Pavement Systems Engineering

Table of Contents

1. Frontmatter

2. “Performance Evaluation of High Recycle Asphalt Pavement Content: A Comprehensive Analysis”

   Dudhwala Rinkal, Rajesh Gujar

   Abstract

   Reclaimed asphalt pavement (RAP) has become a viable and sustainable pavement recycling option. Pavement engineers are investigating a variety of technologies, including warm mix asphalt (WMA) technology and alternative materials, like reclaimed asphalt pavement (RAP), in the construction of pavements due to worries about global warming and environmental pollution, rising energy costs, and limited financial resources. Repurposing old asphalt materials, RAP presents a tempting proposition as the infrastructure sector grapples with cost-effective alternatives and environmental issues. It is possible to reduce the need for virgin materials and minimize waste disposal by careful processing and mixing RAP into fresh asphalt mixtures. The paper covers the material characterization of RAP materials, virgin aggregates, and VG-30 bitumen. Samples are made for many tests, such as Marshall stability, indirect tensile strength (ITS), and tensile strength ratio (TSR), and mix designs are created for the Marshall mix design process. Results suggest that the mechanical properties and durability characteristics of asphalt mixes are greatly impacted by the addition of a high RAP concentration. The study balances stability, air voids, voids in mineral aggregate (VMA), and voids filled with asphalt (VFA) to determine the ideal binder amount for each RAP percentage. All things considered, this study advances knowledge about sustainable pavement building techniques and lays the groundwork for the successful integration of RAP into asphalt mixes, opening the door to a more economical and ecologically conscious road construction industry.

3. Influence of Incineration Biomedical Waste Ash on the Characterization of Cement-Treated Road Bases

   Ramulu Gugulothu, Venkateswarlu Jajam, S. Shankar

   Abstract

   This study investigates the influence of incinerated biomedical waste ash (IBMWA) on the properties of cement-treated road base materials (CTRB). IBMWA, a by-product of high-temperature (850–1100 °C) incineration of biomedical waste, contains inorganic components that could potentially enhance or modify the characteristics of road construction materials when used as a partial replacement for cement. CTRB was prepared by replacing OPC with 0%, 20%, 40%, 60%, 80%, and 100% IBMWA in order to determine the recommended maximum dosage of IBMWA, without compromising its effectiveness. The laboratory performance of CTRB with IBMWA was assessed, which includes unconfined compressive strength (UCS), indirect tensile strength (IDTS), resilient modulus (MR), and wetting and drying (W-D) resistance. The research results demonstrated that the incorporation of IBMWA had a positive influence on the characterization of CTRB. The strength characteristics of CTRB containing IBMWA increased with an increase in curing time. However, the strength of CTRB decreased with the increase of IBMWA content. The 7 days UCS of CTRB containing 20% IBMWA met the specification of base course as set by IRC: 37–2018. Additionally, after 12 cycles of wetting and drying, considered mixtures exhibited weight loss below the thresholds established by IRC: 89–2018. The concentrations of heavy metals in these mixtures remained below the limit set by the United States Environmental Protection Agency (US EPA) standards. Thus, partially replacing OPC with IBMWA in CTRB can mitigate heavy metal leaching issues, with 20% IBMWA identified as the suggested maximum dosage for effective performance.

4. Investigation of Volumetric Properties of Recycled Mixtures with Waste Engine Oil as Rejuvenator: Emphasis on Cost Analysis

