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美国工程兵团的机场柔性路面设计通常根据两种方法,(a)加州承载比CBR公式,它属经验性的,对某一给定条件得出一个设计厚度;(b)多层弹性体系法,它是分析法,对给定荷载和路面几何尺寸条件下的路面体系得出应力应变和弯沉,并与建立的破坏标准作比较,从而确定路面的性能,两种方法都是确定性的,即被设计的一个唯一的路面体系使用,一组求解课题所必需的输入参数变量。输入的变量是唯一的。在CBR法中,路面厚度是按所给的土基CBR值、车轮荷载和几何尺寸、轮胎接触面积和设计的概率水平。材料变异性对路面性能的影响,是在工程师选用土基CBR值来考虑的,设计安全因素包含在施工规范中,如压实要求等。
The AMPC airport flexible pavement design is usually based on two methods, (a) the California CBR formula, which is empirical and gives a design thickness for a given condition; (b) a multilayered elastic system approach, It is an analytical method that derives stress-strain and deflection from the pavement system for a given load and pavement geometry and compares it to established damage criteria to determine the pavement performance. Both methods are deterministic, That is, a unique pavement system designed to use, a set of input parameter variables necessary to solve the problem. The input variable is unique. In the CBR method, the pavement thickness is based on the CBR of the given foundation, the wheel load and geometry, the contact area of the tire, and the probability level of the design. The effect of material variability on pavement performance is taken into account when engineers choose to use CBR values for earthquakes, and design safety factors are included in construction codes such as compaction requirements.