Abstract:Large diameter bored piles have been used for Lugushan over sea bridge in Qindao.The effects.of sea tide on formation pressure and optimum set depth of steel comductor are analyzed with reference to consruction practice.Proper placement of the mud circulation system for marine drilling,formulation&maintemance of seawater mud and hole wall protection are also discussed.

Abstract:Difficulties encountered in drilling large rolling rock and boulders are basically eliminated by useof a combined drilling techitiqee which combines cable pelcussive drilling,explosion with tungston carbide rotary drilling methods.

Abstract:Analysis is made on forces exerted on the reinforcement cage during casting.Set-up a mathematicalmodel of lift-up of teh non-full length reinforcement cage of bored pile.The mode is examined and field casesare listed.

Abstract:Foundation pit excavation causes large volume of sand to inlux subsurface into the pit,resultingin surroundig foundation ground caveng,An effective way is to stabilze the sand formation using boreholegrouting method,and fill and reinforce the caving foundation using packing and buried tube grouting method.

Abstract:Core drills are suooessfully converted to large diameter construction drills.However the bevel gears areoften worn out in field application. An analpsis is made on factors influendng the service life of bevel gearswith the improvenent measures proposed.

Abstract:By establishment of a functional relation of strode & mouning position of angle-shift cyl-inder on the top head dnre sllde rail and by computer computatiom,the actual cases of the talculationasults of the cyinder stoke & mounting position are obtained. The authors also put forward their opinins onthis sort of problems.

Abstract:The basical principle of the project mehod constructon work is described.With respect to the statusquo of medium and small scale costruction enterprises of M.G.M.R., some advice is made on how to maximumlyincrease the production & operation ability of constructinn enerprises an dpush forward M.G.MR.'s explorationconstruction industry.

Abstract:The project management in Jihao drill ite in Qindao is analyzed theoretically and practially,with emphasis on execution and fulfilment of the managrment used in constrction projects.

Abstract:Carbide core bits of different sizes are used to perform drilling analogue test in the some rocks,bysorting of test data and using of numerical valule analysis method,the correlatioln equqtion between bit diameterand penetration rate under teh iptimized drilling is set up.

Abstract:With referemce to the first case of cutting a window in the dual case set in a directinal well for side traking process and its effect in directional wells. Methods of incteasing side tracking efficiency and reducing cost are presented It is concluded that whether side tracking in derectional wels succed or not mainly depends on the orientatio of the deflection wedge.

Abstract:A mathematical model using the fuzzy hierarchy analysis for rock blastability appraisal is presented;the basical principle and the calculation of this method are described;and is applications are illustrated by fieldcases.

Abstract:Advances in simulated wellbores for deep drilling are reviewed;the structuual program for devel-oping new generation simulated wellbores for deep drilling is presented with a feasibility analysis on some criticaltechniques; and finally,a detailed desceription is made on the important basical theories related to simulated wellboresfor deepwell drilling.