Journal of Architectural Engineering

This paper presents new aspects of Anton Tedesko’s design for an important thin shell concrete roof. The study of this roof results from the examination of original engineering drawings and calculations which we present with the goal of promoting a greater understanding of the structural design of a major figure in the tradition of 20th century building.

Atria are commonly constructed in building complexes of the Far East, including Hong Kong. Fire safety has become a concern as a consequence of several large fires that have occurred since 1996. Atria are usually designed with an appropriate means of escape, but temporary structures or partitions are sometimes placed on the atrium floor. As a result, the evacuation patterns of occupants are then altered significantly from the original design. Safety aspects of evacuating occupants from the atrium floor were studied by considering two atria in Hong Kong under different uses. Simulations of each atrium were carried out to study the evacuation time with a different number of occupants. The first atrium was used to demonstrate how evacuation time would be prolonged by putting in temporary structures, and, the second was used to illustrate how locations of exits should be designed carefully. The software BuildingEXODUS was selected as the simulator. Results illustrated that emergency exits have to be provided carefully, not just by increasing their number. Safety management should be worked out by controlling the number of people staying in the atrium. A good choice is to apply engineering performance-based design. As most of the evacuation software was developed in the Western world, empirical parameters such as preaction time might not be suitable for the Far East. For giving better safety, studies on emergency evacuation are proposed.

This paper presents results from the simulation of localized, short-duration bioaerosol releases in a hypothetical building similar to a dormitory or barracks using public domain multizone air flow and contaminant dispersion modeling software. The primary purpose of the modeling was to generate example exposure data to be used in the development of a comprehensive microbial risk assessment methodology. However, these results are also of intrinsic interest for what they reveal about the contribution of various building characteristics to risk from airborne contaminants. A variety of parameters were varied, including building construction, heating, ventilating, and air-conditioning (HVAC) system design, and release characteristics, among others. Results of these simulations demonstrate the variability of exposure possible under different scenarios and, more particularly, the impact that HVAC design decisions can have on risk. Although a single building and restricted set of scenarios was investigated, several general conclusions could be drawn regarding factors, such as HVAC zoning and filter maintenance, that intrinsically contribute to vulnerability reduction.

This paper describes a decision-support framework assisting the design of nonresidential buildings with natural ventilation. The framework is composed of decision modules with input, analysis algorithms and output of natural ventilation design. The framework covers ventilation with natural driving force and mechanical-assisted ventilation. The proposed framework has two major assessment levels: feasibility assessment and comparison of alternative natural ventilation approaches. The feasibility assessment modules assess the potential of the site with the design proposition for natural ventilation in terms of wind, temperature, humidity, noise, and pollution conditions. All of the possible natural ventilation approaches and system designs are assessed by first applying constraint functions to each of the alternatives. Then the comparison of alternative approaches to natural ventilation continues by assessing the critical performance mandates that include energy savings, thermal comfort, acoustic control, indoor air quality, and cost. Approaches are finally ranked based on their performance.

Because of an increasing interest in the use of cold-formed steel for commercial and residential framing, both design and installation guidelines are needed. The wall framing, which typically consists of axial load bearing C-section studs, is laterally braced and attached at the bottom and top of the wall to a track section. The common bottom and top attachment consists of the wall stud and track of nominally the same cross-section depth. Because the nominal depths of the C-section and the track are similar, a tight connection is often not achieved and a gap occurs. The Standard for Cold-Formed Steel Framing—General Provisions specifies that the gap between the wall stud and track in a wall assembly must not exceed $1∕8\mathrm{in.}$ This gap dimension is consistent with the gap specified by ASTM C 1007. The value of $1∕8\mathrm{in.}$ is based on industry experience and practice but had not been experimentally verified. To explore both the stud-to-track connection strength and the aesthetic concerns associated with a gap between the axial load bearing stud and the track in a typical cold-formed steel wall assembly, a test program was initiated at the University of Missouri-Rolla. Based on the findings of the 54 wall assembly tests and short column tests performed in this experimental study, design guidelines are proposed for a typical wall stud assembly.

Presented herein are the details and results of an experimental study conducted to evaluate the performance of a proposed infill wall fuse system. The purpose of this system, referred to as the seismic infill wall isolator subframe (SIWIS) system, is to prevent damage to columns or infill walls due to infill-frame interaction through a “sacrificial” component or a “structural fuse.” The SIWIS system conceptually consists of two vertical and one horizontal sandwiched light-gauge steel studs with SIWIS elements in the vertical members. The experimental study presented here involves the in-plane lateral load testing of a two-bay three-story steel frame in three forms of bare frame, infilled braced frame, and pinned frame equipped with the proposed SIWIS device. In addition, a brick wall in-plane strength test and a series of component tests on three different designs for fuse element were conducted. In the conducted tests, the suggested technique initially engages the infill walls in seismic resistance of the frame, but ultimately isolates them. It is concluded, thus, that the proposed fuse system has the potential for the development of an effective way to reduce earthquake damage in framed buildings with infill walls.