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In this paper, the numerical model of the tornado generator is established by using the computational fluid dynamics (CFD) method. The radar observed wind profiles of Spencer tornado (1998) are used as inlet boundary condition to form tornado wind field, and the influence of surface roughness is taken into account. This method is used to generate the tornado wind field with the same intensity as recorded in our country, and the wind load characteristics of low-rise building located in different positions in the tornado wind field are analyzed. Then the finite element model of the building is established by ANSYS software, and the building is considered as steel frame-steel plate composite wall structure, which rationality of the finite element model is determined by the modal analysis. The one-way fluid structure interaction method is adopted to transfer the tornado load to the surface of the finite element model, and the displacement response, deformation and damage state of the wall surface and roof surface of the building in different locations of the tornado wind field are analyzed in detail.

In this paper, prior to the structural analysis of R/C shells, the loading tests of R/C arch were performed. Considering the melting of a snow on south side, an applied loading was only one half of the arch. Therefore, the loading direction was vertical due to the snow load. As the results, the more the loading points were, the larger the ultimate strength grows independent height of rise. The axial strain in low rise arch was larger than that in high rise arch.

Buildings that incorporate masonry structure in countries with high seismic values are restrained by the norms in terms of force, to be used as plain masonry taking into account their fragile behaviour under alternating actions. In order to improve the masonry behaviour under seismic actions, an association of plain masonry with reinforced concrete was made to reach confined masonry with columns and belts, reinforced core masonry, or reinforced void masonry, etc. Consequently the research began on the autoclaved cellular concrete (ACC) masonry behaviour in the case of buildings erected in seismic areas and was focused upon the analysis of autoclaved cellular concrete (ACC) masonry with vertical hollows confined with disperse reinforced concrete when applied in low rise masonry buildings and which are situated in low seismic areas. The research was also justified by the fact that gas formed concrete exhibits several benefits as compared to brick masonry, namely: better thermal insulation, less manual work, reduced weight and implicitly lower seismic loads. The association of autoclaved cellular concrete (ACC) with disperse reinforced concrete in the case of confined masonry leads also to the removal of formwork and of reinforcement cutting. In this context the research is mainly concerned with the behaviour of autoclaved cellular concrete (ACC) masonry confined with columns and belts of steel fibre disperse reinforced concrete, both from theoretical and experimental viewpoint.

This paper presents the assessment results and structural retrofitting of SPS Building. The building is a three story reinforced concrete structure with a mezzanine floor for a storage. The building was an office building with a live load of 2.5 kN/m2 and then the building function changes to be an industrial building with a live load of 10 kN/m2. The existing concrete and rebars tensile strength, structural member dimensions and configuration were assessed before structural analysis and redesign were done using a commercial software. It is found that the average concrete strength is about 11 MPa and most of existing structural members are less flexure and shear capacity. Therefore, an external flexure and shear strengthening using external bolted steel plates were applied to those members with grouting materials to fill the gaps between the steel plate and existing structural members. A strength evaluation using direct loading with a maximum water depth of 1000 mm over an area of 60 m2 to represent the live load of 10 kN/m2 was conducted to ensure the retrofitting method works well. The test results show that measured deflections of beams and slabs are still less than the maximum deflection limits. This indicates that the strengthening system using external bolted steel plates can improve the member capacity to support the new design loads.

Rainfall is seldom addressed in the analysis of climates for building design, usually neglected for building thermal performance calculations, and there is very little research about its potential cooling effect. This research aims to estimate and compare the influence of natural rainfall on the thermal and energy performance of a low-rise building in diverse locations of the hot humid tropics to assess its significance. Through whole building simulations in WUFI Plus , a parametric study based on rain intensity is conducted to estimate the hygrothermal performance of a small building (free-running and air-conditioned) at wet, wet-dry and dry locations of the Tropics. Taking a holistic approach, this study observes aspects which are seldom regarded in thermal and energy simulations, like impacts to the outdoor environment and the role of water; and makes a closer approximation to reality than previous research which observes rain events only during daytime and in relation to isolated building components. The results show that rain can have an important cooling influence, although is usually more appreciable to the exterior of the building than to the interior. When the effect of rain is neglected, the total heat transfer per unit area from all outdoor surfaces to the surroundings can be overestimated by 20% in a rainy month and by 10% in a year; as well as by 7% in a rainy month and by 5% in a year from all indoor surfaces to the indoor air. Maximum temperature reductions due to rain can be 7.4 °C for outdoor surfaces, 1 °C for indoor surfaces, 0.4 °C for indoor air temperature and 0.5 °C for indoor operative temperature. The differences in thermal and energy performance result from consumption of relatively small amounts of rainwater (up to 67 kg in a rainy month and up to 448 kg in a year), which gives an idea of the potential of the rainwater surplus in the humid tropics for natural cooling in buildings and urban sites.

