The paper also detailedly discusses california bearing ratio ( cbr ) method of evaluating the flexible pavement flotation characteristics and portland cement association ( pca ) method of evaluating the rigid pavement flotation characteristics 并比较深入地探讨了对飞机软道面漂浮性评估的加里弗尼亚支承比方法和对飞机硬道面漂浮性评估的波特兰水泥协会方法的算法原理及理论根据。