The paper examines the situation and causes of recent big earthquake and tsunami disasters especially in the case of the Great East Japan Earthquake in 2011, and analyzes the damage to extract lessons on safety of bui...The paper examines the situation and causes of recent big earthquake and tsunami disasters especially in the case of the Great East Japan Earthquake in 2011, and analyzes the damage to extract lessons on safety of buildings and recovery of cities from the view point of building regulations such as the Article 39 of the Building Standard Law. In addition, the Article 8 of the Ordinance of City Planning Law resulted in not so effective against tsunami in March 2011. Control mechanisms of building construction should be integrated into socio-economic, institutional, technical and other policy tools. In order to mitigate earthquake risk, all stages of building construction, from location, planning and construction to maintenance are important. Awareness creation is instrumental for building culture of safety and demands for intervention in disaster mitigation. The demands ultimately help in creating conducive environment for policy intervention, in realizing institutional mechanism of building code enforcement and land use control for the municipal authorities and in creating demand for competent professionals.展开更多
In the process of city construction, as a comprised factor of city geological environment, underground water takes the most active part, and its dynamic change is fiercest. The city construction unceasingly disturbs u...In the process of city construction, as a comprised factor of city geological environment, underground water takes the most active part, and its dynamic change is fiercest. The city construction unceasingly disturbs underground water chemical, dynamical, physical and biological field. In return, the four fields＇ changes also can affect the geological environment that city lived by, in other words they affect safety and stability of geological environment. Interaction of underground water and the geoenvironment directly displays in the following two ways： The first is that the underground water and the geological body transfer the energy each other; the second is that the strength balance of geological body is broken. Underground water variation brought about by city construction is the factor which cannot be neglected. Underground water variation on the one hand changes soils or rocks＇ physical, biological, chemical and mechanical properties, then influences the deformation and strength of geological body. On the other hand it changes its own physical, chemical properties and biochemical component. At present, from mechanics aspect, interaction between chemical field and biological field variation of the underground water and the geological body lacks research. Although interaction between them is long-term, slow, but when it compared with water-soil or water-rock interaction in the entire process of formation of rocks or soils or geologic evolution history, the qualitative change of the biological and chemical action of rocks or soils brought about by city construction is remarkable, in this paper, aiming at underground water biological field factor which is easily neglected by people, it analyzes that underground water biological field affects possible mechanism and approach of properties variation of rocks or soils in city construction, brings forward further research method and development direction have been also proposed.展开更多
This paper tries to comprehensively summarize the reasons of damages at the Great East Japan Earthquake on March 11, 2011 and what are the lessons in terms of earthquake and tsunami safety of building and cities. The ...This paper tries to comprehensively summarize the reasons of damages at the Great East Japan Earthquake on March 11, 2011 and what are the lessons in terms of earthquake and tsunami safety of building and cities. The paper examines the damage of tsunami affected areas and analyses the damage to extract lessons in order to safely reconstruct the affected areas from the view point of building regulations such as ＂Disaster Risk Area＂ provided by the Article 39 of the Building Standard Law and the Urbanization Control Area and UPA （Urbanization Promotion Area） provided by the Article 8 of the Ordinance of the City Planning Law of Japan.展开更多
Tunnel collapse presents a serious threat to the safety of urban construction. The traditional approach adopted to assess this risk is to evaluate the factor of safety against failure. However, this analysis only dete...Tunnel collapse presents a serious threat to the safety of urban construction. The traditional approach adopted to assess this risk is to evaluate the factor of safety against failure. However, this analysis only determines on whether the tunnel will collapse or not, and does not provide information on the magnitude of the post-failure behavior(for example, catastrophic or progressive) if the tunnel collapse occurs. In this study, a meshless method based on the material point method(MPM) was used to investigate the post-failure behavior of tunnel heading collapse in two-dimensional plane-strain conditions. The capability and accuracy of MPM were verified by comparing the elicited results to centrifuge test data and to analytical solutions obtained from limit state methods. MPM simulations were conducted at different soil conditions(clay or sand) and profiles(homogenous or linear increasing strength) as well as at different tunnel geometries(i.e. tunnel depth and unlined length). The differences in the post-failure behavior and mechanisms are examined and reported.展开更多
文摘The paper examines the situation and causes of recent big earthquake and tsunami disasters especially in the case of the Great East Japan Earthquake in 2011, and analyzes the damage to extract lessons on safety of buildings and recovery of cities from the view point of building regulations such as the Article 39 of the Building Standard Law. In addition, the Article 8 of the Ordinance of City Planning Law resulted in not so effective against tsunami in March 2011. Control mechanisms of building construction should be integrated into socio-economic, institutional, technical and other policy tools. In order to mitigate earthquake risk, all stages of building construction, from location, planning and construction to maintenance are important. Awareness creation is instrumental for building culture of safety and demands for intervention in disaster mitigation. The demands ultimately help in creating conducive environment for policy intervention, in realizing institutional mechanism of building code enforcement and land use control for the municipal authorities and in creating demand for competent professionals.
