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From early 1990s several timber road bridges have been built in Norway. After having gathered experience, increasingly larger bridges have been developed with longest span so far of about 70 metres. Common for these long span bridges has been a truss system as main load-bearing system. A typical connection in timber trusses consists of embedded steel plates in sawn slots and dowels through holes in the plates which give high load-carrying capacity. It is difficult to take high bending moment in timber connections, so steel members are often used where it is necessary to transfer moments, e.g rigid frames for lateral stability. As bridge deck is often used a stress-laminated deck plate consists of glued-laminated or common plank clamped together on their wide face by pre-stressed high strength steel rods. To meet the requirement of 100 years service life, the timber has been impregnated using chemicals, with salts and/or creosote.





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