Control in Precast Operations: Importance of Inter Departmental Co-ordination
Kapilesh Bhate, Planning and Control, Precast Infrastructures Pvt. Ltd., India
Our industry is generally termed only as "Pre-Cast" Industry. The essence of this paper is to give importance to the additional "Pre" to Precast – "Pre-Engineered Pre-Cast".
Pre-Casting is simple. Pre-Engineering is not only challenging, but also missing in many cases. In such cases, the simplicity of Pre-Casting is not leveraged and leads to a lot of "Pre-Cast Post-Engineering" Co-ordination between Deptts. and in some cases, even Organisations.
Pre-engineering means, frozen architectural Drawings, design, element IDs, element geometry, reinforcement and strand details, concrete specifications, connection details, MEP Details incorporated with the layouts of each floor, and thereafter, referencing their effects in Production Dwgs.
The last step in Pre-Engineering thus, remains scheduling the elements to their respective moulds, stockyard, trailers and installation by assigning particular dates for each stage.
IntroductionThis paper is not prepared based on any large sample space and research conducted in Precasting Companies of the world, but is prepared from basic first principles, presuming an ideal process and studying probable deviations from it.
In Pre-Engineering, we already ‘construct' the elements of the building once, before-hand, albeit on paper and only then, proceed to Precasting the elements physically.
Thus, Pre-Casting is nothing but, constructing physically, in concrete, the already constructed building on paper.
There can be two cases in which a Project can be dealt with:
MetaCase 1: Pre-Engineering -> Pre-casting
MetaCase 2: Pre-casting -> Post-Engineering
The moment, this Meta-sequence is changed from MetaCase 1 to 2, then the issues start arising one after the other, as everything is anyways ‘connected' to each other. Nothing goes un-detected in Precast Projects as the ultimate fitment test always happens on site.
Once Pre-Engineering is frozen, (as in advanced countries like Japan, to name just one) then starts the actual process of Operations. It starts right from establishing one TBM on site to the dry/wet connection of the last element of the last floor of the last Installation Part and everything in between. Missing the Actual Footing center by 50mm – means dealing with the issue till the last level, as everything is already Pre-Casted as per the Pre-Engineered Dwgs (assuming the Product is also actually as per the Production Dwg)
Terminology and common baselines of language and reference are also very important for all the Operations to function smoothly. This needs to be set in the Pre-Engineering Stage – Nomenclature and Identification of Precast Elements, Installation Parts. So is the identification of the Project Team, establishment of Communication Protocol. This paper will in brief, study the roles and interactions of the above mentioned Depts with each other. In case any of the above activities are not done in-house, then, briefly, we will touch the organisations involved such as Architect, PMC, Client's Structural Consultant, Subcontractor for Installation, Transportation, etc.
This paper is written from point of view of the Precaster.