2019 CSCE Annual Conference - Laval (Greater Montreal) Conference
Dr. Amin Hammad
4D simulation is commonly used in building construction projects as part of Building Information Modeling (BIM) processes. Recently, the concepts and methods used in BIM and 4D simulation have been extended to civil infrastructure projects (e.g. roads and bridges) under the umbrella of Civil Information Modeling (CIM). CIM can be further extended to represent the sequence of excavation and mining operations in 4D simulation, where excavation blocks are represented as volumetric parts. The dimensions of the blocks are selected based on the drilling equipment and dynamite capacity while taking into account the sequencing of the crew, safety issues, and the natural slope of the bedrock.
This paper aims to evaluate the applicability of 4D simulation in rock excavation projects to determine the feasibility of the excavation methods and analyse the operational features of the construction site. The developed methodology integrates 3D modeling and visualization techniques with a rock excavation simulation that was validated in an actual construction project. The rock excavation operations that can be evaluated with the 4D simulation include drilling (precut and mass), explosives loading into boreholes, blasting, scaling, anchors installation, rock injection and mocking. The details of loading, hauling and rock explosion operations are not included in the current simulation and will be added in the future. The relevant geological features which influence the spatial distribution of excavation operations (e.g. faults, the quality and type of the rock for the sizing of blocks) are considered in the 3D model. In addition, the site layout is modeled including the original ground level and the ramps made from back-fill or untouched rock. The main challenge of the 4D simulation is sequencing equipment and crews for a feasible schedule without spatio-temporal clashes, while respecting safety considerations (i.e. blast pattern, equipment protection, and distances) and other constraints. The resulting 4D simulation can be used to help the decision making of an integrated team of geologists, engineers and construction managers.
A case study was used to evaluate the proposed method. The developed 4D simulation has a high level of detail (LOD) including 722 parts in the 3D model and a schedule with average task duration of 1.5 days. This LOD is needed for reflecting operational constraints with a predefined list of equipment (excavators and trucks). The 4D simulation has proven helpful by establishing a sequencing strategy where the parts are representing mining blocks.