Single-story Building Research Articles

Reserves of the bearing capacity of metal columns as part of a single-span frame with crane loads

The search for reserves of bearing capacity and improvement of the calculation of compressed-flexural metal columns is an urgent task. This makes it possible to more fully take into account the actual operation of structures and metal savings. An analysis of these and other issues is given in this paper on the basis of theoretical and experimental studies of life-size compressed-curved columns as part of a single-story and single-span industrial building with overhead cranes. The purpose of this work was to search for reserves of the bearing capacity of compressed-bent columns as part of the diameter of one-story single-span buildings with overhead cranes. As a result of the theoretical studies carried out, a method for calculating the stability of compression-bending columns as part of a cross section with crane loads has been developed. The technique takes into account the compatibility of the work of unevenly loaded columns in the frame and the shape of the deformation of the columns under the action of an active load. The estimated length calculated for frames with crane loads according to the proposed method is less than the estimated lengths according to current standards by 8-20%. To implement the tasks set in the experiment, a stand was developed and manufactured that allows testing the column as part of the frame and applying all types of vertical and horizontal loads to it. Experimental studies of full-scale compression-bending columns as part of a frame with the application of all loads that act on them (permanent, wind and crane) at different stages of the load, up to the exhaustion of the bearing capacity, made it possible to investigate the actual stress-strain state of the columns and their movement, bending of column base plates, development of current deformations in web flanges, local buckling of flanges and webs, general buckling of columns in the frame. For reconstructed industrial enterprises, a method for determining the reserves of bearing capacity for vertical load based on multiparameter loading of the diameter is proposed.

Seismic Retrofitting of Existing Industrial Steel Buildings: A Case-Study

Industrial single-storey buildings are the most diffuse typology of steel construction located in Italy. Most of these existing buildings were erected prior to the enforcement of adequate seismic provisions; hence, crucial attention is paid nowadays to the design of low-impact retrofit interventions which can restore a proper structural performance without interrupting productive activities. Within this framework, an existing industrial single-storey steel building located in Nusco (Italy) is selected in this paper as a case-study. The structure, which features moment resisting (MR) truss frames in both directions, is highly deformable and presents undersized MR bolted connections. Structural performance of the case-study was assessed by means of both global and local refined numerical analyses. As expected, the inadequate performance of connections, which fail due to brittle mechanisms, detrimentally affects the global response of the structure both in terms of lateral stiffness and resistance. This effect was accounted for in global analyses by means of properly calibrated non-linear links. Thus, both local and global retrofit interventions were designed and numerically investigated. Namely, lower chord connections were strengthened by means of rib stiffeners and additional rows of M20 10.9 bolts, whereas concentrically braced frames (CBFs) were placed on both directions’ facades. Designed interventions proved to be effective for the full structural retrofitting against both seismic and wind actions without limiting building accessibility.

A Review on Comparative Study between the Pre-Engineered Building and Conventional Steel Building

Abstract: In steel structure design the Pre-engineering building (PEB) system is a modern technology that provides economical, eco-friendly, and sustainable structures. The pre-Engineered Building (PEB) concept is a new conception of single-story industrial building construction. This methodology is versatile not only due to its quality pre-designing and prefabrication but also due to its lightweight and economical construction. This concept has many advantages over the Conventional Steel Building (CSB) concept of buildings with roof trusses. This paper mainly focuses on the PEB concept and CSB concept. The study is achieved by designing a Warehouse building as PEB and as CSB with the help of Staad Pro. The CSB is designed and analyzed by IS 800:2007 (LSM) and PEB is designed and analyzed by AISC 360:10. Keywords: Pre-Engineered Building (PEB), Conventional steel building (CSB), Structure analysis and Design, STAAD PRO V8i

Simulation for the thermal performance of super-hydrophilic fabric evaporative cooling roof based on experimental results