   Vishal Kumar, Praveen Aggarwal, Shobhit Jain

   Abstract

   In the pavement industry, the use of reclaimed asphalt pavement (RAP) material is increasing due to its cost-effectiveness. However, substituting RAP for virgin aggregates and binder can lead to poor workability and degraded overall performance of the pavement. To address these issues, rejuvenators are being employed. This study explores the effect of waste engine oil (WEO) as a rejuvenator on the volumetric properties of recycled mixtures (RMs) with different RAP contents in the direction of sustainable pavements. The study investigates the optimum dosages of WEO through Marshall stability criteria for different RAP contents. Additionally, a comprehensive cost analysis is performed to evaluate the cost of different mixtures and hot mix asphalt (HMA). Results indicate that the inclusion of RAP significantly affects the volumetric properties of bituminous mixtures, which can be restored using WEO. The optimal dosages of WEO exhibit the volumetric properties of different RMs similar to the properties of HMA or within the limits suggested by specifications. Furthermore, 12 to 29% of cost savings can be achieved associated with virgin and waste materials, their transportation, and production of bituminous mixture with using 20 to 50% RAP. This study highlights the role of WEO as a sustainable rejuvenator, enabling increased utilization of RAP.

5. Effect of RAP Fractionation on Stiffness Behavior of Cold Asphalt Mix

   Harish Nanda, Anjan Kumar Siddagangaiah

   Abstract

   This study investigates the impact of fractionating Reclaimed Asphalt Pavement (RAP) on the stiffness properties of cold asphalt mix (CAM). The RAP material was divided into fine (passing through 2.36 mm) and coarse (ranging from 19 mm to 2.36 mm) fractions, along with an unfractionated type. For each type of fractionation, four RAP dosage levels (25, 50, 75, 100%) were evaluated. CAM was prepared with the optimal emulsion content at an air void of 10 ± 1% for all 13 mix combinations. The Indirect Tensile Stiffness Modulus (ITSM) was conducted at three temperatures (15 ℃, 25 ℃, and 35 ℃) for all 13 mix combinations. The Indirect Tensile Strength (ITS) and Resilient Modulus (RM) tests were also conducted at 25℃. Based on the findings, ITSM of CAM dropped with temperature for all fractionations. Regardless of temperature, the ITSM increased with the dosage of RAP for all fractionations. Compared to coarse and unfractionated mixes, fine fractionated mixes showed a 31% and 30% reduction in stiffness, respectively. Tensile strength improved by 53% for the coarse fraction (at 100% RAP) and by 38% for the unfractionated mix (at 50% RAP), but there was no appreciable change when fine RAP was added up to 50%. The RM values improved by 24, 83, and 92% for fine, coarse, and unfractionated mixes at increasing RAP doses. This study recommends using coarse fractionation over unfractionated and fine-fractionation of RAP in CAM for better tensile strength and stiffness characteristics.

6. Study on Degradation of Natural Coir Geotextile and Its Performance Assessment Using Coating Materials

   Devika R. Nair, G. Archa, Jayita V. Mohan, R. Anil

   Abstract

   With features including improved drainage, soil stabilization, and erosion management, natural geotextiles have become essential components in the construction of roads. The incorporation of coir geotextile reinforcement has the potential to enhance the structural performance of pavements, extend their lifespan, and mitigate settlement issues caused by subgrade soil instability. One of the objectives of this study is to evaluate both fresh coir sample and already laid coir geotextile sample from 2 different study areas chosen at Thiruvananthapuram, Kerala, through laboratory testing using Scanning Electron Microscopy (SEM). The second objective is to investigate the potential for enhancing geotextile performance through the application of different coatings: used cooking oil, paint, and bitumen, each offering unique properties and benefits. Even though the coir geotextile is said to have a life span of five years, from the study it was seen that the coir geotextile which was laid in the road for almost 12 and 18 months, was severely degraded. SEM analysis showed large cracks and pores in coir geotextile, which promoted the water absorption and thus degradation. Thus, to improve the lifespan, the coir geotextile was coated with three materials. The findings revealed that used cooking oil and paint showed inconsistent performance and limited effectiveness as a coating material. Bitumen emerged as more reliable option for improving the performance of coir geotextiles. Improved understanding of how coatings influence geotextile performance can lead to more sustainable construction practices, resulting in cost savings, enhanced structural integrity, and prolonged service life for transportation infrastructure.

