Abstract:In drilling engineering practice, sometimes it is necessary to increase drilling pressure for solving the problems of drilling in complicated conditions and treating accidents. One selected drilling machine only gives a constant feed pressure, but the specialists of Ukrainian National Ming University have developed a new hydrodynamic amplifier of drilling pressure based on the principles of hydrodynamics, which can solve the drilling difficulties in complicated conditions. The paper introduced the working principle of hydrodynamic amplifier（ГУОН）and the technical performance index, the comparison was made between the testing results and theoretical calculation.

Abstract:CBM multiple-lateral horizontal well is a coalbed modification technique combined with well drilling, completion and stimulation, which has great development in China in the past years. According to the development situation of CBM multiple-lateral horizontal well in China, the paper discusses the technical difficulties and key technologies and presents some conclusions.

Abstract:This paper introduces the examples of sidetrack drilling at artificial cement hole bottom with continuous whipstock bypassing down-hole accident drilling tools and the technical points of sidetrack drilling technology.

Abstract:Gas hydrate is a potential clean resource. There are strong conditions in Mohe permafrost region for gas hydrate formation. According to the local geological conditions and the technical requirements of hydrate exploration and development, the appropriate borehole structures and drilling parameters were determined, and drilling equipments were rationally selected. Low-temperature drilling mud, drilling mud cooling technology and large diameter wire-line coring drilling were applied in drilling process for rapid coring to reduce the decomposition of gas hydrate. The paper described the key technologies of drilling construction for gas hydrate in Mohe permafrost region.

Abstract:Gas outburst is the important reason of borehole accidents in soft coal seam drilling. In this paper, the formation mechanism of gas outburst and the causes of borehole accidents were analyzed and the methods of common problems in air drilling technology were summarized. All of these have important reference in soft coal seam drilling.

Abstract:The formation is typical complicated in Chenghe mining area of Weibei, drilling construction is difficult with low drilling efficiency. By the analysis on the difficulties in drilling process, the drilling technical experience was summed up; according to the drilling in thick loess layer, borehole leakage and collapsing, hard rock and pulverized coal taking, the relevant technical measures and drilling technologies were put forward.

Abstract:The paper introduced a new SPT-600 trailer-rig about the general structure, system working principle, main technical parameters, structural performance of main parts and the related drilling tool matching to the rig, analyzed the performance characteristics and the advantages. Some attentions in the rig development were summed up.

Abstract:Many new methods of shallow groundwater intake project develop fast in recent years， including seepage well, large-diameter well with radiation wells, confluence wells nearby river, household well and small concentrated water supply. The operating principles, the application conditions and advantages of these water intake methods are discussed in this paper with some successful engineering cases.

Abstract:The special petroleum drillable float collar and float shoe are applied in the casing running in large diameter borehole of coalmine and well cementing. With this new technology, the conventional cement base setting or floating plug by welding steel plate to the case+one-way grouting valve is replaced and the procedure of casing running and well cementing are simplified. By these means, the engineering cost is saved and the well quality is guaranteed. The paper introduces the technology application and the effect in recharging hole of Wutongzhuang mine.

Abstract:Combined with the engineering case of the retaining structure design of a super high-rise building in Suzhou, the reinforcement steel was optimized; comparison was made on the strength, stiffness and economic of surrounding non-uniform reinforcement and uniform reinforcement; and study was made on the stress deformation characteristics of foundation pit under the condition of retaining piles with different length. The results show that there is little change in mechanical behavior when non-uniform reinforcement steel and retaining pile with different length are adopted, but low project cost, short construction period and the best economic and social benefits can be achieved.

Abstract:In the mid 1960s, the proven reserve was 93 million tons in Zhongguan iron mine area. Because of the deep groundwater table and difficult drainage, curtain grouting was adopted for water control to avoid high mining cost and protect the ecological environment. The curtain grouting has high demand of borehole verticality, hole deviation of the whole section should not be more than 2 m. Gyroscope directional deviation correction was explored in practice with success.

Abstract:By the superior performance, the stable single dense slurry was applied in the consolidation grouting for the weak resisting rock of left bank of Jinping-Ⅰhydropower station with obvious effects in control grouting. Comparing and selection of water-cement ratio made by indoor tests has been applied and popularized in the productive test, which also has ideal effects in increasing holistic resistance to rock deformation.

Abstract:The bored-grouting pile with diameter of 1000～2000 mm and depth of 100～130 m are often used in various projects. Pump-suction reverse circulation was traditionally used in the hole not more than 80 m deep, but by the improvement on the existing reverse circulation drill, the efficiency of pump-suction reverse circulation was greatly improved with pile hole of 18 m in diameter and 131 m in depth finished.

Abstract:This paper gives a detailed description about the application of CFG pile composite foundation treatment technology in railway subgrade engineering of Beijing-Shanghai express railway, summarizes some issues which encountered in the construction process and presented new views, opinions and suggestions.

Abstract:By the laboratory tests, the soil conditions of a container yard in Shandong were compared as well as the variations of ground deformation and strength characteristics before and after the consolidation. According to the comparative analysis on the field test data of 3 sites, analysis was made on the distribution of pore water pressure caused by dynamic compaction loading in different formations; and the applicable conditions for consolidation of saturated soft soil with dynamic compaction was discussed.

Abstract:Take an engineering example of a coal preparation plant, discussion was made on the application of dynamic compaction method in collapsible losses. The applicable conditions, the scheme determination principles, the influence of foundation soil water content to dynamic compaction construction effect and especially the determination method of dynamic compaction foundation bearing capacity by composite foundation theory were put forward.

Abstract:Analysis was made on the diamond positioning arrangement mode and parameters of impregnated diamond bit, 40/45 mesh and 50/60 mesh diamond positioning arrangement drill bits were designed and produced. In the drilling experiments of Mengcun mining area in Guangxi, the service life of 40/45 mesh diamond bit is respectively 1.84 times of conventional bit; the service life of 50/60 mesh diamond bit is respectively 2.74 times of conventional bit, and the drilling rate increased by 19.7%.

Abstract:This article analyzed the major risks and serious consequences in the large slurry shield construction of Nanjing Yangzte River tunnel under the complicated geotechnical and hydrological conditions. The engineering risks were evaluated and summed up by experts and professional engineers with prevention measures. The emergency countermeasures were formulated to reduce and prevent the major safety and quality accidents.

Abstract:According to the Qinshan nuclear power plant 2nd phase extension engineering, the monitoring and control on blasting vibration were made in the large foundation pit excavation of new expansion nuclear power plant near the operated one. The effective control on blasting vibration was realized by theoretical analysis and monitoring, and the security of the operating nuclear power plant was ensured. The vibration absorption measures summarized in this paper could be reference to blasting vibration control of other nuclear power plant.

Abstract:With the development of economic society, the mineral resources requirement is becoming stronger and there are rare development opportunities in geological exploration. In the geological exploration operation process, the management of engineering explosive materials is the difficult and vulnerable point. The paper discussed the safety management of engineering explosive materials in 5 steps.

Abstract:In drilling engineering practice, sometimes it is necessary to increase drilling pressure for solving the problems of drilling in complicated conditions and treating accidents. One selected drilling machine only gives a constant feed pressure, but the specialists of Ukrainian National Ming University have developed a new hydrodynamic amplifier of drilling pressure based on the principles of hydrodynamics, which can solve the drilling difficulties in complicated conditions. The paper introduced the working principle of hydrodynamic amplifier（ГУОН）and the technical performance index, the comparison was made between the testing results and theoretical calculation.