With characteristics of lightweight and simple construction, wet fabric roofs can achieve preferable cooling effects for top floor spaces of buildings leading to reductions of building air conditioning. However, the potentials of applying them to real projects are not well recognised, because we lack simulation models to precisely predict the thermal performance of the fabric roof. This paper aims to investigate the dynamic performance of a super-hydrophilic fabric roof for a single-storey building under the climates of Beijing based on an empirical model. Initially, a dedicated experimental system was built to measure the fabric's actual evaporation rate under a wide range of parameters including inlet air dry-bulb temperature, humidity, velocity, and imposed radiation intensity. The test data were used to develop an empirical model of evaporation rate by the symbolic regression method. The discrepancy between prediction and measurement was found to be within 90%, representing the model's accuracy was satisfactory. Furthermore, by incorporating the empirical model, an EnergyPlus program with an Energy Management System module was developed to predict the thermal performance of a single-storey building. The results showed that internal and external surface temperatures of the fabric roof can be reduced by up to 15.7 °C and 11.8 °C respectively. We concluded that the proposed fabric roof has great potential of cutting cooling load by 34%–44% in average compared to traditional roofs. This paper develops an empirical model for estimating the wet fabric's evaporation rate and paths a way for evaluating the cooling potential of fabric roofs for buildings in various climates.

Systematically incorporating spectrum-selective radiative cooling into building performance simulation: Numerical integration method and experimental validation

Besides highly reflecting solar energy, the spectrum-selective radiative cooling materials (RCMs) dissipate heat to outer space especially through the atmospheric window (e.g., 8–13 μm) and achieve sub-ambient temperature under direct sunlight. Not only potentially contributing to Earth’s heat rebalance, the daytime radiative cooling technology but also presents promising applications to building facades as a passive ‘zero-energy’ cooling method. Although there has been a large amount of radiative cooling materials developed recently due to the wavelength scale photonic material design, the wide application of radiative cooling materials to buildings faces challenges, including the barriers of scalable manufacturing and the lack of industry acceptable simulation tools for designers and engineers. Deliberating the major impacting factors such as moisture variation in atmosphere, this study designed a systematic strategy of incorporating spectrum-selective radiative cooling with whole-building performance simulation by developing a new long-wavelength radiation spectrum integral module (LRSIM) suitable for being built into the state-space model, like the DeST tool. Reduced-scale controllable experiments have validated the accuracy of LRSIM, giving < 3% deviation for the spectrum-based long-wavelength radiation calculation. Subsequently, experimental results from full-scale model houses were utilized to further validate the DeST tool embedded with LRSIM for building application of spectrum-selective radiative cooling materials. Indoor air temperature deviation < 1 °C was observed between the simulated and measured data, indicating the compelling prediction power of the integrated tool for radiative cooling modeling. Simulation analysis to a single-story commercial building at six locations around the world has shown energy-saving potential of 14–42% for an example radiative cooling material. Different from other customized plug-in integration, the experimentally validated DeST with built-in LRSIM will provide architecture designers and application engineers a general-purpose and easily-usable tool for promoting adoption of radiative cooling technology in buildings.

Modelling and Seismic Response Analysis of Non-residential Single-storey Existing Precast Buildings in Italy

ABSTRACT Old precast buildings are often characterized by poor detailing that may hamper the structural performance, particularly in the case of earthquakes. This is essentially related to: (i) a limited past knowledge of seismic design and behaviour, also reflected in past building codes; (ii) the evolution of seismic zonation of the Italian territory. The aim of this work is to assess the probabilistic seismic vulnerability with respect to the usability preventing damage and global collapse performance levels of four existing single-story precast buildings designed in accordance with past Italian building codes from 1960s to 1990s in three sites with increasing seismic hazard.

