Civil construction personnel new to a thermal power project and seeking to have a brief overall idea of the same may find this article handy. While few minor things could vary from plant to plant, broadly most element would be similar & may differ only in shapes & sizes. Following are some of the major components of such a plant:
The Turbo-Generator(TG) structure: This very important structure is aptly called so as it houses both the turbines as well as the generators in it. The structure usually consists of a thick raft which supports a good number of columns.These columns in turn supports a quite thick concrete deck slab. It is this robust slab that holds the turbines & the generators. The TG deck slab is probably the most complicated RCC structure in a thermal plant as it has plenty of embedments/inserts in it to facilitate efficient fixing of the Ts & Gs and these make the thick slab quite uneven unlike ordinary slabs. This in turn makes the re-bar schedule more cumbersome. One needs to pay special attention while executing it. The TG deck slab is isolated from the rest of the structure by means of what is known as Vibration Isolation System(VIS). VIS usually consists of small spring units meant for absorbing the shocks or vibrations generated by the Ts & Gs thus protecting the structure from damages. These are placed on adhessive pads on the grouted tops of the columns. These are usually erected by specialised personnel often provided by the supplier itself. Steel plates are placed on top these spring units and the TG deck slab is cast on top of these once VIS is fully installed.
The Power House (PH): This structure usually lies adjacent to the TG structure and in fact, though the TG structure is an unique one it may actually be regarded as a part of the PH itself. The PH consists of several rows of columns tied by plenty of beams. This column-beam structure may host several racks depending on design requirements. There are also auxilliary foundations for equipments like Boiler Feed Pumps etc. Other smaller structures e.g., the Lube oil pit, Lube oil cooling pit, CEP and Cooling water pits etc. are usually situated near the PH/TG structures and are closely connected to these. Continued in Part 2