Low-rise Buildings Research Articles

An Algorithm for Generating Outdoor Floor Plans and 3D Models of Rural Houses Based on Backpack LiDAR.

As the Rural Revitalization Strategy continues to progress, there is an increasing demand for the digitization of rural houses, roads, and roadside trees. Given the characteristics of rural areas, such as narrow roads, high building density, and low-rise buildings, the precise and automated generation of outdoor floor plans and 3D models for rural areas is the core research issue of this paper. The specific research content is as follows: Using the point cloud data of the outer walls of rural houses collected by backpack LiDAR as the data source, this paper proposes an algorithm for drawing outdoor floor plans based on the topological relationship of sliced and rasterized wall point clouds. This algorithm aims to meet the needs of periodically updating large-scale rural house floor plans. By comparing the coordinates of house corner points measured with RTK, it is verified that the floor plans drawn by this algorithm can meet the accuracy requirements of 1:1000 topographic maps. Additionally, based on the generated outdoor floor plans, this paper proposes an algorithm for quickly generating outdoor 3D models of rural houses using the height information of wall point clouds. This algorithm can quickly generate outdoor 3D models of rural houses by longitudinally stretching the floor plans, meeting the requirements for 3D models in spatial analyses such as lighting and inundation. By measuring the distance from the wall point clouds to the 3D models and conducting statistical analysis, results show that the distances are concentrated between -0.1 m and 0.1 m. The 3D model generated by the method proposed in this paper can be used as one of the basic data for real 3D construction.

Probabilistic thermal analysis and phase transition temperature optimization for low-rise residential buildings with temperature-adaptive radiative cooling roofs

This paper conducts an optimization study on the energy performance of applying temperature-adaptive radiative cooling (TARC) coatings as building roofs. To provide guidance for the application of TARC roofs, a method for determining the optimal phase transition temperature of TARC coatings for application in buildings is proposed. Then, the thermal performance of the TARC roofs is analyzed for buildings located in five different climatic zones in China based on the probability density function and cumulative distribution function. Finally, the energy efficiency of the TARC roof and the effect of the phase transition temperature on the energy savings potential of the TARC roof are discussed in detail. The results showed that the TARC roof can address the issue of increased heating loads caused by passive daytime cooling (PDRC) roofs during the heating season. Furthermore, the annual total energy savings potential of the TARC roof is 6.3–23.5 MJ/m2 for buildings located in five different climatic zones in China. In addition, the annual energy savings of buildings with TARC roofs can be further improved by 3–7% once the optimal phase transition temperature is adopted.

ОБЕСПЕЧЕНИЕ ПОЖАРНОЙ БЕЗОПАСНОСТИ МНОГОЭТАЖНЫХ ЗДАНИЙ ИЗ ДЕРЕВЯННЫХ КОНСТРУКЦИЙ

Проведен обзор современного деревянного домостроения в России и за рубежом. Проанализированы результаты испытаний строительных материалов из древесины на пожарную опасность, а также деревянных строительных конструкций различных типов на огнестойкость и пожарную опасность как без огнезащиты, так и с огнезащитой различных видов. Разработаны предложения в нормативные документы. Намечены направления дополнительных исследований пожарной опасности зданий из деревянных конструкций. The paper considers the issues of ensuring fire safety of multi-storey buildings made of timber frame construction. At present, wooden houses in Russia are built mainly in the individual housing sector and account for 22% of the total construction volume, while industrial wooden houses account for no more than 3% of the wooden houses built annually. Abroad, wood is also widely used in the construction of buildings of various functional purposes: hotels, sports facilities, public and administrative buildings, low-rise and multi-storey buildings. The achievements of science, technology and engineering in the field of timber construction make it possible to design and build buildings of any type and purpose. Modern technology makes it possible to build high-rise timber houses. For example, high-strength composite materials based on wood are used for the construction of multi-storey buildings, in particular LVL beams and CLT panels. Numerous tests carried out at VNIIPO on load-bearing elements made of solid wood (frames, beams) and load-bearing structures made of CLT panels (walls, ceilings) have shown that they provide a significant limit of fire resistance in terms of load-bearing capacity. It is well known that wood is a highly flammable material (G4). This circumstance significantly complicates the use of various building structures in construction from the point of view of ensuring fire safety requirements, including in multi-storey buildings. A set of necessary engineering, technical and organisational measures to ensure fire safety has been developed for buildings with wooden structures up to 4 storeys. Based on the results of these tests, there have been developed proposals to include fire technical parameters in the regulatory requirements for buildings of classes I–III of fire resistance and structural fire hazard class C3. Further research is necessary to develop proposals for inclusion in the regulatory documents for fire safety of multi-storey residential and public buildings made of timber structures up to 28 metres in height.

