Abstract:By the analysis on the technical problems encountered in the scientific drilling construction in Luobusha of Tibet, the paper elucidates the technical problems that are often encountered in deep drilling construction and need to be carefully considered; summed up the construction experience in complex formations and the countermeasures.

Abstract:Based on the technical material review, analysis was made on foreign sampling tools for gas hydrate in deep sea about the structure principle, technical parameters, operation process, main characteristics and the requirements to the device. Brief introduction was made on the development progress of sampling device during “Eleven Five-year Plan” in China.

Abstract:To make the drilling process more efficient and successful against drilling complex formations while penetrating through deep thick overburden layer at Badi hydropower station over the Dadu river, 139 thick-walled casing and vegetable gum were used to improve coring quality and drilling efficiency respectively. 139 thick-walled casing can avoid frequent drilling accidents and shallow depth in casing process and is compatible with 108 casing much better than 127. It is proved that this technology can give good coring qualityand satisfy drilling efficiency with lower drilling cost and higher economic benefits.

Abstract:With the brief discussion on the status of lost circulation control, the paper introduced the recent scientific research achievements in view of the high-strength fast dehydration plugging, the high-strength chemical thixotropic materials plugging and the swelling plugging materials, as well as the film-forming drilling fluid technology. The paper also presents that the key research directions in the relevance of loss zone characteristics judgment and plugging measures; broad spectrum plugging technology; integration of composite plugging materials and leak-proof technology; high-efficient materials for loss circulation control while drilling and leak-proof washing fluid system; and expansion tubular sealing technology.

Abstract:According to the formation and drilling characteristics in Fujian coalfield, analysis was made on the hazard in drilling leakage; and based on the review of leakage control in Fujian coalfield, the discussion was made on the ideas and the countermeasures for further solutions to complicated drilling leakage.

Abstract:The stratum is complicated in Dabaoshan molybdenum mine. Leakage， block falling， borehole collapsing and diameter shrinkage often occurred and coring was difficult for drilling tool breaking， sticking， bit burning and burying. By selection of rational drilling technologies， wall protection and leakage control methods and drilling coring methods， the detailed survey and prospecting drilling were smoothly completed. The paper introduced the drilling technology in the complex formation of Dabaoshan molybdenum mine.

Abstract:A new method for predicting formation drillablity was proposed according to the theory of BP networks based on PSO. The use of PSO optimizing the parameters of BP networks is to improve the convergence speed and precision of BP neural networks. Combining with the examples of drilling and based on the relationship of log information formation drillability grade, a real-time formation drillability grade model was established. The results show that the model is superior to BP network with higher accuracy and faster convergence rate and it is an effective way to predict formation drillablity.

Abstract:The shape of turbine blade has great impact on the performance of turbodrills. Take the example of turbodrill with diameter of 127 mm for geological drill; it is proposed to determine the configuration of the blade by quintic polynomial. Solidworks 3D modeling software was used in drawing three-dimensional model of the turbine blades. ANSYS FLOTRAN CFD was imported into the model, and hydraulic performances of the turbine blades under different viscosity were analyzed. From this simulation, abundant data of internal flow field have been obtained. Under CFD analysis, it confirms that the defects and hydraulic performance of turbodrill under different conditions are well demonstrated, which has guiding role for prediction of blade hydraulic performance.

Abstract:On the basis of the optimization of structure design for deep hole wire-line coring drill pipe and the selection of high quality steel, rational processing technology and detecting rules are established with relative detecting appliances. By the strict process control, the quality of drill pipe is ensured to satisfy the requirements of wire-line coring drilling.

Abstract:This paper discusses the structural design features of AQK large diameter rock-socketed belled drill, illustrates the adaptability and reliability of this new belled drill and puts forward some requirements to the key problems of belled drill manufacture and construction process.

Abstract:The paper introduced GYZ-1000 grouting auto-recorder, which is used to accurate record the grouting parameters in grouting construction process and can make real-time automatic adjustment on grouting parameters to ensure the grouting construction quality. With “automatic grouting data-processing software system” established in “Construction Specification of Cement Grouting Used for Hydraulic Structures”, the grouting data can be automatically processed in time with high efficiency.

