Narrow Results

Buildings with reinforced concrete (RC) integrate steel reinforcement with concrete to increase the structure’s durability and load-bearing capability. A significant issue is the corrosion of the steel reinforcement, especially in high-humidity environments or when exposed to deicing salts. This paper proposes a novel technique for predicting the fundamental period (FP) of RC buildings considering infill walls and soil–structure interaction (SSI) effects. The proposed technique is the multi-component attention graph convolutional neural network (MCAGCNN). The primary objective of the proposed method is to achieve high prediction accuracy and minimal error in approximating the FP of RC frame-building models, thereby improving the reliability of structural analysis and design. Initially, data are collected from Housing Database Project Level Files. This study primarily investigated three types of buildings: Bare frames, buildings with fully unfilled walls, and buildings with an open first floor. The research considered the effects of various factors like infill stiffness, number of bays, SSI, bay width, and the FP of the buildings. The concrete grade, the number of stories, the building’s width and length, and the number of bays are the input parameters used to predict the FP. The FP of RC buildings with and without SSI effects is predicted using the proposed MCAGCNN technique. The proposed MCAGCNN approach improves accuracy by 19.36%, 26.42%, and 23.27%, increases precision by 22.36%, 15.42%, and 18.27%, and reduces RMSE by 18.36%, 16.42%, and 28.27%, compared to the existing techniques, including Genetic Algorithms (GA), Gradient Boosting Decision Trees (GBDT), and Artificial Neural Networks (ANN). The proposed study also demonstrates a lower $L\infty$ norm error of 0.045, indicating a high degree of accuracy and minimal deviation between predicted and actual values.

Passive radiative cooling (PRC)-based smart windows are emerging as a potential solution for reducing the energy needs of buildings, both homes and offices alike. While a lot of research has occurred in this regard, vanadium oxide-based materials are studied very recently. We carry out a finite element method-based simulation study to understand the behavior of using vanadium pentoxide (V₂O₅) as a coating on glass windows. The proposed design can help in saving energy by emitting cooler rays inside the building when direct sun rays fall on the coated glass surface, thereby reducing internal room temperatures. It is also a solution to global warming, as the emissions from ACs will reduce due to the lower inside temperature of buildings thereby reducing demand on power usage. We found that the ambient temperature ($T_{\mathrm{\text{amb}}}$) inside buildings can be reduced by up to $8^{\circ }C$ when the outer temperature is $40^{\circ }C$. Also, the surface radiosity of V₂O₅ windows is twice that of glass windows and increases with the outer temperature. Lastly, we compare the performance of V₂O₅ with that of VO₂ and find that they have similar characteristics of radiant exitance, surface radiosity and surface emissivity of long-wave infrared (LWIR) rays thus making V₂O₅ as a possible candidate for PRC which is low cost and affordable to many people.

The looming climate emergency coupled with the present-day energy crisis has led to an urgent need to decarbonize the building stock for a clean energy transition. However, the sector is not at pace with the Paris Agreement goals and requires deep systematic changes to achieve the 2050 net-zero targets. This paper presents energy sufficiency as an approach to accelerate building decarbonization that goes beyond energy efficient and renewable energy technologies and leverages lifestyle choices and practices to achieve the targeted climate goals. We synthesize the existing knowledge on sufficiency in the buildings domain encompassing empirical studies, estimating up to 48% energy savings and 54% GHG emissions reduction potential of sufficiency actions, and the possible approaches for implementation to develop a comprehensive understanding of sufficiency potential in the building sector. We also present different categories of sufficiency measures and identify the related policy and technological innovations required to implement them. Lastly, we discuss the opportunities for sufficiency-oriented building decarbonization within the national policies and roadmaps. This review intends to provide insights into the development of sufficiency-oriented strategies and policies for enabling a just energy transition in the building sector.

The terrorist explosion is dreadful for current world. In various explosive events, vehicle bomb explosion has been commonly used by terrorists to approach the targets. This paper evaluated and analyzed the minatory grades of various vehicle bombs, and calculated the failure distances of the buildings under the main impulse effect of air shock wave. Thereafter, a few kinds of setting methods of the blast resistant walls under various vehicle bombs are established. The research will provide effect protective measures for the survival ability of the important buildings under various vehicle bombs.