Blasting Vibration Monitoring and a New Vibration Reduction Measure

Vibration waves generated by blasting can cause shock to buildings. Different responses occur in different parts of the building. Therefore, a single standard is inaccurate. At the same time, methods to reduce vibration are needed. In this paper, the variation of peak particle velocity (PPV) and principal frequency was analyzed. The energy variation of blast vibration waves was analyzed by wavelet packet decomposition. A numerical model was established to verify the new vibration reduction measure. The results showed that the PPV on the walls increases with their height. The PPV and principal frequency of different structures of single-story brick-concrete buildings are different. The amplification factor of PPV does not change much when the principal frequency ratio is larger than 0.75. Measuring points at different heights have different sensitivities to blasting vibration waves of different principal frequencies. Therefore, different structures will respond differently to the same blasting operation. The PPV can be reduced by waveform interference. However, the cycle of blasting vibration waves decreases with increasing distance. Therefore, it is necessary to determine a reasonable interval to reduce the PPV. This requires further research.

Effect of the asymmetry level on collapse margin of torsionally stiff single-story buildings based on FEMA P695 methodology

The stiffness of many lateral force resisting elements depends on their strength. The early studies indicated a relatively better performance of the strength symmetric design model (zero-strength eccentric model) compared to other design models. However, further investigations claimed that the balance design model could endow the best seismic performance in asymmetric structures. In this study, single-story structural models with varied asymmetry levels and two cases with square and rectangular plans were considered. The models were evaluated by FEMA P695 methodology in various centers of mass, stiffness, and strength positions, including a balance model, strength symmetric, and code design model. The adjusted collapse margin ratios in these models were calculated as the performance index. The results showed a better seismic performance of the balance design model for the normalized yield eccentricity (ed/A) values below 15%. For ed/A values more than 15%, strength symmetric design model showed a superior seismic performance, while the code design model presented the weakest seismic performance. Evaluation of the seismic design parameters indicated that the code design model may not provide a satisfactory acceptance criterion with the existing standards, which necessitates re-evaluation of its design parameters.

Buoyancy-driven natural ventilation characteristics of thermal corridors in industrial buildings

The continuous setup of heating plants such as kilns and boilers may form thermal corridors in industrial buildings resulting in high air temperature, which could be harmful to workers. To solve these problems, this study presents an investigation of the buoyancy-driven natural ventilation of a high-temperature corridor via computational fluid dynamics (CFD) simulation. First, a field measurement was conducted in a typical thermal corridor of a ceramic factory to define the boundary conditions for the simulation. Then, a CFD model was established and validated using reduced-scaled model experimental data. Next, the flow and temperature fields of the thermal corridor under buoyancy-driven natural ventilation were examined using the verified model. It was shown that the natural ventilation in the side corridor is generated by an asymmetric heat channel, and the flow in the main corridor belongs to the natural convection of a semi-closed square heating cavity. Finally, the single-story industrial building aspect ratio was fixed at 3.3, and five different parameters of building and heating plant setups on the natural ventilation in corridors were analysed. For example, the heat source and air opening aspect ratios varied from 12.5 to 50 and from 25 to 100, respectively. The results indicated that the height of the heat source bottom has a more significant effect on the indoor thermal environment than other situations. The maximum ventilation flow rate was observed at the heat source position zs/H = 0.04 and opening position H0/H = 0.05. When the overhead height zs/H reached 0.08, the flow in the main corridor turned to a symmetric heat channel, and the temperature in this region decreased sharply. This research can provide a reference for the natural ventilation design of high-temperature corridors in factories.

Concentrated radiative cooling

A fundamental limit of current radiative cooling systems is that only the top surface facing deep-space can provide the radiative cooling effect, while the bottom surface cannot. Here, we propose and experimentally demonstrate a concept of “concentrated radiative cooling” by nesting a radiative cooling system in a mid-infrared reflective trough, so that the lower surface, which does not contribute to radiative cooling in previous systems, can radiate heat to deep-space via the reflective trough. Field experiments show that the temperature drop of a radiative cooling pipe with the trough is more than double that of the standalone radiative cooling pipe. Furthermore, by integrating the concentrated radiative cooling system as a preconditioner in an air conditioning system, we predict electricity savings of >75% in Phoenix, AZ, and >80% in Reno, NV, for a single-story commercial building.

