Architectural Engineering Commons^™

Regularized Inversion Of Aerosol Hygroscopic Growth Factor Probability Density Function: Application To Humidity-Controlled Fast Integrated Mobility Spectrometer Measurements, Jiaoshi Zhang, Yang Wang, Steven Spielman, Susanne Hering, Jian Wang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Aerosol hygroscopic growth plays an important role in atmospheric particle chemistry and the effects of aerosol on radiation and hence climate. The hygroscopic growth is often characterized by a growth factor probability density function (GF-PDF), where the growth factor is defined as the ratio of the particle size at a specified relative humidity to its dry size. Parametric, least-squares methods are the most widely used algorithms for inverting the GF-PDF from measurements of the humidified tandem differential mobility analyzer (HTDMA) and have been recently applied to the GF-PDF inversion from measurements of the humidity-controlled fast integrated mobility spectrometer (HFIMS). However, …

Neuromorphic Computing Using Electrostatic Mems Devices, Fadi Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

A continuous - time recurrent neural network ( CTRNN ) is described that exploits the nonlinear dynamics of micro electro - mechanical system ( MEMS ) devices to model a neuron in accordance with a neuron rate model that is the basis for dynamic field theory . Each MEMS device in the CTRNN is configured to simulate a neuron population by exploiting the characteristics of bi - stability and hysteresis inherent in certain MEMS device structures . In an embodiment , the MEMS device is a microbeam or cantilevered microbeam device that is excited with an alternating current ( AC …

History And Technique In Reinforce Concrete Formworks: A Study Of Pier Luigi Nervi Approach, Moritz Meditz

Symposium of Student Scholars

The last hundred years in architecture and civil engineering have been widely dominated by the use of concrete, which became the second most consumed commodity after water. The traditional use of rigid, flat formwork panels has defined reinforced concrete members as a uniform cross-section, prismatic structural elements in both design codes and construction methods. These resultant shapes have become practically an inevitable conclusion for concrete constructions. This presentation focuses on alternative formwork construction looking at the work of engineer, architect and builder, Pier Luigi Nervi (1891–1979). Nervi was an adjunct professor at the University of Rome and a prolific writer, …

Feasibility Study Of Implementing Gamma-Ray Computed Tomography On Measuring Aggregate Distribution And Radiation Shielding Properties Of Concrete Samples, Omar Farid, Nima Farzadnia, Kamal Khayat, Muthanna H. Al-Dahhan

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Aggregate segregation is one of the key defects that impair the performance of concrete at fresh and hardened stages. This study aims to assess the feasibility of using an advanced technique to identify/scan/determine the aggregate segregation of concrete elements and determine radiation shielding properties of the concrete. The gamma-ray computed tomography (γ-CT) technique was employed to study aggregate distribution/dispersion in self-consolidating concrete (SCC). Accordingly, two SCC mixtures with moderate segregation (MS) and high segregation (HS) levels were cast and compared with highly stable SCC with no segregation (NS). The γ-CT scans were located on three different levels of concrete specimens …

Fast Forest Fire Smoke Detection Using Mvmnet, Yaowen Hu, Jialei Zhan, Guoxiong Zhou, Aibin Chen, Weiwei Cai, Kun Guo, Yahui Hu, Liujun Li

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Forest Fires Are a Huge Ecological Hazard, and Smoke is an Early Characteristic of Forest Fires. Smoke is Present Only in a Tiny Region in Images that Are Captured in the Early Stages of Smoke Occurrence or When the Smoke is Far from the Camera. Furthermore, Smoke Dispersal is Uneven, and the Background Environment is Complicated and Changing, Thereby Leading to Inconspicuous Pixel-Based Features that Complicate Smoke Detection. in This Paper, We Propose a Detection Method Called Multioriented Detection based on a Value Conversion-Attention Mechanism Module and Mixed-NMS (MVMNet). First, a Multioriented Detection Method is Proposed. in Contrast to Traditional …

Quantitative Evaluation Of Steel Corrosion Induced Deterioration In Rubber Concrete By Integrating Ultrasonic Testing, Machine Learning And Mesoscale Simulation, Jinrui Zhang, Mengxi Zhang, Biqin Dong, Hongyan Ma

