Andrade, Felipe

Confined Masonry Buildings: the Chilean Experience

Abstract eng:
Confined masonry construction was introduced in Chile in the late 1930s. Confined masonry structures had a great performance during the 1939 Chillan earthquake, providing the first real test for this type of construction during large earthquakes. At that time, the Ordenanza General de Construcciones included some design requirements for low-rise confined masonry buildings up to 2 stories high. A more rational code based on the allowable stress method was published in 1997 and provided design requirements for buildings up to 4 stories high. The confined masonry structures built in Chile in the last 20 years have followed the prescriptions of this code. The great earthquakes that hit the central and north part of Chile in 1985, 1987, 1997, 2010, 2014 and 2015 have shown the excellent behaviour of these structures subjected to seismic loading, when their design fully satisfied the code requirements. Contrarily, the use of partially confined masonry walls, built with a tie-column at one end of the masonry panel and a vertical tensile bar at the other end, may lead to collapse or, in many cases, to significant damage. Key components of confined masonry buildings are the horizontal (tie-beam) and vertical (tie-column) reinforced concrete elements. These components are cast in place after the masonry wall panels are built. Typical values for shear strength of Chilean masonry are between 0.5 and 1.0 MPa and the average value of wall density index (ratio between the crosssectional areas of all walls in one direction and the total floor area of the building) is about 3.5%. Analytical models to simulate the seismic behaviour of confined masonry buildings have been calibrated with lowamplitude vibration data (i.e., ambient vibrations) and seismic records obtained at the Community Andalucía Building, the only confined masonry building instrumented with an accelerometer network in Chile.

Contributors:

Astroza, Maximiliano

Conference Title:

Proceedings of the 16th World Conference on Earthquake Engineering

Conference Title:

16th World Conference on Earthquake Engineering

Conference Venue:

Santiago (CL)

Conference Dates:

2017-01-09 / 2017-01-13

Rights:

Text je chráněný podle autorského zákona č. 121/2000 Sb.