3D LASER SCANNING TECHNIQUE AND STUDY ON TRACE LENGTH DISTRIBUTION OF GREEN SCHIST FOR THE RIGHT ABUTMENT OF JINPING I HYDROPOWER STATION ENGINEERING

A number of green schist rocks developed on the right abutment of Jinping I Hydropower Station.They are one of the important engineering geology problems for the stability of abutment.In order to study their trace length distribution,the technique of 3D laser scanning was applied.The zone of green schist outcrop was scanned with it.The elevation of scanned zone ranged form 1720 to 1670m,and fall is up to 50m,scanned area 3500m2.After the interpretation of points cloud for these green schist rocks,resulting trace length data were attained accurately,which provided the possibility to study the trace length distribution of green schist rocks.Based on study,it was found that trace length data mainly were grouped to the zone of 0 to 3m.With the growth of trace length,the number of trace length was getting less and less in every subinterval; in the range from 0 to 9m,samples showed Normal Distribution in every subinterval.As for all of samples,the trace length showed Logarithmic Normal Distribution.