The actual situation of the Tisza Valley traditionally used for land farming is basically determined by the consequences of the river regulation of the nineteenth century which aimed at the extension of the intensive ...The actual situation of the Tisza Valley traditionally used for land farming is basically determined by the consequences of the river regulation of the nineteenth century which aimed at the extension of the intensive agriculture, by the extreme water regime of alternating periods of flood showing a deteriorating trend and drought related to the climatic change; and by several environmental problems induced mainly by the land use. The objective of the article is to prove the regional advantages of a proposed technical solution to mitigate the flood risk with a special regard to the land cover. Hydrodynamic modeling results prove that the best technical solution is given by a combination of different strategies containing the inundation of deep floodplains-areas regularly covered by water before the river regulation works and, globally, by an important mitigation of flood damages, the costs of solution would be surely covered in the longterm. By means of its natural-resembling operation, the regular water cover would allow a multiple use of water, contributing to the solution of the simultaneously existing aridity problem, and, the development of the floodplain landscape management would help improve the ecological and the economical upgrading of the region.展开更多
The settlement curve of the foundation endured the ramp load is an S-type curve,which is usually simulated via Poisson curve.Aimed at the difficulty of preferences in Poisson curve,an immune algorithm (IA) is used.IA ...The settlement curve of the foundation endured the ramp load is an S-type curve,which is usually simulated via Poisson curve.Aimed at the difficulty of preferences in Poisson curve,an immune algorithm (IA) is used.IA is able to obtain a multiple quasi-optimum solution while maintaining the population diversity.In this paper,IA is used in an attempt to obtain accurate settlement prediction.The predicted settlements obtained by IA are compared with those predicted by the least squares fitting method (LSM),the Asaoka method and the genetic algorithm (GA).The results show that IA is a useful technique for predicting the settlement of foundations with an acceptable degree of accuracy and has much better performance than GA and the Asaoka methods.展开更多
The constitutive model and equivalent deformation modulus of an arbitrary column in representative elementary volume (REV) of fractured rock mass are derived. The deformation of fractured rock mass is com- posed of ...The constitutive model and equivalent deformation modulus of an arbitrary column in representative elementary volume (REV) of fractured rock mass are derived. The deformation of fractured rock mass is com- posed of the rock part and the fracture part. The elasto-visco-plastic property is considered in this model. For the convenience in engineering practice, the complex elasto-visco-plastic model and its equivalent modulus are degraded, and tbe rock is taken as an elastic body. By statistical analysis of the geometric positions of the column and the fracture, the equivalent modulus of rock mass with arbitrary fractures is obtained.展开更多
文摘The actual situation of the Tisza Valley traditionally used for land farming is basically determined by the consequences of the river regulation of the nineteenth century which aimed at the extension of the intensive agriculture, by the extreme water regime of alternating periods of flood showing a deteriorating trend and drought related to the climatic change; and by several environmental problems induced mainly by the land use. The objective of the article is to prove the regional advantages of a proposed technical solution to mitigate the flood risk with a special regard to the land cover. Hydrodynamic modeling results prove that the best technical solution is given by a combination of different strategies containing the inundation of deep floodplains-areas regularly covered by water before the river regulation works and, globally, by an important mitigation of flood damages, the costs of solution would be surely covered in the longterm. By means of its natural-resembling operation, the regular water cover would allow a multiple use of water, contributing to the solution of the simultaneously existing aridity problem, and, the development of the floodplain landscape management would help improve the ecological and the economical upgrading of the region.
基金Project(No.NCET-06-0649)supported by the New Century Excel-lent Talents in University,China
文摘The settlement curve of the foundation endured the ramp load is an S-type curve,which is usually simulated via Poisson curve.Aimed at the difficulty of preferences in Poisson curve,an immune algorithm (IA) is used.IA is able to obtain a multiple quasi-optimum solution while maintaining the population diversity.In this paper,IA is used in an attempt to obtain accurate settlement prediction.The predicted settlements obtained by IA are compared with those predicted by the least squares fitting method (LSM),the Asaoka method and the genetic algorithm (GA).The results show that IA is a useful technique for predicting the settlement of foundations with an acceptable degree of accuracy and has much better performance than GA and the Asaoka methods.
基金Foundation item: the Western Transport Construction Science and Technology Project of the Ministry of Transport of the People's Republic of China (No. 2009318000046)
文摘The constitutive model and equivalent deformation modulus of an arbitrary column in representative elementary volume (REV) of fractured rock mass are derived. The deformation of fractured rock mass is com- posed of the rock part and the fracture part. The elasto-visco-plastic property is considered in this model. For the convenience in engineering practice, the complex elasto-visco-plastic model and its equivalent modulus are degraded, and tbe rock is taken as an elastic body. By statistical analysis of the geometric positions of the column and the fracture, the equivalent modulus of rock mass with arbitrary fractures is obtained.