Use of Lime as Anti-Strip Additive for Mitigating Moisture Susceptibility of Asphalt Mixes Containing Baghouse Fines PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Use of Lime as Anti-Strip Additive for Mitigating Moisture Susceptibility of Asphalt Mixes Containing Baghouse Fines PDF full book. Access full book title Use of Lime as Anti-Strip Additive for Mitigating Moisture Susceptibility of Asphalt Mixes Containing Baghouse Fines by . Download full books in PDF and EPUB format.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Recent NCDOT research suggests that baghouse fines with gradation similar to the natural and manufactured fines passing #200 sieve seems to have beneficial effect on stiffness and rutting characteristics of the asphalt mix. However, these studies conclude that mixes containing baghouse fines were highly moisture susceptible, and recommended that baghouse fines be metered into the mix to create a uniform percentage throughout the mix. This study assesses the effectiveness of hydrated lime as an anti-strip additive in mixes containing excess baghouse fines. Comparison of test results of the mixes containing hydrated lime versus the mixes containing organic anti-stripping additive (LOF 6500) was also done. Two different types of baghouse fines, one from Boone, NC and one from Enka, NC, were used in HMA mixtures in the amounts of 1.5, 5.5 and 6.5-percent. Modifications were made to the available JMF and specimens were prepared in the laboratory and several different tests were performed. Wet sieve analysis was first done to check the gradation of materials. Using this gradation and the available JMF, aggregate proportioning was done to satisfy NCDOT mix design criteria. Moisture susceptibility of mixes was determined by performing TSR tests on mixes with different proportions of BHF, and with or without lime. TSR testing showed that moisture susceptibility was dependant on both the concentration of baghouse fines and anti-strip additive. Presence of hydrated lime in mixes increased the resistance to moisture damage. Specimens were also tested using the SST machine. Samples were compacted and sawed and one half of the specimens were moisture conditioned. The FSCH and RSCH tests were then performed on the samples to determine the material properties as well as the rutting resistance and fatigue life. In general, the test results indicate that addition of lime enhances the mix performance - |G*| values are higher, rut depths are lower, and fatigue resistance is higher. Bas.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Recent NCDOT research suggests that baghouse fines with gradation similar to the natural and manufactured fines passing #200 sieve seems to have beneficial effect on stiffness and rutting characteristics of the asphalt mix. However, these studies conclude that mixes containing baghouse fines were highly moisture susceptible, and recommended that baghouse fines be metered into the mix to create a uniform percentage throughout the mix. This study assesses the effectiveness of hydrated lime as an anti-strip additive in mixes containing excess baghouse fines. Comparison of test results of the mixes containing hydrated lime versus the mixes containing organic anti-stripping additive (LOF 6500) was also done. Two different types of baghouse fines, one from Boone, NC and one from Enka, NC, were used in HMA mixtures in the amounts of 1.5, 5.5 and 6.5-percent. Modifications were made to the available JMF and specimens were prepared in the laboratory and several different tests were performed. Wet sieve analysis was first done to check the gradation of materials. Using this gradation and the available JMF, aggregate proportioning was done to satisfy NCDOT mix design criteria. Moisture susceptibility of mixes was determined by performing TSR tests on mixes with different proportions of BHF, and with or without lime. TSR testing showed that moisture susceptibility was dependant on both the concentration of baghouse fines and anti-strip additive. Presence of hydrated lime in mixes increased the resistance to moisture damage. Specimens were also tested using the SST machine. Samples were compacted and sawed and one half of the specimens were moisture conditioned. The FSCH and RSCH tests were then performed on the samples to determine the material properties as well as the rutting resistance and fatigue life. In general, the test results indicate that addition of lime enhances the mix performance - |G*| values are higher, rut depths are lower, and fatigue resistance is higher. Bas.
Author: Aniruddha Vilas Shidhore
Publisher:
ISBN:
Category :
Languages : en
Pages : 76
Get Book Here
Book Description
Keywords: moisture sensitivity, hydrated lime, mix performance, Baghouse fines.