Data-driven prediction of wind pressure on low-rise buildings in complex heterogeneous terrains

This study presents a data-driven methodology for predicting the pressure coefficient statistics on the windward wall, roof, and leeward wall of low-rise buildings situated downwind of complex heterogeneous terrains. Two types of artificial neural network models were developed: the empirical parameter-based ANN (PANN) and the morphology-based ANN (MANN). Pressure data from wind tunnel tests on the Wind Engineering Research Field Laboratory (WERFL) building model (building height H = 4 m) in complex heterogeneous terrain were used to develop the ANN models. These models were evaluated against a non-linear fitted model to assess their predictive performances. PANN and MANN demonstrated superior performance in capturing the effects of terrain complexity on the mean (Cp,mean) and the root-mean-square (Cp,RMS) wind pressure coefficients for the windward wall, roof, and leeward wall. Optimal prediction was achieved with a terrain patch size of W × L = 4 × 2, equating to a full-scale area of approximately 72 m × 23 m. This suggests that the morphology within approximately 100 m × 50 m (25H× 12.5H) in front of a low-rise building has the greatest correlation with the wind pressure coefficient. Despite lower R2 values for max Cp,RMS on the leeward wall across all models, both PANN and MANN showed promising accuracy for the six outputs studied. Moreover, a global sensitivity analysis confirmed the impact of terrain roughness and complexity on the prediction models particularly on max Cp,RMS, and underscored the dominance of effective roughness length z0,eff and the coefficient of variation of roughness length COVz0 in influencing model outcomes.

Characterization of tornado-induced wind pressures on a multi-span light steel industrial building

This study presents the characteristics of external wind pressures of a multi-span light steel industrial building through wind pressure measurements conducted in a tornado simulator. The test model is designed as a three-span low-rise building with gable roofs according to the practical measured sizes and shapes of the light steel industrial building destroyed in the Shengze tornado, China (2021). The distance from the tornado-like vortex center to the building, building orientation, roof angle, and swirl ratio are considered as experimental parameters. The effects of the parameters on the most unfavorable peak and mean pressure coefficients of each surface are analyzed. The roof zoning specified in ASCE 7–16 was re-analyzed based on the characteristics of wind pressure coefficients, and the tornado design pressure coefficients were calculated. The results of the analysis illustrate that the wind-ward roof surface at a distance of around one vortex core radius from the center experience the most severe pressure coefficient under tornado, the most unfavorable zone of the pressure coefficients on the building roof changes with the building orientation, the model with a smaller roof angle has smoother pressure coefficient contours than that with a larger roof angle because of the cutting effect of the ridge, and the simulated tornado with the lower swirl ratio generate higher external pressure coefficients on the building model. Moreover, the roof zoning in ASCE 7–16 for the boundary layer wind is not precise for tornado, thus an updated roof zoning for the tornado design pressure coefficients is defined.

