BIM workflow for pre-construction constructability evaluation using 4D tasks

Planiranje in izdelava terminskih planov gradbenih projektov so odvisni od tehnoloških in časovnih omejitev aktivnosti gradbenih del v določenem časovnem oknu, lokaciji in specifičnih zahtevah. Omejitve določajo proces izvedbe gradbenih del in medsebojne odvisnosti, ki se pojavljajo pri izvajalskih delih. Aktivnosti izvajalskih del določajo in zahtevajo ekskluzivni dostop do določenih področij na gradbišču. Razpoložljivost prostora na gradbišču je odvisno od napredovanja gradbenih del. Ko se te omejitve, povezave in odvisnosti med aktivnosti ne upošteva, potreben prostor za izvedbo gradbenih del ni ustrezno upoštevan pri terminskem planiranju, lahko povzročijo neusklajeno izvedbo in nepredvidljive zastoje in dodatne stroške. Običajno se uporablja terminsko planiranje z diskretno simulacijo elementov informacijskih modelov stavb. Dodatne podrobnosti, kot so organizacija gradbišča, uporabljena oprema, začasne konstrukcije in drugi viri, so komplementarni informacijam informacijskih modelov, in so nujno potrebni za bolj natančno terminsko planiranje. Ta raziskava se osredotoča na razjasnitev omejitev in na določitev Za učinkovito simulacijo izvedbe potrebujemo ustrezne podatke, ki jih pridobimo iz informacijskih virov kot so modeli zgradb, deležniki, vodje gradbišč, standardnih tabel, in jih nadgradimo s dodatnimi informacijami o procesih. Priprava podatkov, njihova integracija in simulacija je izvedena s pomočjo interaktivnega pripomočka za simulacije, uvoza preglednic, in kasneje izvedemo presojo procesov za simulacijo, ki omogočajo nadgradnjo modela s potrebnim prostorom za aktivnosti. Model aktivnosti, ki je določen z aktivnostmi škatlami, ki določajo potreben prostor za aktivnosti. Simluacija kolizij med škatlami aktivnosti omogočajo projektnim vodjem, da identificirajo težave pri izvedbi, tudi z uporabo BIM na gradbišču.The planning and scheduling of construction projects depends on technological and temporal constraints of construction activities within the frame of time, location, specific requirements, etc. The constraints determine the construction processes and their relationships that result in construction activities. Then, the construction activities define and require exclusive access to certain spaces at the construction site. Availability of these spaces often depends on the progress of construction. When these constraints, relationships and dependencies and their required spaces are not adequately considered for construction scheduling and during the process, they may cause conflicts at the construction site with the consequences of incalculable delays and extra costs. Nowadays, construction scheduling can be supported by discrete event simulation based on building information models (BIM). Yet further details from construction site plan and equipment and resources are required to compliment the information provided by building information models and required for construction scheduling. The focus of this research is on the clarification of constraints and suggest an efficient construction workflow in BIM. For an efficient construction simulation, data has to be extracted from underlying data resources like models, stakeholders, project managers, standard tables, etc. and enhanced with additional process information. Data preparation and its integration with the building model into simulation is done with the aid of an interactive mediator for construction simulation resulting in an activity loaded model. The activity model has task-boxes surrounding building elements representing the required space for the activities to construct each element in the building. Later, an evaluation process for the simulated construction activities to their optimization are held by assessing the in-task clashes among simulated activities (Marx and Markus König, 2011). This evaluation can alert project managers on the workflow and requirements of the construction site at pre-construction phase. In fact, constructability of the project is being organised by BIM-on-site