پاسخ خستگي روسازي بتن آسفالتي نيمه گرم حاوي سنگدانه هاي سيليسي و آهكي اصلاح شده با افزودني نانو ماده ارگانوسيلان به روش انرژي تلف شده

Fatigue Response of Half-warm Asphalt Concrete Pavement Containing Silica and Calcareous Aggregates Modified with the Addition of Organosilane Nanomaterial by Wasted Energy Method

ﭼﮑﯿﺪه ﻣﻘﺎوﻣﺖ در ﺑﺮاﺑﺮ ﺧﺴﺘﮕﯽ ﯾﮑﯽ از ﻣﻬﻤﺘﺮﯾﻦ ﺧﺼﻮﺻﯿﺎت ﻣﺼﺎﻟﺢ آﺳﻔﺎﻟﺘﯽ ﻣﯽﺑﺎﺷﺪ ﮐﻪ در ﻃﺮاﺣﯽ روﺳﺎزي از اﻫﻤﯿﺖ وﯾﮋهاي ﺑﺮﺧﻮردار اﺳﺖ. روﺳﺎزي، ﺑﺎ ﮔﺬﺷﺖ زﻣﺎن، ﺑﻪ دﻟﯿﻞ ﻋﺒﻮر ﺑﺎرﻫﺎي ﺗﺮاﻓﯿﮑﯽ و ﻗﺮار ﮔﺮﻓﺘﻦ در ﻣﻌﺮض ﺷﺮاﯾﻂ ﻣﺨﺘﻠﻒ ﻣﺤﯿﻄﯽ، دﭼﺎر ﺧﺮاﺑﯽ ﻣﯽﺷﻮد. ﺗﺮكﻫﺎي ﻧﺎﺷﯽ از ﺧﺴﺘﮕﯽ در ﻻﯾﻪﻫﺎي آﺳﻔﺎﻟﺘﯽ ﺑﻪ ﻋﻨﻮان ﻣﻌﯿﺎري در روشﻫﺎي ﻃﺮاﺣﯽ ﭘﺬﯾﺮﻓﺘﻪ ﺷﺪه اﺳﺖ. آزﻣﺎﯾﺶﻫﺎي ﻣﺨﺘﻠﻔﯽ ﺑﺮاي ﻣﺪلﺳﺎزي آزﻣﺎﯾﺸﮕﺎﻫﯽ اﺳﺘﻔﺎده ﻣﯽﺷﻮد ﮐﻪ از ﻣﯿﺎن آنﻫﺎ آزﻣﺎﯾﺶ ﺗﯿﺮ ﺧﺴﺘﮕﯽ ﭼﻬﺎرﻧﻘﻄﻪاي ﺑﻬﺘﺮﯾﻦ ﺗﻄﺎﺑﻖ را ﺑﺎ ﺷﺮاﯾﻂ ﻣﯿﺪاﻧﯽ دارد. در اﯾﻦ ﻣﻄﺎﻟﻌﻪ، ﺗﺄﺛﯿﺮ اﻓﺰودﻧﯽ زاﯾﮑﻮﺗﺮم ﺑﺮ ﻋﻤﻠﮑﺮد ﺧﺴﺘﮕﯽ ﻣﺨﻠﻮطﻫﺎي آﺳﻔﺎﻟﺘﯽ ﻧﯿﻤﻪﮔﺮم ﻣﻮرد ارزﯾﺎﺑﯽ ﻗﺮار ﮔﺮﻓﺖ. ارزﯾﺎﺑﯽ ﻋﻤﺮ ﺧﺴﺘﮕﯽ ﺑﻪ روش اﻧﺮژي ﺗﻠﻒ ﺷﺪه و ارﺗﺒﺎط ﭘﺎراﻣﺘﺮﻫﺎي اﻧﺮژي و روش ﺳﻨﺘﯽ )ﮐﺎﻫﺶ 50 درﺻﺪي ﻣﺪول ﺳﻔﺘﯽ( از دﯾﮕﺮ اﻫﺪاف اﯾﻦ ﭘﮋوﻫﺶ اﺳﺖ. در اﯾﻦ ﻣﻄﺎﻟﻌﻪ، از دو ﻧﻮع ﻣﺼﺎﻟﺢ ﺳﻨﮕﯽ آﻫﮑﯽ و ﺳﯿﻠﯿﺴﯽ، ﻗﯿﺮ ﺧﺎﻟﺺ 60-70 و اﻓﺰودﻧﯽ زاﯾﮑﻮﺗﺮم ﺑﻪ ﻣﻘﺪار 0/1 درﺻﺪ ﻧﺴﺒﺖ وزﻧﯽ ﻗﯿﺮ اﺳﺘﻔﺎده ﺷﺪه اﺳﺖ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن ﻣﯽدﻫﺪ ﮐﻪ اﻓﺰودن 0/1 درﺻﺪ زاﯾﮑﻮﺗﺮم ﺑﺎﻋﺚ ﺑﻬﺒﻮد ﻋﻤﺮ ﺧﺴﺘﮕﯽ ﻣﺨﻠﻮطﻫﺎي آﺳﻔﺎﻟﺘﯽ ﻧﯿﻤﻪﮔﺮم ﺷﺪ. ﻣﺨﻠﻮطﻫﺎي ﺣﺎوي ﺳﻨﮕﺪاﻧﻪ آﻫﮑﯽ ﻧﺴﺒﺖ ﺑﻪ ﻣﺼﺎﻟﺢ ﺳﯿﻠﯿﺴﯽ ﻋﻤﻠﮑﺮد ﺑﻬﺘﺮي در ﺑﺮاﺑﺮ ﺧﺴﺘﮕﯽ داﺷﺘﻨﺪ. ﻫﻤﭽﻨﯿﻦ، ارﺗﺒﺎط ﺑﺴﯿﺎر ﺧﻮﺑﯽ ﻣﯿﺎن ﭘﺎراﻣﺘﺮﻫﺎي اﻧﺮژي و ﻋﻤﺮ ﺧﺴﺘﮕﯽ ﺑﻪدﺳﺖ آﻣﺪ. آزﻣﻮن ANOVA ﻓﺮﯾﺪﻣﻦ ﻧﺸﺎن داد ﮐﻪ ﺗﻔﺎوت ﻣﻌﻨﺎداري ﺑﯿﻦ ﭘﺎراﻣﺘﺮﻫﺎي ﺗﺸﺨﯿﺺ ﻋﻤﺮ ﺧﺴﺘﮕﯽ (Nf50، NS*N، NER)و PV مخلوط‌هاي مختلف وجود دارد.

Fatigue resistance is one of the key specifications of asphalt materials that is of paramount importance in pavement design. Over time, because of the passage of traffic loads as well as exposure to different environmental conditions, pavement is damaged. Fatigue cracks in asphalt layers are accepted as a criterion in design methods. A variety of tests is employed in laboratory modeling, among which the four-point fatigue test is the best-adapted one to field conditions. In the present study, the effect of zycotherm additive on fatigue function of half-warm mix asphalt was tested. Other objectives of this study include assessment of fatigue life by wasted energy method and the association between energy parameters and traditional method (50% decline in stiffness modulus). In the current study, two types of calcareous and silica stone materials and 60-70 pure bitumen besides zycotherm additive of 0.1% of the bitumen weight have been utilized. The results revealed the improved fatigue life of half-warm mix asphalt due to the addition of 0.1% zycotherm. Mixtures containing calcareous aggregates performed better against fatigue compared to silica aggregates. Moreover, there was a very good relation between energy parameters and fatigue life. The ANOVA test result show that there was significant difference between fatigue life (Nf50، NS*N، NER) and PV parameters.