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Chloride-induced steel corrosion seriously affects the durability of reinforced concrete structures. Rubber concrete, an environmentally friendly construction material in which waste rubber is recycled as a concrete component, has demonstrated superior resistance to chloride-induced steel corrosion and the subsequent concrete deterioration. However, quantitative evaluation of the degree of deterioration in rubber concrete based on nondestructive detection is challenging due to the complexity of the material. In this paper, reinforced concrete specimens with rubber contents of 0, 10% and 20% are subjected to the electrochemically accelerated corrosion experiments and monitored by ultrasonic testing. Six machine learning models are trained by the …

Exploring The Use Of Re-Forming Concrete, Moritz Meditz

Bachelor of Architecture Theses - 5th Year

This thesis takes a closer look at concrete construction in the modern area and, more specifically, the use of formwork to shape the built environment.

Traditional rigid concrete formwork has been optimized for buildability while serving structural needs. This mentality means simple prismatic elements that are entirely overbuilt for the task, stacked on top or next to one another. The idea that these elements are the peak of efficiency in concrete production has informed virtually all modern concrete construction. Any shapes that vary from the simple prismatic volumes are seen as challenging to build and expensive. For the most part, …

Development And Characterization Of Magnesium Phosphate Cement Based Ultra-High Performance Concrete, Jihui Qin, Fumin Dai, Hongyan Ma, Xiaobing Dai, Zhen Li, Xingwen Jia, Jueshi Qian

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study aims at the development of magnesium phosphate cement-based ultra-high performance concrete (MPC-UHPC). To this end, MPC paste phase was designed by using high magnesia-to-phosphate (M/P, 3.5) and low water-to-cement (W/C, 0.10–0.16) mass ratios, and certain amounts of ultra-fine fly ash (UFA, 5%–15%). Fresh and hardened properties, and microstructure of the developed MPC-UHPC were evaluated, and compared with those of conventional UHPC as well. Test results showed that lower W/C resulted in higher mechanical strengths and lower drying shrinkage, but the sharp decrease of workability and increase of autogenous shrinkage. At a constant W/C, the addition of UFA effectively …

Pumping Of Concrete: Understanding A Common Placement Method With Lots Of Challenges, Dimitri Feys, Geert De Schutter, Shirin Fataei, Nicos S. Martys, Viktor Mechtcherine

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Several million cubic meters of concrete are pumped daily, as this technique permits fast concrete placement. Fundamental research has been performed and practical guidelines have been developed to increase the knowledge of concrete behavior in pipes. However, the pumping process and concrete behavior are not fully understood. This paper gives an overview of the current knowledge of concrete pumping. At first, the known physics governing the flow of concrete in pipes are introduced. A series of experimental techniques characterizing concrete flow behavior near a smooth wall to predict pressure-flow rate relationships are discussed, followed by recent developments in the use …

Effect Of Carbon Nanotube And Graphite Nanoplatelet On Composition, Structure, And Nano-Mechanical Properties Of C-S-H In Uhpc, Huanghuang Huang, Le Teng, Xiaojian Gao, Kamal Khayat, Fazhou Wang, Zhichao Liu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper studied the influence of carbon nanotube (CNT) and graphite nanoplatelet (GNP) used at 0 to 0.3%, by mass of binder, on composition, structure, and nano-mechanical characteristics of C-S-H of ultra-high performance concrete (UHPC). Hydration kinetics, pore structure, and mechanical properties of UHPC were also investigated. The non-proprietary UHPC was proportioned with 17% lightweight sand for internal curing. Test results indicated that the addition of 0.3% CNT or GNP led to approximately 20 MPa increase in compressive strengths of non-fibrous UHPC mortar and fibrous UHPC (2% steel fibers), compared to those prepared without any nanomaterial. Such enhancement is attributed …

Design Challenges Of Solving Circular Geometry In Residential Buildings, Rayan Zankar, Lana El-Kaaki, Jameel Fares

Architecture and Planning Journal (APJ)

