E. Shaffie

Rutting Performance of Hot Mix Asphalt Mixture Using Nanopolyacrylate Polymer Modifier

Rutting is a common pavement failure in road pavement. Rutting occurs mainly due to several factors including increasing of vehicles numbers, environmental conditions and also due to construction and design errors. As a consequence the service life of asphalt pavement is affected and will be decreased. Various researches reported that using different types of polymers in bitumen modification could be a solution to delay deterioration of asphalt pavement. The main purpose of the study was to investigate the effect of the NPA polymer modifier on the rutting behaviour of the asphalt mixtures through Superpave designed mixtures. . Two different types of dense graded Superpave HMA mix were developed consists of Control mix and nanopolyacrylate (NPA) mix. Results showed that all the mixes passed the Superpave volumetric properties criteria which indicate that these mixtures were good with respect to durability and flexibility. Furthermore there is a significant difference between Control mix and NPA mix in terms of rutting in which rut depth after 8000 passes for Control mix was 5.94 mm while for NPA mix was 2.98 mm. The results of this investigation indicated that the Rutting test result of NPA demonstrates 3% better resistance to rutting than those prepared using Control mix. This is due to the addition of NPA to the bitumen has certainly improved the bitumen properties significantly and hence increase the resistant to rutting of the asphalt mixture. Therefore, it can be concluded that NPA polymer is feasible to be used as asphalt modifier and has potential for improvement in the field of pavement material and construction in future.

Cooling time of porous asphalt pavement affecting compaction process due to various raining condition

While bright sunshine and warm temperatures make for the best paving weather, construction projects can get a bit rough in adverse weather conditions. In this case, porous asphalt is used on paving. Light sprinkles can usually be handled without any serious problems. Moderate rainfall events, on the other hand, will generally require the paving project to be postponed. Steady downpours will cool the porous asphalt mix and make proper compaction extremely difficult to obtain. For the viability of the project, contractors will always wait until the sky clears up. According to the JKR Specification 4(Clause 4.2.6.4), it clearly states that no pavement work should be done during rain. The rain is a cold medium where it will actually cools down everything that make contact with the water. Whereas, the mix porous asphalt (PA) is a hot medium. When these two elements combined, the surface and the PA will harden at a stage where it will not be well compacted. This will cause problems in the future. The test is conducted by pouring water onto the pavement(through raining simulation).Since the rain intensity can be determined by the size of the rain drops, the difference in the shower hole size is good enough to create different rain intensities to predict the PA cooling rate when it makes contact with water. These two variables will work as a comparison in this study between raining and no rain condition. As a result, whenever the water make a contact with the PA, the rates of cooling drops 98% from the normal rates of cooling of PA (without rain)giving the Time Available for Compaction (TAC) to be less than 60 seconds. This study may be a knowledge on how the rates of cooling work if the PA make contact with water. It can also be used as future reference on the study of cooling rates of porous pavement during raining condition.

Rutting performance of cold bituminous emulsion mixtures

Cold Bituminous Emulsion Mixture (CBEM) is an environmentally friendly alternative to hot mix asphalt (HMA) for road surfacing, due to its low energy requirements. However, CBEM has generally been perceived to be less superior in performance, compared to HMA. This paper details a laboratory study on the rutting performance of CBEM. The main objective of this study is to determine the Marshall properties of CBEM and to evaluate the rutting performance. The effect of cement in CBEM was also evaluated in this study. The specimens were prepared using Marshall Mix Design Method and rutting performance was evaluated using the Asphalt Pavement Analyzer (APA). Marshall Properties were analysed to confirm compliance with the PWD Malaysia’s specification requirements. The rutting performance for specimens with cement was also found to perform better than specimens without cement. It can be concluded that Cold Bituminous Emulsion Mixtures (CBEM) with cement is a viable alternative to Hot Mix Asphalt (HMA) as their Marshall Properties and performance obtained from this study meets the requirements of the specifications. It is recommended that further study be conducted on CBEM for other performance criteria such as moisture susceptibility and fatigue.Cold Bituminous Emulsion Mixture (CBEM) is an environmentally friendly alternative to hot mix asphalt (HMA) for road surfacing, due to its low energy requirements. However, CBEM has generally been perceived to be less superior in performance, compared to HMA. This paper details a laboratory study on the rutting performance of CBEM. The main objective of this study is to determine the Marshall properties of CBEM and to evaluate the rutting performance. The effect of cement in CBEM was also evaluated in this study. The specimens were prepared using Marshall Mix Design Method and rutting performance was evaluated using the Asphalt Pavement Analyzer (APA). Marshall Properties were analysed to confirm compliance with the PWD Malaysia’s specification requirements. The rutting performance for specimens with cement was also found to perform better than specimens without cement. It can be concluded that Cold Bituminous Emulsion Mixtures (CBEM) with cement is a viable alternative to Hot Mix Asphalt (HMA) as their M...