Let A be a symmetrizable affine or hyperbolic generalized Cartan matrix. Let G be a locally compact Kac–Moody group associated to A over a finite field 𝔽_q. We suppose that G has type ∞, that is, the Weyl group W of G is a free product of ℤ/2ℤ's. This includes all locally compact Kac–Moody groups of rank 2 and three possible locally compact rank 3 Kac–Moody groups of noncompact hyperbolic type. For every prime power q, we give a sufficient condition for the rank 2 Kac–Moody group G to contain a cocompact lattice with quotient a simplex, and we show that this condition is satisfied when q = 2^s. If further M_q and are abelian, we give a method for constructing an infinite descending chain of cocompact lattices … Γ₃ ≤ Γ₂ ≤ Γ₁ ≤ Γ. This allows us to characterize each of the quotient graphs of groups Γ_i\\X, the presentations of the Γ_i and their covolumes, where X is the Tits building of G, a homogeneous tree. Our approach is to extend coverings of edge-indexed graphs to covering morphisms of graphs of groups with abelian groupings. This method is not specific to cocompact lattices in Kac–Moody groups and may be used to produce chains of subgroups acting on trees in a general setting. It follows that the lattices constructed in the rank 2 Kac–Moody group have the Haagerup property. When q = 2 and rank(G) = 3 we show that G contains a cocompact lattice Γ′₁ that acts discretely and cocompactly on a simplicial tree . The tree is naturally embedded in the Tits building X of G, a rank 3 hyperbolic building. Moreover Γ′₁ ≤ Λ′ for a non-discrete subgroup Λ′ ≤ G whose quotient Λ′ \ X is equal to G\X. Using the action of Γ′₁ on we construct an infinite descending chain of cocompact lattices …Γ′₃ ≤ Γ′₂ ≤ Γ′₁ in G. We also determine the quotient graphs of groups , the presentations of the Γ′_i and their covolumes.

This paper evaluates a recently developed hybrid method for the embodied energy analysis of the Australian construction industry. It was found that the truncation associated with process analysis can be up to 80%, whilst the use of input-output analysis alone does not always provide a perfect model for replacing process data. There is also a considerable lack in the quantity and possibly quality of process data currently available. These findings suggest that current best-practice methods are sufficiently accurate for most typical applications, but this is heavily dependant upon data quality and availability. The hybrid method evaluated can be used for the optimisation of embodied energy and for identifying opportunities for improvements in energy efficiency.

When reinforced-concrete columns are subjected to lateral cyclic loading, columns usually suffer failures at plastic hinges. If the buckling of longitudinal reinforcements at plastic hinges can be prevented or delayed, columns are expected to carry gravity loads at a higher ductility level. In this study, the rebar-restraining collar (RRC) was developed to improve the post-buckling behavior of longitudinal reinforcements. The behavior was investigated under monotonic loading tests of reinforcing bars with the RRCs and the cyclic loading tests of two reinforced-concrete bridge columns with and without RRCs. From the monotonic loading test, it was found that the RRCs significantly improved the post-yielding behavior of longitudinal reinforcing bars. The ductility and energy dissipation of longitudinal reinforcing bars with RRCs was significantly higher than that of the bare bar. Then, cyclic loading tests of two reinforced-concrete bridge columns were conducted. The cross section of columns was 0.4 m × 0.4 m, and the effective height was 2.15 m. The ratio of longitudinal reinforcing bars was 0.0123, and the volumetric ratio of transverse reinforcement was 0.00424. The column with RRCs did not have buckling of longitudinal reinforcements and had the ductility enhancement of about 17%, comparing to the column without RRCs. One evident benefit of using the RRCs is to control damage at plastic hinges of columns. Hence, the repair cost of columns after an earthquake can be reduced.

Seventy million American homes and businesses burn natural gas, oil, or propane on-site to heat their space and water, generating 560 million tons of carbon dioxide each year — one-tenth of total US emissions. But now, we have the opportunity to meet nearly all our buildings’ energy needs with electricity from an increasingly low-carbon electric grid, eliminating direct fossil fuel use in buildings and making obsolete much of the gas distribution system — along with its costs and safety challenges…