A Semi-Active Control Technique through MR Fluid Dampers for Seismic Protection of Single-Story RC Precast Buildings.

The work proposes an innovative solution for the reduction of seismic effects on precast reinforced concrete (RC) structures. It is a semi-active control system based on the use of magnetorheological dampers. The special base restraint is remotely and automatically controlled according to a control algorithm, which modifies the dissipative capability of the structure as a function of an instantaneous dynamic response. The aim is that of reducing the base bending moment demand without a significant increase in the top displacement response. A procedure for the optimal calibration of the parameters involved in the control logic is also proposed. Non-linear modelling of a case-study structure has been performed in the OpenSees environment, also involving the specific detailing of a novel variable base restraint. Non-linear time history analyses against natural earthquakes allowed testing of the optimization procedure for the control algorithm parameters, finally the capability of the proposed technology to mitigate seismic risk of new or existing one-story precast RC structures is highlighted.

Investigation of the Stress-Strain State of a Steel Column Base Connection for Seismic Regions

Currently, the main type of connection between a steel column and a reinforced concrete foundation is a steel base, which is often economically unprofitable due to its size, number or diameter of anchor bolts. Not only in Armenia, but also in most countries, a steel base is the main type of connection between a steel column and a reinforced concrete foundation. The usage of other types of connections is associated with both new calculation methods and technological problems. The possibility of computation and design of the connection of a steel column with a reinforced concrete foundation in seismically active regions using shear studs is considered in this work, a reinforced concrete section with longitudinal reinforcement is used for this type of connection which ensures a smooth transfer of forces from the column to the foundation. Based on the example of the connection of a single-story industrial building column shows the change in the stress-strain state of the connection under axial force and bending moments for seismic regions. Not only the feature and construction technology of the connection considered in the work, but also proposes a calculation method with future possibility of its subsequent inclusion in the building codes of the Republic of Armenia.

An Evaluation of the Performance of a Ground-to-Air Heat Exchanger in Different Ventilation Scenarios in a Single-Family Home in a Climate Characterized by Cold Winters and Hot Summers

In the present study, the real-world performance of a ground-to-air heat exchanger (GAHE) was analyzed in the Polish climate which is characterized by warm summers and cold winters. The heat exchanger’s performance was monitored over a period of three years (2017 to 2019), and real-world conditions were compared with a Typical Meteorological Year (TMY). The aim of the study was to assess the exchanger’s energy-efficiency potential in various ventilation scenarios in a single-family home under variable real-world conditions, rather than to simply determine its heating and cooling capacity. The analyzed single-family home was a modern, single-story building with a usable floor area of 115 m2. The building’s thermal insulation and airtightness met stringent energy-efficiency standards. Energy consumption in a building equipped with a natural ventilation system was compared with three other scenarios: ventilation coupled with a GAHE, mechanical ventilation with heat recovery and a high-efficiency heat exchanger (HE), and mechanical ventilation with heat recovery coupled with a GAHE. Sensible heating and cooling loads were calculated based on standard ISO 13790:2008, and latent heating and cooling loads were also included in the energy balance. During the year, the GAHE generated around 257.6 W of heating energy per hour and 124.7 W of cooling energy per hour. Presented results can be used to select the optimal HVAC system scenarios for engineering projects as well as private investors.

Modeling of joint work of steel beam constructions with reinforced concrete ribbed floor slabs