Abstract:The paper studied and discussed the difficult and important points of hadal depth & abnormal shape underground diaphragm wall and inducted 7 key links of construction for hadal depth & abnormal shape underground diaphragm wall. Discussion was made on these 7 issues by engineering case to verify the application effects.

Abstract:Based on the typical deep foundation pit bracing project in soft soil in Wuxi, the application of secondary grouting soil nailed wall for deep foundation pit bracing and construction control were introduced. The bearing capacity of secondary grouting soil nail and settlement & displacement of bracing structure during construction were summed up to analyze and evaluate the economic with the special experiments and monitoring results. It shows that the secondary grouting soil nailed wall is an economical, fast and safe bracing method which can greatly increase the bearing capacity and has no unfavorable influences on the bracing structures.

Abstract:There were various obstacles distributed in the miscellaneous fill in the site of Beijing Spring Garden project, such as old pipes, old foundation concrete, concrete blocks, the soil nails and steel strands of old foundation pit support, and there were also some pipelines near the piles need to be protected, the construction was very difficult. According to the engineering conditions，artificial hole-digging, drilling with long spiral drilling machine and post-insert reinforced cage were adopted in this project. The practice shows that these technologies can not only effectively deal with the shallow underground obstacles and protect the underground pipelines, but also has many advantages of simple and safe construction, high quality reliability and short construction period. The environment problems of slurry pollution and slurry treatment are completely solved with obvious social and economic efficiency. The paper introduced these technologies about the construction process and operation points.

Abstract:The paper introduced the development cause of no embedding fixed supporting pile. The defects of no embedding fixed supporting pile are remedied by other composite support methods (such as anchor and middle beam) to effectively consolidate deep foundation pit for stability and safety. Compared with traditional deep embedding fixed supporting pile, no embedding fixed supporting pile is safe and economical, which is worth popularizing.

Abstract:Dealing with the dam seepage by the grouting technology is a complicated process. According to the application of grouting technology in Shuhe power station, the paper introduces the design idea and the construction method, summarizes the practice rule of the project and the existing problems, puts forward some new ideas about the application of grouting technique and provides some experience for the other similar project construction.

Abstract:The paper introduced the construction technology of consolidation for collapsible soil at pipe end of pre-stressed pipe pile by high-pressure rotary jet pile with an engineering case. When the subsidence of the pile end of pre-stressed pipe pile occurred in bearing stratum of collapsible soil with many restricted conditions for consolidation, the pertinent construction operations, technical processes, technical parameters and the countermeasures were adopted.

Abstract:The height of a high-rise building at core area of Beijing CBD is proposed to be more than 550m, which will be the new landmark building in Beijing. The construction technique of foundation pile is very important to ensure the quality of this skyscraper. The key construction technologies of cast-in-place testing pile is summarized and studied.

Abstract:Evaluation of site and foundation seismic effect plays a significant role in the geological engineering investigation. Based on the engineering geological conditions and geotechnical engineering investigation situation in Tianjin, the key problems existing in the evaluation of site and foundation seismic effect are discussed, including the seismic fortification intensity determination, site classification, classification of seismic section, liquefaction estimation, soft soil subsidence, ground stability and suitability evaluation and so on, in order to give reference to geotechnical engineering industry.

Abstract:According to the pile foundation engineering of 2nd section of Monapo bridge foundation project in Nampula-Cuambaroad road upgrading and regeneration in Mozambique, calculation analysis was made on the stress and reinforcement of different base heights and pile lengths of embedded rock pile of thin walled abutment with Prokon 2.5 structure analysis software, so as to provide the basis for rational selection of pile foundation type based on different formation conditions and base heights in the design.

Abstract:With the continuous standardization in construction market and gradual perfection of various laws and regulations, the sub-contract of tunnel construction is a trend for construction enterprise. Based on the status of implement and management in the projects, analysis was made on the production management and control of tunnel construction, a set of relatively reasonable experiences was summed up to generalize the management of processing organization model of tunnel construction.