Abstract:According to the characteristics of existing environment and natures of gas hydrates, a new gas hydrates sampler with hole bottom freezing is developed. The sampling was realized by wire-line coring with liquid nitrogen as external cold source. The paper describes the freezing method, operating principle and the main structure features.

Abstract:In Zhangjiawan groundwater detection base of Tongzhou in Beijing, 34 groundwater monitoring wells were completed by the first sonic drill（CRS-V） which was imported from Holland. The paper discusses the sonic drill about the structure and working principle, as well as the construction process and equipment matching; especially introduces its unique advantages and functions expansion.

Abstract:To verify the sampling effects of YGL-S100 sonic drill in complex strata, the drilling experiment was carried out on the deep overburden layer where Xiangjiaba hydropower station is located. The paper expounds the technical characteristics of YGL-S100 sonic drill, various parameters and the construction technology in the drilling process.

Abstract:Vibrations influence normal and stable work of gear pair. In gear pair design process, inherent frequencies of gear pair should avoid working frequencies. Vibration analysis is made on the gear pair of SP-I-01 hydraulic top drive drilling system, the first 6 order inherent frequencies and the corresponding mode shape graphs of the gear pair have been obtained. The maximum operating frequency is calculated and by comparing with the inherent frequencies of the gear pair, the result is that the maximum operating frequency is lower than the inherent frequency of the lowest order, which meets the design requirements.

Abstract:In the survey project in Yewu depression salt mine, it was required to core at the depth of more than 2000m under the ground surface. According to the requirement of the project book, small diameter core drilling and large diameter petroleum drilling and hydrological well drilling technologies were adopted. With the collection of the advantages of several types of equipment and tool by the new technology of combination of petroleum drilling and wire-line coring , the construction was effectively completed with low cost. The paper introduces the match of equipments and tools for large diameter deep drilling in salt mine, which can be the reference to the similar projects.

Abstract:The low temperature resistance of drilling fluid is one of the keys for core drilling in Antarctica ice sheet. According to the characteristics of ice core drilling and the special requirements for drilling fluids in Antarctic, based on the comprehensive analysis on the application experience of ice drilling fluids both in China and abroad, theoretical study was made on organosilicon, fluohydrocarbon, aliphatic monocarboxylic acid ester and aliphatic dibasic acid ester, their viscosity and density were tested under different temperatures and the mechanism of changes in viscosity and density were also analyzed. The result indicates that the hydrogen bond strongly influences the viscosity temperature coefficient of the fatty acid ester, and the lowest viscosity temperature coefficient of drilling fluid could be obtained if there is no hydrogen bond formation. Besides, the increase of the density mainly depends on the shrinking volume of the drilling fluid; the chemical structure and morphology have nothing to do with the change of density. These results have theoretical and practical significance for the selection and optimization of the ultra-low temperature drilling fluid system for ice core drilling in Polar Regions.

Abstract:With the case of deep drilling, the paper introduces the deep drilling construction technology in an iron mine of Wuyang and discusses the accident prevention and treatment measures, which can be reference to deep drilling in the similar project.

Abstract:According to the drill pipe breaking-off accident often occurring in drilling construction, analysis is made on the accident causes by the field cases, the suggestions to prevent or reduce the accident are put forward.

Abstract:According to the drilling difficulties in Liuguan Pb-Zn mining area in Henan, by optimizing borehole structure and putting retrievable casing in the upper complex hole section, the construction schedule was accelerated; with low pressure and slow speed wire-line coring hydro-hammer technology, the obvious effects of drilling deviation control and less borehole curvature were received, the construction quality and success rate were improved. Based on the field analysis，mud formulation was constantly adjusted and inert leaking stoppage material was added to different loss zones. A set of wall protection and leaking stoppage technology suitable for the complex formation of this mining area was developed.

Abstract:Puguang gas field is a large-scale equipped marine gas field which has been successfully developed by SINOPEC. In this article, the drilling practices of ultra-deep wells in Puguang gas field were summarized comprehensively. The practices were divided into the exploratory stage, developing stage and gas drilling stage. From 0.99m/h in the exploratory stage, the ROP was raised to 1.70 and 2.61m/h in the developing stage and gas drilling stage respectively. The drilling speed-increasing effect is very obvious. Some proposals are put forward to speed up the progress of ultra-deep well drilling technology for Sinopec.

