Arkansas State University
Civil Engineering
Rutting is the permanent deformation of pavement layers which can be accumulated over time due to traffic repetition. The study involved measuring the deformation of concrete block pavement. The sample dimension was 1 m width and 1.4... more
Rutting is the permanent deformation of pavement layers which can be accumulated
over time due to traffic repetition. The study involved measuring the deformation of
concrete block pavement. The sample dimension was 1 m width and 1.4 m length.
The jointing sand was mixed with Portland cement at 0%, 4%, 6% and 8%. The
concrete block dimension was 200 mm by 100 mm with a thickness of 80 mm. The
concrete blocks were laid on different longitudinal slopes of 0˚, 3˚, and 6˚. The
bedding sand thickness was 70 mm before compaction. Stretcher bond laying pattern
was used with a jointing width of 4 mm. Highway Accelerated Loading Instrument
(HALI) was used to apply a 10 kN axial load. The deformation was measured after
applying 50, 100, 500, and 1500 cycles. Photogrammetry targets were fixed on the
concrete block surface. The deformation or rutting, was measured by photogrammetry techniques which detect the movement of photogrammetry targets. The analysis was done by using Design and Analysis Experimental software and the 2 full factorial designs were chosen for the experiment design. The results show that the higher the percentage of Portland cement in jointing sand, the less rutting will occur. The slope grade does not have direct effect on the rutting of slope section
over time due to traffic repetition. The study involved measuring the deformation of
concrete block pavement. The sample dimension was 1 m width and 1.4 m length.
The jointing sand was mixed with Portland cement at 0%, 4%, 6% and 8%. The
concrete block dimension was 200 mm by 100 mm with a thickness of 80 mm. The
concrete blocks were laid on different longitudinal slopes of 0˚, 3˚, and 6˚. The
bedding sand thickness was 70 mm before compaction. Stretcher bond laying pattern
was used with a jointing width of 4 mm. Highway Accelerated Loading Instrument
(HALI) was used to apply a 10 kN axial load. The deformation was measured after
applying 50, 100, 500, and 1500 cycles. Photogrammetry targets were fixed on the
concrete block surface. The deformation or rutting, was measured by photogrammetry techniques which detect the movement of photogrammetry targets. The analysis was done by using Design and Analysis Experimental software and the 2 full factorial designs were chosen for the experiment design. The results show that the higher the percentage of Portland cement in jointing sand, the less rutting will occur. The slope grade does not have direct effect on the rutting of slope section
- by Fares Tarhuni
- •
Soft soils such as clay soils, mostly if they comprise swelling minerals may produce great damage to structures, particularly when these soils are exposed to wetting and drying situations. The geotechnical properties of soft soils could... more
Soft soils such as clay soils, mostly if they comprise swelling minerals may produce great damage to structures, particularly when these soils are exposed to wetting and drying situations. The geotechnical properties of soft soils could be enhanced by utilizing chemical additives. In this paper, granite waste dust was used to adjust the properties of clay soils. This paper investigates the effect of granite rock dust on the geotechnical properties of soft soil. The particle size distribution, Atterberg limits, compaction, California bearing ratio (CBR) and direct shear strength characteristics of the soil when blended with various percentages of granite dust were evaluated. The findings show a great increase in the maximum dry density, optimum water content, direct shear strength and CBR with increasing the amount of granite dust. The best results obtained for CBR values were when the soils mixed with 8% granite dust. Although these findings indicate great improvement in the geotech...
The properties of soil play a major effect on the design of road pavements. Thus, using waste materials to develop the characteristics of weak soil is being progressively necessary for industrial constructions. In past years, several... more
The properties of soil play a major effect on the design of road pavements. Thus, using waste materials to develop the characteristics of weak soil is being progressively necessary for industrial constructions. In past years, several pieces of research have been done to show the significance of these waste materials on the strength of the soil. This research aims to focus on the impact of granite powder on the behavior of the soil subjected to loading. Therefore, soils blended with several amounts of granite powder i.e. 4%, 8%, 12%, 16%, and 20% of the total weight were examined. The CBR, compaction and direct shear tests were executed to evaluate the performance of the untreated and treated soils. The findings proved that adding granite dust increased noticeably the shear strength, CBR and dry density of the soils. It was found that an addition of 8% granite dust to the natural soil yields the most appropriate results among other contents of granite dust. Hence, it is concluded tha...