Author: Bradley J. Putnam
Publisher:
ISBN:
Category : Asphalt
Languages : en
Pages : 178
Get Book Here
Book Description
The use of hydrated lime or other liquid anti stripping agents (ASA) is the most common method to improve the moisture susceptibility of asphalt mixes. However, most laboratory test conditions used to evaluate the moisture susceptibility of the mixes are only for a short duration of time. This might not be a good representation of the field conditions (i.e., several months or years of service). Thus, a study to evaluate the effects of conditioning the mixes for longer durations was initiated. Also, another problem with the use of the liquid anti stripping agents is their heat storage stability. This report addresses these two issues, by preparing and testing mixtures made with fresh binder for indirect tensile strength after conditioning the samples for 1, 7, 28, 90 and 180 days, and samples prepared from binder stored for three days at 160° C after conditioning them for 1, 28 and 90 days. The results of this study indicated that hydrated lime and the liquid anti stripping agents were equally effective for the mixes used in this research when conditioned beyond one day. In the case of samples prepared from stored binder, there was no significant difference in the effectiveness of hydrated lime and the liquid anti stripping agents even after conditioning for one day. Though it was observed that none of the ASA treatments performed better than others in the case of samples prepared with stored binder, it was also observed that almost all mixes gave significantly similar wet ITS and TSR values as samples prepared from fresh binder.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Moisture damage in asphalt pavement reduces the service life of the pavement as well as increase permanent deformation. Moisture sensitivity in asphalt concrete mixtures is often associated with high concentrations of fine aggregate particles. In this study, the effects of baghouse fines, a source of fine mineral aggregate, on moisture sensitivity were examined. Two types of baghouse fines with different gradations were used in various concentrations in the laboratory production of hot-mix-asphalt samples. To determine the effects of the various baghouse fines contents, testing was performed to determine the tensile-strength-ratio of the different mixes. In order to prevent moisture damage in asphalt pavements, additives are often used to alter the interaction between the asphalt binder and the mineral aggregate. These additives can change the molecular charge of the binder or reduce the viscosity of the asphalt cement. In order to determine the effectiveness of the anti-strip additive in preventing moisture damage, the tensile-strength-ratio was also determined for specimens containing various additive and baghouse fines contents. The results of the tests showed a reduction in retained strength for the specimens without additive as compared to the specimens containing additive, demonstrating the effectiveness of the additive in preventing moisture damage. To assess the rutting resistance of the various asphalt mixtures, an Asphalt Pavement Analyzer test was performed. Half of the laboratory compacted specimens were moisture conditioned and tested submerged, while the other half was tested dry. Results indicate an increase in rut depth with the removal of anti-strip additive from the mix, indicating the effectiveness of the additive in preventing moisture damage. Finally the specimens were tested in the Superpave Shear Test Machine. Frequency Sweep and Repeated Shear tests were performed for each mixture with half of the samples again conditioned. The Frequency Swee.
Author: JW. Button
Publisher:
ISBN:
Category : Additives
Languages : en
Pages : 13
Get Book Here
Book Description
Laboratory and field tests were conducted to evaluate the use of hydrated lime as an antistrip additive in hot mix asphalt concrete. Batch and drum mix plants were used to prepare the paving mixtures. Lime was added dry and in slurry form. Individual aggregates and the total aggregate were separately treated with lime slurry and allowed to age for different time periods from a few minutes to 30 days before mixing with asphalt. Laboratory mixed and plant mixed asphalt concrete was tested using indirect tension and resilient modulus before and after moisture conditioning. Results indicate that lime is effective in reducing moisture susceptibility and that it is most effective when applied in the presence of moisture. In addition, a time delay after application of lime to aggregate is unnecessary. There are no significant differences in mixtures produced in batch and drum plants.
