检索结果-南通市图书馆

Lateral Stress Concentration in Localized Interlayer Rock Stratum and the Impact on Deep Multi-Seam Coal Mining

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Geosciences 2013年第9期4卷 1248-1255页

作者： Mingwei Zhang hideki shimada Takashi Sasaoka Kikuo Matsui Department of Earth Resources Engineering Faulty of Engineering Kyushu University Fukuoka Japan

To explore the impact of lateral stress concentration in interlayer rock stratum on the exploitation of protected coal seam, a field experiment was carried out in a multi-seam mining structure. Lateral stress redistribution and interlayer rock failure behavior were surveyed. Then an assistant numerical investigation was implemented to evolve the effect of liberated seam mining and its influence on stress reconstruction in surrounding rock mass. The cause of lateral stress concentration and its impact were discussed finally. Key findings turn out that a certain lateral stress increases in interlayer rock stratum and concentrates on its lower region. Lateral stress concentration and interlayer rock failure are interactional. The former is an inducing factor of the latter;the latter promotes the increase of concentration degree. Extent of lateral stress concentration increases to the maximum as seam distance is about 50 m. But the efficacy of liberated seam mining decreases as the seam spacing gets larger. Protected seam mining is then classified based upon the impact of lateral stress concentration, which helps to prevent the rock burst hazard and then to achieve a reliable mining in deep mines.

关键词： Lateral Stress Concentration Interlayer Rock Stratum Multi-Seam Coal Mining Stress Relaxation Zone Floor Failure Behavior

Development of Flash Setting Material for Temporally Pipeline Restoration after Earthquake

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Geology 2013年第2期3卷 94-100页

作者： hideki shimada Akihiro Hamanaka Takashi Sasaoka Kikuo Matsui Department of Earth Resources Engineering Kyushu University Fukuoka Japan

There are many earthquakes in Japan. If a large earthquake were to occur, it is necessary to consider how pipelines such as: gas, sewage, telecommunications, and so on are restored quickly. At that time, damaged gas pipelines are very dangerous because fire in large areas could be caused by the leakage of gas from the damaged pipeline. Accordingly, it is necessary for gas companies to stop the supply of gas to houses over a large area. Once the gas supply is stopped, there is a considerable amount of time to repair the pipelines over the area. For this reason, a quick method for restoring damaged gas pipelines would be useful after an earthquake. Recently, we have been developing new flash setting material for the damaged gas pipeline by an injection into the house connection of gas when the gas supply is stopped quickly in an emergency. From these points of view, in order to clarify to what degree the contents of flash settling material affect the properties of the injected fly ash mixture causing heavy damage to the gas pipeline in an earthquake, different combinations of fly ash, chemical agents and water were considered in several experiments.

关键词： Flyash Surfactant Injection Material Offshore Structure

Behavior of Surrounding Soil during Construction and Its Countermeasures Using Pipe Jacking Method in Deep Strata

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Geology 2013年第2期3卷 44-48页

作者： Takashi Senda hideki shimada Takashi Sasaoka Kikuo Matsui Department of Earth Resources Engineering Kyushu University Fukuoka Japan

In Japan when urban infrastructures need to be constructed, the difficulty of utilizing the ground or shallow strata will lead to a more frequent use of the deep strata. The common construction methods are open-cut, pipe jacking, and shield methods. In recent years, a new pipe jacking method has been established that can be adapted to 20 m below the ground or more. Using this method, the drivage machine and the jacking pipe continue to move an underground until the completion of the driving. Therefore an over-cutting area (so-called tail-void) must be formed to lower the friction between the ground and the pipe. The tail-void is filled with lubrications. However, because the stress release from the ground continues to advance when the tail-void is formed, hence there are some challenges required to cope with the stability of the surrounding ground. In order to utilize the pipe jacking method in the deeper strata layers, the theory, analysis and installation of tail-void have to be systemized, and such systematic data must be stored. Therefore, the conditions of tail-void in the deep pipe jacking method are discussed using numerical analyses.

