Two-storey Building Research Articles

Central Processing Point Deployment for e-Healthcare Services Using Wireless Networks

In this paper, we present an approach to jointly minimize energy consumption of wireless transmitters and harmful interference on sensitive medical devices, and optimize the central controller placement for collecting data from transmitters. In particular, a multiobjective nonconvex mixed-integer nonlinear programming problem is formulated to optimize transmit power of wireless users and central processing point deployment along with guaranteeing minimized electromagnetic interference to comply with the immunity level of medical devices. To solve this problem, an important step is to convexify it, following which, we propose the use of a standard branch-and-bound algorithm to solve it. The solution is implemented in MATLAB using optimization interface Toolbox. We analyze the results numerically and consider different cases within a single floor of a hospital and a few scenarios for a two-storey hospital building. Our results show that the proposed approach offers improvement in throughput and guaranteed immunity for medical devices.

Impact, runoff and drying of wind-driven rain on a window glass surface: Numerical modelling based on experimental validation

This paper presents a combination of two models to study both the impingement and the contact and surface phenomena of rainwater on a glass window surface: a Computational Fluid Dynamics (CFD) model for the calculation of the distribution of the wind-driven rain (WDR) across the building facade and a semi-empirical droplet-behaviour model. The CFD model comprises the calculation of the wind-flow pattern, the raindrop trajectories and the specific catch ratio as a measure of the WDR falling onto different parts of the facade. The droplet-behaviour model uses the output of the CFD model to simulate the behaviour of individual raindrops on the window glass surface, including runoff, coalescence and drying. The models are applied for a small window glass surface of a two-storey building. It is shown that by far not all WDR that impinges on a glass surface runs off, due to evaporation of drops adhered to the surface. The reduction of runoff by evaporation is 26% for a typical cumuliform rain event and 4% for a typical stratiform rain event. These models can be used to provide the knowledge about WDR impact, runoff and evaporation that is needed for the performance assessment of self-cleaning glass or the study of the leaching of nanoparticles from building facades.

Comparative analysis on the seismic behaviour of unreinforced masonry buildings with flexible diaphragms

The paper reports a comparison among different methods of analysis and different numerical models to estimate the seismic behaviour of unreinforced masonry buildings with flexible diaphragms through the investigation of a reference masonry prototype. The prototype was a two-storey building tested on shaking table at the CNR-ENEA research centre of Casaccia (Roma, Italy) under increasing natural ground motions in order to analyse its seismic response from initial elastic conditions until moderate to extensive damage. A first numerical model was built with the finite element technique, and was employed to perform nonlinear static analyses (pushover). A second one was built based on the simplified macro-element approach and, being less computation demanding, was adopted to perform nonlinear dynamic analyses. The main results of all analyses are critically compared and discussed in order to investigate the effectiveness of both simplified models and analysis methodologies. Eventually, numerical results are compared with the available experimental data. The FE model is able to predict the damaged areas and the incipient collapse mechanism, as well as the collapse load. The macro-element model is able to predict the collapse load but, due to some limitations of the approach, a satisfactory reconstruction of the actual collapse mechanism was not obtained. Nevertheless, the simplified model is able to fairly accurately estimate the accelerations at the top floor measured in the tests.

Indoor radon measurements of the multi-storey buildings in Seoul, Korea

Most people are exposed to various kinds of indoor pollutants due to spending most of their time indoors. Unlike other anthropogenic pollutants of the indoor environment, radon gas is a naturally formed radioactive pollutant and it has been known as a second major contributor to lung cancer. However, most radon studies have focused on underground facilities and one-story buildings because the dominant source of indoor radon was known as the soil gas which was emitted from cracks or pores of the wall on the ground. Three study areas were selected for this research: the first and the second floor of a two-storey building (area A), the third floor of a newly built four-storey building (area B), and the 11th floor of a 15-storey apartment house (area C). Radon concentrations were measured by means of etched-track detectors (passive method) and by continuous measurements (active method). The active method was only used in area B because of continuous pump noise of the measuring device. Radon concentrations were monitored by the passive method for 3 or 4 months according to the study area. Continuous measurements were conducted for 3 months using the radon monitoring instrument (RAD7). The measuring protocol for the active method was ‘sniff’. The average radon concentrations determined by the passive and the active methods in area B were 2.9 and 1.8 pCi/L, respectively. The radon concentration measured by the passive method was 1.6 times higher than that measured by the active method. The average radon concentration in area C was 1.7 pCi/L (range 1.3–2.1 pCi/L) and slightly higher than that in area A (average 1.3 pCi/L with a range of 0.6–2.1 pCi/L). The results suggest that more detailed studies on the sources and rates of radon emissions are needed for multi-storey buildings.

