Based on the factors of reinforced slope computed with Holland method and Sweden method

the tests of single index and multiple factors were designed according to orthogonality table in the paper. Associated with the example of slope with the height of 20 meters reinforced by geogrids

the sensibilities of the factors influencing on the stability of slope were analysed. In sequence

the sensibilities of factors are as follows in their magnitude order: cohesion

angle of internal friction

seism

unit weight

the reciprocation of number of geogrids layers and space between layers

number and tensile strength of geogrids

slope angle space between geogrids layers

overload in top of slope and underground water level. The discussion laid emphasis on the effects of reinforcement. If possible

backfill with high cohesion and big angle of internal friction should be adopt preferentially. When reinforcements are needed

under the condition of the same total tensile strength of reinforcement

it’s better to install more geogrids with moderate strength than less ones with high strength.