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ABSTRACT This paper presents an analysis of the possible application of integrated heating-cooling systems in buildings. The general algorithm of integrated heating-cooling system design aid was formulated. The evaluation criteria [...]

Abstract: The need for effective evacuation of any building is of great importance in cases of emergency and risk. In this paper, a mathematical approach is developed and presented for [...]

A new pushover analysis procedure derived through adaptive modal combinations (AMC) is proposed for evaluating the seismic performance of building structures. The methodology offers a direct multimode technique to estimate seismic demands and attempts to integrate concepts built into the capacity spectrum method recommended in ATC-40 (1996), the adaptive method originally proposed by Gupta and Kunnath (2000) and the modal pushover analysis advocated by Chopra and Goel (2002). The AMC procedure accounts for higher mode effects by combining the response of individual modal pushover analyses and incorporates the effects of varying dynamic characteristics during the inelastic response via its adaptive feature. The applied lateral forces used in the progressive pushover analysis are based on instantaneous inertia force distributions across the height of the building for each mode. A novel feature of the procedure is that the target displacement is estimated and updated dynamically during the analysis by incorporating energy-based modal capacity curves in conjunction with constant-ductility capacity spectra. Hence it eliminates the need to approximate the target displacement prior to commencing the pushover analysis. The methodology is applied to two existing steel moment-frame buildings and it is demonstrated that the AMC procedure can reasonably estimate critical demand parameters such as roof displacement and interstory drift for both far-fault and near-fault records, and consequently provides a reliable tool for performance assessment of building structures. CE Database subject headings: Nonlinear analysis; Seismic effects: Drift: Earthquake engineering: Model analysis.

In this paper the resulting equation for natural vibration of buildings with coupled shear walls is proved to be the forth-order Sturm-Liouville differential equation, and a hand method for determining the first two periods of natural vibration of the buildings is presented. The method is accurate and simple, compared with other calculating methods. Once the structural parameters [alpha]H and [micro] of coupled shear wall building are computed, the periods of the buildings can be readily obtained. The value of the method is that it will allow a more consistent and accurate use of code formulas for calculating the earthquake induced maximum base shear in a building. Use of the method is economical with respect to both computer time and equipment, e.g., a hand calculator would suffice to handle the calculations of periods of the buildings. This paper is thought to be useful for the practicing engineer. CE Database subject headings: Shear walls; Coupled walls; Vibration; Buildings.

The hygrothermal behaviour of the building envelope affects the overall performance of a building. Numerous tools exist for the simulation of the heat and moisture transfer in the building envelope and whole building simulation tools for energy calculations. However, working combinations of both models for practical application are just about to be developed. In this paper such a combined model, that takes into account moisture sources and sinks inside a room, input from the envelope due to capillary action, diffusion and vapour absorption and desorption as a response to the exterior and interior climate conditions as well as the well-known thermal parameters will be described. The new model is validated by performing a series of field experiments and the moisture buffering capacity of the building envelope is investigated. In the conclusions the possible range of future applications of hygrothermal building performance models is addressed and the needs for further research are identified. Keywords: Hygrothermal simulations; Indoor humidity; Moisture buffering; Intermittent air-conditioning; Humidity control

The main purpose of this paper is to investigate the difference between the rigid-floor and flexible-floor analyses of buildings. The finite-element method is used to analyze the buildings with and without shear walls. From a number of response-spectrum analyses, the rigid-floor model was found to be accurate enough for regular and nonregular buildings without shear walls. However, the difference between the rigid-floor and flexible-floor analyses can be large for the buildings with shear walls. Thus, an error formula is generated using the regression analysis of the rigid-floor and flexible-floor analyses from 520 rectangular, U-shaped, and T-shaped buildings. Using this formula, one can estimate the error of the structural analysis of a building with shear walls when the rigid-floor assumption is used.

Kobe, Japan--Scientists who have studied the Kobe earthquake have come to an unsettling conclusion: Dozens of cities around the world are ripe for a similar catastrophe. Seismological and engineering studies [...]

What Is Worse Than 'The Big One'? THE first thought in the minds of many residents of the city of Whittier when the first shock hit them was 'Is this [...]