Abstract:Today, with the increasing of exploration drilling amount, the number of constructed deep hole and extradeep hole also increases greatly, this gave unprecedented challenges in drilling technique and equipment. This article briefly discusses the new progress of drilling techniques, existing problems and countermeasures in the deep hole drilling.

Abstract:Drilling is difficult for coring in large diameter deep hole because of large diameter, complex formation and borehole structure with immature drilling technology. According to the construction of the section of 0～897.66m of hole WFSD-2, the paper introduced the main problems and technical measures in construction. Comparative analysis was made on different construction technologies and technical methods, and some suggestions were put forward to the similar project.

Abstract:According to the requirement of high coring rate in environmental sampling， SDR-100 full hydraulic sonic frequency resonance drill combined with press-fitting sampling drilling tool was used for sampling in Liuchangying. The drilling technology and the problems may encountered in sampling process are mainly introduced in the paper with solutions. The future development of environmental sampling drilling technology is prospected.

Abstract:Based on the analysis on technical difficulties in wire-line coring drilling in Xinjiang Wulagen mining area, the paper introduced the technical methods in bit adjusting, drilling tool grading, mud application and operation technique, and the drilling effects were compared.

Abstract:The geological conditions and coal seam characteristics have many differences in China. The complex formation has many characteristics, such as tectonic coal, high content of gas, high geostatic stress and the broken soft coal seam where plastic flow easily occur. Casing drilling technology is adopted to replace the traditional drill pipe for borehole gas extraction, the work efficiency and gas extraction rate were improved. It also can prevent many accidents, such as sticking and hole collapsing, and remove the bottom tool assembly without pulling the drill pipe out. Casing strength and bottom tool assembly were introduced and the application prospect of casing drilling technology in complex formation of coal mine is discussed.

Abstract:By grouting water from outside the drill pipe, adjusting mud agents and some other methods, drill pipe lubrication, cooling and bit burning were solved for drilling in deep water table coalfield with successful experience. In this paper, the applicability of conventional methods of drilling construction, the adaptability for special cases and breakthrough thinking were interpreted, and the consequent experience and enlightenment were together presented.

Abstract:The effect of leakage stoppage has been affected the drilling speed of brine extraction well of alkali mine in Tongbai of Henan. By the leakage stoppage test with cement grouting in well SP08, it was found that the leakage characteristic of this stratum is fractured loss. Based on this characteristic and according to the laboratory test, a leakage stoppage technology for this region was systematically summed up in choice of leakage stoppage material and technology. A comprehensive technical measure and pressure sealing method mainly with high water loss material matching bridging blockage material was made to provide technical support in this mining area.

Abstract:Drill rod sticking, burying and breaking are common accidents in wire-line coring drilling. Obstacle-avoiding by sidetracking is an ideal choice, accident treating time can be greatly shortened to save the borehole from being abandoned and reduce the loss brought by accident. The paper introduced a case in Chongqing, PDM directional sidetracking was used for obstacle-avoiding branch with success.

Abstract:Drilling in soft and outburst coal seam, the medium pressure air drilling has obvious advantages in technology and supporting equipment. Through the application of this technology in Pingdingshan coalmine, borehole without enough depth, borehole accident prevention and accident treatment difficulties were effectively resolved. The practice showed that the medium pressure air drilling technology is worth popularizing in soft and outburst coal seam drilling.

Abstract:Drilling is the most direct and most correct technical method and is one of the most important means in groundwater pollution survey. The information of underground pollution can be obtained by coring and sampling. The quality of coring and sampling is very important to the authenticity of survey data, so proper sampling methods should be selected according to the different conditions of investigation site and the different purposes of investigation; meanwhile, the operating rules should be strictly followed.

Abstract:According to the simulation analysis and study on failure mode of rock auger， the structure, material and manufacture technology are discussed. The safety wire rope structure is used to improve the strength and the safety factor of rock auger used for the high torque rotary drilling rig. Furthermore, the attentions in manufacture and application of rock auger are mentioned.

