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On the anniversary of Haiti's devastating quake, Nicholas Ambraseys and Roger Bilham calculate that 83% of all deaths from building collapse in earthquakes over the past 30 years occurred in countries that are anomalously corrupt.

Relationships in ACI 318-14 for calculating the concrete contribution to shear resistance ([V.sub.c]) in reinforced concrete (RC) members (that is, non-prestressed) have been replaced in ACI 318-19 by one general relationship that considers the combined effects of member depth, percentage of longitudinal reinforcement, and the effect of axial stress on predicted shear strength capacity. This new relationship is [V.sub.c] = [(8[[lambda].sub.s][lambda][[[rho].sub.w]].sup.1/3][square root][f'.sub.c] + [N.sub.u]/[6[A.sub.,g]])[b.sub.w]d, where [[lambda].sub.s] is a size effect factor equal to [square root] (2/[1 + d/10])] that accounts for a reduction in shear stress capacity with increasing member depth. The frequently used expression in ACI 318-14, [V.sub.c] = 2[lambda][square root][f.sub.c'bwd], may continue to be used in members containing at least the minimum level of shear reinforcement. The one-way shear provisions for prestressed concrete (PC) members were not changed in this code cycle. The primary basis for the new RC provisions are test results compiled in databases developed and analyzed over the past two decades through a collaboration of Joint ACI-ASCE Committee 445, Shear and Torsion, and the German Committee for Structural Concrete (DAbStb). The process for developing these new provisions included an invitation to the ACI community to suggest new one-way shear design provisions. These suggestions were discussed within Joint ACI-ASCE Committee 445, and then evaluated and modified by ACI Subcommittee 318-E, Section and Member Strength, with consideration of their basis, accuracy, safety, ease-of-use, and range of application. Keywords: building code; database; design; experiments; shear.

Extreme heat and cold brought on by climate change put people at risk. Beefing up building codes now could help to save lives. Extreme heat and cold brought on by climate change put people at risk. Beefing up building codes now could help to save lives. Credit: Andrea Starr/PNNL Meredydd Evans.

The escalating environmental threat of indoor overheating, exacerbated by global climate change, urbanisation, and population growth, poses a severe risk to public health worldwide, specifically to those regions which are exposed to extreme heat events, such as Australia. This study delves into the critical issue of overheating within residential buildings, examining the existing state of knowledge on overheating criteria and reviewing overheating guidelines embedded in (a) international standards and (b) national building codes. Each regulatory document is analysed based on its underlying thermal comfort model, metric, and indices. The advantages and limitations of each document are practically discussed and for each legislative document and standard, and the quantitative measures have been reviewed, analysed, and summarised. The findings illuminate a global reliance on simplistic indices, such as indoor air temperature and operative temperature, in the existing regulatory documents. However, other critical environmental parameters, such as relative humidity, indoor air velocity, and physiological parameters including metabolic heat production and clothing insulation, are often not included. The absence of mandatory regulations for overheating criteria in residential buildings in some countries, such as in Australian homes, prompts the call for a holistic approach based on a thermal index inclusive of relevant environmental and physiological parameters to quantify heat stress exposure based on human thermal regulation. Gaps and limitations within existing guidelines are identified, and recommendations are proposed to strengthen the regulatory framework for overheating risk assessment in residential buildings. The findings hold significance for policymakers, building energy assessors, architects, and public health professionals, providing direction for the improvement of existing, and development of new, guidelines that aim to enhance indoor thermal condition and population health while ensuring energy efficiency and sustainability in the building stock.

Despite the intensity of the 2018 Camp Fire, many structures survived in heavily burned areas. Logistic regressions were run to determine which structural and parcel characteristics predicted structure survival using two data sets. The first, CAL FIRE’s Damage Inspections (DINS) dataset, included 14 518 destroyed and 622 partially damaged structures. The second, combining information from the DINS and Defensible Space (DINS+DSPACE) databases, had many more attributes and was better balanced between destroyed (n = 728) and surviving (n = 676) structures, but was much smaller. Several approaches were compared for filtering out records with null values. Results were largely consistent with previously literature, finding that structural hardness factors (e.g. double-paned windows, enclosed eaves, ignition-resistant roofs and siding, no vents, etc.) are important in determining structure survival. Newer structures, built after California’s recent (2005 and 2007) fire safe building code updates, were more likely to survive, as were homes with higher improvement values. Mobile homes were far more likely to be destroyed. The role of fuel mitigation around structures was less conclusive; defensible space clearance had only a weak association with structure survival, although DINS+DSPACE results suggested a slight reduction in risk due to removing leaves and needles from gutters/roofs and keeping surrounding dead grass mowed.

This study explores the application of Close-Range Photogrammetry (CRP) for the structural assessment and compliance evaluation of stairs at the UP Diliman Institute of Civil Engineering. The analysis was performed on multiple flights of stairs, where scaling was done using a reference object due to the absence of ground control points (GCPs). For each step, three measurements were taken for both tread and rise dimensions and the average was computed to represent the values for consistency. Additionally, the standard deviation (SD) for both tread and rise within each flight was calculated to assess variability and conformity to the National Building Code of the Philippines (NBCP) standards. The results revealed significant variability in both tread and rise dimensions across the stairs. Only two flights of stairs out of twelve satisfied the 5 mm SD limit for tread, while none for rise. Ninety-three point sixteen percent (93.16%) fell outside the recommended tread range of 250-280 mm. The largest observed SDs were 11.16 mm for tread and 19.41 mm for rise, indicating considerable inconsistency in the stair dimensions. In terms of accuracy, the study validated the CRP method by comparing photogrammetry with actual physical measurements of the stairs. The Root Mean Square Error (RMSE) and Margin of Error (MOE) were used, yielding favorable results. The first stair demonstrated high accuracy, while the second showed minor variations that still fell within the lower end of the observed range, highlighting the reliability and precision of the measurement methods employed.