Shaking Table Test of a Strengthened Full-Scale Stone Masonry Building with Flexible Diaphragms

An extensive experimental campaign has been conducted at EUCENTRE to understand the dynamic behavior of historic stone masonry structures and evaluate the seismic performance of selected strengthening strategies, aimed at improving wall-to-floor connections and in-plane diaphragm stiffness. Shaking table tests were performed of full-scale two-storey buildings in undressed double-leaf stone masonry with timber floor and roof. A first prototype (Building 1), representing a vulnerable building without antiseismic detailing and devices, was tested showing a response characterized by in-plane distortion of the flexible diaphragms and local out-of-plane failure mechanisms. In Building 2 the wall-to-diaphragm connections were improved, providing only a moderate in-plane stiffening of the wooden diaphragms. When subjected to shake-table testing, the strengthened building showed a global type of structural response without the occurrence of out-of-plane mechanisms. In the present paper the strengthening interventions on Building 2 are described, and the results obtained during the dynamic tests are illustrated, focusing on the response of the structure, the evolution of damage mechanisms during the tests, in comparison to the seismic performance of the first unstrengthened reference prototype response. The improvement of the connections proved to be very effective, increasing significantly the seismic capacity of Building 2 with respect to Building 1.

Thermal and comfort conditions in a semi-closed rear wooded garden and its adjacent semi-open spaces in a Mediterranean climate (Athens) during summer

The cooling effect in a courtyard's garden and in the adjoining ground- and first floor verandas, attached to the NNE side of a two-storey building is evaluated with measurements performed during a hot weather summer period in Athens. Results revealed a well defined and strong daytime cool island between the buildings rear garden (with about 85% canopy covering) and an air temperature reduction for the ground floor veranda, as compared with an urban square with low canopy coverage (about 15%), reaching a maximum air temperature reduction of 6.5 K during daytime. Compared with a nearby densely wooded park, the garden and the veranda were found 1–1.5 K cooler during 4 and 8 hours during daytime, respectively. Using the physiologically equivalent temperature thermal index with appropriate adjustments to local conditions, it was found that those two sites, compared with the urban square, were able to mitigate the extreme thermal stress conditions and to decrease the daily number of hours associated with strong thermal stress conditions. It is concluded that appropriately designed semi-open spaces in residential buildings, well known from vernacular architecture for their qualitative benefits, may be considered as positive bioclimatic pedestrian transitional elements in sustainable urban design for Mediterranean climates.

Traffic-induced vibrations of frame structures

Using the spectral element method (SEM), a 2-D numerical model of multi-storey frame structures has been developed. The model has been used to predict traffic-induced vibrations of two, six, and twelve-story concrete buildings measured along the route of a future metro line in Belgrade, the capital of Serbia. Vibration simulations of the six-storey frame match satisfactorily the measured dynamic response. However, there is a difference between numerical simulation and the actual measurements for the two-storey and twelve-story buildings. The results indicate a great potential of the proposed SEM to simulate ground-induced vibrations of frame buildings. However, more complex structural models should be developed to better replicate actual situations.