7. Assessment of Strength and Long-Term Durability Properties of Stabilized Granular Lateritic Soil for Use in Base and Sub-Base Layer of Pavement

   Samir Saurav, Sameer Sen, Sanjeev Sinha

   Abstract

   This study explores the potential of stabilized granular lateritic soil as a viable alternative to high-quality aggregates in pavement layers. Laboratory studies were carried out to thoroughly evaluate the strength and long-term durability qualities of stabilized lateritic soil with various cement contents. Notably, increasing the cement content to 3% resulted in a remarkable threefold increase in unconfined compression strength compared to untreated samples. Moreover, significant improvements were experimentally observed in soaked California Bearing Ratio and indirect tensile strength, highlighting the effectiveness of stabilization. Long-term durability was rigorously evaluated through wetting–drying (W-D) cycles, revealing that the stabilized soil met established performance criteria. This confirms its suitability for use in both low and high-volume road construction projects. These findings underscore the improved material performance achievable through proper stabilization techniques. In conjunction with existing literature, this study supports the ongoing research and development of cost-effective and durable road construction materials utilizing locally available resources. By leveraging stabilized lateritic soil, infrastructure projects can potentially reduce dependency on scarce high-quality aggregates, mitigate environmental impacts associated with aggregate mining and transport, and promote sustainable construction practices.

8. Effect of Waste Transformer Oil (WTO) and Waste Engine Oil (WEO) on the Performance of 100% RAP Mixes at Reduced Mixing Temperatures

   M. Surendranath, M. Sivakumar

   Abstract

   Using sustainable materials in pavement construction has become essential nowadays to conserve material resources. This paper discusses the effect of Waste Transformer Oil (WTO) and Waste Engine Oil (WEO) on the performance of 100% RAP mixes produced at reduced mixing temperatures and compaction efforts. The mixing temperatures selected in the study are 125, 135, 145, 155, and 165 °C. Compaction efforts selected are 75 and 50 blows. The rejuvenator dosages used are 0.5 and 1% by weight of RAP content. Marshall samples were cast and tested for Marshall stability and flow. Volumetric properties (air voids, VMA, and VFA) are also determined for all the samples. 0% oil dosage could satisfy all the Marshall properties at 125 °C at 75 blows. 0% oil dosage at 155 and 165 °C and 0.5% WEO dosage at 135 °C could satisfy all the Marshall properties at 50 blows. It is concluded from the results that adding WEO at 0.5% dosage improves the workability of the mix, leading to better compaction, and helps in producing mixes at reduced temperatures and compaction effort. 100% RAP mixes can be produced at reduced mixing temperatures and compaction efforts with WEO as the rejuvenator. Testing of RAP mixes by adding fresh aggregates with or without a fresh binder may be tried to check the effectiveness of WTO as a rejuvenator for the future scope of the work. Performance-based testing of 100% RAP mixes may also be tried as the future scope of work.

9. Evaluation of Rheological Master Curve Models for Rice Husk Ash-Modified Asphalt: Goodness of Fit Approach

   K. Bhavinlal, Veena Venudharan

   Abstract

   Master curve, a tool for predicting and characterizing asphalt’s rheology, utilizes master curve models. The accuracy of a master curve model varies when neat asphalt is modified, attributed to the changes in the rheology, which necessitate the selection of an appropriate master curve fitting model for modified asphalts. In this direction, an effort was carried out in this research work to analyse the reliability and accuracy of two popular rheological models, the Christensen Anderson (CA) model and the sigmoidal model for Rice Husk Ash Modified Asphalt (RMA), through statistical goodness of fit indicators. In order to arrive at this objective, rheological characterization of RMA was carried out by performing temperature and frequency sweep tests. Shift factors were determined using the Williams–Landel–Ferry equation, and master curves for the complex modulus of the binders were developed. Further, a detailed goodness-of-fit analysis was carried out on the CA and sigmoidal model fitting techniques. The research results showcased that both models exhibit lower accuracy at high temperatures compared to intermediate and low temperatures. When comparing the precision of the models, the sigmoidal model exhibits greater accuracy than the CA model. However, the rate of error accumulation with the increase in RHA dosage is higher in the sigmoidal model in comparison with the CA model. Overall, it can be concluded that RHA modification significantly influenced the performance of the CA and sigmoidal models.

