Highway Pavement Research Articles

Study on the Effect of Regeneration Agent on the Viscosity Properties of Aged Asphalt.

China’s highway asphalt pavement has entered the stage of major repair, and improving the utilization rate of recycled asphalt pavement (RAP) is the main issue. The key link affecting the performance of recycled asphalt mixtures is the regeneration of aged asphalt, and the effect of the regenerant dosing on the high-temperature performance and viscosity of aged asphalt is the main content to be studied in this research. The aging behavior of asphalt seriously affects the roadworthiness of asphalt mixtures. In this study, we investigated the effect of changes in the microscopic properties of the aged asphalt on its viscosity properties during regeneration using gel permeation chromatography (GPC), Fourier-transform infrared spectroscopy (FTIR), and atomic force microscopy (AFM) as well as Brinell viscosity tests. This study simulated asphalt aging by the RTFOT test, and then we obtained an aged asphalt with a needle penetration of 30. We prepared different regenerated asphalts by adding regeneration agent with doses of 2%, 4%, and 6% to the aged asphalt. The results showed that the regeneration agent could effectively reduce the viscosity of the aged asphalt, which can play a positive role in improving the construction and ease of the aged asphalt. Rejuvenation agents affected the aging asphalt sulfoxide and carbon group indices. Moreover, rejuvenation agents can also significantly reduce the intensities of their characteristic functional group indices. The results of the AFM test showed that the increase in the dose of regeneration agent increased the number of the asphalt bee-like structures and decreased the area of individual bee-like structures. The results of the GPC test were consistent with the results of the AFM test, and the increase in the dose of regeneration agent reduced the asphalt macromolecule content. The viscosity properties and microstructure of the aged asphalt changed positively after the addition of the regeneration agent, indicating that the regeneration agent had a degrading and diluting effect on macromolecules.

Performance of cement-stabilized weak subgrade for highway embankment construction in Southeast Nigeria

Soils with poor shear strength and high compressibility underlie the wetlands of southern Nigeria. They are susceptible to intolerable settlements and account for greater than 60% of the soils in the region. While requiring embankments for any infrastructure construction, these weak soils pose significant threat to the construction and service life of highway pavements in southeastern Nigeria. Therefore, this research investigates shear strength improvement of a highway embankment’s weak subgrade soil after mass stabilization of soil with 6 and 10% Portland cement. The factor of safety against shear failure of the embankment was analyzed for un-stabilized subgrade and then cement-stabilized subgrade. The analysis was carried out for embankment heights of 4, 5, 6 and 7 m using the limit equilibrium method. Thick soft clayey silt with Cu range of 9 to 15 kPa underlay the embankment, upon improvement, the Cu of 154 and 208 kPa was obtained for 6 and 10% stabilization respectively. The FoS for the embankment on Un-stabilized soil ranged from 0.88 for a 7 m embankment to 1.2 for a 4 m embankment. The FoS after mass stabilization of 1 to 5 m soil ranged between 1.77 and 5.22 for the different embankment heights. Stability was better improved as depth of mass stabilization and cement content increased. A linear relationship was observed to exist between the cement content, strength of the improved soils, stabilization depth and the factor of safety.

Performance Decay Model and Preventive Maintenance of Highway Asphalt Pavement

This work aims to study the law of performance decay of highway asphalt pavement to facilitate preventive highway maintenance. By studying the performance decay law of asphalt pavement, this work proposes to optimize the Back Propagation Neural Network (BPNN) model with the Mind Evolutionary Algorithm, and apply the optimized model to the performance prediction of highway asphalt pavement. Some sections of Xi'an city are selected as sample data to train the neural network. A new type of asphalt material emulsified asphalt is proposed for pavement construction. Finally, the maintenance suggestions of asphalt pavement are given. The results show that the optimized BPNN model has a better fitting effect. The comprehensive evaluation indexes Root Mean Squared Error, Relative Root Mean Squared Error and Mean Absolute Error of the model prediction performance are lower than those of the model before optimization, and the decline rates are 62.46%, 62.46% and 62.71%, respectively. However, the values of Nash-Sutcliffe Efficiency and R2 increase by different degrees, with the increasing rates of 55.92% and 15.42%, respectively. It reveals that the optimized BPNN has more advantages in predicting road pavement performance, with higher accuracy and lower error rate. It provides a new idea for studying the maintenance of highway asphalt pavement. The performance of new asphalt materials is better than that of ordinary asphalt materials.