Ambient air pollution by mercury species at the urban station in Zabrze, Southern Poland

The study presents the initial results of semi-continuous measurements of atmospheric mercury species (Hg0, Hg2+ and particle mercury Hgp bound with PM2.5) in Zabrze obtained between January and December 2011. Zabrze is a city (190,000 inhabitants) within Upper Silesia Agglomeration, the most urbanised and industrialised part of Poland. Ambient air was sampled from the roof of the two-storey building of Institute of Environmental Engineering of the Polish Academy of Sciences (residential area). The measurements were performed using a Tekran 2537B mercury analyzer together with a 1130 Speciation Unit and a 1135 Hgp Unit. Hg2+ is captured in the unit 1130 (KCl-coated denuder), while Hgp is trapped onto a regenerable filter inside the module 1135. Hg0 remaining in the air stream is then directed into the 2537B mercury analyzer and detected using cold vapour atomic fluorescence spectrometry. The concentration of Hg0 (5-minutes data) was from 1.5 to 67.5 ng m–3, with 3.3 ng m–3 as a mean value. Hg2+ concentration (1-hour data) varied from <1 to 763 pg m–3, at arithmetic mean of 25 pg m–3. The concentration of Hgp (1-hour data) ranged from <1 pg m–3 to 4.8 ng m–3, on average 52 pg m–3. While the concentration of Hg0 did not diverge generally from the levels observed in urban areas of Western Europe and Northern America, the concentrations of two remaining Hg forms were higher. Their concentrations were higher in winter than in summer unlike the concentration of Hg0.

Test Research of Glubam and it's Engineering Application

Bamboo is an ancient building material, but it is rarely applied in the modern buildings nowadays. The German-Chinese House in EXPO 2010 Shanghai China is mainly made up of bamboo members; it fully demonstrates the ideas of sustainable development and environmental protection. The 8m high pavilion is a two-storey building which is 25m long and 10m wide, and its first floor is 250 m2 and second floor is 80 m2. The exterior structure of the pavilion is made up of 96 JULONG bamboo canes whose diameter is approximately 200mm, and the inner two storey structure is made up of glubam beams and columns which have a section of 300mmX400mm. Obviously the designer had applied both the good compression capability of the pure bamboo canes and the excellent bending capability of the glubam members in this structure. As there is no bearing capacity data of the glubam, several tests for the glubam members had been carried and thus a lot of useful data had been got, therefore some structure analysis had been done. It indicates that glubam is a good structural material, and as a friendly environmentally building material, it can be widely applied in building engineering.[

INVESTIGATION OF POWER LAW WIND EXPONENT WITHIN THE LOWER BOUNDARY LAYER AT ILE-IFE, NIGERIA.

A sound detection and ranging (SODAR) equipment installed on the roof of a two-storey building at the Department of Physics, Obafemi Awolowo University Ile-Ife, Nigeria (7.52 0 N and 4.52 0 E), 294 m height above mean sea level and about 20 m above the ground level has been used to study on continuous basis the planetary boundary layer (PBL) wind. Eighteen thousand (18000) sets of hourly averaged data for the wind speed from 30 m above the surface to 500 m height at 20 m intervals had been used to study the power law wind exponent α over Ile-Ife Nigeria. The data covered about two and half years (from June 2009 to December 2011). Exponent α was found to increase with height and decrease with surface wind speed. It was also discovered that α had both diurnal and seasonal variations. The values at daytime were lower than at nighttime and the wet months had higher values than the dry months. Its average for the dry months was 0.33 while the average for the wet months was 0.45.

Africanized honeybee stings: how to treat them

In 1956, Africanized honeybees (AHB) migrated from Brazil to other regions of the Western Hemisphere, including South, Central, and North America, except for Canada. Despite being productive, they are highly aggressive and cause fatal accidents. This study aimed to evaluate patients at the Clinical Hospital of Botucatu Medical School (HC-FMB) and to propose treatment guidelines. From 2005 to 2006, the clinical and laboratorial aspects of 11 patients (7 male and 4 female) and the anatomopathological aspects of one patient who had died in 2003 were analyzed. The age of the surviving patients varied from 5 to 87 years, with a mean of 42.5 years. The majority of accidents occurred in the afternoon, and the number of stings ranged from 20 to 500. The principal signs and symptoms were pain and local inflammatory signs, nausea, tachycardia, and vomiting. Biochemical findings presented increased levels of creatine phosphokinase, lactate dehydrogenase, and aspartate/alanine aminotransferase. An 11-year-old male patient died upon entering the attic of a two-story building where he was attacked by a swarm, receiving more than 1,000 stings. He was sent to HC-FMB where he was treated, but he died 24h later. Observed at the autopsy were erythematous-purpuric skin lesions besides necrosis at the sting locations, rhabdomyolysis, focal myocardial necrosis, tubular hydropic degeneration and focal tubular acute necrosis of the kidneys, myoglobinuria, and centrolobular necrosis in the liver. Accidents caused by multiple AHB stings always constitute a medical emergency. As there is no specific antivenom, we have developed guidelines, including first aid, drugs, and the proper removal of stingers.

