Synopsis
There are still hundreds of high-rise large panel system (LPS) dwelling blocks in the UK. These generally contain flats, but in some cases the accommodation is in the form of maisonettes or another multi-level arrangement. Block owners have a continual responsibility for their safety, which requires periodic inspection and structural assessment. The UK requirements for this particular class of building stem from the 1968 collapse of the southeast corner of Ronan Point, a 22 storey LPS dwelling block.
LPS dwelling blocks are basically gravity structures, as are traditional masonry constructed buildings. Typically they comprise precast reinforced concrete floor and roof components spanning onto storey high structural precast (generally plain) concrete wall panels. Vertical loads are carried to the ground through the structural wall panels, which also provide stability against lateral loads.
Historically the guidance used for the structural assessment of LPS dwelling blocks for accidental loads has been the Ministry of Housing and Local Government (MHLG) Circulars 62/68 and 71/68, which were produced shortly after the Ronan Point incident. MHLG Circulars 62/68 and 71/68 together with various other related guidance from that era, were never withdrawn and notionally remain in force today. However, the guidance has been rendered out-dated by subsequent developments.
This paper provides an overview of updated technical evaluation criteria and the associated guidance for undertaking a structural assessment of an LPS dwelling block for accidental loads.