10. Machine Learning-Enhanced Soil Stabilization Using Multiwalled Carbon Nanotubes and Fly Ash for Road Construction

    Anish Kumar, Sanjeev Sinha, Sameer Sen

    Abstract

    This study investigates the effects of multi-walled carbon nanotubes (MWCNTs) on the engineering properties of soil-fly ash mixes, with a focus on enhancing California Bearing Ratio (CBR) for potential use as subgrade material in pavement construction. Soil-fly ash mixes were treated with various concentrations of MWCNT, SHMP (Sodium Hexametaphosphate), and cement. An optimal model and an alternative model were developed using CART regression analysis, with R² values of 0.95 and 0.84 for training and testing of the optimal model, respectively. A 13-node CART model was selected over a 26-node model to balance predictive accuracy and interpretability. The maximum CBR value observed was 50.78% for a mix of 0.01% MWCNT, 2% SHMP, and 3% cement (20% soil replacement with fly ash), compared to a minimum CBR of 4.39% for untreated natural soil. The findings suggest that adding MWCNT and cement to soil-fly ash mixes significantly enhances CBR, supporting the use of these stabilized materials for developing resilient subgrade layers.

11. Comparison of Structural Performance of Low Volume Roads in Kerala Using Falling Weight Deflectometer

    V. P. Sreenaja, R. Anil

    Abstract

    The study aims to evaluate the structural adequacy of Low-Volume Roads (LVRs) in Kerala using the Falling Weight Deflectometer (FWD). The analysis of pavement deflection data involves a back-calculation process, where pavement layer moduli are derived from deflection values obtained via FWD. This process utilizes specialized software and customized programming. Specifically, the KGPBACK software package is adopted for back-calculation, and a Python program is employed to perform back-calculation using the BISAR (Bitumen Stress Analysis in Roads) method in MATLAB. For this study, LVRs with a surface type of Open Graded Premix Carpet (OGPC) and Bituminous Concrete of thickness 40 mm (BC-40) are selected. These roads are constructed directly above a granular layer and have a thin bituminous surface layer. Estimating the remaining life of LVRs involves evaluating their current condition and predicting future performance under anticipated traffic loads and environmental conditions. The remaining life in the base year has been estimated in accordance with IRC: 115-2014 and IRC: 37-2018, based on the rebound deflection obtained using FWD. The selected LVRs for the study are found to be safe against fatigue and rutting criteria. The back-calculated moduli using KGPBACK and the BISAR method reveal that pavement layer moduli can be accurately simulated by both methods. Furthermore, the BISAR method can be adopted as an alternative to KGPBACK software. The validated moduli values also provide a good model fit when comparing the deflection values.

12. Fatigue Life and Durability Analysis of Waste Glass-Enhanced Cold Bitumen Emulsion Mixtures

    Mohammad Iqbal Malik, Mohammad Shafi Mir, Bijayananda Mohanty, Rania Al-Nawasir

    Abstract

    The use of hot mix asphalt (HMA) and conventional aggregate in road construction has the unintended consequence of accelerating resource depletion, environmental impact, and the consumption of fossil fuels. Building pavement sustainably is essential to prevent this. One kind of Cold Mix Asphalt (CMA) that provides a sustainable route ahead is Cold Bitumen Emulsion Mixtures (CBEMs). Waste issues are addressed and flexible pavement development is promoted by using waste materials as fine aggregates in cold-mix asphalt. This study examines the mechanical performance of replacing virgin fine aggregate with Waste Glass (WG) at different percentages (0% to 100%, in 20% increments), with a focus on fatigue life and resistance to moisture damage. Up to 60% WG content in CBEM-WG mixes showed mechanical performance that was on par with that of conventional HMA and normal CBEM (NCBEM), increased continuously beyond 60% addition, and showed maximum performance at 100% dosage. Moisture damage resistance declines as WG concentration rises, but is at par with HMAA statistical analysis was done to show the feasibility and accuracy of using waste glass in place of virgin materials in terms of mechanical properties. The coefficient of determination R² > 0.9 for all criteria indicates a significant effect of waste glass addition on fatigue performance.