Rutting resistance of asphalt mixture with cup lumps modified binder

Rutting is the most common pavement distress in pavement structures which occurs mainly due to several factors such as increasing of traffic volume, climatic conditions and also due to construction design errors. This failure reduced the service life of the pavement, reduced driver safety and increase cost of maintenance. Polymer Modified Binder has been observed for a long time in improving asphalt pavement performance. Research shows that the use of polymer in bituminous mix not only improve the resistance to rutting but also increase the life span of the pavement. This research evaluates the physical properties and rutting performance of dense graded Superpave-designed HMA mix. Two different types of dense graded Superpave HMA mix were developed consists of unmodified binder mix (UMB) and cup lumps rubber (liquid form) modified binder mix (CLMB). Natural rubber polymer modified binder was prepared from addition of 8 percent of cup lumps into binder. Results showed that all the mixes passed the Superpave volumetric properties criteria which indicate that these mixtures were good with respect to durability and flexibility. Furthermore, rutting results from APA rutting test was determined to evaluate the performance of these mixtures. The rutting result of CLMB demonstrates better resistance to rutting than those prepared using UMB mix. Addition of cup lumps rubber in asphalt mixture was found to be significant, where the cup lumps rubber has certainly improves the binder properties and enhanced its rutting resistance due to greater elasticity offered by the cup lumps rubber particles. It shows that the use of cup lumps rubber can significantly reduce the rut depth of asphalt mixture by 41% compared to the minimum rut depth obtained for the UMB mix. Therefore, it can be concluded that the cup lumps rubber is suitable to be used as a modifier to modified binder in order to enhance the properties of the binder and thus improves the performance of asphalt mixes.

Marshall properties and rutting resistance of hot mix asphalt with variable reclaimed asphalt pavement (RAP) content

Hot mix recycling is the process in which reclaimed asphalt pavement (RAP) materials are combined with new materials to produce hot mix asphalt mixtures. This paper details a laboratory study in which the effects of different RAP contents were evaluated on the performance of hot recycled mixes. The objective of this study is to evaluate the rutting resistance of asphalt mixes containing different percentages of RAP. The Marshall mix design method was adopted in this study to determine the OBC for the asphalt mixes containing four aggregate combinations with RAP contents of 0% (control), 15%, 25% and 35%. Volumetric analysis was performed to ensure that the result is compliance with specification requirements. The resilient modulus test was performed to measure the stiffness of the mixes while the Hamburg wheel tracking test was used to evaluate the rutting performance of these mixes. The results obtained showed that there were no substantial differences in volumetric properties, stability values and stiffness properties between the control mix and recycle mixes. It can be concluded that recycled mixes performed as good as the performance of conventional Hot Mix Asphalt (HMA) in terms of resilient modulus and rutting.

Moisture-Induced Damage Evaluation of Nanopolymer-Modified Binder in Stone Mastic Asphalt (SMA) Mixtures

This paper presents laboratory investigation on mix design and moisture-induced damage performance of nanopolymer-modified asphalt binder SMA mixture. The effect of nanopolyacrylate (NP) in the mixture was investigated using Marshall mix design and modified Lottman test. Nanopolyacrylate polymer-modified binder was prepared with addition of 0–6 % NP polymer by weight into asphalt binder. Results of SMA14 mixture showed that all the volumetric properties of the mixtures passed the Marshall requirement, which indicates that these mixtures were good with respect to durability and flexibility. The ITS of NC2% and NC4% mixtures increased with an increase in percentage of NP but not as good as the conventional mixture, NC0% which is added with PG76 polymer-modified binder. However, NC6% mixture showed higher tensile strength compared to PG76 modified binder. Results of the moisture-induced damage showed that all the mixes passed the AASHTOT283 criteria with TSR values greater than 80 %. The results also showed that the optimum NP obtained is 6 % by weight of asphalt binder is the most effective and potential proportion to improve moisture-induced damage performance. Thus, addition of nanopolyacrylate polymer to the binder has significantly improved the cohesion as well as adhesion properties of the binder, and hence the performance of stripping.

