A novel approach to structural anisotropy classification for jointed rock masses using theoretical rock quality designation formulation adjusted to joint spacing

Rock quality designation(RQD)has been considered as a one-dimensional jointing degree property since it should be determined by measuring the core lengths obtained from drilling.Anisotropy index of jointing degree(AI_(jd))was formulated by Zheng et al.(2018)by considering maximum and minimum values of RQD for a jointed rock medium in three-dimensional space.In accordance with spacing terminology by ISRM(1981),defining the jointing degree for the rock masses composed of extremely closely spaced joints as well as for the rock masses including widely to extremely widely spaced joints is practically impossible because of the use of 10 cm as a threshold value in the conventional form of RQD.To overcome this limitation,theoretical RQD(TRQD_(t))introduced by Priest and Hudson(1976)can be taken into consideration only when the statistical distribution of discontinuity spacing has a negative exponential distribution.Anisotropy index of the jointing degree was improved using TRQD_(t) which was adjusted to wider joint spacing by considering Priest(1993)’s recommendation on the use of variable threshold value(t)in TRQD_(t) formulation.After applications of the improved anisotropy index of a jointing degree(AI'_(jd))to hypothetical jointed rock mass cases,the effect of persistency of joints on structural anisotropy of rock mass was introduced to the improved AI'_(jd) formulation by considering the ratings of persistency of joints as proposed by Bieniawski(1989)’s rock mass rating(RMR)classification.Two real cases were assessed in the stratified marl and the columnar basalt using the weighted anisotropy index of jointing degree(W_AI'_(jd)).A structural anisotropy classification was developed using the RQD classification proposed by Deere(1963).The proposed methodology is capable of defining the structural anisotropy of a rock mass including joint pattern from extremely closely to extremely widely spaced joints.

Practice on CSU-CCECC-ABU Cooperation Mode

Student exchange program has been an integral part of higher education,which is popularly known as international joint-,double-,and combineddegree programs,which perform an important role in which its strategic plan is aimed to allow students to become true global citizens.Educational Internationalization strategy brings important benefits to individuals,institutions,and the nation’s education systems.The international student exchange program is not only a powerful tool in strengthening the relationship between two institutions but also helps in building the social,political,and economic development of the partner nations.Also,it is among the most cost-effective ways to project influence around the world.Educational collaboration on student exchange has had a beneficial impact on the status of any country,institution,and students,influencing society at its prominent backdrop for only favourable outcomes and a brighter future.CSU-CCECC-ABU collaboration was the first of its kind,and it was in accordance with both institutions'missions to encourage collaborative innovation to address the needs and problems of Nigeria,the People's Republic of China,and the rest of the globe.This paper first outlined the background concepts and explicitly analyzed the pattern of cooperation practice,research on the National,University,and Students benefits respectively.Second,it provided a comprehensive description of challenges faced by exchange students during their stay in China.Third,suggestions were also provided on how to improve and sustain the educational cooperation practice of the joint degree program.Furthermore,it provides the current status of the CSU-CCECC-ABU cooperation practice.Finally,the paper provides directions to subsequent research studies.