Arkansas produces the most of the rice in the United States. About 20% of poddy is rice husk (RH), which is burnt under controlled conditions to produce rice rusk ash (RHA). The RHA is considered an environmental hazard and a significant... more
Arkansas produces the most of the rice in the United States. About 20% of poddy is rice husk (RH), which is burnt under controlled conditions to produce rice rusk ash (RHA). The RHA is considered an environmental hazard and a significant challenge for rice millers. However, RHA is rich in pozzolanic material, which is mainly silica. In this study, RHA is used to stabilize poor soils. Another commonly used stabilizer, hydrated lime (HL), has also been evaluated for comparison purposes. Thus, this study aimed to determine the optimum percentages of RHA, HL, or a combination of these two agents by evaluating selective physical, mechanical, and chemical properties of four subgrade soils (two from Arkansas and two from Oklahoma). Various amounts (by mass of soil) of RHA (3, 6, and 9%), HL (1, 3, and 5%), and RHA+HL have been utilized to know their optimum dosages. Routine tests including the Atterberg limits, Modified
proctor, pH, California Bearing Ratio (CBR), unconfined compressive strength (UCS), free swell, and one-direction shrinkage were conducted for untreated and treated soils. Further, scanning electron microscopy (SEM) with X-ray diffractometer tests were performed to evaluate the changes in microstructure due to stabilization. Treated soils show a significant improvement in UCS and CBR data. Additionally, the free swell test also indicates a reduced swelling of treated soils. The optimum dosages of RHA and HL were found to be 6% and 3%, respectively. When these two agents
were used together, a blend of 4%RHA and 1%HL was found to be the most effective in improving engineering properties The findings of this research can significantly benefit the construction industry in Arkansas by reducing costs associated with traditional soil stabilization methods and finding a sustainable and environmentally way of using RHA.
proctor, pH, California Bearing Ratio (CBR), unconfined compressive strength (UCS), free swell, and one-direction shrinkage were conducted for untreated and treated soils. Further, scanning electron microscopy (SEM) with X-ray diffractometer tests were performed to evaluate the changes in microstructure due to stabilization. Treated soils show a significant improvement in UCS and CBR data. Additionally, the free swell test also indicates a reduced swelling of treated soils. The optimum dosages of RHA and HL were found to be 6% and 3%, respectively. When these two agents
were used together, a blend of 4%RHA and 1%HL was found to be the most effective in improving engineering properties The findings of this research can significantly benefit the construction industry in Arkansas by reducing costs associated with traditional soil stabilization methods and finding a sustainable and environmentally way of using RHA.
The practice of using waste materials to modify the properties of poor soils has become increasingly important in geotechnical engineering. In recent years, much research has been devoted to the effect of this waste material on soil... more
The practice of using waste materials to modify the properties of poor soils has become increasingly important in geotechnical engineering. In recent years, much research has been devoted to the effect of this waste material on soil properties. This study aims to address the influence of marble dust powder on the performance of subgrade. Thus, soils mixed with different percentages of marble dust were tested. The CBR test and modified proctor have been used to evaluate the performance of the soils mixed with marble dust. The statistical analysis illustrated that marble dust significantly enhanced the properties of the soils. The study concludes that an addition of 10% of marble dust to untreated (control) soils yields the most satisfactory results among other percentages of marble dust. The study recommends the use of marble dust in geotechnical construction.
Traffic jams occur when a volume of traffic influx produces a demand for space more significant than the road allows. Numerical field data addressing vehicle counts and statistical computer simulations are vital tools in determining a... more
Traffic jams occur when a volume of traffic influx produces a demand for space more significant than the road allows. Numerical field data addressing vehicle counts and statistical computer simulations are vital tools in determining a road's serviceability and traffic level. Both have been utilized in this study. The primary objectives of this study are to conduct a comprehensive analysis of the traffic flow, measure the Level of Service (LOS), travel time, degree of saturation, delay time, and articulate a strategy to reduce traffic congestion at roundabouts. The study unequivocally concluded that the LOS at the eastern entrance is F level. The data on the number of vehicles that pass through the roundabout at the eastern entrance of Benghazi were recorded during the peak hours from (12:00 to 1:30) p.m. The mixed traffic stream was then converted to passenger car units (PCU) to be homogenously equivalent. The results of the systematic analysis of the gathered data indicate that the roundabout at Benghazi's eastern entrance requires further development to alleviate the dire traffic conditions. To run an accurate simulation, the existing road layout was surveyed using surveying instrumentation, and the results were used to build a model. Acceleration and deacceleration lanes were proposed to improve the roundabout performance and reduce congestion. Then, the roundabout expansion proposal was introduced into the simulation to study its effectiveness in reducing traffic jams. The data were analysed and tested using SIDRA software. The Level of Service at the roundabout's lanes showed tremendous improvement as the Level of Service varied from A to B levels compared to the current LOS level of F.
