Compared with uniaxial experimental study on creep and relaxation properties of rock

multi-axial experiment study is very few

which makes 3-D creep and relaxation model of rock to be just simply extension without enough experiment verification.For gathering useful data and prompting development of multi-axial creep and relaxation model of rock

the following experiments were done with the red sandstone obtained from somewhere in Guangdong Province

China:（1） creep and relaxation properties of rock under different confining pressure;（2） creep and relaxation properties of rock subjected to pressures from two directions;（3） comparison of creep and relaxation properties between air-dried and saturation samples under multi-axial pressure.By analyzing experimental results

some features or phenomena are found on creep and relaxation properties of the red sandstone

for example

when axial pressures are the same

the higher confining pressure is

the smaller creep is

when confining pressures and relaxation time are the same

the higher σ1 is

the larger relaxation of σ1 is;etc..All these are of some significance to theoretical study of rock mechanics and the design and construction of practical engineering.