Abstract:

Bearing capacity of rock foundation is an important index in civil engineering. It is based on the uniaxial compression strength R of saturated rock for most civil engineering, and also based on the eigenvalue P of plate loading test for important engineering. Thus, the two methods must have some relativity. It is indicated in the practices that the R method is simple and easy for handling; but R represents characteristics of rock materials which is quite different from the condition of the engineering rock mass. Plate loading test is carried out under the semi-infinite condition; it is more close to the engineering practice. Therefore, the P method is more reasonable than the R method. This article establishes the relativity of P-R as well as the strength characteristics under surround compression on the basis of summarizing 43 plate loading tests results and three groups of uniaxial compression strength tests results on the same position, and collecting 248 groups of triaxial compression test results in Chongqing area. By demonstrating the relativity of P-R，the article brings forward an important conclusion of taking rock saturated uniaxial compressive strength of the standard value of 1.5 times the characteristic values as a foundation bearing capacity of the important conclusions， so as to provide an important reference for optimization of bearing capacity of rock foundation.

Key words: bearing capacity of rock foundation, relativity of P-R, plate loading test, uniaxial compression strength of saturated rock, optimization