The stability of a backfill wall is critical to implement gob-side entry driving technology in which a small coal pillar is substituted by a waste backfill wall. Based on features of surrounding rock structures in the...The stability of a backfill wall is critical to implement gob-side entry driving technology in which a small coal pillar is substituted by a waste backfill wall. Based on features of surrounding rock structures in the backfill wall, we propose a mechanical model on the structural effect of a soft-hard backfill wall using theory analysis, physical experiments and a numerical simulation. The results show thatChe deformation of the structure of the soft-hard backfill wall is coordinated with the roof and floor. The soft structure on the top of the backfill wall can absorb the energy in the roof by its large deformation and adapt to the given deformation caused by the rotation and subsidence of a key rock block. The hard structure at the bottom of the backfill wall can absorb the strong supporting resistance from the top surrounding rock. The soft structure on the top protecting the hard bottom structure by its large deformation contributes to the stability of the entire backfill wall. An application indicated that the stress in the backfill wall effec- tively decreased and its deformation was significantly reduced after the top coal remained. This ensured the stability of the backfill wall.展开更多
Recent estimates state that the European Union is on course to achieve only half of the 20% energy consumption reduction target by 2020. As the first governmental stakeholders involved in the implementation of energy ...Recent estimates state that the European Union is on course to achieve only half of the 20% energy consumption reduction target by 2020. As the first governmental stakeholders involved in the implementation of energy saving initiatives, municipalities play a strategic role in the energy planning process. This paper focuses on establishment of an energy planning methodology for small municipalities with numbers of inhabitants in range of 1,000-10,000 which often face common problems associated with low efficient district heat supply systems and decreasing energy consumption in buildings. Particular attention is paid to DSM (demand side management) activities. DSM scheme includes legislative and financial flows with small investments from municipality side. Based on increased information and motivation it promotes reduction of energy consumption in all kinds of buildings. Practical experience has shown that application of DSM measures allows achieving 20% energy savings in municipal buildings during the first year.展开更多
基金Financial supports for this work, provided by the New Century Excellent Talents in University (No.NCET-05-0480)the Research Fund of the State Key Laboratory of Coal Resources and Mine Safety of CUMT (No.09KF06)the Scientific Research Fund of CUMT (No.OA090239)
文摘The stability of a backfill wall is critical to implement gob-side entry driving technology in which a small coal pillar is substituted by a waste backfill wall. Based on features of surrounding rock structures in the backfill wall, we propose a mechanical model on the structural effect of a soft-hard backfill wall using theory analysis, physical experiments and a numerical simulation. The results show thatChe deformation of the structure of the soft-hard backfill wall is coordinated with the roof and floor. The soft structure on the top of the backfill wall can absorb the energy in the roof by its large deformation and adapt to the given deformation caused by the rotation and subsidence of a key rock block. The hard structure at the bottom of the backfill wall can absorb the strong supporting resistance from the top surrounding rock. The soft structure on the top protecting the hard bottom structure by its large deformation contributes to the stability of the entire backfill wall. An application indicated that the stress in the backfill wall effec- tively decreased and its deformation was significantly reduced after the top coal remained. This ensured the stability of the backfill wall.
文摘Recent estimates state that the European Union is on course to achieve only half of the 20% energy consumption reduction target by 2020. As the first governmental stakeholders involved in the implementation of energy saving initiatives, municipalities play a strategic role in the energy planning process. This paper focuses on establishment of an energy planning methodology for small municipalities with numbers of inhabitants in range of 1,000-10,000 which often face common problems associated with low efficient district heat supply systems and decreasing energy consumption in buildings. Particular attention is paid to DSM (demand side management) activities. DSM scheme includes legislative and financial flows with small investments from municipality side. Based on increased information and motivation it promotes reduction of energy consumption in all kinds of buildings. Practical experience has shown that application of DSM measures allows achieving 20% energy savings in municipal buildings during the first year.