A framework for automated assessment of post-earthquake building damage using geospatial data

Based on the triangulated irregular network (TIN) model, barycentric coordinates and random points, a new method was developed for more accurate characterization of 3D shape signatures of buildings using Light Detection and Ranging (LiDAR) data and Geographic Information System (GIS). The new method was applied to four simulated building models with flat, pent, gable and hip roofs to test the detection of changes in 3D building shapes in a post-earthquake scenario: (1) a three-storey building model becomes two-storey after losing the first floor; (2) a severe damage of a two-storey building model; and (3) a total collapse of a two-storey building model. The new method was then applied to real LiDAR data from four buildings in Harris County, TX, USA. All the changes in 3D shapes of the models and real buildings were successfully detected using 3D shape signatures. Sensitivity analyses were carried out to test the influence of LiDAR point density and new points in TIN triangles on 3D shape signatures. The results suggest that LiDAR point density of 0.5 point m−2 or higher can generate stable 3D shape signatures of buildings, and that the density of the new points in TIN triangles does not affect 3D shape signatures significantly. Built upon the new method and results, a framework was proposed for an automated assessment of post-earthquake building damage using geospatial data. A flowchart was presented to provide more details of the framework, and the advantages and limitations of the framework were also discussed. It is expected that the framework can be effectively applied to post-earthquake building damage assessment and other disaster scenarios that involve major changes in 3D building shapes.

Possibilities and comparison of structural component models for the seismic assessment of modern unreinforced masonry buildings

This paper addresses the possibilities of structural component models for the seismic assessment of masonry buildings using pushover analysis. The ultimate goal is to allow efficient design of new unreinforced masonry buildings in seismic areas. Different modelling strategies are presented and the implementation of a simple design tool based on structural component models is described in detail. The different approaches are applied to a two-storey building with regular plan and elevation, allowing for a comparison between them. The results indicate that macro-modelling using structural component models and pushover analysis are adequate approaches for the seismic assessment and design of unreinforced masonry buildings, as the tools require very low computational resources, allow easy interpretation of results and provide satisfactory accuracy.

Causes of structural failures of a building: Case study of a building at Oba-Ile, Akure

This article investigates the cause of the failure of some parts of a two-storey building under construction, in Oba-Ile, Akure, Ondo State, Nigeria. The article examines the effect of the quality of sand used for concrete production on the quality of concrete produced from them. The article also investigates whether the provided main and shear reinforcements in buildings complied with the provisions of the BS 8110. Site inspections were carried out, and concrete samples were taken. Many of the structural components were exposed, so as to determine the number of reinforcements in each structural element, the anchorage length of main reinforcement provided and the spacing of shear reinforcement. The field settling method was used to determine the percentage content of silt/clay impurity in the sand. The average silt/clay content of the sand was found to be 10.5 per cent, which is above the maximum 4 per cent value stipulated by the code. The results of both the destructive and non-destructive tests show that the average compressive strength of the concrete is 9.6 N/mm2, which is less than 20 N/mm2 specified minimum concrete strength for structural use. The anchorage length provided is less than the value stipulated by the code. The low quality of the concrete is due to the high percentage content of silt/clay in the sand used. From the above investigation, the possible cause of the collapse of the building is the provision of anchorage length less than required, spacing of shear reinforcement is less than required and, the poor quality of the concrete used for the construction.

