Hussam Mahmoud

Bio: Hussam Mahmoud is an academic researcher from Colorado State University. The author has contributed to research in topics: Community resilience & Finite element method. The author has an hindex of 20, co-authored 144 publications receiving 1283 citations. Previous affiliations of Hussam Mahmoud include Lehigh University & University of Minnesota.

Implementing BIM on Infrastructure: Comparison of Two Bridge Construction Projects

Abstract: This research provides comparative analysis of the impacts and benefits associated with using building information modeling (BIM) on accelerated bridge construction in the Denver metropolitan area. To date, BIM remains a relatively underutilized tool in horizontal construction. BIM has the potential, however, to significantly increase efficiencies, minimize waste, and increase sustainability across infrastructure projects throughout their life cycles. This research studies the impacts of the first implementation of BIM processes on one of two structurally similar concurrent bridge construction projects by comparing metrics related to substructure costs, requests for information, change orders, rework, and schedule. Findings suggest that negative cost impacts of approximately 70% may be associated with the first implementation of BIM during construction. However, additional findings suggest that the use of BIM may facilitate otherwise infeasible complex projects and reduce requests for information ...

New Model for Ductile Fracture of Metal Alloys. I: Monotonic Loading

Abstract: In the absence of geometrical constraints, ductile fracture has been identified as the predominant mode of failure for structural elements under extreme loads, the prediction of which still represents considerable challenges. Ductile fracture of metals has only recently been recognized to be dependent on both stress triaxiality and Lode angle parameter. In this study, a new fracture model that is dependent on both stress triaxiality and Lode parameter is proposed. The developed model is proposed for the case of monotonic loading and is applicable to a wide range of stress states. The extension of the model to reverse loading, with complex loading history, is addressed in a parallel paper. The developed criterion is evaluated against data extracted from a series of multistress states monotonic experimental results for various metals, and a strong correlation is evident between the proposed model and experimental results in the entire range of the tested stress states. A detailed parametric study is...

Inspection and Management of Bridges with Fracture-Critical Details

Abstract: This synthesis may be useful to bridge owners and consulting engineers engaged in the design, inspection, and management of bridges with fracture-critical details, as a guide to present specifications and engineering judgment. It focuses on the inspection and maintenance of bridges with fracture-critical members (FCMs), as defined in the AASHTO "LRFD Bridge Design Specifications." The objectives of this report were to survey and identify gaps in the literature; determine practices and problems with how bridge owners define, identify, document, inspect, and manage bridges with fracture-critical details; and identify specific research needs. Among the areas examined were: inspection frequencies and procedures; methods for calculating remaining fatigue life; qualification, availability, and training of inspectors; cost of inspection programs; instances where inspection programs prevented failures; retrofit techniques; fabrication methods and inspections; and experience with FCM fractures and problems details. This synthesis contains information obtained from a survey distributed to bridge owners and consultant inspectors (72 state, provincial, and international departments of transportation and agencies), a literature search, and targeted interviews. Useful responses were received from 34 states and three Canadian provinces.

The Role of Urban Growth in Resilience of Communities Under Flood Risk

Abstract: Flood risk to urban communities is increasing significantly as a result of the integrated effects of climate change and socioeconomic development. The latter effect is one of the main drivers of rising flood risk has received less attention in comparison to climate change. Economic development and population growth are major causes of urban expansion in flood-prone areas, and a comprehensive understanding of the impact of urban growth on flood risk is an essential ingredient of effective flood risk management. At the same time, planning for community resilience has become a national and worldwide imperative in recent years. Enhancements to community resilience require well-integrated and enormous long-term public and private investments. Accordingly, comprehensive urban growth plans should take rising flood risk into account to ensure future resilient communities through careful collaboration between engineers, geologists, socialists, economists, and urban planners within the framework of life-cycle analysis. This paper highlights the importance of including urban growth in accurate future flood risk assessment and how planning for future urbanization should include measurement science-based strategies in developing policies to achieve more resilient communities.

Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study

Abstract: Summary Background Since December, 2019, Wuhan, China, has experienced an outbreak of coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Epidemiological and clinical characteristics of patients with COVID-19 have been reported but risk factors for mortality and a detailed clinical course of illness, including viral shedding, have not been well described. Methods In this retrospective, multicentre cohort study, we included all adult inpatients (≥18 years old) with laboratory-confirmed COVID-19 from Jinyintan Hospital and Wuhan Pulmonary Hospital (Wuhan, China) who had been discharged or had died by Jan 31, 2020. Demographic, clinical, treatment, and laboratory data, including serial samples for viral RNA detection, were extracted from electronic medical records and compared between survivors and non-survivors. We used univariable and multivariable logistic regression methods to explore the risk factors associated with in-hospital death. Findings 191 patients (135 from Jinyintan Hospital and 56 from Wuhan Pulmonary Hospital) were included in this study, of whom 137 were discharged and 54 died in hospital. 91 (48%) patients had a comorbidity, with hypertension being the most common (58 [30%] patients), followed by diabetes (36 [19%] patients) and coronary heart disease (15 [8%] patients). Multivariable regression showed increasing odds of in-hospital death associated with older age (odds ratio 1·10, 95% CI 1·03–1·17, per year increase; p=0·0043), higher Sequential Organ Failure Assessment (SOFA) score (5·65, 2·61–12·23; p Interpretation The potential risk factors of older age, high SOFA score, and d-dimer greater than 1 μg/mL could help clinicians to identify patients with poor prognosis at an early stage. Prolonged viral shedding provides the rationale for a strategy of isolation of infected patients and optimal antiviral interventions in the future. Funding Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences; National Science Grant for Distinguished Young Scholars; National Key Research and Development Program of China; The Beijing Science and Technology Project; and Major Projects of National Science and Technology on New Drug Creation and Development.

Minimum Design Loads for Buildings and Other Structures

Abstract: Minimum Design Loads for Buildings and Other Structures provides requirements for general structural design and includes means for determining dead, live, soil, flood, wind, snow, rain, atmospheric ice, and earthquake loads, as well as their combinations, which are suitable for inclusion in building codes and other documents. This Standard, a revision of ASCE/SEI 7-05, offers a complete update and reorganization of the wind load provisions, expanding them from one chapter into six. The Standard contains new ultimate event wind maps with corresponding reductions in load factors, so that the loads are not affected, and updates the seismic loads with new risk-targeted seismic maps. The snow, live, and atmospheric icing provisions are updated as well. In addition, the Standard includes a detailed Commentary with explanatory and supplementary information designed to assist building code committees and regulatory authorities. Standard ASCE/SEI 7 is an integral part of building codes in the United States. Many of the load provisions are substantially adopted by reference in the International Building Code and the NFPA 5000 Building Construction and Safety Code. Structural engineers, architects, and those engaged in preparing and administering local building codes will find this Standard an essential reference in their practice. Note: New orders are fulfilled from the second printing, which incorporates the errata to the first printing.

Climate-induced variations in global wildfire danger from 1979-2013

Abstract: Climate strongly influences global wildfire activity, and recent wildfire surges may signal fire weather-induced pyrogeographic shifts. Here we use three daily global climate data sets and three fire danger indices to develop a simple annual metric of fire weather season length, and map spatio-temporal trends from 1979 to 2013. We show that fire weather seasons have lengthened across 29.6 million km2 (25.3%) of the Earth's vegetated surface, resulting in an 18.7% increase in global mean fire weather season length. We also show a doubling (108.1% increase) of global burnable area affected by long fire weather seasons (>1.0 σ above the historical mean) and an increased global frequency of long fire weather seasons across 62.4 million km2 (53.4%) during the second half of the study period. If these fire weather changes are coupled with ignition sources and available fuel, they could markedly impact global ecosystems, societies, economies and climate.

Fangcang shelter hospitals: a novel concept for responding to public health emergencies

Abstract: Fangcang shelter hospitals are a novel public health concept. They were implemented for the first time in China in February, 2020, to tackle the coronavirus disease 2019 (COVID-19) outbreak. The Fangcang shelter hospitals in China were large-scale, temporary hospitals, rapidly built by converting existing public venues, such as stadiums and exhibition centres, into health-care facilities. They served to isolate patients with mild to moderate COVID-19 from their families and communities, while providing medical care, disease monitoring, food, shelter, and social activities. We document the development of Fangcang shelter hospitals during the COVID-19 outbreak in China and explain their three key characteristics (rapid construction, massive scale, and low cost) and five essential functions (isolation, triage, basic medical care, frequent monitoring and rapid referral, and essential living and social engagement). Fangcang shelter hospitals could be powerful components of national responses to the COVID-19 pandemic, as well as future epidemics and public health emergencies.