Aladdin Alwisy

Integrated BIM/Lean Base Production Line Schedule Model for Modular Construction Manufacturing

Building Information Modeling (BIM) and lean are two distinct concepts used in the construction industry which are independently applied to the construction process and provide profound impacts. Evidence shows potential gain if both BIM and lean are integrated. This research proposes an integrated model that applies both BIM and lean on a modular construction manufacturing (MCM) process and gains the benefits of both concepts. A computer tool for drafting the modular construction process called MCMPro was expanded to generate the building components’ schedule. The Value Stream Map (VSM) of the factory is generated based on the components’ schedule through a proposed Integrated Process Improvement (IPI) method using a set of mix lean principles to reduce waste over a broad range of factory activities. A simulation model using Simphony.NET 3.5 is developed to run the generated VSM and produces the results. The proposed methodology is validated by a case study, which is a modular building located in Edmonton, AB, and illustrates the effectiveness of the proposed methodology.

A BIM-based automation of design and drafting for manufacturing of wood panels for modular residential buildings

ABSTRACT Design and drafting requirements associated with modular construction exceed those of the traditional stick-built method. Man-made errors, design assumptions and onsite interpretations of the shop drawings cannot be tolerated. Therefore, building information modelling (BIM) is needed to facilitate the automation of design and drafting for manufacturing. However, high initial cost, required expertise and limitations of currently available software prevent BIM from realizing its full potentials. This research introduces a systematic methodology for automating the drafting and design for manufacturing of wood-framed panels for modular residential buildings. It utilizes 2D computer-aided design (CAD) drawings to automatically generate BIM and construction manufacturing BIM; subsequently, shop drawings for the wood-framed panels are developed according to the platform framing method. The proposed framework is incorporated into a computer application called MCMPro, which is developed using visual basic application within CAD environment. Reduced design cost, improved layout accuracy and enhanced productivity are expected advances of MCMPro.

Framework for target cost modelling in construction projects

ABSTRACT Target costing (TC) is an effective construction management technique that has been proven to enhance project performance through the evaluation of construction component alternatives that satisfy a desired cost. However, current research focusing on the adoption of TC in the construction industry still follows a manual, time-consuming process. Improvement measures are heuristic and rely on the intuition of designers. This paper proposes a systematic framework, called target cost modeling (TCMd), for the application of TC in the construction industry to automatically generate a detailed project estimate based on a set of client requirements and a desired cost. It uses a three-level database to collect project data and generate a set of available alternatives. Value and compatibility studies govern the process of selecting among alternatives, and mathematical costing models calculate the cost accordingly. Finally, alternative value analysis improves the project value through the use of an optimization method, simulated annealing. TCMd is expected to efficiently improve project performance and enhance the design process while meeting a desired overall cost.

Simulation based multi-objective cost-time trade-off for multi-family residential off-site construction

Off-site construction is a shift toward a more efficient building process in terms of minimizing cost and decreasing duration of projects. However, since off-site construction consists of two separate phases, a comprehensive cost-time trade-off is essential. It gives control for the overall process where the direct and indirect effect of work performed on an individual task can be measured and evaluated with respect to the final project performance factors. The research presented in this paper develops a simulation model to study the dynamic relationship between off-site manufacturing and cost-time trade-off. A multi-objective analysis for two main indirect costs and inventory cost of the manufactured building components are proposed in order to provide a decision support system tool to clarify any ambiguity in the dynamic relationship between the projects two stages, and assist the manager to improve project planning and control.