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The existing reservoir stimulating technologies are only applicable to hard coal but helpless for soft coal, which is one of the main factors hindering the CBM industrialization in China. Therefore, it is urgent to develop a universal stimulating technology which can increase the permeability in various coal reservoirs. Theoretical analysis and field tests were used to systematically analyze the mechanical mechanisms causing the formation of various levels and types of fractures, such as radial tensile fractures, peripheral tensile fractures, and shear fractures in hydraulic fracturing, and reveal the mechanism of permeability enhancement by fracture network stimulating in surrounding beds and coal reservoirs. The results show that multi-staged perforation fracturing of horizontal wells, hydraulic-jet staged fracturing, four-variation hydraulic fracturing and some auxiliary measures are effective technical approaches to fracture network stimulation, especially the four-variation hydraulic fracturing can stimulate the fracture network in vertical and cluster wells. It is concluded that the fracture network stimulating technology for surrounding beds has significant advantages, such as safe drilling operation, strong stimulation effect, strong adaptability to stress-sensitive and velocity-sensitive beds, and is suitable for coal reservoirs of any structure. Except for the limitation in extremely water-sensitive and high water-yield surrounding beds, the technology can be universally used in all other beds. The successful industrial tests in surface coal bed methane and underground coal mines gas extraction prove that the theory and technical system of fracture network stimulating in surrounding beds and coal reservoirs, as a universally applicable measure, will play a role in the CBM development in China.

This paper presents the results of shear tests on 27 self-stressing concrete filled steel tube (SSCFST) specimens and 8 conventional concrete filled steel tube (CFST) specimens. The main parameters in the tests were the self-stress and shear span to depth ratio. The experimental results indicate that the shear capacity of the CFST specimen is lower than that of the SSCFST specimen when 28-day cube strength of concrete core, shear span to depth ratio, yield strength and geometrical dimension of the steel tube are kept the same. The CFST/SSCFST specimen failed in shear when the shear span to depth ratio was smaller than 0.5 and failed in flexure when the shear span to depth ratio was 0.5 or higher. The bond between concrete core and steel tube also affected the shear capacities. Finally, an empirical equation for predicting the shear capacity of a SSCFST short beam is proposed.

Examination is currently a main and also a direct-viewing means for testing students. The development in intelligent system configuring test questions in date-base appears especially important. The theory in the construction of date-base and its realization principles are analyzed in this paper, combined with the situation of separation from teaching and examination in Henan Polytechnic University. The main technology and method are discussed about the outline and organization structure of the date-base and the intelligent configuration of test questions and the system realization. The configuration of test questions system is developed with the web, which is based on the B/S mode, adopting the hierarchical control pattern and Object-Oriented method. According to ASP +Java+MYSQL and other technologies, we solve the problems of poor efficiency in extracting and making test questions and inquiring answers in the past.

The coal layer's gas permeability coefficient is an important index to judge wether it is easy for the gas drainage. The radial flow method is the most common testing way for the coal layer's gas permeability coefficient calculation the current. However, its calculation process is tedious. And sometime could not find the right calculation formula during the calculation. At times, it turns out two results during the calculation. According to the coal bed gas flow theory, combined with the outlier's processing method, using the VB language to develop a software for the coal layer's gas permeability coefficient. Using this software, it can realize the accurate and rapid calculation for the coal layer's gas permeability coefficient.

In order to shorten route and increase road grade, tunnel excavation road scheme will be widely used in mountain area, so tunnel stability will increasingly become important problem for design and construction. In this paper mechanical behavior of tunnel is simulated by FLAC during road tunnel excavation and support with three-dimensional Fast Lagrangian Method. It indicates through numerical simulation that regularities of distribution of displacement and stress in wall rock and supporting structure can be obtained in dynamic excavation by steps and support by steps; at the same time distribution and failure mechanism of plastic zone of wall rock is given about three different phases of without support, first support, second support.