Virtual Earthquake Reconnaissance Team (VERT) Summary by Ezra Jampole and Sahar Derakhshan.
The World Housing Encyclopedia provides technical information on the types, engineering, behavior during earthquakes, and retrofit strategies for housing around the world. Numerous resources existed prior to the August 24, 2016 Norcia, Italy Earthquake regarding masonry-type structures in Central Italy, the location of the epicenter of the earthquake. The reports are as follows:
Single-family stone masonry houses
Historic centers of many towns in central Italy are largely comprised of single-family stone masonry houses. Limestone blocks are typically set in lime mortar. The roof structure is typically heavy tile supported by wooden joists. The original structures typically have flexible diaphragms, and there is often no complete load path from the roof to the foundation. Performance during earthquakes is largely dependent on the quality of construction. Retrofit options include R/C ring beams, anchoring new concrete slabs into existing walls, and re-grouting brickwork with cement-based mortar.
Single-family historic brick masonry house (Casa unifamiliare in centro storico, Centro Italia)
Single-family brick masonry houses are common in central Italy, but are vulnerable to earthquakes. Walls can be strengthened via shotcrete jackets with steel wire mesh.
Single-family stone masonry house
In urban regions of Italy, multifamily housing units are commonly constructed with reinforced concrete frames with masonry infill walls. The government of Italy has provided financial resources to upgrade them through new shear walls, columns, and strengthened foundations.
brick masonry farmhouse with a “dead door”
Single family farmhouse construction is common in the Padania Plain region of Italy. Residential and agricultural portions of these buildings are both typically two floors, however, the floor heights are no even, which can lead to damage during earthquakes because of the vertical irregularity.
Unreinforced stone wall rural housing
Unreinforced stone wall houses were constructed several hundred years ago and are common residences for wealthy families. This type of construction has several seismic deficiencies, including: poor bond between orthogonal walls, façades and walls and slabs, and roofs and walls. Tie rods and injection of new grout can strength and improve these connections.
Lower and middle class residential building in rural areas of central Italy
Single-family stone masonry buildings are common in Central Italy. Buildings frequently share perimeter walls with adjacent structures. Typical damage during earthquakes includes: detachment of slabs from walls, roof collapse, diagonal cracks in walls, and detachment at corners. Grout injection and tie rods can improve performance.