A dimensional geometrical shape such as a circular shape has been established all throughout the history of building design planning in order to find out the suitable arrangements for the living spaces: One of the most unusual designs planning in architecture is circular planning. Moreover, residential buildings that contain a circular plan are not built that frequently as well, but they still are a part of architecture since prehistoric times. Unfortunately, there are significant issues in such buildings, such as a structural challenge within the design module with orientation problems. In other words, there is a missing of the optimum …

Evaluating The Low-Temperature Properties Of Asphalt Binders Extracted From Mixtures Containing Recycled Materials, Eslam Deef-Allah, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The use of recycled materials − such as reclaimed asphalt pavement (RAP) and recycled asphalt shingles (RAS) − in asphalt mixtures reduces natural resources demands and decreases materials dumped in landfills. The aged binders included in the recycled materials alter binders' low-temperature properties included in asphalt mixtures. Therefore, asphalt binders were extracted from asphalt mixtures collected from the field as cores. Due to the limited amount of extracted asphalt binders (EABs), a dynamic shear rheometer was used to examine the low-temperature properties [e.g., true temperature (Tt), continuous temperature (Tc), and delta continuous temperature (ΔTc)]. Using recycled materials in asphalt mixtures …

A Neural Network-Based Multivariate Seismic Classifier For Simultaneous Post-Earthquake Fragility Estimation And Damage Classification, Xinzhe Yuan, Genda Chen, Pu Jiao, Liujun Li, Jun Han, Haibin Zhang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A scalar intensity measure (IM) could be insufficient to represent the earthquake intensity and variety in fragility estimation. Introducing multiple IMs to conventional regression of fragility functions can be computationally demanding and require priori assumptions of functional forms. In this study, multivariate seismic classifiers with multiple IMs as inputs are developed based on artificial neural networks (ANNs) to address the above disadvantages of traditional regression approaches. Case studies of a four-story code-conforming benchmark building indicate that fragility estimates from multi-IM ANN classifiers lead to higher accuracy (5.0% to 7.7%) in system-level and element-level damage classification than the single-IM traditional fragility …

Components’ Exchanges Between Recycled Materials And Asphalt Binders In Asphalt Mixes, Eslam Deef-Allah, Magdy Abdelrahman, Mohyeldin Ragab

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The focus of this study was to explore the components' exchanges between recycled asphalt shingles (RAS) or reclaimed asphalt pavement (RAP) and virgin asphalt binders (VABs) in the asphalt mixes and to establish their effect on the rutting resistance of the extracted asphalt binders (EABs). Twelve plant mixes and twelve field mixes were gathered as examples of four Superpave mixes containing RAP or RAS. The plant mixes were reheated and compacted in the lab. The field mixes were collected as cores within 2 weeks after the ending of the construction process. The exchanged components were investigated using Fourier transform infrared …

M&S Highlight: De Larrard Et Al. (1998) Fresh Concrete: A Herschel-Bulkley Material, Dimitri Feys

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.

Influence Of Phosphorus Sources On The Compressive Strength And Microstructure Of Ferronickel Slag-Based Magnesium Phosphate Cement, Cuirong Yan, Hongyan Ma, Zhongqiu Luo, Xintao Zhou, Luxing Wang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Electric furnace ferronickel slag (EFS) is a typical magnesium-rich industrial by-product discharged from the manufacture of nickel and iron-nickel alloys. The approach to use it as the raw material for the preparation of magnesium phosphate cement (MPC) has potential and proves effec-tive. In this study, three different phosphorus sources (PS) including phosphoric acid (H3 PO4, PA), sodium dihydrogen phosphate (NaH2 PO4, SDP) and potassium dihydrogen phosphate (KH2 PO4, PDP) were used to react with EFS to prepare the EFS-based MPC (EMPC), and the effects of raw material mass ratio (EFS/PA, EFS/SDP, EFS/PDP) on the compressive strength, early hydration temperature and …

Simplified Analytical Model To Assess Key Factors Influenced By Fiber Alignment And Their Effect On Tensile Performance Of Uhpc, Le Teng, Huanghuang Huang, Kamal Khayat, Xiaojian Gao