Stripping Performance and Volumetric Properties Evaluation of Hot Mix Asphalt (HMA) Mix Design Using Natural Rubber Latex Polymer Modified Binder (NRMB)

Striping one of the most common pavement failure usually occurs in pavement structures. This failure reduced the service life of the pavement, reduced driver safety and increase cost of maintenance. Polymer modified binder has been conducted previously to find an alternative material in pavement construction that can be used as new improvement for asphalt mix design. This paper presents the stripping potential benefits of natural rubber (NR) for the asphalt mixtures used on pavement. This research evaluates the physical properties and stripping performance of dense graded Superpave-designed HMA mix. Two different types of dense graded Superpave HMA mix were developed consists of unmodified binder asphalt mix (UMB) and natural rubber polymer modified binder asphalt mix (NRMB). Natural rubber polymer modified binder was prepared from addition of 8 % of NR into asphalt binder. Stripping results from Modified Lottman test and Boiling Water test were determined to evaluate the performance of these mixtures. Results showed that all the mixes passed the Superpave volumetric properties criteria which indicate that these mixtures were good with respect to durability and flexibility. The Stripping result of NPMB demonstrates better resistance to stripping than those prepared using UMB mix. Addition of NR to the binder has certainly improved the binder properties significantly and hence increase the resistant to stripping of the asphalt mixture. The results also shows that the optimum NR obtained is 8 % by weight of asphalt binder is the most effective proportion that having potential to improve physical properties and the performance of polymer modified asphalt binder. Therefore, it can be concluded that the NR polymer is suitable to be used as a modifier to modified binder in order to enhance the properties of the binder and thus improves the performance of asphalt mixes.

Using Nanopolyacrylate and Nanocomposite as Binder Modifiers for Stone Mastic Asphalt (SMA)

This paper presents the potential benefits of using nanopolyacrylate (NP) and nanocomposite (NC) polymers as modified binders in SMA mixtures. The optimum binder content of the SMA control mix was designed using PG76 binder and Modified Lottman test (AASHTO T283) was used to determine the stripping performance. A total of six (6) SMA modified mix were prepared using NP and NC modified binder formulations at 2%, 4% and 6%. Results from tensile strength test showed that SMA-NC6 have the highest IDT (521kPa) followed by SMA-NP6 (511 kPa), SMA-Control (500 kPa), SMA-NC4 (449kPa), SMA-NC2 (403kPa) and SMA-NP2 (379kPa). The stripping test on both control and modified SMA mixtures showed that TSR values for all the mix pass the 80 percent limit which fulfils the AASTHO T283 standard requirement and are therefore least susceptible to stripping. Based on the tensile strength test results and stripping performance, it was found that the addition of NC and NP modified binder demonstrate great potential in SMA mixtures showing significantly improved cohesion as well as adhesion properties of the binder. The results from this study found that all the SMA mix are resistance to moisture damage which could sustain the load from vehicles and exposed to severe condition without large degradation of the structure.

Physical Properties of Modified Asphalt Binder with Nanopolyacrylate

Modification of asphalt binder using polymers has been increasingly used by our government to enhance the properties of bituminous mixes and to prolong the lifetime of roads in the face of increased traffic. This paper reports the procedure for determining the physical properties of asphalt binder using penetration grade binder of 80/100 with nanopolyacrylates (NPA). The asphalt binder was modified with different percentages of NPA (0, 2, 4, 6, 8 and 10 % by weight of asphalt binder) in order to determine the appropriate proportion of asphalt binder and NPA that can provide special potential in enhancing the properties and strength of the bituminous road to achieve the specifications required. Asphalt binder properties were evaluated in penetration, softening and penetration index. The results of this investigation indicated that the 6 % by weight of NPA in asphalt binder is the most effective proportion, having potential to improve physical properties of asphalt such as increasing softening point and decreasing the penetration and high penetration index. The results also demonstrate that the NPA binders outperformed conventional asphalt binder in term of engineering properties and it can be concluded that NPA polymer is feasible to be used as asphalt modifier and has potential for improvement in the field of pavement material and construction in future.

Physical properties of asphalt emulsion modified with natural rubber latex

Asphalt is an important material that has been used widely in road paving industry as a binder for aggregate. There are a lot of studies that have been conducted to modify asphalt for the preparation of hot mix asphalt (HMA). From the study, it is proven that polymer modified asphalt can improve asphalt performance. However, there are very few studies that focus on modification of asphalt emulsion that were used for cold mix asphalt (CMA). In this study, natural rubber latex was selected as a modifier to modify asphalt emulsion. Post blending method was used to prepare polymer modified asphalt emulsion. The addition of natural rubber latex (NRL) into the asphalt emulsion was made in a cylindrical flask that is equipped with a propeller with three variables: the amount of polymer, mixing time and blending velocity. From the result, it can be concluded that natural rubber latex can be used to improve the rheological properties of modified asphalt emulsion residue. The maximum useful amount of polymer that c...