中国铁道科学
中國鐵道科學
중국철도과학
CHINA RAILWAY SCIENCE
2010年
2期
12-17
,共6页
方明镜%艾长发%邱延峻%魏永幸%章天扬
方明鏡%艾長髮%邱延峻%魏永倖%章天颺
방명경%애장발%구연준%위영행%장천양
无砟轨道%基床表层防水层%防水沥青混合料%级配类型%弯曲蠕变%低温抗裂性能
無砟軌道%基床錶層防水層%防水瀝青混閤料%級配類型%彎麯蠕變%低溫抗裂性能
무사궤도%기상표층방수층%방수력청혼합료%급배류형%만곡연변%저온항렬성능
Ballastless track%Impermeable layer on subgrade surface%Impermeable asphalt mixture%Grading type%Bending creep%Anti-cracking performance in low temperature
试验选用沥青用量分别为4%,5%,6%,7%和8%的砂粒式防水沥青混合料AC-5的上限级配、中值级配和下限级配3种级配类型,在温度为0℃条件下进行加载量分别为50,100和200 N的弯曲蠕变试验.试验结果表明:沥青用量超过约5%后,依靠提高沥青用量改善沥青混合料的低温抗裂性能效果甚微;加载量为100 N时,试件跨中弯曲蠕变速率大于加载量50和200 N所对应的弯曲蠕变速率;3种级配的沥青混合料弯曲蠕变速率为下限级配大于中值级配,中值级配大于上限级配.根据试验结果的综合分析并考虑低空隙率、高防渗性等技术要求,关于防水用砂粒式沥青混合料适宜的级配类型建议选用中值级配.
試驗選用瀝青用量分彆為4%,5%,6%,7%和8%的砂粒式防水瀝青混閤料AC-5的上限級配、中值級配和下限級配3種級配類型,在溫度為0℃條件下進行加載量分彆為50,100和200 N的彎麯蠕變試驗.試驗結果錶明:瀝青用量超過約5%後,依靠提高瀝青用量改善瀝青混閤料的低溫抗裂性能效果甚微;加載量為100 N時,試件跨中彎麯蠕變速率大于加載量50和200 N所對應的彎麯蠕變速率;3種級配的瀝青混閤料彎麯蠕變速率為下限級配大于中值級配,中值級配大于上限級配.根據試驗結果的綜閤分析併攷慮低空隙率、高防滲性等技術要求,關于防水用砂粒式瀝青混閤料適宜的級配類型建議選用中值級配.
시험선용력청용량분별위4%,5%,6%,7%화8%적사립식방수력청혼합료AC-5적상한급배、중치급배화하한급배3충급배류형,재온도위0℃조건하진행가재량분별위50,100화200 N적만곡연변시험.시험결과표명:력청용량초과약5%후,의고제고력청용량개선력청혼합료적저온항렬성능효과심미;가재량위100 N시,시건과중만곡연변속솔대우가재량50화200 N소대응적만곡연변속솔;3충급배적력청혼합료만곡연변속솔위하한급배대우중치급배,중치급배대우상한급배.근거시험결과적종합분석병고필저공극솔、고방삼성등기술요구,관우방수용사립식력청혼합료괄의적급배류형건의선용중치급배.
This paper analyzes the bending creep test in low temperature (0 ℃) under different loading (50, 100 and 200 N) by choosing AC-5 with three representative grading types (near to the upper limit, median and lower limit of the grading range in specification) and different asphalt contents (4%, 5%, 6%, 7% and 8%). The test results show that the effect to improve the anti-cracking performance of the asphalt mixture in low temperature is little by increasing the asphalt content especially when the asphalt content exceeds 5%. The bending creep rate in the middle of the beam span is larger under 100 N loading than that under 50 and 200 N. The bending creep rate of the specimens with three grading types near to the lower limit is larger when compared to those with design grading near to the median and the upper limit (smallest). As required by low air voids and high impermeability, it is suggested that the median limit grading type should be adopted for the granular impermeable asphalt.