Review of Wind Field Characteristics of Downbursts and Wind Effects on Structures under Their Action

Downbursts belong to sudden, local, and strong convection weather, which present significant destruction for structures. At any given time, there are approximately 2000 thunderstorms occurring on the Earth. Many studies have investigated the effects of downbursts on different structures. However, the extensive range of varying wind field parameters and the diverse representations of wind speeds render the study of structural wind effects complex and challenging under downbursts. This study firstly reviews the research of wind field properties of downbursts according to four common approaches, and the major findings, advantages, and disadvantages of which are concluded. Then, failure analysis of transmission line systems under stationary and moving downbursts is explored. The article also reviews the wind pressure on the roof of different kinds of low-rise buildings, and some dominant parameters, namely roof slope, distance of building from downburst center, wind direction angle, and so on, are discussed. Moreover, the wind effects caused by downbursts on high-rise buildings and some specialized structures are also considered because more and more wind hazards are related to downbursts. Finally, the limitations of the current study are pointed out, and recommendations for further research are given for the accurate assessment of the effects of wind on buildings, with a view to providing safer and more economical wind-resistant design solutions for structures.

Correlation analysis and joint probability density function model of wind pressures: Focusing on multivariate wind loads field on low-rise building under typhoon climate

The characteristics of the multivariate wind loads field on the roof are crucial to the wind-resistant design of low-rise buildings, which contain the correlation characteristics in space and probability characteristics in the time domain. This paper proposes a framework for constructing a Joint Probability Density Function (Joint PDF) model for a multivariate wind loads field. It provides a detailed correlation analysis for the first time. This paper employs wind pressure data collected from the roof of a low-rise building during Typhoon Muifa. It was found that the correlation becomes more robust with increasing roof pitch and the wind pressures are strongly correlated with a correlation coefficient exceeding 0.50 when the roof pitch is above 15°. The mixture distribution model is applied to the probability density function fitting procedure of wind pressure time series under typhoon climate, and the fitting effect is significantly better than other classical probability density functions. The optimal copula function is determined according to the Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC) for estimating the Joint PDF. The results reveal that Gumbel-copula and Student-copula have the highest proportion in optimal copula functions, accounting for over 90% of the total copula functions. Then, a bivariate Joint PDF for wind pressures are established with the optimal copula function. Additionally, the comparison between measured bivariate Joint PDF and that constructed using copula functions verifies the accuracy of the proposed framework for constructing Joint PDFs. The Joint PDF of wind pressures can enhance the understanding of the stochastic characteristics of local wind load fields on roofs, and the correlation characteristics in space provide crucial references for improving the accuracy of wind load random field simulation and saving the cost of wind resistance design.

Numerical Analysis of Spoilers and Chamfered Corners for Mitigating Wind Loads on Low-Rise Flat Roof Buildings

Numerical Analysis of Spoilers and Chamfered Corners for Mitigating Wind Loads on Low-Rise Flat Roof Buildings

Integration of Photovoltaic Systems for Energy Self-Sufficient Low-Rise Multi-Family Residential Buildings in Republic of Korea

Integration of Photovoltaic Systems for Energy Self-Sufficient Low-Rise Multi-Family Residential Buildings in Republic of Korea

Features of mechanization of work during the construction of buildings using low-rise construction technologies

Currently, in Uzbekistan, the low-rise housing construction sector is in a stage of dynamic development and, as a rule, is aimed at developing the territories of suburbs and agricultural areas. First of all, the trend of growth in the volume of low-rise residential construction is due to the fact that the construction of low-rise buildings is much less expensive in comparison with the construction of high-rise residential buildings. In addition, the operating costs of low-rise residential buildings are significantly lower than high-rise ones, since there is no need to install expensive engineering equipment (elevator equipment, high-power pumping equipment, fire protection systems, etc.). State programs in the field of providing the country's citizens with affordable and comfortable housing provide for a comprehensive reduction in its sales value, which is primarily achieved by reducing the cost of construction, including by reducing the consumption of fuel and energy resources (FER) during the construction of buildings.

Alternatives for Enhancing Mechanical Properties of Recycled Rubber Seismic Isolators.