关键词： Pipe Jacking System Deep Strata Tail-Void

Feasibility of Chain Conveyor Cutter for Ocean Disposal Site＇s Construction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Geological Resource and Engineering 2017年第4期5卷 169-177页

作者： hideki shimada Sugeng Wahyudi Takashi Sasaoka Akihiro Hamanaka Shizuo Ikuta Department of Earth Resources Engineering Kyushu University Fukuoka 819-0395 Japan Land Creative Co. Ltd Omuta 837-0927 Japan

The concept of ocean disposal site is proven technology. One of the most concerns in ocean disposal site is the leakage ofpollutants into the ocean from waste materials. In order to prevent its happening, technically, a vertical impermeable wall is constructedaround the disposal site. However, the conventional method fails to guarantee zero leakage due to method＇s limitation. This paperpresents the use of CCC （chain conveyor cutter） method to construct vertical impermeable wall. The feasibility of CCC for oceandisposal site is evaluated by means of pollutant dispersion model, and moreover, the result is compared with conventional method. Theresult indicates that the CCC method is technically feasible for ocean disposal site＇s construction. Additionally, this method showsbetter as for technique and economic point of view than that of the conventional method. One of advantage of CCC method is the abilityto construct homogeneous wall in regard to strength and permeability, which cannot be found in the conventional ocean disposaltechnology.

关键词： Chain conveyor cutter ocean disposal soil improvement.

Optimization of Dump Bench Configuration to Improve Waste Dump Capacity of Narynsukhait Open Pit Coal Mine

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Geosciences 2018年第6期9卷 379-396页

作者： Tsedendorj Amarsaikhan hideki shimada Sugeng Wahyudi Takashi Sasaoka Akihiro Hamanaka Department of Earth Resources Engineering Kyushu University Fukuoka Japan

In next two years, the current waste dump of Narynsukhait coal mine is predicted insufficient to accommodate the overburden as limited of the waste dump capacity. Thus, redesigning waste dump is paramount to increase capacity of the dump in future. This paper describes current condition of waste dump of Narynsukhait coal mine and then discusses the optimization of waste dump geometry by analyzing the effect of different waste dump’s bench configuration on slope performance. Optimization of the geometry is carried out by investigating and comparing the performance of geometrical combinations of bench height, bench angles and number of safety berm by means of numerical modeling. The model shows that increasing height of bench is able to induce shear stress in the bench and may initiate bench instable. However, the shear stress can be limited by having safety berm and/or reducing bench angle to satisfy the stability criteria.

关键词： Waste Dump Bench Stability Bench Configuration Open Pit Coal Mine

Numerical Study on Effect of Longwall Mining on Stability of Main Roadway under Weak Ground Conditions in Indonesia

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Geological Resource and Engineering 2017年第3期5卷 93-104页

作者： Phanthoudeth Pongpanya Takashi Sasaoka hideki shimada Akihiro Hamanaka Sugeng Wahyudi Department of Earth Resources Engineering Faculty of Engineering Kyushu University 744 Motooka Nishi-ku Fukuoka-shi819-0395 Japan Department of Mining Engineering Faculty of Engineering National University of Laos Lao-Thai Friendship Road Vientiane3166 Lao PDR

Countermeasure Method for Stope Instability in Crown Pillar Area of Cut and Fill Underground Mine

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Geosciences 2016年第3期7卷 280-300页

作者： Tri Karian hideki shimada Takashi Sasaoka Sugeng Wahyudi Deyu Qian Budi Sulistianto Department of Earth Resources Engineering Kyushu University Fukuoka Japan Department of Mining Engineering Institut Teknologi Bandung Bandung Indonesia