Frame systems are the preferred structural systems in most seismic regions, where they are sometimes also combined with braces or walls. On the other hand Chile, one of the most seismically active countries in the world, is an exception to this practice. Any Chilean residential building higher than 5 stories is almost completely made up of reinforced concrete shear walls. Surprisingly, only 2% of the residential building inventory subjected to the 2010 Chile earthquake (M w 8.8) suffered severe damage, even though many structures were affected by ground accelerations larger than those prescribed in the Chilean seismic design code. This observation suggests that there is a large (and unintended) overstrength in this type of buildings. In a previous study, the authors showed that some of the traditional sources of overstrength mentioned in the literature could explain the lack of damage in low rise buildings but not in taller structures. Motivated by this observation, representative tall buildings were reanalyzed using more realistic models (e.g., flexural capacity of the walls assessed by fiber models) in order to get more insight into their actual seismic capacity. Two actual buildings of 17 and 26 stories that survived with no damage the 2010 Chile earthquake were analyzed by response history analysis. Results show that consideration of wall flanges (usually omitted in practice) cannot explain the lack of damage. On the other hand, it is observed that good performance might be a consequence of possible foundation uplift. Finally, the analyses also suggest that, even when there is no damage, elastic analysis has limitations to reproduce the actual observed behavior.

A three dimensional numerical wind tunnel based on the Navier-Stokes equations for viscous, incompressible fluid and LES method is established. Incoming wind field is generated based on the AIJ guidelines (2004). The numerical wind tunnel is validated against experimental results. A low-rise building with green roof is tested in the numerical wind tunnel. The results show that the green roof reduces the drag force of the building, cuts down the fluctuation near the roof, but has insignificant effect on the time-averaged velocity field.

Construction is a sector that consumes various materials which comes from many sources. Cement and steel (i.e. rebar) part of material used in construction, are combined forming a material called reinforced concrete. In general, reinforced concrete is closely associated with the structure of the building, both low rise building and high rise building structure. In practice, reinforced concrete usage as structural material becomes a strategic issue in the effort to support green construction, especially with regard to the exhaust gas emissions of carbon dioxide (CO 2 ). A carbon dioxide (CO 2 ) emission in the use of reinforced concrete is produced by the use of fuel in concreting equipment such as tower cranes and concrete pump. The purpose of this research is to obtain potential factors for the source of carbon dioxide emissions (CO 2 ). The research object was carried out on several high rise buildings. The definition of high-rise building in this research is a building with a height of 40 m or higher. The sampling method used in this research is random sampling, while the analysis in this research used a descriptive analysis. The research findings show that there are seven factors that could potentially be a source of carbon dioxide emissions (CO 2 ) in the concreting of reinforced concrete at a high rise buildings. These seven factors are scope, time, cost, quality, resources, procurement and material transfer.

This study investigates the overstrength factor of reinforced concrete frame designed according to EC2 and EC8. There are two families of building considered in this study, i.e: regular and irregular in elevation with setback. Each family are designed to gravity load only and designed to resist seismic load with medium ductility and high ductility class. Therefore, in total, there are 6 frame models are considered in this study. The nonlinear static analysis or push over analysis is used to evaluate the overstrength factor of the frame models. It is found that, the geometry and ductility supply of the frames effect the overstrength factor.

