Stone Matrix Asphalt(SMA)is a gap graded mix;characterized by higher proportion of coarse aggregate,lower proportion of middle size aggregate and higher proportion of mineral filler.In the present laboratory study,com...Stone Matrix Asphalt(SMA)is a gap graded mix;characterized by higher proportion of coarse aggregate,lower proportion of middle size aggregate and higher proportion of mineral filler.In the present laboratory study,commonly available one conventional VG 30 bitumen and another modified binder,namely CRMB 60 have been used along with a non-conventional natural fiber,namely coconut fiber which is abundantly available in India to provide improved engineering properties and at the same time preventing the usual draining of binder in SMA.The role of a particular binder and fiber with respect to their concentrations in the mix is studied for various engineering properties.Marshall procedure has been followed to determine the optimum binder and optimum fiber contents and also to study the relative advantages of fiber addition in the SMA mixtures.Thereafter,the engineering properties under both static as well as repeated load conditions and moisture susceptibility characteristics have been studied.It is observed that only a marginal 0.3%coconut fiber addition brings significant improvement in the engineering properties of SMA mixes.展开更多
It is a common practice to apply a tack coat usually in the form of bituminous emulsion over an existing bituminous surface before laying another bituminous layer.The boundary between these two consecutive bituminous ...It is a common practice to apply a tack coat usually in the form of bituminous emulsion over an existing bituminous surface before laying another bituminous layer.The boundary between these two consecutive bituminous layers is the layer interface and the pavement stress distribution is highly influenced by the adhesion conditions at this interface.Poor adhesion causes adverse effects on the structural strength of the pavement system.A number of premature failures such as slippage failure and delamination failures result thus defeating the construction objectives.In the absence of a standard method and apparatus to address this field problem,an attempt has been made in this study to develop a simple testing arrangement to be used in a laboratory to determine the interlayer bond strength.Normal Marshall procedure has been used to prepare the specimens consisting of two different types of bituminous materials in lower and upper part of the same specimen.It is observed within the scope of study that Cationic rapid setting(CRS-1)emulsion applied at 0.25 Kg/m^(2) offers the best results of interlayer bond strength.展开更多
文摘Stone Matrix Asphalt(SMA)is a gap graded mix;characterized by higher proportion of coarse aggregate,lower proportion of middle size aggregate and higher proportion of mineral filler.In the present laboratory study,commonly available one conventional VG 30 bitumen and another modified binder,namely CRMB 60 have been used along with a non-conventional natural fiber,namely coconut fiber which is abundantly available in India to provide improved engineering properties and at the same time preventing the usual draining of binder in SMA.The role of a particular binder and fiber with respect to their concentrations in the mix is studied for various engineering properties.Marshall procedure has been followed to determine the optimum binder and optimum fiber contents and also to study the relative advantages of fiber addition in the SMA mixtures.Thereafter,the engineering properties under both static as well as repeated load conditions and moisture susceptibility characteristics have been studied.It is observed that only a marginal 0.3%coconut fiber addition brings significant improvement in the engineering properties of SMA mixes.
基金grateful to Director and Head of the Department of Civil Engineering of National Institute of Technology,Rourkela,Odisha,India,769008 for their constant support in undertaking this work.The authors also acknowledge with thanks the support received from the laboratory staff namely,Shri S.C.Xess and Shri Hari Mohan Garnaik.
文摘It is a common practice to apply a tack coat usually in the form of bituminous emulsion over an existing bituminous surface before laying another bituminous layer.The boundary between these two consecutive bituminous layers is the layer interface and the pavement stress distribution is highly influenced by the adhesion conditions at this interface.Poor adhesion causes adverse effects on the structural strength of the pavement system.A number of premature failures such as slippage failure and delamination failures result thus defeating the construction objectives.In the absence of a standard method and apparatus to address this field problem,an attempt has been made in this study to develop a simple testing arrangement to be used in a laboratory to determine the interlayer bond strength.Normal Marshall procedure has been used to prepare the specimens consisting of two different types of bituminous materials in lower and upper part of the same specimen.It is observed within the scope of study that Cationic rapid setting(CRS-1)emulsion applied at 0.25 Kg/m^(2) offers the best results of interlayer bond strength.