Base isolators, traditionally made from natural rubber reinforced with steel sheets (SERIs), mitigate energy during seismic events, but their use in developing countries has been limited due to high cost and weight. To make them more accessible, lighter, cost-effective reinforcement fibers have been utilized. Additionally, the increasing use of natural rubber has caused waste storage and disposal issues, contributing to environmental pollution and disease spread. Exploring recycled rubber matrices as alternatives, this study improves seismic isolators' mechanical properties through modified reinforcements and layer adhesion. Eight reinforcement materials and eight adhesives, which may be activated with or without heat application, are systematically evaluated. Employing the chosen reinforcements and adhesives, prototypes are tested mechanically to examine their vertical and horizontal performance through cyclic compression and cyclic shear testing. Two innovative devices using recycled rubber matrices were developed, one using a layering technique and another through a monolithic approach shaped with heat and pressure. Both integrate a fiberglass mesh reinforced with epoxy resin; one employs a heat-activated hybrid adhesive, while the other uses a cold bonding adhesive. These prototypes exhibit potential in advancing seismic isolation technology for low-rise buildings in developing countries, highlighting the viability of recycled materials in critical structural applications.

A Case Study on the Seismic Evaluation of a Low-Rise Existing RC Building in Northeast India

A Case Study on the Seismic Evaluation of a Low-Rise Existing RC Building in Northeast India

Analysis of numerical simulations and semi-empirical models on distribution characteristics of wind-driven rain on low-rise building facades

Wind-driven rain (WDR) is a significant contributor to indoor moisture in buildings, directly impacting the thermal and moisture performance of facades. Previous research on WDR in China focused on a limited number of low-rise pilot buildings, whose materials, shapes, and environmental settings are not entirely representative of typical applications. Aim to improve the accuracy of WDR predictions on low-rise building facades, there is a need for assessing different WDR calculation methods under various rain events. The paper presented high-resolution WDR measurements from a low-rise concrete building in Chongqing to investigate the distribution of WDR on building facades under local meteorological conditions. The study compared the performance of numerical simulations and two semi-empirical models with different meteorological data averaging techniques. The results indicated that Computational Fluid Dynamics (CFD) simulations using the Eulerian multiphase (EM) model more closely matched the actual catch ratio across various locations and the WDR amount across the facade, with errors ranging between 10%-25 % and 2%–23 %, respectively. Furthermore, the ISO model with weighted averaging (WA) technique outperformed others in estimating catch ratios at various locations and the WDR amount across the facade, particularly when estimating the midline catch ratio. When considering both cumuliform and stratiform rainfall, the arithmetic averaging (AA) technique was a viable method for the ASHRAE model to forecast WDR. The ISO model's predictions corresponded to 54%–81 % of the field measurements, while the ASHRAE model's estimates varied more widely, ranging from 33 % to 229 % of the measured values.

Development and use of semi-empirical spectral ground motion models for GPP-induced micro-earthquakes in Southern Germany

This study provides a comprehensive exploration of ground motions associated with micro-earthquakes induced by geothermal power plants (GPP) in Southern Germany and proposes corresponding ground motion prediction equations (GMPE). Initiating with a statistical analysis of recorded seismic data from the GPP in Insheim, the study is extended to the greater Munich area. For the latter, the scarce recorded data are merged with physics-based simulation data. The recorded data in Insheim, Poing, Unterhaching and the simulated data in Munich are compared to existing GMPEs for GPP-induced events, highlighting the need of new region-specific prediction equations. The proposed GMPEs are expressed in terms of peak quantities, spectral accelerations and velocities, separating the horizontal and vertical direction. The regression curves exhibit a good alignment with both recorded and simulated data, within an acceptable range. Notably, the results reveal higher spectral quantities at shorter periods (<0.1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$<0.1$$\\end{document} s), underscoring the importance of this characteristic in seismic assessment. The article shows an exemplary application for a low-rise residential building, located at a hypocentral distance of 3 km. While the building meets serviceability standards for an MW\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$M_W$$\\end{document} up to 2.5, the verification fails at MW=3\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$M_W=3$$\\end{document}, emphasizing the need for robust risk assessment. These findings contribute to the understanding of ground motions of GPP-induced events, offering practical implications for serviceability verifications and aiding informed decision-making in geothermal energy projects.Graphical abstract

