This study aims to quantify the susceptibility of granular materials used in pavements to changes in moisture content and propose a correlation model to incorporate this susceptibility into seasonal analyses.The fines...This study aims to quantify the susceptibility of granular materials used in pavements to changes in moisture content and propose a correlation model to incorporate this susceptibility into seasonal analyses.The fines content and the percentage of fractured coarse aggregates were identified as direct indicators of the resilient modulus susceptibility to changes in water content.The results showed that the percentage of fractured coarse aggregates particles(FR)has a more significant impact on the resilient modulus(Er)of crushed granular materials used in pavement construction than the combined indicator of the fines content and sample volumetrics(nf).Crushed granular materials with a higher percentage of fractured coarse aggregates are relatively insensitive to changes in the degree of saturation,but become more sensitive as the fine fraction porosity decreases.An adjusted model was proposed based on the existing formulation,but considers a complex parameter to describe and adjust the sensitivity of base granular materials to variations in moisture content with respect to fabrication charac-teristics,fines content and volumetric properties.The model shows that the variation of Er values is below10%for fully crushed granular materials.However,it reaches approximately±12%for materials with 75%of crushed coarse aggregates andþ40%and-25%for materials with FR=50%.This model could help select good ag-gregates characteristics and adjust grain-size distribution for environments where significant moisture content variations can occur in the pavement system,such as in the Province of Quebec(Canada).As it is based on pa-rameters that can be easily determined or estimated,it also represents a valuable tool for detailed design and analysis that can consider material characteristics.展开更多
磷石膏作为固废材料存在严重的堆积问题,虽然将其应用于路面基层能有效提高利用率,但在这方面的应用仍不够广泛。基于此,制备了一种由煅烧磷石膏、水泥、石灰和磷石膏组成的无机结合料,用作路面基层材料。为了验证其用于路面基层的可行...磷石膏作为固废材料存在严重的堆积问题,虽然将其应用于路面基层能有效提高利用率,但在这方面的应用仍不够广泛。基于此,制备了一种由煅烧磷石膏、水泥、石灰和磷石膏组成的无机结合料,用作路面基层材料。为了验证其用于路面基层的可行性,进行了一系列室内试验,包括无侧限抗压试验、水稳试验、干缩试验、干湿循环试验和冻融循环试验,通过X射线衍射仪(X-ray diffractometer,XRD)和扫描电子显微镜(scanning electron microscope,SEM)进行微观分析,研究物质间相互作用的反应机理。结果表明:结合料中煅烧磷石膏、水泥、石灰、磷石膏的最优质量配合比为10∶7∶2∶81。此配合比能较大程度地利用磷石膏,且抗压强度、水稳性得到了较大的提升,干缩应变降低明显,具有较好的耐久性能;符合规范要求,为路面基层施工提供了一种既经济又环保的方案。展开更多
文摘This study aims to quantify the susceptibility of granular materials used in pavements to changes in moisture content and propose a correlation model to incorporate this susceptibility into seasonal analyses.The fines content and the percentage of fractured coarse aggregates were identified as direct indicators of the resilient modulus susceptibility to changes in water content.The results showed that the percentage of fractured coarse aggregates particles(FR)has a more significant impact on the resilient modulus(Er)of crushed granular materials used in pavement construction than the combined indicator of the fines content and sample volumetrics(nf).Crushed granular materials with a higher percentage of fractured coarse aggregates are relatively insensitive to changes in the degree of saturation,but become more sensitive as the fine fraction porosity decreases.An adjusted model was proposed based on the existing formulation,but considers a complex parameter to describe and adjust the sensitivity of base granular materials to variations in moisture content with respect to fabrication charac-teristics,fines content and volumetric properties.The model shows that the variation of Er values is below10%for fully crushed granular materials.However,it reaches approximately±12%for materials with 75%of crushed coarse aggregates andþ40%and-25%for materials with FR=50%.This model could help select good ag-gregates characteristics and adjust grain-size distribution for environments where significant moisture content variations can occur in the pavement system,such as in the Province of Quebec(Canada).As it is based on pa-rameters that can be easily determined or estimated,it also represents a valuable tool for detailed design and analysis that can consider material characteristics.
文摘磷石膏作为固废材料存在严重的堆积问题,虽然将其应用于路面基层能有效提高利用率,但在这方面的应用仍不够广泛。基于此,制备了一种由煅烧磷石膏、水泥、石灰和磷石膏组成的无机结合料,用作路面基层材料。为了验证其用于路面基层的可行性,进行了一系列室内试验,包括无侧限抗压试验、水稳试验、干缩试验、干湿循环试验和冻融循环试验,通过X射线衍射仪(X-ray diffractometer,XRD)和扫描电子显微镜(scanning electron microscope,SEM)进行微观分析,研究物质间相互作用的反应机理。结果表明:结合料中煅烧磷石膏、水泥、石灰、磷石膏的最优质量配合比为10∶7∶2∶81。此配合比能较大程度地利用磷石膏,且抗压强度、水稳性得到了较大的提升,干缩应变降低明显,具有较好的耐久性能;符合规范要求,为路面基层施工提供了一种既经济又环保的方案。
