The Research Of The Construction Of Tunnel With Block Theory

The construction of tunnel makes the balance of stress about original rock destroyed. The stress of rock around tunnel distributes again,and appear a phenomenon of stress concentration.If the intensity of stress is more than the rock's around tunnel, the wall rock around tunnel will be damaged,some blocks will be along the sliding surface, resulting in losting stability.It brings great jeopardy, such as inundates equipments, plugs the trenches,and what's more,leads to some construction personnel injuries and deaths,or effects schedule,and makes engineering construction suffered a great loss.Block theory for rock mass researchs the stability of block which taked form different shape,length,span cutting structural surface. With the understanding of domestic and foreign scholars and in-depth study.Block Theory has become an effective way to analyse the stability of engineering rock mass, so it is applied all around the world.This article is on basis of construction site geological statistical date, including exposed thes tructural of the surface with digital photogrammetry to make reconnaissance records when it is excavated and bases former geological material to forecasting when it is unexcavated ,and set up a database to judge key block.According to obtainable date to analyse and judge the broken types,slide modes,stability of key block with the ultimate balance analysis,analysis of wedge-shaped body,the analyse of the maximum possible movable block and then adopt appropriate support measures .Make use of that theory and adopt Access to set up datebase and Visual Basic language to programming design to generate the analyse program.Procedure includes stability analysis and design of bolting.User can apply the program's data directly or add data to database in his mind,it's very convenient.The program brings simple way for common geometry,mathematics and physics,such as calculate for complicate area and volume. Program can output the bolck's site,size,plane figure and sectional drawing which is formed by jointed block in course,and according to block to analyse gliding stress,apply suit anchor bolt and anchor deepth ,and it can output bolting sketch sections and profiles ,it is more straightforward.Put research results into engineering practice to inspect its advance and validity.Make good use of block theory to tunnel construction, the method is simple and easy to manipulate.