The Effects of Salt on Rheological Properties of Asphalt after Long-Term Aging

Table 2

Form of orthogonal experiment.

Test group numbers influence factors	Types of asphalt	Saline concentrations	Soaking durations
1	1	1	1
2	1	2	2
3	1	3	3
4	1	4	4
5	1	1	4
6	1	2	1
7	1	3	2
8	1	4	3
9	2	1	3
10	2	2	4
11	2	3	1
12	2	4	2
13	2	1	2
14	2	2	3
15	2	3	4
16	2	4	1

Types of asphalt ((1) conventional bitumen (no. 70 in China), (2) SBS modified asphalt); saline concentrations ((1) 0.3%, (2) 1%, (3) 3%, and (4) 5%); soaking durations ((1) 1 d, (2) 7 d, (3) 15 d, and (4) 30 d).