The Effect of Cow Dung Ash as A Filler on The Mechanical Characteristics of Hot Mix Asphalt

Highway pavements are being exposed to increasing traffic loads and severe environmental conditions, resulting in reduced service life. A lot of studies have been conducted to modify asphalt by using different materials, especially to replace the ordinary filler. Because the behaviour of the hot asphalt mix is influenced by the fillers. The use of unusual materials as fillers in asphalt mixes can help to improve the mix’s characteristics. As a result, this study uses cow dung ash materials with various replacement ratios as fillers to investigate the mechanical properties of asphalt. In the asphalt mix, a replacement percentage of limestone (0%, 10%, 20%, 30%, 40%, 50%, 60%, 80%, and 100%) was utilized. After that, various tests were performed such as Marshall stability, Marshall flow, voids in mineral aggregate, theoretical maximum specific gravity, air voids. The results revealed a significant improvement in the asphalt mix’s behaviour, as well as an increase in the replacement percentage. According to the findings, the 50% replacement rate has the highest Marshall stability which is equal to 11.11 with a 33.5% rise and the lowest flow of 3 with a 17.83% decrease when compared to the reference mix. As a result, cow dung ash can be used as a filler to modify the mechanical properties of the asphalt mix.

Strength and settlement of subgrade soil in southern part of Kangeyam block

Subgrade must typically be capable of supporting weights transmitted from the pavement or building structure. The relative compaction, optimum moisture content, and type of soil everything have an influence on bearing capacity. A good subgrade can withstand a large amount of loading without an excessive deformation. When subjected to heavy moisture or freezing temperatures, most soils experience some volume change. In case of pavement, highway pavements eventually rest on native soil, the subgrade serves as the foundation material for the pavement construction (subgrade). As a result, the features of subgrade have an impact on the performance of pavement. It is therefore critical for an engineer to comprehend the precise nature of the relationship between subgrade strength and settlement characteristics due tomoisture fluctuation. This paper represents that the soil sample taken in and around southern part of Kangeyam block (Kangeyam, Ganapathipalayam, Alangadu, Sampanthanpalayam, Sivanmalai, Periyailliyam, Padiyur, Veeranaampalayam, Vattamalai, Aratholuvu) was tested and experimented for its index and engineering properties. The index properties test includes specific gravity, sieve analysis, OMC (optimum moisture content) and MDD (maximum dry density) was conducted for classification of soil. Since the soil samples collected was predominantly identified sand of various gradation, the engineering properties test such as direct shear test was conducted to evaluate their shear strength properties. The subgrade strength of the soil samples was estimated by conducting CBR (California Bearing Ratio) test. In addition, the settlement of soil samples was evaluated as flexible pavement. The results of the tests data were entered in GIS (Geographical Information System) to describe the data as spatial representation mapping for the zone. This will ensure that the numerous subgrade qualities found throughout the zone are evaluated for safety and referred for future approaches.

Automated decision making in highway pavement preventive maintenance based on deep learning

