e-mosty December 2017 MSS and Formwork Travellers | Page 22

BOWSTRING MOVABLE SCAFFOLDING
SYSTEM WITH ORGANIC PRESTRESSING
SYSTEM (OPS)
Magdaléna Sobotková
Figure 1: MSS in Turkey
I.
1. Movable Scaffolding System (MSS) with OPS
1.1 Development of the MSS
The Bowstring Movable Scaffolding System with
Organic Prestressing System (OPS) was developed
between 2007 and 2009.
OPS, which was developed back in 1999, is a concept
inspired by the behaviour of an organic structure
found in nature: a muscle. It is an active control
prestressing system which allows for an “optimized”
prestressing, because permanent undesirable stresses
are avoided and prestressing time-dependent losses
are greatly reduced.
OPS permits the design of lighter and more slender
structures with the same structural materials and is
particularly efficient in situations with high “live
load/dead load” ratio.
A very simple methodology was first developed for
simply supported beams. An effective control system
was achieved, where the main objective of ensuring
no tensions (or even low compressions) could be
generated at predefined control cross sections.
Later, after numerical simulations, it was concluded
that the concept would be particularly useful for
application on large bridge construction equipment –
usually known as Movable Scaffolding Systems or
shortly MSS.
4/2017