Several researchers have attempted to formulate and solve different classes of the earthwork allocation problem. Linear programming (LP) and integer programming (IP) techniques have traditionally been applied to minimize transportation costs and mass-haul distances associated with earthwork processes. However, typical formulations of the earthwork allocation problem do not consider the sequence of equipment movement and are, therefore, limited in their ability to establish a practical and workable hauling plan. A more complex problem, which is formulated and solved in this research, is the least-cost route cut and fill problem (LCRCFP). The primary objective of the LCRCFP is to determine the specific route to be traveled and the quantities of soil that construction equipment must haul to meet the desired grade while minimizing the total distance traveled. In this research, the LCRCFP was formulated as a mixed binary optimization problem and solved using a traditional branch-and-bound method and a ...

One of the main applications of building information modeling (BIM) in the construction management process is estimating. BIM has proven to offer great advantages over traditional estimating methods. There are, however, many estimating methods using BIM and the literature on the accuracy and precision of each of the BIM modeling methods remains scarce. Moreover, data on the actual benefits of utilizing BIM in terms of time and cost savings remain fairly limited and are hard to collect from companies in the field. In this paper, data collected over the course of two years in a graduate construction course where BIM is taught for the purpose of costing and estimating are analyzed and presented. The paper first discusses the various techniques that could be used for BIM estimating and then presents the results of an experiment designed to assess the accuracy, effort, and cost of each of the various estimating techniques. This is a pioneering paper, which for the first time quantifies the benefits of ...

Green-roofs are becoming a popular breathing roofing alternative to traditional roofing systems. Green-roofs were mentioned as an ecological-economical solution; however, limited work has been carried out on the potential life cycle cost savings of green roofs in arid climates. This paper present costs savings by green roofs in arid climates. The model accounts for energy savings, structural considerations as well as other variables. Detailed thermal simulations for various configurations of green roofs are performed to assess energy savings using DesignBuilder. Experiments are performed for a two story residential building in Egypt with a base case control that uses a traditional roof meeting standard model energy codes. One local sub-climatic zone was simulated while changing the thickness of the green-roof soil, the conductivity of the green roof and building aspect ratio. Costs for green-roof saving potentials were estimated according to Egyptian electricity consumption calculator, other parameters as retrofit potential and structure allowances to withhold the required layers with different thicknesses. The results demonstrate the economic benefits of using green-roofs under different design situations and provide guidance for the selection and design of green-roofs systems in similar climates. Savings varied from 15-32% compared to traditional and un-isolated roofs. It was also found that reducing soil thickness to 15 cm results in 15% annual savings, Moreover, conductivity of soil has significant impact on amount of savings. The research shows that the most energy saving realized when the aspect ratio of the building is 1:1.5.

Modeling and simulation of dynamic systems has been commonly used in the context of transportation, urban planning, and land use as being the basic tool for planners and policy makers. Vehicular movement modeling is one of the most popular models that deal with relevant aspects of urban regions and communities. This paper focuses on a particular mobility system; electric vehicles (EVs) clusters. It presents a study was conducted to simulate EVs population of the inner urban core of Newcastle-Gateshead via a developed 2D simulation model. The novelty of this study is the new approach proposed to simulate EV population in particular vicinity. This is by utilizing hybrid simulation technique (agent based modeling and discrete events) while applying space syntax theory and principles to predict the travel demand pattern of the urban system. The combination of these layers of modeling within the context of electrical mobility has proven successful in portraying the population and showed promising results. It aims at providing guidelines and recommendations to locate preliminary charging points and determine their numbers and capacities, which should be of interest for researchers, planning authorities and policy makers. This paper is a part of an EU project that focuses on simulating a part of the North Sea Region e-mobility system.