Abstract:Gas hydrate was discovered in northern South China Sea by drilling in 2007; and in September of 2009， it was discovered in frozen earth zone of south margin of Qilian Mountain in Tianjun county Qinghai Province. This discovery will play an important role for adjusting energy resources structure and alleviating the energy resource shortage of China. But the exploitation of the gas hydrate and its security are serious problems that are generally interested by the specialists in the world. In this paper, the Russian professors proposed new thermal exploitation technology of gas hydrate using double vertical wells drilling with long horizontal displacement and with heat produced by radioactive (nuclear) waste materials is introduced. This is a patent technology which can be referenced for the study on the exploitation of gas hydrate in China.

Abstract:For the calculation of laminar flow pressure drop of the Bingham drilling fluid in the drilling tools, we need to solve a nonlinear equation, which is usually done by an approximate formula. To solve this nonlinear equation, a numerical iterative arithmetic is put forward and the convergence of the arithmetic is demonstrated to give the upper limit of maximum iterative steps. By many actual cases and theoretical analysis, it shows that the arithmetic in this paper has a very stable convergence and very fast convergent speed with accurate calculated value of pressure drop.

Abstract:Along with the continuous extension for application of underbalanced operation and the managed pressure drilling, in order to furtherly carry on the control and the management to these two technologies; according to the risk grade, application category and fluid system, UBO/MPD committee subordinating to International Association of Drilling Contractor classified these two technologies into 6 levels, 3 categories and 5 systems. The paper firstly introduced classification system; analysis and appraisal were separately made on the underbalanced operation and the managed pressure drilling methods about the operation goal, fluid type choice, advantages and disadvantages as well as the applicable scope, so as to provide basis for selecting proper drilling method in construction operation.

Abstract:In design of directional drilling trajectories, only magnetic deviations were taken into account, while effects of meridian convergences on directional drilling accuracy were not included. When the well spacing exceeds 400m, the meridian convergence will result in a maximum error of 10m, indicating a substantial impact on directional drilling accuracy. This paper presents a simplified method of meridian convergence calculation with the geographical coordinates of the well collar with an error less than 20%, which can meet the field requirements. It has been proven by use of the RMRS system that the drilling error to the target is reduced to the minimum in 29 pairs of intersected wells. It shows that consideration of meridian convergences provides important guidance to the precise design and drilling of longreach horizontal wells, intersected wells and pipeline installation wells.

Abstract:Under safety condition, improving drilling rate is the goal and urgent task for the drilling engineers and technicians．According to Daqing Changyuan general drilling rate equation, the analysis was made on main factors affecting drilling rate and effective approach to improving drilling rate, which was helpful for drilling engineering design. Actual drilling data of well Yingshen 1 and Dashen 2 were verified by general drilling rate equation with the fault only 4.3% and 4.8% between the predict and actual drilling rate, good coincidence rate was acquired.

Abstract:Because of the complex formation in Zhaishang gold mine, drilling was difficult with collapsing and diameter shrinkage. Several kinds of drilling fluids were tried to solve these problems with less effect. Experimental application was made on plant gum low-solid mud with ideal result. The paper analyzed the difficult cause of wall protection in the mine and introduced the application techonoly of drilling fluid.

Abstract:A series of difficulties were encountered for drilling in Xianghedaquan vanadium deposit: quaternary loess & diluvium gravel, thick weathered layer of fine sand rock; broken upper part with borehole collapsing and block falling; powder clay rock for lower ore bed, hard for coring and boring. These difficulties were effectively overcome by pertinent drilling technology and technical measures.

Abstract:In the southwestern margin of Ordos basin, 6 Cretaceous conglomerate groups were distributed with abundant geology and hydrogeology information. The paper introduced the B5 well in this area about the well structure design and the construction technology, which could be used for prospecting and longterm observation, coring and pumping test. This well construction proved the possibility of multipurpose by a single well and played demonstration functions for hydrogeology survey in Ordos basin.

Abstract:As the new products with high efficiency, convenience and energy-saving, YZX series high efficient hydro-hammer and SYZX series wire-line coring hydro-hammer overcame the unfavorable factors of traditional hydrohammer. By the basic theoretical research, structural optimization design and scale development, hydro-hammer technology has been largely improved in China and good application result is achieved in construction practice.

Abstract:Because of the performance requirements of drill operation on rotating, feeding, hoisting and falling hydraulic circuit for hydraulic drill, the traditional ordinary hydraulic system consisting of manual control valve and pump is considered to be backward, which has poor adaptability in drilling control in different formations. But the load sensing hydraulic circuit has good adaptability for drilling work, which can promote the efficiency of drilling, the hydraulic system is with energy saving, low temperature and efficient transmission. The article introduced the working principle of load sensing hydraulic circuit on hydraulic driving heading core drill, system characteristics and adaptive capacity to drilling work load.

