泡沫沥青衰变方程与发泡特性评价

Foamed Bitumen Decay Equation and Bitumen Foaming Characteristics Evaluation

摘要:

目前常用膨胀率和半衰期指标来评价沥青的发泡特性,由于缺乏明确的数值评价标准,有时难以判断最佳发泡参数.比较了现有的4种衰变方程,选定了泡沫沥青衰变方程的基本形式,应用微分方法推导出实际最大膨胀率的通式,由泡沫沥青衰变的边界条件修正得到标准衰变方程,从能量角度出发定义了泡沫能量指标,通过积分给出了计算公式.对实际工程所用4种沥青的发泡试验数据进行分析,泡沫能量指标物理意义明确,量化了沥青的发泡特性,既可确定沥青的最佳发泡参数,又可评价不同沥青的发泡特性.

Abstract:

The expansion ratio and the halflife are usually utilized to evaluate the characteristics of foamed bitumen at present,but it’s hard to determine the optimum foaming parameters due to lack of definite numerical evaluation criteria.Therefore,an index is developed in this study to solve the problem.One of the existing decay equations is chosen as the basic form of the foamed bitumen decay equation.Then the general equation is derived by differential for the actual maximum expansion ratio,and a general decay equation is obtained with corrected boundary conditions of foamed bitumen decay.The foam energy index is defined from the view of energy,and the index formula is derived by integral.The foaming test data of four kinds of bitumen used in actual works are analyzed.The result shows that the foam energy index quantifies the bitumen foaming characteristics with a clear physical meaning,and it can be used to determine the optimum foaming parameters and evaluate the characteristics of different foamed bitumen.