Decision-making in highway preventive maintenance (PM) is generally costly and complicated. An inappropriate maintenance strategy could yield a low efficiency of budget usage and untreated road distress. This study describes an innovative predictive maintenance strategy that provides direct maintenance guidance to specific highway mileposts. This was achieved with the application of the artificial neural network (ANN) algorithm to mine a maintenance database. Ten-year distress measurement data at 100-m intervals, traffic load data, climatic history, and maintenance records of a chosen highway were regarded as the input data of the ANN model. A data quality control method was proposed to ensure asphalt pavement performance improvement continuity over time based on the idea of the maintenance year as the starting point for prediction. The backpropagation neural network (BPNN) model and a hybrid neural network (HNN) were applied to predict five indexes of the highway asphalt pavement performance, and the genetic algorithm (GA) was employed to optimize the hyperparameters of these models. The results indicate that the GA enhanced HNN model could increase the accuracy by 35% on average compared with traditional ANN in predicting the highway asphalt distress performance. Furthermore, a notable agreement is attained when comparing the predicted indexes to the whole-year measurement data invalidation with average coefficient of determination (R2) reaches 0.74. This study demonstrates the potential of an innovative ANN method in highway distress prediction to provide direct guidance for long-term highway asphalt pavement optimal rehabilitation and maintenance (R&M) decisions.

Effect of Temperature Fluctuations on the Bearing Capacity of Cold In-Depth Recycled Pavements

This study investigates the influence of the temperature fluctuations on the bearing capacity of cold in-depth recycled (CIR) pavements stabilized with foamed asphalt (FA). Aiming to achieve this goal, non-destructive testing was conducted during mild and high temperatures on a highway CIR pavement, utilizing mainly the FWD device. The back-calculated moduli values were utilized to estimate the strain values within the body of the pavement, while the strains induced using the FWD device were measured with a fiber optic sensors (FOS) system. Moreover, data from the fatigue behavior of the layer materials was also considered. The results of the related analysis indicate that for every 1 °C temperature increase within the body of the AC overlay, an approximately 5.7% increase of the critical tensile strain is expected. Moreover, for every 1 °C temperature increase within the body of the FA layer, an approximately 1.8% increase of the tensile strain at the bottom of the FA layer is expected. The new constructed layers, i.e., asphalt concrete (AC) and FA, sustain much more damage at high temperatures. This was more evident in the upper layer, i.e., the AC overlay.

POTENSI KEMBANG SUSUT TANAH EKSPANSIF DI WILAYAH SOLO RAYA (Studi Kasus di Trucuk, Pedan, dan Nogosari)

<p><em>Expansive soil has commonly found in several areas around infrastructure projects such as; highways, irrigation systems, buildings, and bridges. The behavior of expansive soils affects the strengths and durability of the upper structure. The main characteristic of expansive soil is the swell-shrinkage influenced by water content. Moreover, the negative trait harms the structure. For example, the cracks of the highway pavement and building wall and differential settlements in bridges abutment are the damage phenomena caused by expansive soil. The soil spread in several area near Surakarta residency namely Nogosari, Boyolali , Cawas Pedan, Klaten Regency, Bendosari Gentan, Sukoharjo and Purwodadi. Therefore, these areas have high vulnerability damage of Expansive soil. The study for determining and collecting data on the potential for shrinkage, which is a characteristic of expansive soil, is necessary conduct. This research aims to identify the swell-shrinkage potential in laboratory tests. The test had carried out with property index(water content and Atterberg limit) following code standards (SNI and ASTM). The liquid limit values </em><em></em><em>for the Trucuk, Padan, and Nogosari areas are 84.75%, respectively; 73.56% and 49.05%. The plasticity index values </em><em></em><em>for the Trucuk, Padan, and Nogosari regions are as follows: 66.97%; 45.72%; and 28.74%. A</em><em>ctivity </em><em>(AC) values </em><em></em><em>for the 3 Pedan, Trucuk, and Nogosari locations are as follows: 1.61; 1.67; and 1.28. The value results are based on laboratory tests output, were 3 locations in the Klaten area, namely Trucuk, Pedan, and Nogosari. In summary, the zones have high susceptibility area damage by expansive soil. The result of this study is expected to be preliminary mapping guidance surround the Surakarta Residency</em><strong></strong></p>

Investigation of premature failure mechanism in pavement overlay of national highway of Bangladesh