Traffic congestion has emerged as a crucial issue in urban cities, especially at signalized intersections, causing long queues, more travel times and environmental problems. The effectiveness of the road system is heavily dependent on... more
Traffic congestion has emerged as a crucial issue in
urban cities, especially at signalized intersections, causing long
queues, more travel times and environmental problems. The
effectiveness of the road system is heavily dependent on the
performance of signalized intersections. This research focuses on
the Al-Salmani signalized intersection in Benghazi city as a case
study to highlight the delay and level of service (LOS) issues
prevalent in Benghazi intersections. The intersection holds
considerable importance within the traffic system of Benghazi city
due to its strategic location at the eastern entrance, adjacent to the
city center. The aim of this paper is to optimize traffic operations
in Al-Salmani signalized intersection by examining three proposed
scenarios including modifications in cycle length, heavy vehicle
restriction and additional lane construction. Synchro 11
simulation software is used to evaluate and improve the delay and
LOS at the intersection. The result of this study indicates that the
intersection is operating under the unsuitable condition with LOS
(F). Furthermore, the results highlighted that the second and third
scenarios showed significant reductions in delay and LOS. The
reduction in delay is more evidenced in scenario 3 with an
improvement in LOS from F to B.
urban cities, especially at signalized intersections, causing long
queues, more travel times and environmental problems. The
effectiveness of the road system is heavily dependent on the
performance of signalized intersections. This research focuses on
the Al-Salmani signalized intersection in Benghazi city as a case
study to highlight the delay and level of service (LOS) issues
prevalent in Benghazi intersections. The intersection holds
considerable importance within the traffic system of Benghazi city
due to its strategic location at the eastern entrance, adjacent to the
city center. The aim of this paper is to optimize traffic operations
in Al-Salmani signalized intersection by examining three proposed
scenarios including modifications in cycle length, heavy vehicle
restriction and additional lane construction. Synchro 11
simulation software is used to evaluate and improve the delay and
LOS at the intersection. The result of this study indicates that the
intersection is operating under the unsuitable condition with LOS
(F). Furthermore, the results highlighted that the second and third
scenarios showed significant reductions in delay and LOS. The
reduction in delay is more evidenced in scenario 3 with an
improvement in LOS from F to B.
Styrene-butadiene rubber (SBR) latex is used widely to increase the low-temperature resistance of asphalt binders. However, the high content of butadiene copolymer in SBR-treated asphalt causes oxidation and aging. Furthermore,... more
Styrene-butadiene rubber (SBR) latex is used widely to increase the low-temperature resistance of
asphalt binders. However, the high content of butadiene copolymer in SBR-treated asphalt causes
oxidation and aging. Furthermore, following the SBR modification, the compatibility and thermal
storage stability of SBR-modified asphalt is not satisfactory. Therefore, the best approach to
improve the quality of short-term aged SBR-modified asphalt is to lower the manufacturing
temperatures of the SBR-modified asphalt mixture. In this study, to reduce the preparation
temperatures of SBR-modified asphalt mixes and improve their performance after short-term
aging, several additives i.e., waste engine oil (WEO), warm mix agent i.e., ZycoTherm, and
WEO/ZycoTherm combination (WEO+ZycoTherm) were selected. The rheological properties and
aging performance of binder samples were evaluated through the rational viscosity, dynamic
shear rheometer, bending beam rheometer and Fourier transform infrared spectroscopy tests. The
results showed that adding WEO together with ZycoTherm into an SBR-modified binder
contributed to reducing the compaction and mixing temperatures. The chemical analysis showed
that the three additives i.e., WEO, ZycoTherm, and ZycoTherm/WEO declined the aromaticity
and chemical aging indicators of aged SBR-modified binders. Furthermore, it was demonstrated
that both the ZycoTherm and WEO/ZycoTherm improved the asphalt resistance to rutting at
elevated temperatures in both conditions i.e., before and after short-term aging. In addition, the
findings revealed ZycoTherm /WEO compound yielded the best performance to improve the
minimal-temperature cracking resistance of the SBR-modified binder, resulting in lower short-
term aging temperatures. In summary, this study highlights the necessity of lowering prepara-tion
temperatures in asphalt mixes containing SBR to enhance binder resistance to rutting and
cracking and reduce susceptibility to oxidation during short-term aging.