13. Review Article on the Effect of Wireless Charging System for EVs on Pavement

    Bimala Noatia, Ambika Kuity, Mokaddes Ali Ahmed

    Abstract

    Utilising electric vehicles (EVs) appears to be a viable way to create a road transportation system that is sustainable. Electrified road systems or eRoad systems are one of the many intriguing ideas under consideration at the moment. This engineering review article aims to offer key insights into the potential impacts of wireless EV charging systems on pavement performance and its broader implications for transportation infrastructure. The idea of inductive power transfer (IPT) technology is covered in detail in this review, highlighting the fundamental ideas behind it. While IPT-based eRoads for wireless charging of EVs offer significant technological advances, they also pose engineering challenges in terms of heat management, material compatibility, and structural performance. This study highlights the potential advantages and challenges of wireless EV charging along with its implications for pavement infrastructure. It also provides insights into both the promising efficiencies of IPT-based eRoads and the engineering risks associated with integrating these systems into roadway structures, such as thermal strain, fatigue, and load-induced deterioration. Understanding these impacts is essential for developing resilient eRoad designs that maintain structural integrity while accommodating emerging charging technologies. Also, recommendations have been made to focus more on prospective solutions for overall improvement in pavement performance.

14. Combine Effect of Sulphur-Chitin on Aging Susceptibility of Asphalt Binder

    Aditya Kumar Das, Mahabir Panda

    Abstract

    Modifying asphalt profoundly impacts the oxidation of asphalt, considering the performance characteristics for high and intermediate temperature conditions. Aging significantly impacts the inherent properties of asphalt concerning intermolecular properties, which are responsible for the service life of the asphalt mix. Thus, it is important to have a constructive understanding of the role of modifiers in asphalt aging behavior before consideration. Therefore, this present study utilizes a comprehensive laboratory approach to the aging behavior of asphalt and to understand the impact of chitin as a modifier. The aging behavior of chitin-modified asphalt was investigated using different aging indices concerning different physical, rheological, and chemical parameters, tested at high and intermediate temperatures. The investigated parameters inferred that the inclusion of chitin can enhance the resistance of base asphalt and can be more effective at high dosages of chitin.

15. Influence of GGBFS and Processed Coarse RAP in Pavement Quality Concrete

    Imran Wasil, Dinesh Ganvir, Tanuj Chopra, Manoj Kumar Singh

    Abstract

    Due to scarcity of virgin aggregates, the use of reclaimed asphalt pavement (RAP) as a substitute for natural aggregates has gained popularity. Despite the fact that RAP is recycled in asphalt pavement, there is still excess RAP, and its use in concrete pavements has expanded in recent years. According to a survey, 95 percent of India’s pavement is bituminous pavement. As a result, the maintenance and reconstruction of such pavements generate RAP, which can be reused in concrete pavements as well as surface course, base course, and subbase of flexible pavements. Various studies on the properties of reclaimed asphalt pavement and its optimal requirements for usage in concrete have been conducted throughout the years. In this study, a total of eight concrete mixes with various proportions of processed coarse RAP (20%, 40%, and 60%) and a fixed percentage (40%) of GGBFS with different proportions of processed coarse RAP were prepared to enhance the interfacial transition zone in PQC. A study of fresh properties like slump value; hardened properties like density; mechanical properties like compressive strength, split tensile strength, and flexural strength; durability properties such as abrasion resistance; and time-dependent properties such as shrinkage of PQC mixes was carried out in the present study. The new processing technique enhanced the properties of RAP inclusive PQC mixes and the strength of all the concrete mixes was above the design target strength. It was observed that there was a reduction of more than 60% in the binder content of RAP aggregates as a result of the processing of RAP. The partial replacement of cement by GGBFS also enhanced the properties of concrete mixes. However, with the increase in the percentage of replacement levels of RAP, the properties of concrete mixes were slightly reduced, but the reduction was much less. Based on the strength and durability properties of PQC, it was concluded that GGBFS with processed coarse RAP aggregate up to 40% can be used in pavement quality concrete (PQC). Hence, this study proves to be effective in the utilization of process RAP aggregates with GGBFS in PQC.

