The project involves the construction of a new cable-stayed bridge over the Daugava in Jēkabpils. In addition to the new Daugava crossing, the project will reconstruct the city's infrastructure at the bridge approaches on both banks of the Daugava. On the right bank of the Daugava, a large-scale roundabout is created, connecting the new Daugava bridge, Rīgas Street and the A6 state road, as well as providing the possibility to connect to the A12 state road in the future. On the left bank of the Daugava, the city infrastructure (streets, utilities, landscaping) adjacent to the Bebru district is to be reconstructed, creating separate flows for transit corridor (connection to the regional road P75) and local traffic (Bebru Street). The project includes environmental accessibility, landscaping and noise barrier solutions to reduce the impact of the new transit corridor on the urban environment.
A bridge with reinforced concrete pylons and a reinforced concrete stiffening beam is designed at the Daugava crossing. A reinforced concrete stiffening beam (as opposed to steel) is not a common solution for cable-stayed bridges, but the emphasis is on using as many locally available construction materials as possible. The bridge spans are 80m+260m+80m, carriageway width 8.50m and 2.25m wide sidewalks on each side. The aerodynamic performance of the bridge has been investigated with a wind tunnel test, in which a 1:75 scale model of the bridge was tested in the wind tunnel.
The project has gone through several stages of development up to the construction design stage, with JSC Ceļuprojekts acting as the contractor in all of the stages:
- 2005-2008 Research project "Feasibility study of the Latgale motorway section Pļaviņas-Jēkabpils (Jēkabpils bypass) and a new Daugava crossing", which considered 5 route options and selected a river crossing location.
- 2009 Mets "Route scheme for the bridge over the Daugava and road connections in the Bebru Street area in Jēkabpils", which included preliminary engineering studies, detailed examination of two bridge crossing route options, and consideration of several bridge design options.
- 2011-2013 Sketch design "Daugava Bridge in Jēkabpils", where the technical parameters of the project were specified and analysed in more detail, an environmental impact assessment was carried out, a master option of the Daugava crossing was approved - a bridge of the cable-stayed system with reinforced concrete stiffening beams and pylons with a span scheme of 80m+260m+80m.
"When we started the development of the construction project, we realised that we had a great responsibility, both because the new Daugava crossing is adjacent to a peaceful but populated area of Jēkabpils, and because work on the project started in 2005, when the company's "old-timer" specialists worked on its solutions, who, regardless of the stage of the project's development, carefully consider every detail that affects the project solutions," says project manager Mārtiņš Taurenis.
Verners Straupe, project manager and chief bridge engineer, admits: "The use of a reinforced concrete span structure for the cable-stayed bridge, the construction of which is to be carried out using the cantilever concretinge method in a sliding formwork system, with the cables being gradually assembled and tensioned, can be highlighted as is a first for a bridge of this typeinnovations in Latvia and in the wider region. This choice led to a lot of learning during the design process, looking for structurally rational and technically feasible solutions."
The geotechnical investigations for the construction project were carried out by the Geology Department of "Ceļuprojekts". The exploration investigation works were carried out in 2 phases - in September 2012 drilling was carried out in the Daugava River from a floating platform, while from September 2016 to June 2017 exploration investigation was carried out for the design of the bank abutments and approaches. The works included geotechnical drilling at 103 points from 1 to 38 m depth, dynamic probing at 12 points, static plate tests (PLT) at 5 points and groundwater monitoring boreholes at 3 points. The drilling rigs used for the drilling operations are URB-2.5A, URB-2A2 and Geomash MBU224.