Enhancing LES efficacy in wind load evaluation of low-rise buildings using synthesized inflow turbulence

In Large-Eddy Simulation (LES), the turbulence inflow can be generated synthetically, where the input value of the maximum turbulence frequency can impact the accuracy. LES efficacy can be influenced by the designated computational domain (CD) size and grid specifications. This study proposes multiple parametric studies that aim to correlate the effective parameters controlling the accuracy of numerical wind load evaluation on a low-rise building without compromising the computational cost. The study includes the efficient selection of turbulence maximum frequency (fmax) that can accurately capture the pressure fluctuation induced on the building facade. Both CD size, which involves the distances from the building to the boundary condition, and CD discretization in terms of grid size scheme and shape, are examined. The error assessment is conducted by comparing wind flow aerodynamics and evaluating the RMSE for the pressure parameters with respect to the wind tunnel test. The findings of this study suggest using fmax which can be resolved by the minimum grid size as an input in the inflow turbulence generated to accurately transport the majority of eddies when a satisfactory wavelength of 4 Δx is utilized. This study shows that computational domain size and discretization can be significant sources of error that can reach 21 %, compromising the reliability of computational wind load predictions. The current code in selecting computational minimum width and length is found to be insufficient. In addition, it is found that there are currently no recommendations for selecting the width computational dimension specifications when examining low-rise buildings oriented in an oblique wind direction. The domain grid specification induced a considerable error of 14 % in the mean pressure across the roof when tetrahedral grid shapes were used. Overall, this study's proposed recommendations can significantly impact the efficacy of computational wind load evaluation for low-rise building geometry.

Damage to stone masonry buildings in historical centers due to the 2023 earthquake sequence in Turkey

Unreinforced stone masonry buildings represent a significant part of the building stock in the areas affected by the recent devastating earthquakes of 6 February 2023 in Turkey. Most of them were built before 2000, and, hence, they are not compliant with current seismic provisions. Severe damage or collapse was observed in a large number of low-rise stone masonry buildings, including many listed as monuments ones. The structural systems of masonry buildings in the historical center of two cities (namely, Gaziantep and Antakya) are presented herein, along with the typical damage observed. The causes of damage are qualitatively interpreted, wherever relevant evidence is available. To this purpose, the observed damage is compared to that occurred in other parts of the world, in structural systems similar to those of the area affected. Furthermore, the detrimental effect of inadequate pre-earthquake interventions is identified, while a critical discussion regarding frequently applied interventions, and the availability of design rules in current Codes and Guidelines, is initiated to pave the way toward efficient measures to be taken for the protection of surviving stone masonry buildings in Turkey and beyond.

Study on the contributions of 2D and 3D urban morphologies to the thermal environment under local climate zones

With the changes in global climate and rapid urbanization, identifying the contribution of urban morphology to the thermal environment under different scenarios could be helpful in proposing differentiated optimization responses of different scenarios for improving the thermal environment by means of natural cooling. This study calculated 2D and 3D metrics and retrieved surface temperature based on building vector data, land use, electronic map, the remote sensing images. Then, the study of spatial scale sensitivity was developed to build a nested multi-scale Local Climate Zone (LCZ) (NMSLCZ) map. Finally, the eXtreme Gradient Boost (XGBoost) regression model was performed to explore the relative contributions of 2D and 3D morphologies of different LCZ scenarios to surface temperatures. The results of scale sensitivity analysis showed the size of the optimal spatial scale decreased with the increase in building height. The 3D morphologies show more significant effects on LST variations than 2D morphologies. The surface temperature mainly by built type is significantly higher than that mainly by land cover type. Scenarios representing dense trees, shrubs, low vegetation, and water have significant cooling effects. In the scenarios of built types, the surface temperature of compact and large low-rise buildings is higher than that of the other building forms. Our findings provide a new perspective for LCZ mapping of scale optimization of the thermal environment. Meanwhile, the contributions of 2D and 3D morphologies on LSTs could help urban planners and managers understand the impacts of climate change and propose relevant strategies toward sustainable cities.

