Study On Geological Sketch Of Tunnel And Identification Of Rock Crack Based On Photographic Measurement

Geological record is an important link of safety and risk control means and essential in tunnel construction. Geological sketch is the core content of geological logging and rock fracture characteristic analysis is the main analysis function of geological sketch and the general structure of rock mass. In order to implement the chance of geological logging to the computer-aided operations and information management and to improve technical level of geological logging in tunnel construction, this paper aiming at the characteristics of tunnel engineering construction, uses Delphi fast and efficient development language and the component GIS secondary development tools of Super Map Objects 2008 to develop a geological logging module for the tunnel face, combined with positive photographic image measurement theory, digital image processing, engineering geology, geographic information systems and programming multidisciplinary integration to research and a geological sketch and fracture analysis program system for tunnel excavation occurrence and the analysis of the characteristics of rock crack.System developed in this paper is based on a pass through the drawing geometry processing, calibration and after setting, achieving the extraction, editing and operational integration of geological logging information and it can effectively improve the quality of the geological logging of the tunnel construction.The main contents of this paper are listed as bellows:(1)Through the literature inductive analysis, expounds the tunnel based on digital photography, the excavation surface geological logging principle, clear the common tunnel type plane display and three dimensional space coordinate mapping relationship and conversion equation.(2)The calculation principle of the production factors such as the direction and the dip angle of the rock joint surface is studied, and the drawing method and calculation of the stratum of the tunnel based on GIS are realized. That is by way of human-computer interaction in the sketch map painting line, tracing point to obtain rock joint surface occurrence elements of information to realize the semi automation of geological sketch.(3)The visual representation method of rock mass fracture based on GIS vector editing function and digital image analysis is studied and programmed. In view of the tunnel excavation face or rock sketch with cracks, the distribution characteristics of the fracture are analyzed by calculating the fractal dimension of the rock fracture image, in order to further study the characteristics of the joint structure of the rock mass and rock mass.(4)Based on GIS two development platform, the visual programming system of tunnel geological sketch and rock mass crack analysis is developed. The main functions of the system include the workspace create, import sketch map, key points in the image with the tectonic line drawing, space coordinate conversion and query, strata structure line shape calculation, fracture character image analysis, geological sketch calculation results of Excel and word table export.