Roadway is the economic lifeline of Bangladesh. Maintenance of this roadway is main challenge of Roads and Highways Department (RHD). Overlay is the most common maintenance practice for National Highways, which design life is five years. However, it’s been reported, the overlay failed prematurely with cracking and rutting within one year even 6 to 9 months in some cases. This study aiming to investigate the premature failure mechanism of national highway pavement. Several field investigations were done on national highway namely N2. A numerical parametric study was also conducted with variable interfacial bond condition, overloading and layers stiffness. To investigate the pavements failures, conventional fatigue and rutting criteria were considered. Laser crack measurement system showed that alligator cracking is dominant failure mode followed by rutting. Alligator crack pattern indicated about slippage failure and overloading induced fatigue failure. Core cutting confirmed that interface de-bonding and cracking are strongly related. Bitumen samples were found highly temperature susceptible which could be correlated slippage failure. Moreover, Base layer stiffness variation was observed from Dynamic Cone Penetration test. Numerical analysis revealed that poor interfacial bonding significantly affects horizontal and vertical strain distributions; subsequently reduce pavement life but only it is not enough to fatigue and rutting failure of N2 within one year. Overloading found more significant than de-bonding especially for rutting. Analysis also suggested that fatigue and rutting failure within one year should be associated by coupling effect of poor bonding and overloading. Variation of base layer stiffness might be exacerbated the coupling effect in N2.

Optimisation method of network level pavement maintenance planning based on benefit maximisation subject to budget constraints and a case study

ABSTRACT Considering that the decision-making and planning of large-scale highway network under the condition of limited funds, there are some problems such as complex algorithm of feasible solution of maintenance scheme and low efficiency of optimisation process, a heuristic maintenance planning optimisation algorithm based on budget is introduced. This paper focuses on the performance prediction, the determination of treatment measures and the optimisation of the optimal scheme. Firstly, through the analysis of the technical process of prediction and treatment measures, the pavement performance degradation models of pavement condition index, riding quality index and rut depth index based on treatment level are established. Then, based on the characteristics of pavement performance degradation in China, the concept of maintenance benefit based on pavement performance index is proposed, and the cost-benefit optimisation model of highway asphalt pavement is established. A budget-based heuristic algorithm is proposed to solve the optimisation model for maintenance planning with budget constraints. Finally, taking Lian-Xu highway network in a case study, the optimal scheme of treatment measures and fund allocation for the maintenance section of the large-scale highway network is realised under the condition of limited funds, so as to verify the feasibility of the optimisation model.

Phyto-based sodium chloride hydrogel for highway winter maintenance of porous asphalt pavements

The need of the highway agencies to customize their winter maintenance operations on porous asphalt pavements prompted the authors to develop an innovative anti-icing technology based on the hot liquid spray application of a saline hydrogel. A bio-based (phyto-based) thermo-sensitive sodium chloride (NaCl) brine, that has the ability to form a gel simply by coming into contact with a very cold surface, was conceived. The increase in viscosity and the formation of a gel-like structure would make this anti-icing product able of filling the surface voids without permeating through the mixture (longer residual deicing effectiveness), while maintaining at the same time the pavement frictional resistance. In view of adopting sustainable winter maintenance strategies, this innovative blend was formulated by exploiting the thickening and gelling properties of wall-cell polysaccharides contained in seaweeds fibers. The mechanisms of gel formation were experimentally studied in laboratory, analyzing in detail the thermal and rheological properties of the salt hydrogel during the different phases of preparation, storage and application. On the basis of this characterization, a full-scale validation was carried out on an existing highway porous asphalt pavement. For this purpose, a tank truck prototype was equipped with a heating capacity tank and a customized specific spraying system.

