The displacements and geometry of the rock blocks and the properties of the rock struc-ture play an important role in the stability of tunnels.Based on the key block model,the dynamic instability analysis of undergrou...The displacements and geometry of the rock blocks and the properties of the rock struc-ture play an important role in the stability of tunnels.Based on the key block model,the dynamic instability analysis of underground tunnel subjected to intensive short-time compressional wave was conducted.The instability of the tunnel caused by the spallation and the inertial effect was distin-guished.And the influence of the roof contour curvature of tunnel was also determined.展开更多
In this paper, for a sustainable building in a Mediterranean climate areas, the relation between envelope and energy is discussed. The relation between envelopes and energy has been considered in all the phases of the...In this paper, for a sustainable building in a Mediterranean climate areas, the relation between envelope and energy is discussed. The relation between envelopes and energy has been considered in all the phases of the life building (construction phase and during operation). This has been made through global assessment of massive envelopes (with or without insulation) realized with blocks of different materials: natural stone, concrete and brick. For these types of envelope the thermal comfort of the rooms, the energy requirement for cooling and heating, economic and environmental aspects (costs and embodied energy) in the life cycle of the building have been studied.展开更多
Time and cost are two of the most important factors to consider in each construction project. In order to maximize performance, both the client and the contractor will work to optimize both the duration of the project...Time and cost are two of the most important factors to consider in each construction project. In order to maximize performance, both the client and the contractor will work to optimize both the duration of the project and its cost. We show a model of linear entire mixed programming to solve the considered problem. The aim is to minimize the project total time, by means of the assignment of equipments of work to the different production lines of the activities to realizing. The fundamental beginning is to support the same production (rate of production in meters/day of the activity in view of the equipment of work) for tbe different equipments to achieve the maximum efficiency in each period of time. With the limited availability of resources, the work must be continuous and the period of time between operations and final must be kept. However, this paper also presents the bibliographical study on methodologies of the optimization of construction processes in response to the two objectives: time and cost. This will consider the use of recta-heuristic techniques, such as population based algorithms.展开更多
基金Supported by Beijing Natural Science Foundation and Key Program of Scientific Planning of Beijing Education Committee (No.KZ200810016007)
文摘The displacements and geometry of the rock blocks and the properties of the rock struc-ture play an important role in the stability of tunnels.Based on the key block model,the dynamic instability analysis of underground tunnel subjected to intensive short-time compressional wave was conducted.The instability of the tunnel caused by the spallation and the inertial effect was distin-guished.And the influence of the roof contour curvature of tunnel was also determined.
文摘In this paper, for a sustainable building in a Mediterranean climate areas, the relation between envelope and energy is discussed. The relation between envelopes and energy has been considered in all the phases of the life building (construction phase and during operation). This has been made through global assessment of massive envelopes (with or without insulation) realized with blocks of different materials: natural stone, concrete and brick. For these types of envelope the thermal comfort of the rooms, the energy requirement for cooling and heating, economic and environmental aspects (costs and embodied energy) in the life cycle of the building have been studied.
文摘Time and cost are two of the most important factors to consider in each construction project. In order to maximize performance, both the client and the contractor will work to optimize both the duration of the project and its cost. We show a model of linear entire mixed programming to solve the considered problem. The aim is to minimize the project total time, by means of the assignment of equipments of work to the different production lines of the activities to realizing. The fundamental beginning is to support the same production (rate of production in meters/day of the activity in view of the equipment of work) for tbe different equipments to achieve the maximum efficiency in each period of time. With the limited availability of resources, the work must be continuous and the period of time between operations and final must be kept. However, this paper also presents the bibliographical study on methodologies of the optimization of construction processes in response to the two objectives: time and cost. This will consider the use of recta-heuristic techniques, such as population based algorithms.