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The increase in single-fiber pullout strength usually improves tensile strength and toughness of UHPC. An increase in fiber orientation angle (θ) up to 45° to the direction of pullout load was found to enhance the single-fiber pullout strength. However, such increase in predominant θ value along tensile strength specimens led to a reduction in tensile strength of UHPC. In order to elucidate this controversial observation, analytical models combined with experiments were carried out to assess the key factors influencing the tensile properties of UHPC due to variations of fiber orientation. The test parameters involved the evaluation of the effect of …

Revealing Bluff-Body Aerodynamics On Low-Rise Buildings Under Tornadic Winds Using Numerical Laboratory Tornado Simulator, Ryan Honerkamp, Guirong Grace Yan, John Van De Lindt

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Tornadoes result in death and property loss in communities around the world. To quantify the actions of tornadoes on civil structures, researchers have built physical laboratory tornado simulators to simulate tornadoes in the lab environment and tested building models in the simulated tornadic wind field, which is similar to wind tunnel testing when quantifying the wind effects induced by straight-line winds. Unfortunately, physical tornado simulators are much less common than straight-line wind tunnels, leading to the lack of research on bluff-body aerodynamics on civil structures under tornadic winds. Considering that it is expensive to conduct experimental testing in physical tornado …

Bc-Dunet-Based Segmentation Of Fine Cracks In Bridges Under A Complex Background, Tao Liu, Liangji Zhang, Guoxiong Zhou, Weiwei Cai, Chuang Cai, Liujun Li

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Crack is the external expression form of potential safety risks in bridge construction. Currently, automatic detection and segmentation of bridge cracks remains the top priority of civil engineers. With the development of image segmentation techniques based on convolutional neural networks, new opportunities emerge in bridge crack detection. Traditional bridge crack detection methods are vulnerable to complex background and small cracks, which is difficult to achieve effective segmentation. This study presents a bridge crack segmentation method based on a densely connected U-Net network (BC-DUnet) with a background elimination module and cross-attention mechanism. First, a dense connected feature extraction model (DCFEM) integrating …

Spatiotemporal Analysis Of Urban Road Congestion During And Post Covid-19 Pandemic In Shanghai, China, Pengfei Xu, Weifeng Li, Xianbiao Hu, Hangbin Wu, Jian Li

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Coronavirus Disease 2019 (COVID-19) has become one of the most serious global health crises in decades and tremendously influence the human mobility. Many residents changed their travel behavior during and after the pandemic, especially for a certain percentage of public transport users who chose to drive their owned vehicles. Thus, urban roadway congestion has been getting worse, and the spatiotemporal congestion patterns has changed significantly. Understanding spatiotemporal heterogeneity of urban roadway congestion during and post the pandemic is essential for mobility management. In this study, an analytical framework was proposed to investigate the spatiotemporal heterogeneity of urban roadway congestion in …

A Case Study Of Community-Engaged Design: Creating Parametric Insurance To Meet The Safety Needs Of Fisherfolk In The Caribbean, Daniel B. Oerther

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The creation of the Caribbean Ocean and Aquaculture Sustainability faciliTy (COAST) is used as a case study of community-engaged design addressing safety needs. COAST is a parametric insurance product, sold to national governments, which was designed to meet the food and nutrition security of small- and medium-scale fisherfolk. The design of COAST is an example of convergence research, where the discipline of engineering was integrated with another discipline to solve pressing societal needs of Caribbean fisherfolk. This case study demonstrates that community-engaged design helps to (1) identify and include historically underrepresented stakeholders, (2) emphasize the importance of professional responsibility for …

The Impact Of Light Rail Transit On The Urban Development In Dubai, Uae, Dhabia Nasser Alhazmi Alefari

Theses

The United Arab Emirates (UAE) has seen significant growth in urban development over the past two decades. To overcome the implication of this development, Dubai’s Roads and Transport Authority (RTA) has called for sustainable transport development at all levels, including the Light Rail Transit (LRT), which is a friendly mass transit system to satisfy the requirements of urban mobility, environmental sustainability, and green power efficiency. The shift towards sustainable mass transport systems has become the ideal choice to overcome the challenges accompanying the growth and development facing cities such as Dubai and to convert them into sustainable environmentally friendly places. …