Traditional methods of calculation of beam constructions of floors and coverings of industrial buildings assume their consideration when calculating separately from the frame structures, in particular, reinforced concrete slabs, without taking into account their joint work, which leads to a significant margin of safety. Today in Ukraine there is a significant number of industrial buildings and structures that need strengthening and reconstruction.&#x0D; In this regard, of particular importance are studies of the actual load-bearing capacity of the frames of single-storey and multi-storey industrial buildings, and both in the reconstruction and in new construction, the results of which will significantly reduce costs and more rationally design structures.&#x0D; At the same time, one of the most relevant areas is the study of the joint work of metal load-bearing structures with prefabricated reinforced concrete structures of rigid disks of coatings and floors in their calculation.&#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; Moreover, in the national building codes, as well as in the educational and methodological literature, the calculation methods of taking into account the joint work of such constructions are not fully covered.&#x0D; The purpose of this work is to estimate the reduction of mass of the metal beam structure in its calculation in bending, taking into account the joint work with the rigid disk of the floor consist of precast concrete.&#x0D; As part of the study, the calculation of the floor beam according to the traditional calculation scheme - without taking into account the joint work with the floor slab, the calculation of its cross-section taking into account the joint work with floor slabs and experimental numerical study of the floor by the finite element method. Modeling of the floor fragment was performed in the software packages "SCAD Office" and "LIRA CAD 2019".&#x0D; Numerical research is aimed at verifying the feasibility of using the calculation methodology of DBN B.2.6-98-2009 to determine the effective width of the shelf when calculating the T-sections for prefabricated reinforced concrete slabs, which are included in the joint work with the floor beams.&#x0D; A comparative analysis of the obtained cross-section of the beam with the beam which was previously calculated by the traditional method of calculation in stresses in the most dangerous cross section and the total mass of the beams.&#x0D; According to the results of the analysis, the correctness of the application of the above normative method for determining the effective width of the shelf of T-bending reinforced concrete elements was confirmed.

RESEARCH ON STRUCTURAL EFFECTS OF BRACING SYSTEMS ON THE WORKING OF STEEL FRAMEWORK OF SINGLE-STOREY INDUSTRIAL BUILDING IN VIETNAM (PROJECT SURVEY IN HO CHI MINH CITY, VIETNAM)

In this article, the authors have investigated common types of bracing such as the parallel single bracing, the triangle bracing and the cross-bracing from forming, arrangement to an analysis of advantages shortcomings to find the right configuration for a steel single-story industrial building in Vietnam.

Wall-diaphragm interactions in seismic response of single-story building systems

The objective of this paper is to investigate the seismic time history response of single-story buildings with a wide range of wall and roof diaphragm periods and ductility. Current design specifications, e.g., ASCE 7-16, are transitioning from accounting for inelasticity in only the vertical lateral force resisting systems, i.e., the walls, to including inelasticity in the horizontal lateral force resisting system, i.e., the roof diaphragm. It is not clear if the wall and roof inelasticity can be considered independently, nor if they can utilize their own seismic response modification coefficients. More fundamentally, the basic manner in which stiffness, mass, and ductility of the wall and roof interact is not fully understood. Here, a single-story building is approximated with a reduced order mass-spring model and parameters are varied so that a wide range of wall periods, diaphragm periods, and wall and diaphragm inelasticity are explored. The model is imposed to vibration analyses, elastic time history analyses, and inelastic time history analyses. The results show clear regimes where the wall and diaphragms interact, and those where the response is largely independent. When inelasticity occurs the ductility demands can be significant for the building component, wall or diaphragm, that initiates the yielding, and greater than traditionally expected. The model results are compared to current and proposed provisions for predicting force and ductility demands and conclusions are drawn with respect to the accuracy of available methods.

Modelling issues and pushover response of singlestory older steel buildings

AbstractThe paper describes a study concerning the seismic response of some typical non‐residential single‐story older steel buildings. To this end, the design of two archetype buildings was simulated according to structural codes and standards of practice used in Italy in the 1980s‐1990s. The basic structural layout was assumed to be made of trussed portals in the transverse direction and concentric braces in the longitudinal direction. In the direction of the trussed portals, two alternative structural options were considered: (a) a pinned column base with moment action provided by the truss, and (b) a semi‐continuous column base with a pinned connection between the truss and the column top cross section. 3D finite element non‐linear models of the two case study structures were built. The model included the main frame members, some critical connections and explicit representation of fracture propagation for braces. Results from non‐linear static analysis are then presented and discussed. The paper highlights differences in the structural response due to differences in the selected design options, comparing both global and local response results.

