STRUCTURAL ANALYSIS AND DESIGN OF TIMBER REINFORCED STRUCTURES USING EURO CODE: A CASE STUDY OF MULTI CELL CULVERTS
Abstract
This study looks at the design, structural performance, and cost of building a triple-cell box culvert reinforced with sustainable timber instead of traditional steel. Using Eurocode standards for timber-concrete composite (TCC) systems, we tested how the structure's top slab, bottom slab, and side walls handle weight and pressure. The structural analysis calculated design loads of 77.78 kN/m for the top slab, 17.06 kN/m for the side walls, and 105.74 kN/m for the bottom slab. These forces caused bending pressures (span moments) of 100.16 kNm, 25.38 kNm, and 175.73 kNm, and peak support moments of 65.15 kNm, 39.84 kNm, and 113.54 kNm, respectively. The highest tearing forces (shear forces) reached 156.13 kN on the top slab, 24.90 kN on the side walls, and 233.44 kN on the bottom slab. To handle these loads safely, we used a uniform reinforcing grid of C24-grade timber sections measuring 100 × 50 mm, spaced at 300 mm center-to-center. To make sure the timber and concrete bond together perfectly, mechanical shear connectors were added along the joints. We used 26 connectors per meter for the top slab, 4 for the side walls, and 38 for the bottom slab. For a fair comparison, we also designed a traditional steel-reinforced culvert using Eurocode 2 standards. This baseline setup required heavy steel bars (Y20 @ 200 mm with Y12 @ 150 mm distribution bars) on both faces of every concrete member. The final financial analysis revealed that the timber-reinforced alternative costs ?1,543,800, while the standard steel concrete structure costs ?3,382,000. This represents a massive 54.4% cost reduction without sacrificing any structural safety or performance margins. Ultimately, the findings confirm that Eurocode-compliant timber reinforcement is a reliable, practical, and highly economical alternative to traditional steel rebar for multi-cell culvert projects.
Keywords: Euro code (EN),Timber concrete composite (TCC) , Timber design, concrete design, engineering code of practice, Culverts, Triple cell culverts
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