Portal frame

Portal frame structures are designed to span between supports and rely on fixed joints with moment resisting capacity where vertical supports connect to horizontal beams or trusses. Portal frame structures can be constructed using a variety of materials and methods. These include steel, reinforced concrete and laminated timber such as glulam. The connections between the columns and the rafters are designed to be moment-resistant, i.e. they can carry bending forces. 'They were first developed in the 1960s, and have now become the most common form of enclosure for spans of 20 to 60 m' Portal frame structures are designed to span between supports and rely on fixed joints with moment resisting capacity where vertical supports connect to horizontal beams or trusses. Portal frame structures can be constructed using a variety of materials and methods. These include steel, reinforced concrete and laminated timber such as glulam. The connections between the columns and the rafters are designed to be moment-resistant, i.e. they can carry bending forces. 'They were first developed in the 1960s, and have now become the most common form of enclosure for spans of 20 to 60 m'