Project name: Tuzla – Orašje Highway, subsection LOT 5
Location: Bosnia and Herzegovina
Investor: JP Autoceste FBiH
Contract value: 1.292.571,20 EUR
Design team: IPSA Institut – Transport Infrastructure Department. The team consists of highly skilled road and infrastructure engineers who have been delivering strategic transport projects in Bosnia and Herzegovina for decades.
The goal: To design a highway section that connects Tuzla to the Croatian border at Orašje, creating a direct link to the European Union. This connection significantly improves regional connectivity, enhances economic opportunities, and supports sustainable infrastructure development in the Tuzla Canton, the most populous and economically active region in Bosnia and Herzegovina.
Design objects: The project covers a 23.2 km highway section (LOT 3,4,5) with complex geomorphological conditions. LOT 5 subsection has length of 7.5km. The scope includes alignment design, optimization of route variants, detailed solutions for landslide mitigation, regulation of watercourses, embankment construction, and integration of all necessary infrastructure elements.
Software solution used: Plateia by CGS Labs
Project goals
The Tuzla–Orašje highway project is of strategic importance for improving the transport connectivity of Bosnia and Herzegovina. Tuzla Canton, as the most populated and economically developed canton in the country, will gain a direct connection to the Republic of Croatia and the European Union through this highway.
The main project goals were:
- Identifying the optimal alignment considering challenging terrain and multiple constraints
- Developing the conceptual and main design documentation
- Obtaining urban planning and construction permits, as well as environmental approvals
- Aligning all design documentation with the investor’s requirements
Image: Overview map of Tuzla–Orašje Highway showing LOT 5 alignment and project location.
Challenges and solutions
1. Difficult terrain and landslides
The Tuzla–Maoča section (LOT 5), with a length of 7.5 km, presented the most challenges of all the lots on this section of the highway. The biggest difficulty was avoiding landslides, for which this part of Bosnia and Herzegovina is well known.
To address these risks, the design team sometimes compromised on alignment geometry, including reducing the design speed in certain segments, allowing the route to bypass most landslide-prone areas and thereby significantly reduce the number of retaining structures needed.
An economic analysis was conducted to compare costs: building retaining structures to stabilize the terrain versus expropriating nearby buildings. The results showed that in many cases it was more cost-effective to move the alignment closer to the properties and proceed with expropriation rather than invest in extensive retaining structures.
“When you avoid landslides, you approach houses. We performed an economic analysis – what is more expensive: building a retaining structure to stop the landslide or expropriating the properties? The analysis showed that expropriation was often the better solution.”
– Amar Čorbo, Road and Highway designer at IPSA Institute
Plateia software also played a key role in refining the alignment. The comparative axis feature, allowing offset alignments, enabled the team to test different axis separations and find the optimal configuration.
2. Mining tunnels and ground subsidence
A large portion of LOT 5 runs over abandoned mining tunnels, where the risk of subsidence is high. Initial designs included bridges, but due to uncertainty over ground stability, these were replaced with embankments as a more reliable and cost-effective long-term solution.
In some sections, existing structures along the alignment forced the team to decide whether to cut deeper—risking landslides—or shift the route over properties requiring expropriation.
“In several places, we faced the choice: go into a deeper cut, possibly into a landslide, or over houses requiring expropriation. With Plateia, we modeled two or three variants, compared cross-sections, and analyzed economic and social impacts. The software gave us a clear basis for the decision.”
– Predrag Šarkinović, Head of department for transport infrastructure design
3. Watercourse regulation
Another major challenge was coordinating the alignment with existing watercourses in areas constrained by landslide-prone slopes and the main road. In one critical section, the highway had to be placed between the main road and a stream, with a landslide on the opposite side. To avoid the sliding area, the alignment was shifted as close as possible to the main road, leaving minimal space for stream regulation.
The stream was regulated using an initial culvert, but a gabion wall located nearby created a potential conflict. Using Plateia’s 3D modeling capabilities, both the wall and regulation were modeled, cross-sections were generated, and conflicts were resolved within the software.
Colleagues from the Hydro Bureau used Aquaterra, fully compatible with Plateia, to design the regulated riverbed. The integration of both software solutions allowed the team to import and visualize all hydraulic works in the highway layout, minimizing execution risks.
Image: Project-specific cross-section of highway embankment – LOT 5, Tuzla–Orašje Highway.
Role of software
Plateia by CGS Labs played a crucial role in all stages of design:
- Rapid adjustment of alignment variants to meet investor requirements
- Variant analysis based on technical feasibility and cost efficiency
- Visualization of terrain adaptations and detection of potential collisions (e.g., with watercourse regulation, retaining walls, road infrastructure)
- Preparation of detailed cross-sections and vertical geometry
Below you can watch the project video prepared by Predrag Šarkinović, Head of the Department for Transport Infrastructure Design.
Conclusion
LOT 5 of the Tuzla–Orašje Highway demonstrates how a combination of advanced engineering expertise and innovative design tools can overcome the most challenging geotechnical and spatial constraints. Through careful route optimization, risk-based decision-making, and seamless integration of Plateia and Aquaterra software, the IPSA Institut team delivered a design that is both technically robust and economically efficient.
This project not only enhances the transport connectivity of Tuzla Canton but also establishes a key link between Bosnia and Herzegovina and the European Union. By successfully managing landslides, abandoned mining tunnels, and watercourse regulation, the project stands as a strong reference for complex infrastructure works in demanding environments.
About the Company
IPSA INSTITUT d.o.o. Sarajevo is a leading independent consulting firm in Bosnia and Herzegovina. Founded in 1958, IPSA has delivered more than 8.000 projects across the region, building a strong reputation and brand. IPSA specializes in developing infrastructure systems with a wide range of services, such as: spatial planning, master planning, feasibility studies and design, tender preparation and project management, environmental impact assessment and waste management, construction supervision, technical assistance and optimization.
They provide high-quality consulting engineering services for various sectors, including transportation, water and power supply, building construction, and environmental protection. IPSA has partnered with over 70 consulting firms from the European Union, the USA, and Japan. IPSA is a company that has 90 engineers and 80% of them are from various profiles. IPSA’s teams consist of university professors from the Faculty of Traffic and Communication, the Faculty of Civil Engineering, the Faculty of Architecture, and the Faculty of Electrical Engineering.