Revitalization of Historical Building in Wrocław’s City Centre, Poland

Some aspects of the revitalization of the 14th century historical building are presented in the paper. The building was originally used as a poorhouse and a hospital for children. The original Gothic masonry building on the site was a two-storey building with a cellar, situated in a corner of two streets. In the middle of the 19th century the building was converted into a school and then the first large-scale demolition of the hospital’s Gothic walls took place. After the 2nd World War a school was also situated in the building, where it existed until the late nineties. The aim of the renovation process was to convert it into an exclusive office block. The design works were preceded by historical research and on-site investigations. Complex conversion of the object consisted in the reconstruction of the old building structure, creating the inner courtyard and covering it with a glass roof. In the existing part of the basement one of the longest single-nave vaults in Poland and the exquisite roof truss system with a lying bidding-rafter post deserved special attention during the renovation.

Independent People

Independent People

Twenty Years of Improvement in the Seismic Performance of Masonry Veneer Construction

A lot of clay has flowed through the kilns since the 1989 Newcastle earthquake. Several significant changes have occurred to make masonry veneer construction safer and stronger over this period, both in the methods of construction of the veneer and the understanding of the behaviour of the veneer panels. These changes have lead to the conclusion that masonry veneer construction can be reliably considered to provide some bracing resistance to a light timber-framed structure, even if only to resist its own inertial loads. Recent research undertaken at BRANZ has investigated the behaviour of full-scale brick veneer single- and two-storey buildings under slow static and dynamic cyclic loading. This paper describes the developments that have occurred since 1989 and this recent research that has provided the new confidence in the seismic performance of clay brick veneer.

Shaking Table Experimental Study on Diagnosis of Damage and its Evaluation in Steel Structure

The methods of diagnosis of damage through measuring the changes in dynamic structural properties have been intensively studied for many years now. On the contrary to mechanical or aeronautical engineering, however, the practical application of the methods in the case of civil engineering structures meets a number of difficulties indicating the need for further research. This concerns in particular the need for the shaking table investigations since the results of such tests are very limited. Therefore, the aim of the present paper is to show the results of the shaking table study conduced on a model of two-storey steel frame building. The 1.56 m high model structure was constructed of columns with cross section of mm. Damage was defined as a reduction in stiffness and introduced by replacing the columns with elements having mm cross section. Seven different structural damage cases described by different number of columns with the reduced cross section were considered in the study. During the shaking table experiment the base of the structure was excited under the sweep-sine loading. The results of the study show a characteristic decrease in the natural frequencies with the progression of damage. This trend has been especially observed for the first natural frequency, for which the decrease in the frequency value has been found to be uniform. The results of further analysis show the scattered values of the structural damping ratios without showing any relation with the level of structural damage.

Neural network-based simulation for response identification of two-storey shear building subject to earthquake motion

This article uses powerful technique of artificial neural network (ANN) models to simulate and estimate structural response of two-storey shear building by training the model for a particular earthquake. The neural network is first trained for a real earthquake data and the numerically generated responses of different floors of two-storey buildings as the training patterns. Trained ANN architecture is then used to simulate and test the structural response of different floors for various intensity earthquake data and it is found that the predicted responses given by ANN model are good for practical purposes. It is worth mentioning that although the simulation is done with numerically generated response data for particular earthquake, the idea may also be used for actual experimental (response) data.

Spatial to kinematically determined structural transformations

To understand the building design process and to help designers involved, the idea of a research engine has been developed: In this engine cyclic transformations take place between spatial and structural building designs. With this engine, a design process can be studied closely and subjected to improvement, and designers can be supported. To develop the engine, in this paper a part of it is studied, namely the transformation from spatial to structural design, which can be divided into four sub transformations: (1) from spatial design to structural topology; (2) from structural topology to mechanical model; (3) from mechanical model to finite element model; (4) from finite element model to design recommendations. For the first sub transformation, two different techniques are presented: Spatial–Structural Transformation Rules and Element Selection. For the second sub transformation, also two techniques are presented: Element Approach and System Approach. Where possible, data models in EXPRESS and process models in IDEF0 are used. For the third and fourth sub transformation, new procedures have been developed using data models in EXPRESS. To test the data and process models for all four sub transformations, a simplified two-storey building, derived from a real six-storey apartment building, is used as case study. It can be concluded that the developed sub transformations function well, related to their application in the research engine, and that their development raises new research questions that have to be solved in the near future.