16. Study on Pavement Response Considering Actual Tire Contact Area on Flexible Pavements

    S. R. Aswathy, V. P. Sreenaja, R. Anil

    Abstract

    The conventional approach to designing flexible pavements relies heavily on practical experience and simplified two-dimensional computer analysis. However, there is a growing trend in the transition towards more advanced mechanistic design methods, which aim to overcome the limitations associated with stress, strain, and displacement predictions in pavement analysis. This study examines the critical implications of departing from a circular contact area assumption in pavement design, as the Layered Elastic Theory proposed. Accurate tire-pavement interaction is essential to evaluate the pavement damage caused by various tire configurations. Actual tire measurements in this study revealed substantial deviations between the assumed circular contact area and actual contact areas for dual axle with reductions of 3.4% and three-axle trucks with reductions of 5.6%, leading to concentrated loads on smaller surface areas. This concentration results in elevated stress levels on the pavement surface, increasing the risk of damage and fatigue failure. The study revealed that. The study also identifies increased strain values, indicating a greater likelihood of rutting. Finite Element Analysis (FEA) using Abaqus FEA software was used to analyze the pavement responses. The study recommends considering actual contact areas, highlighting the importance of precision in engineering calculations and paving the way for more resilient and sustainable transportation infrastructure.

17. Optimization of Factors Influencing Performance Properties of Bitumen Stabilized Materials Using Design of Experiment

    Rahul Kumar, Shivang Pandey, Umesh Chandra Sahoo

    Abstract

    Pavement construction sector is exploring the possibilities of using bitumen-stabilized material (BSM) due to its environmental benefits, cost-effectiveness, and convenience of application. Based on laboratory investigations, this study analyzes the effect of aggregate temperature (AT) and bitumen emulsion content (BEC) on the performance of BSM. The mix design parameters, including BEC and AT, were optimized using a central composite design (CCD) using the response surface methodology (RSM). Furthermore, additional experiments were performed to validate the optimum solution given by the model. The results indicate that the effect of AT on the mechanical and volumetric properties of BSM is more significant at lower BEC. Validation of the optimum design method showed that RSM optimization is a successful method for BSM mix design.

18. Physical and Rheological Properties of High-Float Emulsified Asphalt Residues for Chip Seal Applications

    Rahul Reddy Banapuram, Kaushikee Biswas, Kranthi K. Kuna

    Abstract

    Asphalt surface treatments using asphalt emulsions are widely used in the road industry for pavement preservation, with chip seal being particularly popular due to its low initial cost and ease of construction. High float asphalt emulsions (HFAE) have been developed as an alternative to traditional asphalt emulsions to mitigate common issues such as bleeding, draining, and aggregate chip loss associated with chip seals. Unlike traditional asphalt, residue from HFAE exhibits unique characteristics, traditionally assessed through float tests. This study investigates the behavior of HF emulsified asphalt residues using alternative physical and rheological tests. Visual flow and drain down experiments were conducted to evaluate asphalt's resistance to flow and draining, while a stress sweep test measured the viscosity of HF emulsified asphalt residue. The results showed that HFAE residue demonstrated significant resistance to flow and drain down. Rheological evaluation via the stress sweep test revealed that HFAE residue exhibits a yield stress nature not present in the original asphalt, contributing to its high float characteristics. Understanding how yield stress varies with the type or percentage of emulsifier used can provide valuable insights, enabling researchers to select appropriate HF emulsifiers based on specific field requirements.