A series of aerodynamic experiments were conducted to measure the surface pressures on tandem arranged low-rise buildings models with variant roof types in the wind tunnel. An electro-scan valves system was used to get the simultaneous pressures distribution on the models. With these conditions, the characteristics of surface pressures were detail calculated and compared. The results shown, the mean wind pressures on the low rise-to-span ratio models will lower then the higher ratio ones. But the fluctuating and peak pressures on the roof, especially at the corners, will be increased. About the shielding effect, it will reduce the surface pressures and the structural loadings. But in the cases of small gap between buildings, the peak pressure will be increased at side wall and roof corners of buildings. Over all, for the different types of roofs, the shielding effects on gable roof models are most evident and the arch roof models are less. For the dome-like roof models, the shielding effects are trifling. The designer may take consideration above these characteristics and benefited to optimize their structure design of the roofs.

This paper presents the vulnerability of public buildings in Sabah which are subjected to earthquakes from Sumatra and the Philippines. Tremors in Peninsular Malaysia and East Malaysia due to Sumatra and Philippine earthquakes have been reported several times. Engineers are concerned of the seismic vulnerability of public buildings due to lack of earthquake consideration in Malaysia‟s building design procedure. 8 (eight) reinforced concrete buildings which are mostly categorized as moment resisting frames has been selected for vulnerability study. A case study has been conducted on low rise, medium rise, and high rise buildings. The buildings are analyzed using Finite Element Modeling (FEM) under different types of analyses including Time History Analysis (THA) considering low to medium earthquake intensities. Different intensities of earthquake load, 0.05g, 0.10g, 0.15g and 0.20g are applied to the structures to know the maximum allowable earthquake load intensities for the buildings. In the non-linear analysis of modal frames, it indicates that most of the buildings are categorised in the moderate damage level where there is no structural damage but some non-structural damage are expected. The performances of the structure are shown by the yield point at beam-column connections where the internal forces at beam elements exceed the design capacity of the beams. The Labuan Airport building was performed the early yielding point at 3.85 sec for column element at intensity 0.05g. The study indicates that the plastic hinge initially formed on the column at the lower storey level for both low and high rise building frames.

At present a number of techniques for artificial strengthening weak foundation soils have been developed and implemented, most of them having poor efficiency due to expensive materials and equipment used. Therefore, studying and developing new ways to improve soil bearing capacity is an urgent task. The paper presents the experimental study of one of the ways to improve soil bearing capacity and stability through introduction of a sandy pile reinforced vertically along the contour with a geosynthetic permeable element (geogrid CCP 30/30 – 2.5). A technique for determining the temporal strain condition of the given structure has been developed after the linear theory of viscoelasticity. Theoretical calculations for the vertical movements of the pile body, comparable with the results of in-situ tests are presented.

To study the earthquake response of RC infilled frame structures with variable wall opening, 3-D computer models were made for 3, 4, and 5 storey typical hotel buildings consisting of six frames of 3 bays. In X-direction, the middle bay was open and the side bays were in-filled with full (solid) walls. In Y-direction, the interior walls consisted of door opening in the corner and the exterior walls consisted of window openings with variable ratios of 20%, 40%, 60%, 80%, and 100%. Prior to modeling the 3-D structure, 2-D validation models using diagonal strut and shell element were made based on test results of simple infilled frames with various openings. For the strut model, the wall with opening was modeled using diagonal strut of reduced width. For the shell element model the wall was modeled as is with gap element at the interface between the frames and the wall. Considering crack development and non linear stress-strain relationship of the materials, the lateral load-displacement diagrams of the shell element models fit the test result better than the strut ones. Models with lintels around the wall openings were also created for validation and the results show that lintels stiffen the frame and strengthen the wall around the openings. The shell element model was then used to create 3-D models of the hotel building with lintels around the wall openings. Analysis and design of the 3-D models show that the earthquake responses of RC frames infilled with walls of opening ratios 20% to 60% are significantly stiffer and stronger than that without infill wall. However, the contribution of infill walls with 80% opening in reducing storey drift and frame reinforcement was much smaller. Accordingly, the infill walls with opening ratios of less than 80% should be considered in the structural modeling to obtain a more accurate analysis and efficient design.