نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه مهندسی معدن، دانشگاه صنعتی همدان
2 دانشگاه تهران
3 دانشگاه تربیت مدرس
4 دانشکده فنی و مهندسی، دانشگاه تربیت مدرس
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Rock joints and micro cracks have an important effect on the failure mechanism of rock masses. Rock mass failure affect the stability of rock engineering project. Therfore investigation of failure stress of rock mass help engineering to desing the rock engineering structure with high safty. Failure stress that is one of the mechanical propertis of rock masses controls the loading capasity of rock structures. Several parameters have a dominant role on the failure stress of rock masses such as mechanical properties of rock mass, normal stress, ratio of joint surface area to total shear surface area (JC). In this paper, the crack coalescence stress was predicted using both of the GWO and GEP algorithms. Eight import parameters have been used such as normal stress, JC, compressive strength, tensile strength, Poisson ratio, Young modulus, cohesion and friction angel. Totally 450 data obtained from jointed rock like samples tested under direct shear. Three different coefficients of “R2”, “RMSE” and “MAE” were used to evaluate the applicability of algorithms. The coefficients of GWO and GEP on trained data were 0.962 and 0.938 while their values on tested data were 0.996 and 0.981. the GWO has the best applicability on the coalescence stress prediction. The results show that the coefficients of RMSE and MAE in both of the train and test stages in GWO algorithm was less than GEP algorithm. This shows that GWO algorithm has the best application in comparison to GEP. The normal stress and JC has the maximum and minimum effect on the crack coalescence stress, respectively.
کلیدواژهها [English]
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