On site and laboratory investigation to assess material and structural damage on some churches hit by an earthquake

At the end of 2004, an earthquake (5.2 Richter scale) hit the eastern part of the Lombardy Region in Northern Italy. No casualties occurred luckily, but many buildings were damaged and particularly affected was the vast patrimony of Churches. The authors were asked by various parishes to carry out a preliminary after earthquake investigation on 10 Churches and 2 rectories, carefully chosen to be representative of the total number existing. The aim was to assess the state of damage of the structures and the properties of the materials as a base for the preservation and repair projects. The investigation was carried out following the same procedure for all the Churches: archive documentary research, geometrical and crack pattern survey and interpretation, definition of the possible incipient collapse mechanisms, mechanical characterization of the masonry through flat-jack tests, use of sonic tests to define the density of the walls, individuation of the masonry section typology by sampling, ultrasonic tests on stone columns, vibration tests on tie rods, definition of mortar and stone properties sampled from the walls through chemical, physical and mechanical laboratory tests