Cyclic behavior and pushover analysis of large scale two-bay, two-story reinforced concrete frames infilled with walls with openings

This study presents experimental results on the seismic behavior of a large-scale two-bay, two-story RC frame with RC infill walls, including openings typical of low-rise RC row buildings in Taiwan. The test findings indicated that the specimen failed due to the failure of the vertical members of the first story. Specifically, the critical wall segments located between openings and between an opening and a boundary column and short columns resulting from the presence of these openings were shown to be the main contributors to the failure. Based on the observed phenomenon during the test, an analytical model was verified and proposed for the tested specimen’s pushover analysis. The selection of plastic hinges in the analytical model was determined according to the Taiwan Earthquake Assessment for Structures by Pushover Analysis (TEASPA). Pushover analysis performed by commercially available software indicated that the analytical model could well capture the specimen's behavior regarding peak base shear, initial stiffness, displacement of each story, and development of plastic hinges.

Building Mass Optimization to Reduce Solar Radiation in High Rise Building by Using Parametric Approach

Buildings use 40% of global primary energy, therefore their design and use affect climate change. Building performance analysis can assist architects predict performance before construction with parametric design tools. Radiance can be reduced via a parametric mass, lowering cooling load and energy use. The study uses theoretical and computational research to explain, forecast, and analyze events, whereas parametric design optimizes complicated geometries using mathematical parameters and algorithms. Environmental analysis in Grasshopper with the Ladybug plugin uses Rhinoceros. This plugin provides solar radiation, and climate analysis capabilities. To determine the most energy-efficient building design, the research links independent and dependent variables such solar radiation intensity and building mass. The study uses Surabaya weather data and high rise buildings. The land is formed like a square, with a 15-degree slope to the north and is flanked by low-rise buildings. As a result, the location receives the most direct sunlight during the day. Then, solar radiation analysis. It helps optimize passive solar design solutions. According to the modelling results, solar radiation on the top and west sides are particularly large and dominant in 65.37 and 32.69 kWh/m2. Meanwhile, the north, east and south sides receive very little solar radiation. The following simulation considers the optimal direction, which is to extend west-east and face to the south. A multi-towered megastructure is a high-rise building that responds best to solar radiation. The total solar radiation value is 3,718,100 kWh. It can accommodate large spaces with large mass composition but relatively low total solar radiation values. The building towers provide shade to each other, thereby reducing direct radiation from the sun to the building. The sides of the building's podium are also shaded, so the top of the building is partially red.

Integrating vertical greenery for complex building patterns towards sustainable urban environment

Rapid urbanization has increased the urban density and functional diversity, exacerbating environmental challenges such as urban heat islands (UHI), increased building energy consumption and carbon emissions, etc., hindering the sustainable urban development. Addressing these challenges requires innovative solutions that could offer the strategic cooling of urban buildings. Vertical greenery, affixed to building façades, offers a promising approach to provide benefits of cooling, energy savings, carbon reduction and urban space saving. However, there is a lack of quantitative design for integrating vertical greenery into complex urban buildings. Therefore, this study conducts a systematic investigation for low-rise, mid-rise, and high-rise buildings incorporating vertical greenery, while performing comprehensive assessments on indoor and outdoor thermal conditions, building energy usage, and carbon emissions. The findings suggest that low-rise buildings benefit from a vertical greenery layout, while mid-rise and high-rise buildings are better suited for a horizontal greenery layout. Compared to scenarios without greenery, buildings with vertical greenery experience a maximum reduction of 0.66 °C in outdoor air temperature and 0.72 °C in indoor air temperature, along with a 5.9 % decrease in energy consumption and carbon emissions. This study addresses urban challenges through a quantified vertical greenery design, offering valuable insights for sustainable urban development.