Abstract:Underpinning of high storeyed building foundation using sheetpiles constructed with poly groutingis realized by combination of jet grouting and pressure grouting. Some jet parameters in jet grouting and newviews are presented on the base of investigation and field tests. Expected effects are obtained by application ofthese test data and views resulted from study and analysis in foundation reinforcement for No. l high storeyedresident building of Beijing No, 1 Housing Service Company.

Abstract:Study is dealt with the jet grouting lifing speed by setting up lab jet grouting modelling device.The modelling results and initial analysis show that piling completion quality will not influenced with groutingspeed properly increased.Tests at a Guang Zhou site indicate that use of medium speed grouting can save cementwhile the pile bearing capacity will not change after the grouting returns to the surface.

Abstract:Complete with triple air/water swivel,kelly bar,triple drillpipe,heavy centralizer,etc,,the singleheaded large diameter DTH hammer can be used to perform advanced drilling technique which combines DTHrock drilling,cuttings removal with reverse circulation by pump suction,hole wall protection with mud and pres-surized air circulation in a closed loop.It is an effective tool to tackle large diameter hard rock and boulderdrilling problems,Development and design of the tool are described.

Abstract:介绍ＭＤ－５０型钻机的结构、参数和特点。该钻机完成了十三陵锚固工程，通过了部级鉴定。

Abstract:经过系统分析总结钻探专家们根据岩石力学性质设计及合理使用金刚石钻头方面的知识和经验，选择了合适的工具，编制成相应的专家系统，便于推广应用。

Abstract:Analysis is made on the heating process for production of kurf diamond bits with medium frequen-cy induction heating, based on which is presented the heating mechanism for kurf diamond bits,with the criteriaprovided for determination of the relative position between the mould and the induction coil,mould design and selection of equipment.

Abstract:利用模拟岩屑分别在淡水、ＣＭＣ钻井液以及用于德国大陆超深井的ＫＴＢ钻井液中进行了沉降实验并测定了岩屑的沉降速度。观测到两种不同的沉降方式─—稳定沉降、摇摆沉降。岩屑的沉降方式与岩屑的雷诺数有关。当岩屑的雷诺数小于１００时，岩屑稳定下沉；反之，雷诺数大于１００时，岩屑摇摆下沉。通过实验测定的数据建立了新的岩屑沉降阻力系数及沉降速度的计算模型。

Abstract:Properties are analyzed for bentonite,sepiolite and leitolite at high ternperature according to thestructural features of clay with clay suitable to high temperature mud proposed

Abstract:With blasting demolition of the cooling tower of Fuxin power Plant,studied is the selection ofblasting parameters for reinforced concrete thin wall structure.The preventive precautions are described.

Abstract:Use of the effect measure analysis can conduct relative rating of rock blastability while at thesame time complete the systematical analysis of it,which is an information analysis method featured with simpleand fast calculation,flexible application and high adapability.