Natural gravel-recycled aggregate concrete applied in rural highway pavement: Material properties and life cycle assessment

Natural gravel-recycled aggregate concrete (NG-RAC) has favorable prospects in rural highway pavement due to instant acceptance and tremendous need. This paper studies the material properties (including mechanical properties and frost resistance durability) and carries out a life cycle assessment (LCA) based on an actual engineering case. It can be found that, although the overall performance of NG-RAC is somewhat lower than those of natural aggregate concrete (NAC) or crushed stone-recycled aggregate concrete (CS-RAC), it meets the requirements for low-grade pavements. Compared with the pavement constructed with CS-NAC and CS-RAC, the results show that, carbon emissions are reduced by about 48.7% and 39.1% for the practical NG-RAC pavement, respectively. Besides, the sensitivity analysis of transport distance was conducted to estimate the limit transportation distance ratios of RCA/NCA and NG/CS. By quantitative analysis, it can be concluded that rural highway pavement built with NG-RAC will produce considerable environmental and ecological benefits, including energy-saving, carbon emission reduction, environmental cost lowering and land conservation.

Analysis on Soft Foundation Treatment Technology in Highway Subgrade and Pavement Design

Analysis on Soft Foundation Treatment Technology in Highway Subgrade and Pavement Design

Sustainable Improvement of Residual Lateritic Soils Using Alum

Cement stabilization has gained popularity in the tropics despite its known side effects. In Nigeria, a developing nation for instance, high cost and negative environmental impacts accompanying the use of cement constitute major drawbacks raising concerns. These shortcomings often make more sustainable alternatives necessary in a depressed economy. The current study explores the effects of alum on swelling potentials and strength of fine grained Nigerian lateritic soils with a view to ascertaining the viability of the additive as cost effective, eco friendly and sustainable substitute for improving engineering properties of the soils as highway embankment or pavement materials. Particle size analysis and Atterberg limits tests conducted according to British Standards (BS 1377) and ASTM D4318 respectively, aided in AASHTO classification of the un treated soils as A 6 (clayey soil), A 4 (silty soil) and A 7 5 (clayey soil). These are poor to fair subgrade materials requiring stabilization. Similarly, high amounts of fines in the natural soils suggest susceptibility to recurring shrink and swell during alternating dry and wet seasons typical of tropical regions. However, alum treated soils show reduction in plasticity with strong negative correlations. This implies reduction in swelling potentials and improvement in strength with alum treatment. Also, California bearing ratio (CBR) and shear strength, which followed the British Standards indicate strong positive correlations with alum content for the granite and charnockite derived soils. This indicates improved strength. Generally, the results suggest that alum has the potential to improve plastic fine grained lateritic soils in line with the Federal Ministry of Works and Housing general specification for roads and bridges, with combined engineering, economic and environmental benefits. Keywords: Additive, cement, embankment, highway, subgrade, soil stabilization, swelling soils DOI: 10.7176/JSTR/7-10-06

Permeability Analysis of Dredged Material and Its Stabilization Using Surkhi/Brick Dust

Abstract: This study presents the permeability and strong relationship of dredged soil stabilized with surkhi/brick dust which is to be used for constructing road embankments. Tests like the unconfined compressive strength test and the falling head permeability test were conducted. The test results showed that as the percentage replacement of surkhi increases, the samples become less permeable. Showing that the surkhi tends to cover up the pore spaces of the soil, causing the water to have fewer passageways. Large amount of sediments are dredged from rivers and lakes as a result of environmental dredging in India. These dredged materials (DM) have poor Geotechnical properties and are normally treated as wastes. On the other Hand, there is a huge demand of sub-grade materials due to the increasing number of highway construction projects in the J&K. Thus, the reuse of the dredged material as sub-grade material may be considered as an Environmental-friendly and economical option. For the stabilization of dredged material various waste materials can be effectively used. brick dust is one such waste product. The surkhi/brick dust is generated from brick kilns. The amount of brick dust produced every year is in the range of 3-4 million ton. This project therefore intends to study the stabilization of dredged material procured from Sindh Nallah having a higher content of alluvial Soil using Surkhi/Brick dust as an additive. Soil stabilization by this means can be utilized on airport pavements, highway pavements, earthen dams and many other situations where sub-soils are not suitable for construction. Keywords: dredged material Sindh Nallah, surkhi, Dredged soil, CBR, UCS, proctor test, porosity, void ratio and permeability

Research on Performance Prediction of Highway Asphalt Pavement Based on Grey–Markov Model

