Abstract:Analysis was made on the borehole diameter in diamond core drilling for geological exploration. At different angles, such as coring quality meeting the requirement of studying and evaluating geological mineral resources, economic effect of drilling technology and feasibility of drilling method, the author suggested that B size should be applied to main section for medium-shallow hole construction.

Abstract:The paper reviews advances in protection technology of fractured carbonate reservoir in recent years and chiefly introduces the present situation of damage evaluation, damage mechanism and protection technology about fractured carbonate reservoir. Moreover, by comparing with the protection technology of fragmental rock reservoir, the development direction of the research in protection technology of fractured carbonate reservoir is analyzed.

Abstract:Through laboratory tests, high quality formula of C12 foam mud was optimized, which made the drilling construction successful in serious fracture leakage formation. Time effect increased 0.24m with foam mud than with common mud, average footage of working group increased 0.77m; mud cost decreased 4.71 Yuan/m3, average mud cost of working group decreased 20.95 Yuan. There was no leakage while drilling with foam mud with borehole collapsing solved. The paper also put forward the points for attention of C12 foam mud application.

Abstract:The paper introduced the treatment of borehole and roadway holing in the construction process of large diameter coalmine gas discharging well; and also introduced reaming drilling for hole completion, floating settlement for well casting and wallback cementbackfilling for water shutoff and wall cementation.

Abstract:Water-saving drilling system is a newest technique, which was developed to deal with the serious water scarcity for drilling in arid area and leaking formation. The water consumption in the drilling process was only 5%～20% of the original amount by drilling fluid local circulation at downhole. In the application of water-saving drilling system, in-hole drilling condition can only be judged by observing pressure change in pressure gauge on the surface with low precision. By study, the quantization of working condition in the hole could be observed through the surface pressure variation value and the preliminary theoretical mode was established to have more accurate judgment on in-hole drilling condition.

Abstract:Sulphurized-nitrided compound layer is prepared on the surface of drilling pipe joint material 35CrMo steel by the application of ion nitriding and ion sulfurizing technology. Comparative study was made on anti-wear property under dry friction between original nitriding surface and sulphurized-nitrided compound surface. With dry friction, high-hardness nitriding coat would further intensify the wear, because contact surface of friction pair is lack of lubrication; and sulphurized-nitrided compound coat has better anti-wear property, just because there is a layer of solid lubrication coat of ferrous sulfide on the surface.

Abstract:The paper introduced the ZY-73 coal seam gas pressure measuring instrument about its design idea， working principle， main technical features and service conditions.

Abstract:The paper introduced the experimental study on curtain grouting for dam foundation of Huangjinping hydropower station in thick overburden layer. The hole completion with eccentric casing， grouting test process and grouting effect inspection were adopted and presented as important reference for similar projects.

Abstract:Downhole trouble often occurs while drilling in karst formation, which is very difficult to deal with and lead to great economic loss. Grouting reinforcement was operated in limestone formation of cave fracture and experimental study was made on bored cast-in-place pile technology. The result shows grouting reinforcement can solve the low efficiency of hole forming, downhole trouble and slurry concrete seepage in limestone formation, and it can be the reference to bored pile construction in karst formation.

Abstract:The paper introduced the design and construction of an excavation support scheme for an underground garage, soil-nailing and anchoring shotcrete with wire mesh were adopted with economic and reasonable effect. Some special treatment in this construction could be the reference for the similar project.

Abstract:Analysis was made on the complex surrounding environment, supporting construction design and supporting construction technology of a reconstruction project. According to the narrow construction site and the complex environment conditions, different supporting technologies were applied to various supporting surfaces with construction safety and lower supporting cost.

Abstract:In the old powerhouse extension, grouting reinforcement is processed for foundation. According to the site situation and in view of the karst cave geological features, reasonable grouting parameters and the hole position arrangement were selected to reinforce the foundation with appropriate drilling methods and grouting technology; the measures for special situation was also proposed. By the test after grouting, it was proved that the grouting reinforcement was successful.

Abstract:Hole shrinkage often occurs while bored-grouting pile is constructed in expansive clay， the cause is analyzed with engineering practice， “interval construction” is discussed with the effect presenting， which solved the hole shrinkage problem.

Abstract:The paper analyzed common quality defects of concrete grouting pile with auger drill in serious permeable formation, summed up the important effect of wall protection on concrete grouting pile. Quality acceptance standard of wall protection with mud is quite different to rotary drilling and water drilling for concrete grouting pile, the paper proposed that quality acceptance should replenish an item of wall protection with mud, take care of the diameter after hole cleaning.

Abstract:Physical and mechanical properties and permeability coefficient of the tailing dam were found out by geo-technical engineering investigation and analysis calculation on dam stability was carried out. High would cause instability. Concrete without sand was taken as the caisson wall and the proper construction method was adopted to reach the designing depth. Pumping test and dewatering discharging operation proved that taking concrete without sand as caisson wall could have good permeability and filtration function, effectively lower the saturation line and increase stability of the dam.

Abstract:The left resistance block of Jinping I hydropower station on Yalong River was built on f2、f5、f8、f42-9 faults and the weak belt with lamprophyre vein and deep fractures, reinforcement treatment was necessary. Chemical compound grouting was developed based on cement grouting, the test was introduced in selection of chemical grouting material, determination of grouting parameters and grouting construction technology. Based on the test result, analysis was made on grouting feasibility in lamprophyre vein and testing evaluation was made on grouting effect by the comparative analysis on core, permeability of surrounding rocks, rock acoustic wave and deformation modulus in borehole, it showed that chemical compound grouting has obvious effect on reinforcement treatment in lamprophyre vein. The paper also gives the construction suggestion according to the grouting test.

Abstract:CJ-130 two-way pneumatic DTH is a new type drilling machine, which has been successfully applied to the construction in the field of anchor engineering. However, its design functions were affected in a certain degree by lacking of the operation rules and regulations. On the basis of introduction of the construction equipments and processes of CJ-130, the drilling rules and parameters were analyzed and the key operational points and notes were summarized in order to provide a technical guidance in the future geotechnical anchor engineering construction and provide some valuable references for later researchers.

Abstract:Drilling in gravel stratum is one of present difficulties in drilling area with low drilling speed, short service life of bit and high drilling cost. Experimental study was made on diamond bit with new structures in order to improve gravel stratum drilling and developed a diamond-polycrystalline compound bit. Field tests indicate that this type of diamond bit has a promising application prospect based upon the fact that the drilling rate of diamond bit can be no less than 1.8m/h and the service life of bit reach to 50m with the lower drilling cost in addition.

Abstract:Curtain grouting method is a mature technology applied to block up the underground water in tunneling. But it was applied to block up the high pressure gas what is very seldom. Driving the coal mine tunnel in fracture zone where having vast high pressure gas (CH4 and H2S) was research. On the basis of studying existing research achievements, the calculating method of Hydraulics safety thickness was applied to count the critical safety thickness. The technique combined the pipe roof technic and curtain grouting method and assured the tunneling safety. This research achievement was triumphantly applied tunneling at +450 wind road, Sichuan province Longtan coal mine.

Abstract:Blasting requirements of Yesanhe dock tunnel were analyzed, through the corresponding experience formula calculation， the tunnel blasting parameters were determined to keep vibration velocity in the permit safety of the nearby buildings and promise excavation efficiency.