Solving The Negative Earnings Dilemma Of Multistage Bidding In Public Construction And Infrastructure Projects: A Game Theory-Based Approach, Muaz O. Ahmed, Islam H. El-Adaway, Kalyn T. Coatney

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

With the tremendous increase in spending on public projects, contractors need to employ efficient and effective bidding strategies to cope with the competitive bidding environment. Usually, general contractors carry a portion of the work and subcontract other parts to eventually submit a holistic joint bid. This bidding setting is referred to as multistage bidding where subcontractors submit their quotations/bids to the general contractor, after which the general contractor submits a final joint bid for the whole project. In a multistage bidding environment, general contractors may be faced with an increase in the probability of negative or below normal profits. Despite …

Understanding Effects Of Permafrost Degradation And Coastal Erosion On Civil Infrastructure In Arctic Coastal Villages: A Community Survey And Knowledge Co-Production, Min Liew, Ming Xiao, Louise Farquharson, Dmitry Nicolsky, Anne Jensen, Vladimir Romanovsky, Jana Peirce, Lilian Alessa, Christopher Mccomb, Xiong Zhang, Benjamin Jones

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents the results of a community survey that was designed to better under-stand the effects of permafrost degradation and coastal erosion on civil infrastructure. Observations were collected from residents in four Arctic coastal communities: Point Lay, Wainwright, Utqiaġvik, and Kaktovik. All four communities are underlain by continuous ice-rich permafrost with varying degrees of degradation and coastal erosion. The types, locations, and periods of observed permafrost thaw and coastal erosion were elicited. Survey participants also reported the types of civil infrastructure being affected by permafrost degradation and coastal erosion and any damage to residential buildings. Most survey participants reported …

Funicular Shell Exploration: Form Finding And Fabrication, Alexis Truong, Adria Burton, Ethan Mach

Architectural Engineering

Analysis and evaluation of interdisciplinary challenges associated with integrating the design and construction processes to deliver innovative thin shell structures.

Arce 415 Portfolio, Jay Skaff, Audrey Williams, Sarah Tom

Architectural Engineering

The purpose of this studio is to design a sun shelter for children at the SLO Botanical Gardens. It will be used for outdoor presentations and learning experiences. When coming up with the initial design of the shell structure for the SLO Botanical Gardens, the team needed to consider the material being used, the constructability of the structure, the people who would be using the structure, and the overall lifespan of the shell.

Guastavino: Learn By Doweling, Audrey Luu, Gabrielle Favro, Robert Pulido, Cameron Grant

Architectural Engineering

We embarked on a journey into the world of shells this quarter! We began the process with form finding using rhino and grasshopper. Then made a study model using laser cutters to brainstorm ways to construct the real-life model. As a class, we completed two shell structures.

Development Of The Human Scale Twelve-Node Model, Tebrez W. Khan

Architectural Engineering

The attempted creation of a full-scale twelve-node model made of PVC pipe and golf balls. Intended use of the structure was for students to tactically learn from the model.

Population Growth Vs. Landfill Capacity Vs. Recycling Mandates In California Counties, Thomas Soares

Architectural Engineering

As population growth increases in Monterey, Fresno, Kern, San Luis Obispo, Santa Barbara, and Ventura counties, so does waste production. More waste is a cause for concern because landfills have limited capacities. In order to combat the increase in waste, cities, counties, and the state are creating recycling mandates to ensure waste is being handled appropriately. More specifically, the trash generated by residents and construction and demolition (C&D) materials are being recycled and reused instead of thrown into landfills. This report indicates that increases in recycling mandates in California cannot withstand the increase in waste generation from population growth. Another …

Team Torroja, Justine Teoh, Lindsey Brophy, Brandon Watrin

Architectural Engineering

For this project, we were tasked with designing a sun shelter by SLO Botanical Gardens for their Children's Garden. It was requested that the form by derived from structural shells. The structure is to serve as a multi-purpose space to host a variety of activities on the 30 foot by 60 foot site.