基金Acknowledgments： This work is keystone items of Ministry of Education P.R.C （No. [2003]77）, National Natural Science Foundation of China （No. 40062002）, Natural Science Foundation of Guangxi （Nos. 0447001, 0249010, 0575019, 0779012, 0632006-1B, RC2007001） and Department of Water Resources of Guangxi （No. [2004]4）.
文摘In the process of city construction, as a comprised factor of city geological environment, underground water takes the most active part, and its dynamic change is fiercest. The city construction unceasingly disturbs underground water chemical, dynamical, physical and biological field. In return, the four fields＇ changes also can affect the geological environment that city lived by, in other words they affect safety and stability of geological environment. Interaction of underground water and the geoenvironment directly displays in the following two ways： The first is that the underground water and the geological body transfer the energy each other; the second is that the strength balance of geological body is broken. Underground water variation brought about by city construction is the factor which cannot be neglected. Underground water variation on the one hand changes soils or rocks＇ physical, biological, chemical and mechanical properties, then influences the deformation and strength of geological body. On the other hand it changes its own physical, chemical properties and biochemical component. At present, from mechanics aspect, interaction between chemical field and biological field variation of the underground water and the geological body lacks research. Although interaction between them is long-term, slow, but when it compared with water-soil or water-rock interaction in the entire process of formation of rocks or soils or geologic evolution history, the qualitative change of the biological and chemical action of rocks or soils brought about by city construction is remarkable, in this paper, aiming at underground water biological field factor which is easily neglected by people, it analyzes that underground water biological field affects possible mechanism and approach of properties variation of rocks or soils in city construction, brings forward further research method and development direction have been also proposed.
文摘This paper tries to comprehensively summarize the reasons of damages at the Great East Japan Earthquake on March 11, 2011 and what are the lessons in terms of earthquake and tsunami safety of building and cities. The paper examines the damage of tsunami affected areas and analyses the damage to extract lessons in order to safely reconstruct the affected areas from the view point of building regulations such as ＂Disaster Risk Area＂ provided by the Article 39 of the Building Standard Law and the Urbanization Control Area and UPA （Urbanization Promotion Area） provided by the Article 8 of the Ordinance of the City Planning Law of Japan.
基金supported by China Postdoctoral Science Foundation(Grant No.2014M561186)the National Basic Research Program of China("973"Project)(Grant No.2010CB732106)+1 种基金the National Natural Science Foundation of China(Grant No.51308389)the Tianjin Research Program of Application Foundation and Advanced Technology(Grant No.14CQNJC07500)
文摘Tunnel collapse presents a serious threat to the safety of urban construction. The traditional approach adopted to assess this risk is to evaluate the factor of safety against failure. However, this analysis only determines on whether the tunnel will collapse or not, and does not provide information on the magnitude of the post-failure behavior(for example, catastrophic or progressive) if the tunnel collapse occurs. In this study, a meshless method based on the material point method(MPM) was used to investigate the post-failure behavior of tunnel heading collapse in two-dimensional plane-strain conditions. The capability and accuracy of MPM were verified by comparing the elicited results to centrifuge test data and to analytical solutions obtained from limit state methods. MPM simulations were conducted at different soil conditions(clay or sand) and profiles(homogenous or linear increasing strength) as well as at different tunnel geometries(i.e. tunnel depth and unlined length). The differences in the post-failure behavior and mechanisms are examined and reported.