Abstract:Along with the sustainable construction and production in Daniudi gas field in Northern Erdos work area, the large scale application has become the major technology in gas field development. But because of the unfavorable factors of lithological changes, rock drillability differences, instability of mud stone and leakage in light fracture and low pressure reservoir; the uncertain factors of lubrication performance of drilling fluid, cuttings carrying capacity and the removal of cutting bed; as well as the collapsing block-falling in drilled mudstone coal seam and some others, there were still many difficulties to improve the drilling efficiency. Based on the systematically analysis on these bottlenecks, the technical schemes were put forward.

Abstract:In drilling construction of borehole CY-1 in a salt mine of Hebei, wall protection by mud was a technical difficulty. According to the different construction conditions, sublevel mud scheme was adopted to ensure construction safety and quality. The practice shows that this wall protection technology is feasible. The paper introduces the wall protection technology with saltwater mud in borehole CY-1.

Abstract:Well Gushen-3 is a risk wildcat well in Gulong faulted zone of the rift area in the western part of Songliao basin, the target layer is Yingcheng group. The gas drilling was used in the non-target zone section of 3180～4460 m, that was Quantou formation～Denglouku formation, the total footage was 1208.72 m. By the effluent prediction and according to the features of gas drilling, optimizations were made to well structure design, BHA design, bits and parameters as well as gas injection rate; drilling by gas-liquid conversion, the mechanical drilling speed reached 6.36 m/h, which was 4.54 times increasing than the adjacent well Gushen 1 (average ROP of 1.40 m/h); and the drilling cycle was shortened 43.56 days. The new records of gas drilling were created that footage and service life reached 674.87 m and 101.88 h with a single bit.

Abstract:With the construction case of network media building in Henan, the paper introduces the design selection process of deep excavation and the construction situation. Analysis is made on the results of deformation monitoring about horizontal deformation at top edge of excavation, horizontal deformation of the crown beam and cable tension. Some suggestions are put forward to the design of pile-anchor structure and construction.

Abstract:Based on the analysis and comparison of advantages and disadvantages of traditional deep foundation pit enclosure systems, a new enclosure system was created by combining high-pressure jet grouting curtain with pre-stressed reinforced concrete square pile, which was applied in the projects, and the construction cost was greatly reduced with huge economic benefits.

Abstract:GFRP Reinforcement is a glass fiber reinforced composite, which was applied in the GFRP reinforcement soil nailing supporting system of a foundation pit engineering, and the supporting system collapsed in a rainy season. By the analysis on the failure causes, some constructive reflections are put forward to the application of GFRP reinforcement in soil nailing supporting system.

Abstract:The paper discusses the importance of groundwater monitoring in deep foundation pit engineering in urban area and introduces the problems of groundwater monitoring: not enough attention to the groundwater monitoring, unreasonable design and construction of monitoring hole and so on. By taking the reference from some standards of water conservancy and geological industries, some suggestions are presented to the quality inspection of water level monitoring hole.

Abstract:In permeable formation, the diffusion and consolidation states of pile-bottom post grout were inspected with the sampling method. The practicality samples showed that in relatively homogeneous strata, grout diffusion were with different downward, sideward and upward penetration ability, each was the strongest, the second place and the weakest. In the alternating strata of coarse and fine particles, more coarse was the particle, the better was the permeability, the farther was the diffusion and the higher was the cement content; and in the same strata, the nearer to the grout outlet, the higher was the cement content. The sampling also indicates that the pressure and temperature at the pile bottom are different from the surface; especially in the environment with plentiful groundwater, the time delay for cement slurry condensation curing was very obvious.

Abstract:Based on the analysis on the problems in traditional joints of underground continuous wall, a set of effective construction method is put forward, that is continuous closed steel box joint. The paper introduces the construction technology of underground continuous wall with continuous closed steel box as joint and the effects.

Abstract:It is hard to complete a deep hole for anchor cable in thick accumulation body, especially for those with depth of more than 80 m. In Zhentouba first stage hydropower station, in order to complete the deep hole in 1# accumulation body, the combination of single layer casing and wall protection grouting was selected. The practice shows that this technology is effective to complete deep hole for anchor cable in accumulation body.