Abstract:Because of the demand of rapid well completion in field condition, a pumping device for speedy wall washing was developed. The paper introduced the device about its performance principle, structure characteristics and practice application. Drilling and well washing can be separately operated with high efficiency and convenient operation, the device is suitable to well washing for new and old wells for depth of less than 200m.

Abstract:Rotary air supply and slag removal mechanism for double-tool drilling are the key parts of the power head, and the operation quality of its sealing device is the important guarantee for drilling machine normal operation. The structure forms of flanking and central air supply are described, the choice of sealing elements and structural characteristics of slag removal system are emphatically introduced in this paper.

Abstract:Roadbed settlement prediction method is briefly introduced. According to the sedimentation data in a passenger dedicated line, exponential fitting and hyperbolic fitting were made. By the contrastive analysis on measured data and fitting data, exponential fitting was more accurate than hyperbolic fitting in settlement prediction. Being simpler than all other settlement prediction methods, exponential fitting and hyperbolic fitting are suitable for engineers and technicians.

Abstract:Pile bottom post grouting for friction pile with super long (＞100m) and super large（φ2.5m）was first applied in loose and soft formation in Sutong Bridge construction in China. Based on the engineering practice, the design and key technical points were introduced. By the analysis on the samples, the obvious difference of slurry initial setting time between ground experiment and underground situation was found. According to the slurry diffusion and permeation conditions by sampling, the grouting amount, not the pressure, is taken as control parameter in permeable formation.

Abstract:With the curtain grouting project of Daning regulating reservoir in Beijing, the paper discussed the curtain grouting construction process in detail; according to the complicated geological conditions, the paper also summed up the construction experiences and methods, analyzed the changes of grouting amount per unit and permeability rate in different formations before and after grouting and evaluated the grouting effect.

Abstract:The vertical shaft of Langya Mountain pumped storage power station is 70m in depth, 20m and 18.6m in outer diameter and inner diameter. The consolidation grouting of the shaft was completed by the aid of hoisting system with sinking stage, suspension cage and winch. The grouting work was successfully completed by optimizing the construction scheme, reasonably organizing construction, establishing perfect rules and regulations, strengthening the vocational training and strictly carrying out construction safety measures.

Abstract:The paper presented the application of cone grab in grabbing gravel footage and combining with rotary drilling technology for ultra drilling in bored shaft with diameter of 8.3m and depth of 285m, and introduced the parameter selection for grabbing equipment, grabbing process and the determination of technical parameter.

Abstract:Based on the calculation cases for different formation situations, characteristic value of foundation bearing capacity was calculated by shear strength index thickness weighted average method and additional stress area method. Analysis was made on calculation results, conclusion was drawn that shear strength index should be calculated by additional stress coefficient method. Shear strength index should use non consolidated and non drainage shear ones, when the bearing stratum is of silt, shear strength index should be reduced to 75%.

Abstract:The safety of subway operation must be ensured in the construction of foundation pit support project close to the subway with great difficulty and high safety margin. This paper describes an engineering practice of foundation pit support close to the subway, by the three-demensional numerical analysis, the displacement and stability of the excavation met the design requirement and the weak points were mainly monitored. According to the check calculation on measured values, the measured values were controlled in the range of calculated values.

Abstract:By the study on landslide attitude changing processes and regularity before and after the sudden disaster outbreak, using automatic monitoring and wireless transmission technology, an automatic monitor of landslide attitude and acceleration was developed for geological disasters forecast. The “black box” with data acquisition and storage function was used for tracing monitoring the whole formation process of landslide hazard to realize real-time monitoring of 3d displacement azimuth, velocity and acceleration changes.

Abstract:The construction method of anticorrosion and grouting technology for accumulation body pre-stressed anchor cable was discussed based on the field case of a geological disaster treatment in the side slope of Shilu iron mine in Hainan.