Vibration should be well distributed so that concrete reaches a state of plastic mass with uniform density and vibrators should be used for compaction only and not for moving concrete horizontally along forms.

In case of kalpakam nuclear power station located in Tamilnadu, India shielding is provided by a double containment system with an inner cylinder of 600mm thick prestressed concrete surrounded by an outer wall of rubble masonry 711mm thick and two walls are separated by an annular air space 1m wide and in general prestressed concrete reactor and containment vessels and cylinder in shape facilitating slip form method of construction and circumferential prestressing resulting in considerable economy coupled with speedy construction.

Rheodynamic concrete generally referred to as self compacting concrete (SCC) is able to flow under its own weight and completely fill formwork, even in presence of dense reinforcements without need for any vibration whilst maintaining homogeneity and resulting in concrete of high early strength and durability.

When mixed in a central mixing plant, mixing time should be not less than 50s nor more than 90s and when truck mixer is used as in case of ready mixed concrete, a minimum of seventy to a maximum of 100 revolutions of drum or blades at mixing speed are required for complete mixing.

The prestressing system of dome in madras power atomic reactor vessel comprises of how many brands three banded layers housed within dome thickness of 250mm and this structure is also notable for being most economical and cheapest in world by comparison with 27 similar containment vessels which were designed and built around world in 1967.

The cantilever roof is estimated to deflect by 280mm near tip under maximum wind effects and safe movements of sliding door is ensured by provision of a concrete channel section of adequate depth at tip of roof and hanger has been planned and designed to withstand dynamic effect of wind gusts of coastal zone during cyclonic wind reaching a speed of 160knmph and hanger can also be widened whenever required as side walls are independent of roof and airbus hanger was designed by STOP consulting engineers for Indian airlines corporation.

For medium and long spans prestressed concrete is ideally suited for super structure of bridges and structural forms generally used for bridges are listed as follows solid slabs(10-15m), voided or hollow slabs(15-25m), rigid frame bridges(15-30m), Tee beams and slabs(20-40m), two cell box girders(30-70m), multi cell box girders(40-80), balanced cantilever type bridges(20-30m), continuous girders of variable depth(30-40), cable stayed bridges(100-500m).

Architectural capabilities constitutes essence of conceptual and aestic aspects of structures and domain of construction activity involves several known and unknown features such as management of materials and labour, mobilization of suitable cost effective techniques, treacherous foundations problems adverse water conditions, planning and scheduling of construction process to a time based frame, constant interaction with design engineer, architect, site engineer, construction workers and ability to take sound and daring decisions at times of crisis.

Pneumatic caisson foundations consisting of steel cutting base and concrete pier are adopted for deep foundations in watery situation and reader may refer to monograph design of bridges by author for detailed descriptions and structural design of piles, wells and caissons.

Prestressed concrete aircraft hangers normally require large column free spaces and introduction of prestressed concrete in India in year 1939 resulting in larger spans of column free structures suitable for aircraft hangers such as that planned for Karachi airport in 1942.