Civil structures are prone to dynamic loadings such as strong winds or ground excitations where torsion becomes an ongoing issue. This arises from a lack of coincidence of the center of mass (CM) and rigidity (CR), known as eccentricity. Seismic design codes often introduce two types of eccentricity: inherent (geometric) and accidental. To account for structural or ground motion uncertainties, an assumption-based solution is provided by many code provisions, which considers the accidental eccentricity as a percentage (5% or 10%) of the building length perpendicular to the direction of exposed ground motion. In this study, as an alternative way to the code design parameters, a new design eccentricity formula that considers the frequency ratio (torsional frequency/translation frequency) and an effective radius of gyration to account for torsional irregularity is considered. For the extended validation of the proposed method, eighteen model buildings with six different floor plans were chosen, representing low, medium-height, and high-rise buildings. Each floor plan had model buildings with three, seven, and twelve stories. The buildings were subjected to selected bidirectional earthquake ground motions and had time history analyses performed. The results of the proposed method were compared to code provision methods, obtained using equivalent lateral force procedures, and also to those obtained utilizing the time history analysis results. It was shown that the proposed method was more effective in estimating the impact of torsional eccentricity and provided a better understanding of its impact on structural dynamic characteristics.

The transition from the Uniform Building Code (UBC-97) to the International Building Code (IBC-21) marked a major shift in the definition of seismic hazard. The term “seismic hazard” in the form of peak ground acceleration (PGA) is replaced by spectral acceleration. This paper investigates the effect of using new seismic hazards on the structural performance of reinforced concrete (RC) buildings. It also looks into the financial impact on the capital costs of new buildings. Useful insights are made to understand the structural performance and financial impact of adopting IBC 21 for structural design in contrast to UBC 97. This study was carried out from the perspective of a developing country, Pakistan. Reinforced concrete moment resisting and dual frames are used as the main structural system of a typical 7-story residential building to investigate the aforementioned effect. The frames are assumed to be located in two locations with high and low seismic hazards. The effect on structural performance is investigated via nonlinear pushover analysis. Financial impact is judged mainly through cost estimation for steel and concrete. A detailed discussion is also presented on the seismic design guidelines in both codes.

The first edition of ACT CODE-440.11 was published in September 2022, where some code provisions were either based on limited research or only analytically developed. Therefore, some code provisions, notably shear and development length in footings, are difficult to implement. This study, through a design example, aims at a better understanding of the implications of code provisions in ACT CODE-440.11-22 and compares them with ones in CSA S806-12, thereby highlighting a need for reconsiderations. An example of the footing originally designed with steel reinforcement was taken from the ACI Reinforced Concrete Design Handbook and redesigned with GFRP reinforcement as per ACT CODE-440.11-22 and CSA S806-12. A footing designed as per ACI CODE-440.11-22 requires a thicker concrete cross section to satisfy shear requirements; however, when designed as per CSA S806-12, the required thickness becomes closer to that of the steel-reinforced concrete (RC) footing. The development length required for a glass fiber-reinforced polymer-reinforced concrete (GFRP-RC) cross section designed as per ACI CODE-440.11-22 was 13% and 92% greater than that designed as per CSA S806-12 and ACI 318-19, respectively. Also, the reinforcement area required to meet detailing requirements is 170% higher than that for steel-RC cross section. Based on the outcomes of this study, there appears to be a need for reconsideration of some code provisions in ACI CODE-440.11-22 to make GFRP reinforcement a viable option for RC members.

The built environment in Saudi Arabia accounts for approximately 78% of the country’s total electricity consumption, positioning building energy performance as one of the most consequential levers available to policymakers pursuing the kingdom’s net-zero greenhouse gas emissions target for 2060 and Vision 2030’s sustainability agenda. Despite the progressive introduction of the Saudi Building Code (SBC) energy chapters SBC 601, SBC 602, and the Saudi Green Building Code (SgBC 1001), a persistent gap remains between regulatory intent and measurable outcomes across Saudi Arabia’s five distinct climatic zones. Building codes are, by design, generic policy instruments encompassing structural, fire, accessibility, and energy provisions; this paper focuses specifically on the energy and sustainability dimensions and critically examines how the SBC’s update cycle and prescriptive compliance architecture shape actual performance outcomes. This study presents three explicit research questions: (RQ1) What zone-differentiated energy savings does SBC implementation deliver across residential typologies? (RQ2) How does the Mostadam national rating system compare with international benchmarks in the Saudi context, and what caveats govern that comparison? (RQ3) What evidence-based policy interventions are needed to transition from compliance-led to performance-led building energy governance? Drawing on a systematic synthesis of 53 building energy simulation models (2018–2025), official programme data, and a structured comparative analysis of Mostadam against LEED v4.1 and BREEAM, the study finds EUI reductions of 5–25% from SBC compliance, with the largest savings in the hot–humid coastal zone. Seven prioritised policy recommendations are proposed, addressing code revision, financial incentives, digital monitoring, renewable energy thresholds, and capacity building.