs Dept.of Roads and Bridges Riga Technical UniversityRigaLatvia

The study investigates use of dolomite sand waste as filler or/and sand material plus BOF steel slag as fine and coarse aggregate for design of high performance asphalt concrete.Both environmental and economic factors contribute to the growing need for the use of these materials in asphalt concrete pavements.This is particularly important for Latvia,where local crushed dolomite and sandstone does not fulfill the requirements for mineral aggregate in high and medium intensity asphalt pavements roads.Annually 100 to 200 thousand tons of steel slag aggregates are produced in Latvia.However,it has not been used extensively in asphalt pavement despite its high performance characteristics.Dolomite sand waste,which is byproduct of crushed dolomite production,is another widely available polydisperse by-product in Latvia.Its quantity has reached a million of tons and is rapidly increasing.This huge quantity of technological waste needs to be recycled with maximum efficiency.Various combinations of steel slag,dolomite sand waste and conventional aggregates were used to develop AC 11 asphalt concrete mixtures.The mix properties tests include resistance to permanent deformations(wheel tracking test,dynamic creep test)and fatigue resistance.Laboratory test results showed that asphalt concrete mixtures containing steel slag and local limestone in coarse portion and dolomite sand waste in sand and filler portions had high resistance to plastic deformations and good resistance to fatigue failure.

关键词： Steel slag dolomite sand waste permanent deformation creep test fatigue

Effect of Seasonal Variations on the Behavior of Flexible Pavements in Burkina Faso: Towards Alternating and Periodic Loading of Multi-Axle Heavy Goods Vehicles for Road Durability

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Journal of Materials Science and Chemical Engineering 2024年第6期12卷 24-42页

作者： Kokoro Kobori Doua Allain Gnabahou Bouto Kossi Imbga Laboratoire de Chimie Analytique de Physique Spatiale et Energtique Universit Norbert ZONGO Koudougou Burkina Faso Laboratoire dEnergie Thermique Renouvelable Universit Joseph KI-ZERBO Ouagadougou Burkina Faso

Bituminous materials are heat-sensitive, and their mechanical properties vary with temperature. This variation in properties is not without consequences on the performance of flexible road structures under the repeated passage of multi-axles. This study determines the influence of seasonal variations on the rate of permanent deformation, the rut depth of flexible pavements and the effect of alternating loading of heavy goods vehicles following the temperature variations on the durability of roads. Thus, an ambient and pavement surface temperature measurement was carried out in 2022. The temperature profile at different layers of the modelled pavement, the evaluation of deformation rates and rutting depth were determined using several models. The results show that the permanent deformation and rutting rates are higher at the level of the bituminous concrete layer than at the level of the asphalt gravel layer because the stresses decrease from the surface to the depth of the pavement. On the other hand, the variations in these rates, permanent deformations and ruts between the hot and so-called cold periods are more pronounced in the bitumen gravel than in bituminous concrete, showing that gravel bitumen is more sensitive to temperature variations than bituminous concrete despite its higher rigidity. Of these results, we suggested a periodic and alternating loading of the different types of heavy goods vehicles. These loads consist of fully applying the WAEMU standards with a tolerance of 15% during periods of high and low temperatures. This regulation has increased 2 to 3 times in the durability of roadways depending on the type of heavy goods vehicle.

关键词： Pavement Rutting permanent deformation Multi-Axle Seasonal

Refinement and estimation of asphalt flow number using partial load history

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第1期9卷 120-133页

作者： M.A.Dalhat Khaleel Al-Adham Hamad I.Al-Abdul Wahhab Arshad Jamal Department of Transportation and Traffic Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversityDammamSaudi Arabia Department of Civil and Environmental Engineering King Fahd University of Petroleum and MineralsDhahranSaudi Arabia

The effect of tertiary flow length on asphalt concrete(AC) flow number(FN) has been studied in this paper. The standard FN test(AASHTO T378) designated by American Association of State Highway and Transportation Officials(AASHTO) is currently among the widely adopted test for assessing the rutting performance of AC mixtures. The standard adopts the Fracken model(FM) for fitting the permanent deformation curve(PDC), prior to FN estimation. The FN was observed to vary as tertiary flow progresses. The FM, along with other PDC models(MFM-1 and MFM-2) obtained by modifying the FM, was utilized to analyze and minimized this variation. Variation of FN resulted because of mathematization of the PDC data. Instead of representing the actual initiating point of permanent shear deformation of the strain data, estimated values of FN were observed to indicate the inflection points of the fitted parent curve. As per standard FN range suggested by AASHTO T378, the observed variation in FN leads to the situation, where a single asphalt mix specimen can be regarded as appropriate for two different traffic levels, depending on the tertiary flow point at which the test is terminated. Supplementary steps in the FN estimation methods were proposed for refinement of FN values. For the refinement and further standardization of FN value and FN test respectively, FN:T(flow number to test duration ratio) has been recognized as the key and most simple solution. Two potential options for employing FN:T in the estimation of FN have also been highlighted. Several important correlations have been reported herein as well. Comparatively, MFM-1 was found to be more robust in FN:T curve utilization than MFM-2 and FM.

