Earthquake Resistant Design Of Buildings Research Articles

The development of seismic zones and the evaluation of lateral loadings for earthquake resistant design of buildings in Papua New Guinea

A recently published seismic zoning map of Papua New Guinea does not correlate particularly well with either presentday seismicity or tectonic models of the region. Several reasons are given and a modified version of the map is presented for discussion and as a replacement in the Building Code.

The development of seismic zones and the evaluation of lateral loadings for earthquake resistant design of buildings in Papua New Guinea

The basis for modern earthquake resistant design can be considered to be a two stage process the objectives of which can be summarised as follows:
 
 Provide the structure with sufficient strength and stiffness to resist moderate earthquakes so that the frequency of occurrence of structural and non-structural damage is acceptably low, and
 Ensure that the probability of collapse of the structure and the risk to life in a severe earthquake is acceptably low.
 
 The first stage can be satisfied by seismic zoning to ensure that the risk of damage to structures of similar structural type is acceptable and approximately uniform over the whole country and by restricting interstorey deflections under moderate earthquakes.
 The second stage can be satisfied by the use of structural type factors.
 In particular, this study explains how these principles were used to develop seismic zones and evaluate lateral loadings for Earthquake Resistant Design for Buildings in Papua New Guinea.

Dynamic aspects of the code for the design of earthquake resistant buildings

A brief review is given of the most important aspects of the dynamic behaviour of buildings, during elastic and inelastic deformations under earthquake loads, which must be considered for the effective utilization of the NZS 4203 "Code of Practice for General Structural Design and Design Loadings".

Shear and Overturning Moment for Earthquake-resistant Building Design

The provisions of the present Canadian and U.S. seismic codes are examined with respect to their requirements on the distribution of seismic forces and overturning moments throughout the heights of building structures. Assuming the code design base shears to be correct, it is shown that the prescribed distribution of lateral forces may underestimate the shear forces in the upper stories of the building. It is further shown that the contribution of the higher modes is not directly related to the height-to-width ratio of the building, but rather to its fundamental period of vibration. By idealizing the building as an average uniform cantilever deflecting partly in a shear mode and partly in a bending mode and by taking a root-sum-square combination of the modal responses to a standard seismic acceleration spectrum, the envelope of the resultant maximum shears throughout the building height is obtained; the maximum overturning moments throughout the building height are obtained in a similar manner. By comparing these with the cantilever overturning moments computed from the shear envelope referred to above, the moment reduction factors applicable to the various levels of a building are calculated. New empirical relationships are then developed to approximate the shape of the maximum shear and overturning moment envelopes.

Design lessons from recent destructive earthquakes

Recent severe earthquakes have selectively damaged or destroyed many large modern buildings. The destructive earthquake s at Caracas in Venezuela, July 1967, near Tokachi-oki in northern Japan, May 1968, and the two earthquakes at Manila in the Philippines, August 1968 and April 1970, have all highlighted important factors which should be considered during the earthquake-resistant design of buildings. Reports on these earthquakes which directly supplement this paper are listed in the references.