Innovative composite overpasses on the Romanian A1 motorway - Economical Bridge Solutions based on Innovative Composite Dowels and Integrated Abutments - page 142

Figure 3: a) Left: longitudinal section, b) Right: design model

Figure 4: General cross section [2]

The infrastructure is composed of four drilled piles for every axis - each being 10 m
long, continuing a foundation slab - 2,0 m wide and 1,20 m high - and one reinforced con-
crete straight wall of 1,50 m depth and approximately 10,0 m height (“Fig. 3”). Whilst the
infrastructures are made, close to the final bridge position, four prefabricated steel girders are
brought from the steel plant and are fixed on temporary concrete supports, designed to take
into account the precambering of the girder. On those temporary platforms the upper rein-
forced concrete flange of the precast composite girders begins to take shape with its variable
thickness 10 cm ÷ 15 cm (“Fig. 5”, “Fig. 6”). The concrete flange serves as a pressure zone,
horizontal bracing during erection and formwork for the in-situ slab.
Then, the finished precast composite beams - the VFT ® girders are aligned on the in-
frastructure in the final position. During the design stages and also during execution, special
attention was paid to the reinforcement in the frame corners (“Fig. 7”). In accordance with
the designed technology, the pouring of the superstructure plate was made in two steps: first
on the frame corners areas and only afterwards the works were continued in the middle part
of the superstructure. The superstructure plate is 20 cm ÷ 30 cm thick.
The last remaining work was the proper equipment of the structure: the waterproofing
system, the pedestrian parapets, the guardrail protection, the translation slabs, earth filling
with the corresponding degree of compaction and adequate materials, road structure (“Fig. 8).