asphalt binders. However, the high content of butadiene copolymer in SBR-treated asphalt causes
oxidation and aging. Furthermore, following the SBR modification, the compatibility and thermal
storage stability of SBR-modified asphalt is not satisfactory. Therefore, the best approach to
improve the quality of short-term aged SBR-modified asphalt is to lower the manufacturing
temperatures of the SBR-modified asphalt mixture. In this study, to reduce the preparation
temperatures of SBR-modified asphalt mixes and improve their performance after short-term
aging, several additives i.e., waste engine oil (WEO), warm mix agent i.e., ZycoTherm, and
WEO/ZycoTherm combination (WEO+ZycoTherm) were selected. The rheological properties and
aging performance of binder samples were evaluated through the rational viscosity, dynamic
shear rheometer, bending beam rheometer and Fourier transform infrared spectroscopy tests. The
results showed that adding WEO together with ZycoTherm into an SBR-modified binder
contributed to reducing the compaction and mixing temperatures. The chemical analysis showed
that the three additives i.e., WEO, ZycoTherm, and ZycoTherm/WEO declined the aromaticity
and chemical aging indicators of aged SBR-modified binders. Furthermore, it was demonstrated
that both the ZycoTherm and WEO/ZycoTherm improved the asphalt resistance to rutting at
elevated temperatures in both conditions i.e., before and after short-term aging. In addition, the
findings revealed ZycoTherm /WEO compound yielded the best performance to improve the
minimal-temperature cracking resistance of the SBR-modified binder, resulting in lower short-
term aging temperatures. In summary, this study highlights the necessity of lowering prepara-tion
temperatures in asphalt mixes containing SBR to enhance binder resistance to rutting and
cracking and reduce susceptibility to oxidation during short-term aging.
Traffic jams occur when a volume of traffic influx produces a demand for space more significant than the road allows. Numerical field data addressing vehicle counts and statistical computer simulations are vital tools in determining a... more
Traffic jams occur when a volume of traffic influx produces a demand for space more significant than the road allows. Numerical field data addressing vehicle counts and statistical computer simulations are vital tools in determining a road's serviceability and traffic level. Both have been utilized in this study. The primary objectives of this study are to conduct a comprehensive analysis of the traffic flow, measure the Level of Service (LOS), travel time, degree of saturation, delay time, and articulate a strategy to reduce traffic congestion at roundabouts. The study unequivocally concluded that the LOS at the eastern entrance is F level. The data on the number of vehicles that pass through the roundabout at the eastern entrance of Benghazi were recorded during the peak hours from (12:00 to 1:30) p.m. The mixed traffic stream was then converted to passenger car units (PCU) to be homogenously equivalent. The results of the systematic analysis of the gathered data indicate that the roundabout at Benghazi's eastern entrance requires further development to alleviate the dire traffic conditions. To run an accurate simulation, the existing road layout was surveyed using surveying instrumentation, and the results were used to build a model. Acceleration and deacceleration lanes were proposed to improve the roundabout performance and reduce congestion. Then, the roundabout expansion proposal was introduced into the simulation to study its effectiveness in reducing traffic jams. The data were analysed and tested using SIDRA software. The Level of Service at the roundabout's lanes showed tremendous improvement as the Level of Service varied from A to B levels compared to the current LOS level of F.
The future of Warm Mix Asphalt (WMA) technologies is promising in the U.S. However, the Arkansas Department of Transportation (ARDOT) does not have any specific guidelines to implement them in the field. This research aims to provide... more
The future of Warm Mix Asphalt (WMA) technologies is promising in the U.S. However, the Arkansas Department of Transportation (ARDOT) does not have any specific guidelines to implement them in the field. This research aims to provide necessary baseline data for WMA as a proof of concept. In this study, three ARDOT approved Performance Grade (PG) binders namely PG 64-22, PG 70-22, and PG 76-22 were investigated. Each of these binders was obtained from two different sources. They were modified by varying doses of four selected additives: Sasobit ® , Advera ® , Evotherm ® , and Rediset ®. Additionally, four different types of aggregates (sandstone, limestone, gravel, and dolomite) from different quarries in Arkansas were evaluated for their compatibility with modified binders. Empirical test (Penetration test), Superpave Performance tests such as Rotational Viscometer, Rolling Thin-Film Oven (RTFO), Pressure-Aging Vessel (PAV), Dynamic Shear Rheometer (DSR), and Bending Beam Rheometer), PG Plus tests such as Multiple Stress Creep Recovery and Frequency Sweep, chemical analyses (SARA analysis, FTIR, pH), science-based test (Surface Free Energy), and Texas Boiling Test on loose mixture samples were conducted at different aging conditions. Based on the RV test results, reduced mixing and compaction temperatures have been observed for Sasobit ® , Evotherm ® , and Rediset ® modified samples. The DSR test results suggest that both Sasobit ® and Advera ® can reduce rut potential. On the other hand, BBR test results indicate that both Evotherm ® and Rediset ® have the capabilities of improved resistances against fatigue and low-temperature thermal cracking. Binder samples modified by these have also demonstrated minimal stripping in SFE and Texas Boiling Test. Advera ® has modified the chemical compositions of the neat binders, which was also observed in the SARA analysis. The findings of this study will help the agency to select the most appropriate WMA additive along with its application rate.