Author:
Publisher:
ISBN:
Category : Pavements, Asphalt
Languages : en
Pages : 97
Get Book Here
Book Description
This project evaluated the influence of anti-strip additives on the durability and moisture susceptibility of granite-based open-graded friction course, referred to as FC-5 asphalt mixtures. The laboratory testing involved two granite-based FC-5 mixtures containing 1% hydrated lime (by weight of aggregate), 1% hydrated lime plus 0.5% liquid anti-strip (LAS) additive (by weight of asphalt binder), 1.5% hydrated lime, and 1.5% hydrated lime plus 0.5% LAS additive. Two sources of granite aggregates were obtained: one from Junction City, Georgia and the other from a regional supplier with an original source from Nova Scotia, Canada. Four types of LAS additives were collected from Road Science ArrMaz, Inc. and Ingevity, Inc. The binder bond strength test was used to select the LAS agents that provided the best improvement in moisture resistance. The FC-5 mixtures were fabricated in the laboratory using two FC-5 mix designs provided by the Florida Department of Transportation. The specimens were conditioned by the asphalt pavement weathering system to simulate the long-term aging and moisture conditioning in the field. Mixture performance tests, including the Cantabro test, tensile strength ratio test, and Hamburg wheel tracking test, were used to comprehensively evaluate the durability and moisture susceptibility of FC-5 mixtures. Finally, a cost-benefit analysis was performed to determine the cost-effectiveness of the FC-5 mixtures with anti-strip additives. This project found that the addition of LAS additive, extra 0.5% hydrated lime, or both produced longer lasting FC-5 mixtures, and the additional anti-strip additives would improve the cost effectiveness of FC-5 mixtures.
Author:
Publisher:
ISBN:
Category : Aggregates (Building materials)
Languages : en
Pages : 148
Get Book Here
Book Description
Author: G. W. Maupin
Publisher:
ISBN:
Category : Aggregates (Building materials)
Languages : en
Pages : 24
Get Book Here
Book Description
Stripping has long been recognized as a cause of asphalt pavement damage. Water may get between the asphalt film and the aggregate surface, causing an adhesive failure, or water may combine with the asphalt to affect the cohesive strength of the material. Various types of antistripping additives have been used in the attempt to alleviate or eliminate stripping. The Virginia Department of Transportation has used antistripping additives in some of its asphalt mixes since the 1960's. In the 1980's hydrated lime was found to outperform several al chemical additives. VDOT began to require asphalt contractors to use chemical additives that produced test results equal or superior to hydrated lime. Presumably, chemical additives were then improved to compete with hydrated lime. This study was undertaken to find if the new generation of additives prevented stripping in Virginia's hot mix asphalt. Twelve test sections were established, 9 using chemical additives and 3 containing hydrated lime. After 3 to 4 years, eight of the sections containing chemical additive demonstrated considerable visual stripping in cores. The sections containing hydrated lime showed much less stripping. The TSR test used on mix sampled during construction did not accurately predict the stripping that occurred. A follow-up survey of existing pavements should be conducted to verify the possible inadequacy of some chemical additives. Also, the TSR test should be examined and possibly modified to more closely duplicate Virginia's environmental conditions.
Author: David G. Tunnicliff
Publisher: Transportation Research Board
ISBN: 9780309053747
Category : Technology & Engineering
Languages : en
Pages : 68
Get Book Here
Book Description
Author: W. Virgil Ping
Publisher:
ISBN:
Category : Asphalt concrete
Languages : en
Pages : 646
Get Book Here
Book Description
This report summarizes the results of determining the moisture susceptibility by the primary test methods: (a) Original Lottman Method. (b) Modified Lottman Method (Tex-531-C); (c) Tunniclif f-Root Method; and (d) Boiling Test (Tex-530-C). Comparisons were made between the laboratory mixtures, plant mixtures, and cores obtained from the field test sections to determine the effectiveness of the various antistripping additives and to evaluate the various methods for measuring that effectiveness.
