TWO‑WAY BENDING OUT‑OF‑PLANE COLLAPSE OF A FULL‑SCALE URm BUILDING TESTED ON A SHAKE TABLE

Bulletin of Earthquake Engineering, 17

REFERENCE

Tomassetti U., Correia A.A., Candeias P.X., Graziotti F., Campos Costa A. (2019). Two‑way bending out‑of‑plane collapse of a full‑scale URM building tested on a shake table. In Bulletin of Earthquake Engineering 17, 2165–2198. DOI: 10.1007/s10518-018-0507-5

Scope and methodology

• The upper floor of an URM cavity-wall terraced housewith pitched timber roof was tested in as-built condition using a shake table.

• The cavity wall is formed of loadbearing inner leaf of calcium silicate bricks sustaining a reinforced concrete floor and an external leaf made of clay-bricks connected to the inner leaf by means of metallic ties.

• Results include damage evolution, hysteretic response, performance of roof structure, identification of global limit states and detailed observed failure mechanism

FINDINGS

• The structure exhibited a box-type global response up to hPGA 0.39g with a first structural damage observed at hPGA 0.22g

• The observed damage pattern on the longitudinal walls was typical of flexural-rocking behavior.

• Despite the large flexibility of the roof system, the partial collapse of the specimen (at hPGA 0.63g) was driven by the out-of-plane failure of the East wall.

• Rocking mechanism of the slender longitudinal piers combined with the vertical input motion led to an uplift of the RC slab causing a loss of restraint at the top of the East transverse wall.

• At test completion, he RC slab rested on the outer veneer wall with a significant residual displacement (beyond 50 mm).

• Furnitures did not show any damage until hPGA 0.39g and vPGA 0.18g. Significant damage occurred at hPGA 0.63g and vPGA 0.34g with overturning of bookshelf not anchored to the wall.