Discrete Optimum Design of Planar Steel Curved Roof and Pitched Roof Portal Frames Using Metaheuristic Algorithms

Portal frames are single-story frame buildings including columns and rafters, and their rafters can be either curved or pitched. These are used widely in the construction of industrial buildings, warehouses, gyms, fire stations, agricultural buildings, hangars, etc. The construction cost of these frames considerably depends on their weight. In the present research, the discrete optimum design of two types of portal frames including planar steel Curved Roof Frame (CRF) and Pitched Roof Frame (PRF) with tapered I-section members are presented. The optimal design aims to minimize the weight of these frame structures while satisfying some design constraints based on the requirements of ANSI/AISC 360-16 and ASCE 7-10. Four population-based metaheuristic optimization algorithms are applied to the optimal design of these frames. These algorithms consist of Teaching-Learning-Based Optimization (TLBO), Enhanced Colliding Bodies Optimization (ECBO), Shuffled Shepherd Optimization Algorithm (SSOA), and Water Strider Algorithm (WSA). Two main objectives are followed in this paper. The first one deals with comparing the optimized weight of the CRF and PRF structures with the same dimensions for height and span in two different span lengths (16.0 m and 32.0 m), and the second one is related to comparing the performance of the considered metaheuristics in the optimum design of these portal frames. The obtained results reveal that CRF is more economical than PRF in the fair comparison. Moreover, comparing the results acquired by SSOA with those of other considered metaheuristics reveals that SSOA has better performance for the optimal design of these portal frames.

НЕСУЩАЯ СПОСОБНОСТЬ ФЛАНЦЕВОГО СОЕДИНЕНИЯ БАЛОК. ПОКРЫТИЕ ОДНОЭТАЖНОГО ПРОМЫШЛЕННОГО ЗДАНИЯ (ОПЗ) С УЧЕТОМ ЕГО ГРИБОВИДНОСТИ

The article deals with issues related to the analysis of steel frame structures. The subject of the study is the construction sector. The object of research is flanged joints of beams of coverings of one-storey industrial buildings. In order to achieve these goals, the following methods are used: analysis, synthesis, description, generalization and comparison. According to the results of the work, the features of forming the quality of interaction between flanged joints and high-strength bolts in the form of a nodal connection of coating beams are determined. Additionally, the analysis of features during the design work and production of flanged connections used for the implementation of popular design solutions for steel cross frames of single-storey buildings is carried out. The main directions of analysis of the state of steel structures in the presence of signs of deformation (mushroom shape) of the flange connection are disclosed. The obtained data helps to optimize the composition of structural reinforcement elements, as well as reduce the level of labor intensity in the production and installation of flange joints of single-storey buildings’ coating beams. In the course of the study, an experiment is conducted in which the principle of symmetry is used. The unidirectional connection in and between nodes is modeled using the elements considered. In this case, it is necessary to mention the phenomenon of the adhesive effect of the nodes during compression and the lack of adhesion during tension. The model takes into account the physical nonlinearity of the material properties, the behavior of which is set by bilinear dependencies under load

Seismic response and design of steel multi-tiered concentrically braced frames of the conventional construction category in moderate seismic regions of Eastern Canada

This study examines the seismic behaviour of steel multi-tiered concentrically braced frames (MT-CBFs) of the conventional construction category (Type CC) in moderate seismic regions of eastern Canada and proposes a new seismic design method for such structures. A total of 32 prototype MT-CBFs part of a single-storey building are selected and designed in accordance with the 2019 Canadian steel design standard (CSA S16-19) provisions for Type CC structures, excluding the design requirements prescribed for frames taller than 15 m, namely the amplification of seismic forces varying by the frame height and the amplification of the column factored seismic force. Nonlinear response history analyses are then performed to examine their seismic response. The results confirmed that tiers experience limited lateral deformation, intermediate horizontal struts are required between tiers, and columns are subjected to combined axial force and bi-axial bending, which in some cases led to column buckling. The results are used to propose a new seismic design method in the framework of CSA S16.