For reasons of  economic efficiency and  to reduce noise emissions, the deck  slab and the cycle path slab were designed as reinforced concrete slabs, supported by steel cross girders at distance between 3.33m and 3.57m. By choosing effective prefabricated slabs with cast in-situ supplement, laborious form-works were not necessary. In the architect's design, V-shaped piles were planned onto which the superstructure is placed transversally rigid The  load-bearing  structure  is founded  on driven piles made  of prestressed concrete, which are common  in the Netherlands, with cross section dimensions of  bid - 450/450 tnm.. Figure 7:  The foot and cycle path For  structural and dynamic  calculations of  the  superstructure,  the  steel structure was represented as spatial bending-stiffbar system and the composite reinforced concrete slab by finite elements was included into this model. The  truss  nodes,  arch base points  as well  as bearing points and transverse bulkheads were described by  finite element method and  integrated  into  the bar system for dimensioning. In this way complicatc:d considerations of  bearing conditions of  separate  systems became unnecessary. Moreover, effects of  stiffnesses of  the large truss nodes on calculations and  the deformation behaviour of  the bar system. could be determined. Also represented in the  system. were  the piles to  incorporate the  :infl.uence  of  the pile foundations.
It  should be emphasized that the selected continuous system :fulfils durability require-ments of  the  load-bearing structure as well as  the  track:  superstructure. The client wilt not have to support high maintenance costs caused by a ballast bed prone to wear and deforma-tions. 5.  Systems Engineering The client prescribed  systems  engineering  for design  of  the load-bearing  structure, which means in  general a method  to design and control complex development and design processes in SlWh a way  that project requirements result in  an optimised ovcra1l design. Not only the final product should be discernible but also alternative solutions, decisions and thcir hnpacts. The  structure of  the design process, called the  system breakdown  st:nK:turc:  (SBS),  is described in  a series of  documents based on  the client's specifications and the requirements from construction  rules and regulations. Variant studies, compared  to each other  in  a so-called  trade-off matrix, provide infonna-tion about functional, qualitative and financial risk assessment as well schedule-related risks of  different design concepts. A  trade-off matrix and verification plans guarantee that all  requirements are met. Other components  of the  SBS  are RAMS  analysis  and  safety  analysis  that  descnoe and document in which form and by which precautionary measures the design can :fuIfi1 the required conditions. The global system design and all detailed designs derived from  the  system design are subjected to this process. Through constant and close dialogue and discussions with the cli-ent of  all design approaches this procedure ensures the desired optimum design success and reduces  through documented self-<:ODtrol  the  extent of  testing by the  client to  spot check controls. Systems engineering had also been stipulated for construction execution to make sure that the requirements included in  the final design as well as the additional requirements for construction site operation were: taken into account The structure of  the design process, called work breakdown structure (WBS), comprises more compreheosive subjects for example the execution of  construction site investigations, environmental measures, protection of  third party objects such as cables and conducts, ap-provals, tests and surveying are just some of  the necessary measures to be taken. Another part of systems  engineering  is risk management which can encompass  toler-ances of  the  load-bearing structure or schedule-related risks such as public permissions that are obtained with delay. The result of  this work process is a load-bearing structure that meets present and future functional and economic requirements. 铁路桥英文文献和中文翻译(3):http://www.youerw.com/fanyi/lunwen_32979.html