BIM methodology is not only intended to apply to the executive phase of the project but rather its great advantage lies in the application throughout its life cycle. Let's talk about how we can take advantage of BIM methodology at the stage of 'tendering' or 'Estimating'. To put us imagine a real case, one of the major works at the national level is currently being tendered. The project is mostly metal.
Given the complicated economic situation, in any process of 'tendering' companies in our sector should be focused the flexibility to respond quickly, economically and simultaneously adjusted to provide improvements to the project. We are also constantly thinking about how we can better service each time, without necessarily have to pass it on to the final costs.
are received, as is usual in such cases, a large collection of project plans, fairly complete in this case. The focus of economic study is addressed as follows:
Initially a senior structural designer is responsible for analyzing all the graphic information in order to build a 3D model. The tool used is Tekla Structures. The modeling is done relatively quickly, using their own planes as pdf or CAD drawings linked to the model. It is as if we used these planes linked to 'draw up'.
When the model is advanced (1 or 2 days) the head of engineering, together with a calculation engineer supervise the same, identifying the difficulties and benefits of designing, analyzing the possible loss of unions and detecting the different manufacturing processes needed to carry out the production of the metal structure. 4 days
A structural model is completely finished. From the same are obtained detailed measurements of all elements for evaluation (MAT) and key figures that affect the cost of labor (LABOR). These figures are basically: linear feet of welding, painting surfaces, number of drills, weight of the elements , etc.
Through internal databases of production are obtained fairly automatic cost prices for each of the items from the sum of concepts:
MAT + WORK = COST
Unless structures are extremely unique, the cost price is clearly established, without contingencies arising from an incorrect assessment of the weight of the structure, or the difficulty of it. It is only matter of applying the reasonable margins established company policy.
The economic appraisal process does not end here
In subsequent meetings with the responsible installation supervision establishing the criteria necessary to carry out the assembly of the structure. These criteria, complex projects are set using the 3D model itself, on which an assembly sequence planning (4D). With the clear interpretation of the structure showing in 3D has a clear vision of assembly time and auxiliary equipment.
Within 2 weeks we are ready to bid fitted with a high added value:
- interactive 3D model that supports the presentation of the economic study.
- Detailed proposals for the assembly of different elements of the structure
- graphical display of assembly sequences.
- identification of inconsistencies and errors in the design drawings, whereas in stage work may lead to conflict, lost productivity, etc.
- proposals for resolving such conflicts.
Ultimately, the BIM methodology also allows us to improve the process of economic valuation. Logically
current software still needs a major route the process of obtaining actual costs from the 3D model. I'm thinking full models incorporating all elements of civil works and installations, as well as execution times determined from the magnitudes of the model.
In my opinion the current approach to BIM goes through the development in this field, we can comment further in a future article.
you soon.
