Design Improvement of Composite Timber-Concrete Bridges Using Glued Laminated Timber

The development of the forestry sector involves the use of heavy vehicles, which exert a significant impact on the road surface comparable to the impact of temporary traffic loads АК and НК of class 14. This requires the construction of appropriate engineering structures to support forest roads. The wooden bridges previously used in road construction do not meet modern requirements for load-bearing capacity, durability, and safety. The most appropriate designs for forest roads are those that combine glued laminated beams with a cast-in-place concrete deck. Composite bridges, including timber-reinforced concrete bridges, have a 50-year service life, which proves the high protective properties of the reinforced concrete slab and the durability of the glued laminated beams throughout their life cycle. However, in our country, they are not widely used in road construction due to the preference for prefabricated reinforced concrete. Meanwhile, international experience demonstrates the effectiveness of using glued laminated timber in road construction. The development and implementation of timber-concrete bridge superstructures are ongoing in Russia as well as in other countries. This research focuses on the design of composite bridge superstructures based on the interaction between a cast-in-place concrete deck and glued laminated beams, considering the impact of A14 and H14 road loads. The load calculations for the elements of the considered structure have been performed. The results show that the structure's load-bearing capacity meets the requirements for logging bridges. The proposed bridge design can be used in both civil bridge construction and for forest roads, as a replacement for expensive and difficult-to-install reinforced concrete bridge superstructures.