Click here to read the final report of the CLAY BLOCK MASONRY project.

A concise overiew of the project is available in the Joint brochure of the SERIES TA facilities.

TITLE OF PROPOSAL: Full scale testing of modern unreinforced thermal insulation clay block masonry houses

HOST TA FACILITY: LNEC, Lisbon, Portugal

TA AGREEMENT BETWEEN USERS AND FACILITY: 7 Jan. 2010

STARTING DATE: July 2010

END DATE: July 2013

NO. OF USERS (researchers): 11

LEAD USER:
Suikai Lu - Wienerberger AG (Austria)

ADDITIONAL USERS:
Hervé Degee - University of Liège (Belgium)
Christophe Mordant - University of Liège (Belgium)
Veronika Sendova - Institute of Earthquake Engineering and Engineering Seismology-IZIIS (fYR Macedonia)
Zoran Rakicevic - Institute of Earthquake Engineering and Engineering Seismology-IZIIS (fYR Macedonia)
Ema Coelho – LNEC (Portugal)
Alfredo Campos Costa – LNEC (Portugal)
Paulo Candeias – LNEC (Portugal)
Luís Mendes – LNEC (Portugal)
António Correia – LNEC (Portugal)
Andreas Jäger - Wienerberger AG (Austria)

SUMMARY OF PROPOSED RESEARCH:

Model A and model B in the LNEC test lab

This project focuses on testing of the seismic performance of modern unreinforced high thermal insulating clay block masonry houses. This solution represents a very common construction method in Europe that still lacks seismic vulnerability assessment. The aim of this project is to validate experimentally the effective three-dimensional dynamic response under seismic events.

Experimental setup

Two full scale 2-storey models with dimensions of 3.7x4.2m² in the ground floor and a height of 5.4m were built on specially designed steel foundations. Model A is regular in plan while model B includes significant irregularities. Four additional masses of 600kg  each were placed on the first floor for considering a life load of 2 kN/m².

For building the models premium insulation filled clay blocks from Wienerberger with excellent mechanical and thermal performance were used. The blocks were masoned with thin layer mortar with a thickness of approximately 1mm.

The instrumentation setup was conceived in such a way to collect as much relevant data as possible to characterize the overall and local seismic behaviour of the tested mock-ups.
 

Testing procedure and results

As seismic input a semi-artificial earthquake based on a central European record (Friuli 1976 – Tolmezzo Station) fitted to a specific EC8 elastic response spectrum was used. From this reference signal (REF), with a PGA of 0.36g (N-S) and 0.32g (E-W), other signals with scaled intensities were generated (12.5% REF, 25% REF,…). The models were loaded in eight stages with consecutive uniaxial loading in both directions for the first stage, followed by determination of natural frequency, followed by biaxial loading for the next stage, and so on. For each load level several shakes with increasing intensity were performed to reach the final intensity of the single step, giving a total number of 62 shakes for model A and 54 shakes for model B.

The tests on both models were stopped at the REF intensity level because heavy damage was observed and  collapse was imminent. With this result the design PGA predicted by pushover analysis was exceeded by a factor of 2.0 to 2.5. In a next step the data collected during the tests will be analyzed in detail and additional numerical simulations will be performed to further assess the seismic performance of the tested type of masonry.