Knauf Seismic Design

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Earthquakes can cause huge economic losses. Primarily, however, they also cause personal distress with deaths, injuries, the loss of living space, and the devastation of living conditions. Knauf Seismic Design Earthquake Safety with Knauf Systems Most of these losses are set off by buildings that are unable to resist earthquake loads. In order to avoid, or at least reduce these damages there are three basic principles related to both cost-effective construction as well as the earthquake safety of buildings [1]: Figure 1: Earthquake-damaged building 1.) In the event of slightly severe earthquakes, buildings must be able to survive without damage. 2.) In the event of moderately severe earthquakes, the damage to the buildings must be negligible. 3.) In the event of severe earthquakes, the buildings must be prevented from collapsing. Above all, the protection of human life must be assured by ensuring the options of survival, escape and rescue in the event of earthquakes of any severity. Figure 2: “Soft story effect” The appropriate literature [2], [3] and National Standards (DIN 4149, Eurocode 8 - ENV 1998-1 etc.; see pg. 19) provide constructional guidelines for the technical implementation of these basic principles. Going by these mentioned technical guidelines, Knauf Systems present several clear advantages as compared with solid concrete and masonry constructions. 2 Figure 3: Collapsed “soft story”
Soft Buildings Advantages: Appropriate for rigid subsoil (higher frequency) due to low natural frequency. Required ductility is easier to achieve. An easier calculation procedure. Disadvantages: Non-load bearing elements have to be isolated (movements and deformations, load distributions). High stress in junctions due to larger movements. Rigid Buildings Advantages: Appropriate for soft subsoil due to high natural frequency. The junctions are less elaborate due to smaller movements. Joints with non-load bearing construction components with fewer problems. Disadvantages: Higher stress when subsoil is rigid. Lower ductility. The calculation procedure is more complex. a) floor plan vertical layout Structural Basics 1.) Rigidity of load-bearing structure. A decision in favor of or against soft or rigid structures has to take the conditions of the foundation soil into consideration. Rigid structures should be founded on soft subsoil, and soft structures should be founded on rigid subsoil in order to avoid undesired large stresses caused by the effects of resonance. 2.) Ensure a steady and symmetrical distribution of weight and rigidity in the vertical and horizontal layout taking non-load bearing construction components into consideration, in order to avoid higher torsion-related stress (fi gure 4). 3.) Avoid “top heaviness” of the vertical layout related to both weight (including nonload bearing components) and rigidity. In a majority of cases, the “soft story effect” is responsible for the collapse of buildings in the event of an earthquake (fi gures 2 and 3). b) floor plan vertical layout Figure 4: a)Unfavourable layouts b) Improvement through structural subdivision 4.) Use ductile materials for non-load bearing construction components. Avoid brittle materials that display unfavorable behavioral patterns in the case of a collapse (unannounced collapses, brittle fraction). They could thus lead to undesired load distribution when not installed properly, with higher destruction effects when compared with more ductile materials (fi gure 5). The objective should be to implement these basic rules in the construction of new buildings as well as in the improvement of Figure 5: Damage caused by collapsing masonry existing buildings. 3
Page 1: Knauf Seismic Design Edition 08/200
Page 5 and 6: Knauf Seismic Design Seismic Zones
Page 7 and 8: Knauf Seismic Design Less Weight -
Page 9 and 10: Knauf Seismic Design Applications N
Page 11 and 12: Table 6: Maximum Resistible Horizon
Page 13 and 14: Table 8: Knauf Suspenders 0.25 kN A
Page 15 and 16: Table 10: Collapse loads for metal
Page 17 and 18: Knauf Seismic Design Material Value
Page 19 and 20: Table 14: Selected international st

Knauf Seismic Design

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