Maintaining stability as well as optimizing recovery of crown pillar, a pillar separating surface area with the uppermost stope in overhand cut and fill underground mining method, is important. Failures in stope may lead to crown pillar failures and cause surface subsidence. Increasing crown pillar thickness will increase crown pillar stability yet reduce mining recovery because part of crown pillar is formed by ore body. Preventing stope failure is the key to maintain stability and optimize recovery of crown pillar. Therefore, it is important to study countermeasure method for stope failure especially in crown pillar area. An attempt has been made to investigate the effectiveness of various countermeasures for stope failure in crown pillar area by means of parametric study. The result shows active type support system is effective for supporting stope in high vertical stress condition while the passive one needs to be installed if the stope is opened in high horizontal stress condition. In general, more supporting capacity from both type support systems is needed if the stope is opened in more severe geological condition. Another countermeasures, sill pillar and surface pile, are introduced for stope instability in crown pillar and non-crown pillar area. Sill pillar is an abandoned slice of unstable stope based on stability analysis. Sill pillar is very effective to stabilize stope both in crown pillar and non-crown pillar area, especially for stope in high horizontal stress condition. Sill pillar application in model with stress ratio 2 can optimize 20 meter thickness of crown pillar into 5 meter. Another proposed countermeasure is surface pile. Surface pile can be installed from the surface to improve stability of crown pillar and stope. The most effective use of surface pile is found in simulation of model with stress ratio 0.75 where surface pile can optimize 15 meter thickness of crown pillar into 5 meter.

关键词： Crown Pillar Stope Stability Active and Passive Type Support System Sill Pillar Surface Pile

Influence of Stope Design on Stability of Hanging Wall Decline in Cibaliung Underground Gold Mine

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Geosciences 2013年第10期4卷 1-8页

作者： Purwanto hideki shimada Takashi Sasaoka Ridho K. Wattimena Kikuo Matsui 1Department of Earth Resources Engineering Faculty of Engineering Kyushu University Fukuoka Japan 2Department of Geology Engineering Mining Engineering Study Program Hasanuddin University Makassar Indonesia Department of Earth Resources Engineering Faculty of Engineering Kyushu University Fukuoka Japan Department of Mining Engineering Faculty of Mining and Petroleum Engineering Bandung Indonesia

Cibaliung Underground Gold Mine applies cut and fill mining method to optimize ore production and maintain underground stability. Existing 5 m × 5 m height and width of stope geometry has a potential new design to increase production of gold due to variety of thick ore, however serious shotcrete failures often occur in hanging wall decline. This paper aims to find out the relationship between stope design and stability of hanging wall decline. The analysis conducted in this study is based on underground characteristics and geological condition of Cibaliung area. The impact of stope design on decline stability was analyzed by using numerical methods. The impact factors such as different rock mass, size of stope, and distance between stope and hanging wall decline were used in the analysis of underground stability especially stability on hanging wall decline.

关键词： Stope Hanging Wall Decline Cut and Fill Cibaliung

Soil Erodibility Characteristics of Reclamation Area--A Case Study in Indonesian Coal Mining

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Civil Engineering and Architecture 2014年第7期8卷 855-859页

作者： hideki shimada Sri Maryati Akihiro Hamanaka Takashi Sasaoka Kikuo Matsui Department of Earth Resources Engineering Faculty of Engineering Kyushu University Fukuoka 8190395 Japan Faculty of Mathematics and Natural Sciences Universitas Negeri Gorontalo Gorontalo 96128 Indonesia

Soil erosion is one of the most important problems in Indonesia coal mining reclamation area because located in tropical areas which has high average of rainfall. Severe soil erosion leads to the unsuccessful reclamation progress in the post mine surface due to impact on steep slope and limit of seedling establishment. Considering the impact of soil erosion in mining activities, Indonesian government had issued several regulations related to erosion control. Soil erodibility is one of the main factors controlling soil erosion. It will determine amount of soil loss and total sediment. Estimation of soil erodibility aims to determine the susceptibility of soil to be eroded by water. The estimation considers soil texture, percentage of organic matter, soil structure and soil permeability. This study was integration between field work to collect soil sample, soil laboratory analysis, soil erodibility analysis using erodibility equation Wischmeier and Smith (1978) and analysis to predict soil erosion/ annual total soil loss. The results show that soil erodibility in study area was calculated to range from 0.091 to 0.142 tons ha h/ha/MJ/mm and soil erodibility of the study area was categorized as very low and low. There are strong relationships between soil erodibility and soil erosion but the correlation was not fully linier due to other factors controlling soil erosion / annual total soil loss.

关键词：土壤可蚀性复垦区印尼煤矿水土流失治理土壤侵蚀特征土壤流失