oq-gem

Glossary for gem taxonomy

Authors: Luke Allen, Andrew Charleson, Svetlana Brzev, and Charles Scawthorn

This online Glossary explains around 400 terms contained in the GEM Building Taxonomy v 2.0 and nearly 700 images.

The terms have been listed in alphabetical and numerical order. Text description of each term is accompanied by illustrations (photos and/or drawings) where possible.

We welcome contributions in the form of photographs or images, illustrating glossary terms. If you have any questions you can also contact us at buildingtaxonomy@globalquakemodel.org


The Direction attribute is intended to identify two principal horizontal directions of the building plan. It is possible to specify different Lateral Load-Resisting System (LLRS) and the corresponding Material of the Lateral Load-Resisting System in two directions called Direction X and Direction Y; these systems are often referred to as Hybrid Systems or Mixed Systems. Where it is possible to specify directions, Direction X is parallel to street, and Direction Y is perpendicular (orthogonal) to street. In some cases, it is not possible to identify Direction X and Direction Y - thus the user can select Unspecified Direction.

Note that other types of hybrid systems can be described by the Hybrid Lateral Load-Resisting System attribute, which should be applied in one of the following cases: a) there is more than one LLRS in the building, but there is no clear distinction between LLRSs in directions X and Y, or b) there is only one LLRS, but two or more materials of the LLRS are used in different portions of the building.

Direction_1

A building showing possible orientation for Directions X and Y

EXAMPLE 1: A building has two different LLRSs: reinforced concrete flat plate (slab and column system) parallel to street, and reinforced concrete wall system perpendicular to street, as shown below. In this case, Direction X (parallel to street) is associated with a flat plate system (LFLS) (see Section 2), and Direction Y (perpendicular to street) is associated with a wall system (LWAL) (see Section 1).

Direction_2

EXAMPLE 2: The Direction attribute can be used to describe a hybrid LLRS from Chile, with reinforced concrete frames in longitudinal direction (Direction X) and confined masonry in transverse direction (Direction Y). It is assumed that Direction X (parellel to street) is longitudinal direction because entrance to individual housing units is in that direction (M. O. Moroni Yadlin).

Direction_Chile_Moroni_1

Direction_Chile_Moroni_2

EXAMPLE 3: The Direction attribute can be used to describe a hybrid system from Chile, where confined masonry is used in one direction and reinforced concrete shear walls in other direction (Moroni, Gomez, and Astroza, Chile, World Housing Encyclopedia Report 8). The photo shows an earthquake-damaged building, and the drawing shows a typical building plan (not related to the building shown on the photo).

Direction_Chile_WHE8_1Direction_Chile_WHE8_2