Reasonable and accurate forecasts can be used by the highway maintenance management department to determine the best maintenance timing and strategy, which can keep the highway performing well and maximize its social and economic benefits. A Grey–Markov combination model is established in this paper to predict highway pavement performance accurately based on the Grey GM (1, 1) model (a single-variable Grey prediction model with a first-order difference equation) and revised by the Markov model. The advantages of the short-term forecast Grey model and the probabilistic Markov model, which considers the fate of pavement performance prediction, are comprehensively applied to the combined forecasting model. The Grey GM (1, 1), Grey–Markov model and Liu-Yao model are adopted to predict the pavement condition index (PCI) based on the actual PCI values measured in Shanxi, Chongqing, and Shaoguan. The average relative errors of the above three models’ predicted values in Shanxi are 0.73%, 1.18%, and 0.67%, respectively, from 2012 to 2014. Thus, the prediction errors of the three models are relatively close. The average relative errors of the prediction values predicted by the three models are 3.89%, 0.67%, and 0.50%, respectively, from 2015 to 2019. The latter two errors are more minor than the Grey GM (1, 1) model. Two other regions have similar conclusions. The results show that the prediction accuracy of the combination Grey–Markov prediction model established in this paper is feasible to predict asphalt pavement performance in China.

Key Construction Techniques of Asphalt Mixture Paving in Highway Pavement Construction

Key Construction Techniques of Asphalt Mixture Paving in Highway Pavement Construction

A New Environmentally Friendly Utilization of Energy Piles into Geotechnical Engineering in Northern China

In the past 30 years, because of built-in advantages, energy saving, pollution control, and sustainability, the energy pile system has had a rapid development around the world. Many scholars did numerous researches on the parameters’ optimization, heat exchange efficiency, and structure-soil response. Also, the researches of evolutional GSHP system using high temperature in deep mine and lager collection surface of tunnel lining were learned. At present, most of researchers are discussing the geothermal collection for the heating or cooling the building, and plenteous and significant research achievements have been obtained. It is a novel attempt to apply energy pile to geotechnical engineering, and good results have been achieved in engineering practice in Northern China. The area of northern China is a typical seasonal frozen region: the high temperature in summer and the cold weather and accumulated snow in winter will result in huge challenge and resource consumption of maintaince on highway tunnel, pavement, and other geotechnical engineering facilities. In this paper, taking example of using the geothermal heat exchanger to melt snow, the novel idea of using energy piles to prevent track in summer and crack in winter of pavement, and guaranteeing the safety of frost crack on tunnel lining were discussed. Also, through simulation research, we propose a buried pipe form with good heat transfer uniformity-spiral buried pipe, which has better engineering applicability. This shows us that the application of energy pile in geotechnical engineering will provide solutions to geotechnical problems, which will have a brilliant future.

Analysis on Design Points of Highway Subgrade and Pavement Structure

Analysis on Design Points of Highway Subgrade and Pavement Structure

Data cleaning framework for highway asphalt pavement inspection data based on artificial neural networks

ABSTRACT The acquisition of high-quality asphalt pavement inspection data is a key factor for road maintenance and management throughout the pavement’s life cycle. This paper establishes a data cleaning framework that is based on data mining and deep learning to eliminate abnormal data points and interpolate missing points to improve the accuracy of the original road inspection dataset. The first process in the proposed framework is to analyse the influential factors that are used to evaluate data quality and calculate the abnormality of the data through the confidence interval used in Gaussian fitting. Then, a deep artificial neural network is established to learn the mapping between the inspection data and data abnormality. The abnormal points are removed according to their abnormality level. Next, a second deep artificial neural network predicts the missing point values. Finally, by defining the overall cleanliness index of the dataset as the optimisation target, the steps are repeated until the cleanliness threshold is met. In this study, the proposed framework was applied to rut depth data cleaning for a highway maintenance project in Jiangsu Province, China. The cleanliness of the rut depth data increased by 6–95.75% after one cleaning cycle.