关键词： Road engineering HMA permanent deformation Flow number Francken model Tertiary flow

A geomechanics classification for the rating of railroad subgrade performance

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Railway Engineering Science 2022年第3期30卷 323-359页

作者： Antonio Gomes Correia Ana Ramos Department of Civil Engineering ISISEUniversity of MinhoGuimara˜esPortugal

The type of subgrade of a railroad foundation is vital to the overall performance of the track structure.With the train speed and tonnage increase,as well as environmental changes,the evaluation and influence of subgrade are even more paramount in the railroad track structure performance.A geomechanics classification for subgrade is proposed coupling the stiffness(resilient modulus)and permanent deformation behaviour evaluated by means of repeated triaxial loading tests.This classification covers from fine-to coarse-grained soils,grouped by UIC and ASTM.For this achievement,we first summarize the main models for estimating resilient modulus and permanent deformation,including the evaluation of their robustness and their sensitivity to mechanical and environmental parameters.This is followed by the procedure required to arrive at the geomechanical classification and rating,as well as a discussion of the influence of environmental factors.This work is the first attempt to obtain a new geomechanical classification that can be a useful tool in the evaluation and modelling of the foundation of railway structures.

关键词： Subgrade Resilient modulus permanent deformation Geomechanical classification

Rutting prediction models for flexible pavement structures: A review of historical and recent developments

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第3期8卷 315-338页

作者： Auinash Kumar Singh Jagdish Prasad Sahoo Department of Civil Engineering Indian Institute of Technology RoorkeeRoorkee 247667India Department of Civil Engineering Indian Institute of Technology KanpurKanpur 208016India

Rutting is the major distress mode in flexible pavements occurring due to the repeated movement of traffic loading. deformation in the pavements comprise of both recoverable(elastic) and irrecoverable(plastic) part. Overall deformation occurring in the flexible pavement system due to continuous vehicular movement is contributed from all the components of pavement. A number of empirical models have been proposed by several researchers for analysis and prediction of accumulated rutting in different components of pavement. The accumulated permanent strain has been expressed as the function of the number of load applications and deviator stress applications in most of the models proposed;however, factors such as stress state, moisture content, material type and environmental conditions also impose a significant influence on the permanent deformation characteristics of pavement materials under cyclic loading. In this article, a comprehensive review has been carried out covering every aspect of deformation related to distress occurring in pavements. Important rut models, modeling approaches and modern concepts in the rutting analysis of pavement structures have been presented. In addition to review, fallacy existing in the current design practices related to adaptation of stiffness parameters and negligence of shear strength aspect of subgrade soil has been also presented with the support of literatures.

关键词： Road engineering permanent deformation Rutting models Resilient modulus Shear strength

Stability and permanent displacements analysis of wasteland during earthquakes

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Acta Seismologica Sinica(English Edition) 2001年第2期14卷 216-224页

作者： KE Han Geotechnical Institute of Zhejiang University Hangzhou China

According to the results of experiments on the municipal solid waste (MSW), a series of formula are deduced to calculate the leachate free-faced headline curve. By means of static and dynamic finite element method (FEM), the stability of a wasteland during earthquakes is analyzed. It is demonstrated that the positions of the most dangerous sliding surfaces during earthquakes are fairly stable. Based on the above findings, this paper developed the New-mark method by increasing the precision to reckon the permanent deformation of wastelands during earthquakes. The method presented in the paper is not only of great importance to instruct the anti-seismic design of wasteland, but also valuable to the design of ordinary dams and embankments.

关键词： wasteland stability anti-seismic permanent deformation P315.9

Analysis of permanent deformations of railway embankments under repeated vehicle loadings in permafrost regions

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Research in Cold and Arid Regions 2015年第6期7卷 645-653页

作者： Wei Ma Tuo Chen State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Science

By large-scale dynamic tests carried out on a traditional sand-gravel embankment at the Beilu River section along the Qinghai-Tibet Railroad, we collected the acceleration waveforms close to the railway tracks when trains passed. The dynamic train loading was converted into an equivalent creep stress, using an equivalent static force method. Also, the creep equation of frozen soil was introduced according to the results of frozen soil rheological triaxial tests. A coupled creep model based on a time-hardening power function rule and the Druker-Prager yield and failure criterion was estab- lished to analyze the creep effects of a plain fill embankment under repeated train loads. The temperature field of the embankment in the permafrost area was set at the current geothermal conditions. As a result, the permanent deformation of the embankment under train loading was obtained, and the permanent deformation under the train loads to the total embankment deformation was also analyzed.

关键词： vehicle load permanent deformation creep effect permafrost regions