Mixture Performance of Bitumen Modified with Cocamide Diethanolamide

Bituminous binders have been modified by using cocamide diethanolamide.The chemical material used in this study is used for the first-time on the purpose of modification of the bitumen.In addition to the conventional bitumen tests(penetration,softening point and ductility tests),adhesion and peeling tests(Vialit,Nicholson and California tests)were carried out on the bituminous binders which are modified with different ratios of cocamide diethanolamide.According to the results of the tests,the most appropriate additive ratio has been determined.Samples containing the reference bituminous binder and the bituminous binder modified with the most appropriate cocamide diethanolamide ratio were prepared using the superpave volumetric mix design method(SuperpaveTM).In accordance with standard method of test for resistance of compacted asphalt mixtures to moisture-induced damage(AASHTO T 283),the moisture susceptibility of prepared samples has been examined.In order to observe the changes in strength due to the temperature difference,prepared samples were subjected to the freeze-thawing test in accordance with standard test method for resistance of concrete to rapid freezing and thawing(ASTM C 666).

Investigation of effects of Cocamide Diethanolamide chemical on physical and rheological properties of bituminous binder

In this study,bituminous binder was modified with Cocamide Diethanolamide chemical,a non-ionic surfactant,and the physical and rheological properties of modified binders were investigated.In addition,Cocamide Diethanolamide has been used for the first time to modify bituminous binder,and this situation makes the study distinctive.Bituminous binder was modified more than once with the chemical by changing modification parameters and using certain additive ratios(1%,3%,and 5%).The effects of different modification parameters and chemical additive on modified samples were investigated with conventional bitumen tests(softening point,penetration,ductility)and Superpave tests(rotational viscometer,rolling thin film oven test,pressure aging vessel,dynamic shear rheometer,bending beam rheometer).In addition,the structural characteristics of the reference binder and modified samples were examined by X-ray diffraction,Fourier Transform Infrared Spectroscopy,scanning electron microscopy,and energy dispersive X-ray spectroscopy.The examinations showed that Cocamide Diethanolamide softens bituminous binder and lowers processing temperatures.In addition,compared to reference binder,rutting resistances of modified bituminous binders decreased with the increase of additive ratio.However,modification with Cocamide Diethanolamide increased the resistance to fatigue cracks and thermal cracks.

Effects of Nitrogen-Containing Biodegradation Enhancers on Sorption of n-Hexadecane in Soil-Water System

Effects of nitrogen-containing biodegradation enhancers(methyl diethanolamine oleate(MDEAO) and oleic diethanolamide(ODEA)) on the adsorption of n-hexadecane in soil were studied by laboratory batch experiments. The partition coefficients(K_d values) of n-hexadecane sorption in soil-water system and those partition coefficients normalized to organic matter(K_(oc) values) were both determined. The adsorption isotherm curve of n-hexadecane in soil-water system was plotted. The measured results demonstrated that K_(oc) values changed in the soil-water system with different enhancers but are relatively invariant for the soil at the same site. The K_d values rose with the increase of the organic matter content in different soil. The average values of K_(oc) in the soil-water system with MDEAO, ODEA,and blank soil were 0.412, 0.252,and 0.309, respectively. The critical micelle concentration of ODEA and MDEAO was 0.7 mg/L and 1.9 mg/L, respectively,denoting that the solubilization capacity of ODEA was much stronger than MDEAO in the soil-water system. Consequently,the adsorption of MDEAO onto the solid surface increased the organic matter content in soil,which could make it more effective in enhancing the n-hexadecane adsorption. On the contrary, ODEA could inhibit the adsorption of n-hexadecane because of its less adsorption rate onto the soil particle surface and higher concentration in the soil-water system. According to the correlation coefficients, it was found that both the Henry linear and the Freundlich nonlinear isotherm sorption models were fitted to the data very well, however the Freundlich model was better than the Henry model.