Abstract:The paper introduced the distribution, engineering geological conditions and characteristics of collapsible loess in West Henan area, summed up the construction foundation selection in such geological conditions and analyzed the related issues.

Abstract:By the field case of excavation pit engineering, the paper introduced an excavation pit supporting design and the construction requirement under the condition of bedrock exposing on one side and deep soft soil layer on the other side with high angle bedrock surface and great disparity of active earth pressure, which could be the reference for the similar engineering.

Abstract:Based on the practice of precipitation project in Xiongmaohuandao station of Beijing subway Line10#, tubular well construction technology with reverse circulation drill and foundation pit dewatering by the combination of suction and seepage were introduced; construction technology of groundwater monitoring and settlement monitoring, environmental impact of dewatering and the countermeasures, problems in construction and the treatment experience were together summed up.

Abstract:The special engineering borehole with large diameter was applied more and more extensively in coal mine safety production in recent years, and casing collapsing frequently occurred in the construction. The paper analyzed and studied the accident causes and put forward the corresponding technical measures according to common problems of the casing failure cases.

Abstract:According to the difficulties in construction of vertical borehole with large diameter in bedrock, the paper introduced the successful construction process of large diameter vertical borehole in bedrock and full-hole large diameter steel pipe laying by small diameter pilot hole, movable guide apparatus, large diameter borehole monitoring with small diameter pilot hole and large diameter expanding bit with advanced pilot.

Abstract:According to the theory analysis and numerical calculation result, the reinforcement scheme of rotary jet grouting pile in the approach sector is designed. According to the construction organization and quality inspection, it was indicated that restrained reinforcement by high-pressure rotary jet grouting pile could bring good reinforcement result and economic benefit.

Abstract:The paper introduced the application of the recharge water source heat pump technology both at home and abroad and expatiated the experiment, engineering application and attention points about recharge water source heat pump system in Shunyi District, Beijing city. Test and engineering application showed that it was feasible to build the pressure recharge system by use of submersible pump lift. Theoretically, it is inevitable that the recharge yield reduced in the process of recharge, while not completely caused by the solid particles and chemical blockage.

Abstract:In HDD, the tension and torque acting on the bit are important foundations for the design of drilling and construction. The tension-torque mathematical model is established by the mechanical analysis on extrusion type reaming bit and the factors which affect the results of the model are analyzed entirely. The model was tested according to the construction data, the results agreed with field data well. Therefore, the model plays an important role for construction design optimization on HDD with extrusion type reaming bit.

Abstract:It was only about two decades that horizontal directional drilling crossing was introduced into China as a type of trenchless technology, which was rapidly developed in this period. As urbanization was accelerated in China, and along with the intensity of large-scale infrastructure construction projects increased, more and more large-scale projects of pipeline crossing were carried, but risk assessments on these projects are still few. The paper introduced a largescale gas pipeline project with large amount investment and serious risk; the risk assessment prior to project construction is necessary. Firstly index system was established based on the project evaluation by the experts, then the synthesis of advantages of fuzzy comprehensive evaluation method and AHP (analytical hierarchy process) was adopted and according to the evaluation data, the judgment matrices and membership matrices of this index system were built; and the weight vectors and membership vectors were calculated by Matlab programming, risk value of the project was obtained and the corresponding conclusions was drawn.

Abstract:According to the engineering case of an expressway in Guangxi, the paper introduced the application of rock and soil grouting technology in landslide treatment. By the scientific demonstration, landslide treatment scheme was planed; and by the grouting experiment study, the design parameters for grouting were obtained. The rock and soil grouting technology was successfully applied in landslide treatment with satisfied effect.

Abstract:In order to get the moment of retaining pile during the excavation and the regulation of lateral displacement changing with excavation depth, comparative analysis was made on the internal force and displacement of retaining pile both with and without steel support during the excavation in different crossing-sections. Two-dimensional analysis was made on the excavation soil in Zhongjie Station with PBA method by MIDAS-GTS to determined the location and the spacing of the steel support and the conclusion was got that the largest moment of piles and the displacement would be reduced 278% and 317% respectively with steel support.

Abstract:The ventilation layout and ventilation equipment of the longest expressway tunnel (Maijishan tunnel)construction with blind heading interiorly were introduced, the relevant parameters were calculated according to the standard methods, the verification of numerical simulation for the construction ventilation scheme was processed based on the finite element fluid dynamics software FLUENT. Some problems encountered during the ventilation process and the solutions were described to obtain a good tunnel ventilation effect and create a comfortable and efficient work environment.

Abstract:The methods of hazard source recognition, risk assessment and risk control written in Occupational Safety and Health Management System Standard（GB/T 28001） were briefly outlined in the paper, which can reduce safety risk and improving safety operation performance.