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SRS Training Facility
Get PDFThis report presents a comprehensive fire protection and life safety analysis of the Savannah River Site (SRS) Training Center. A detailed prescriptive code analysis confirmed the building\u27s compliance with applicable standards regarding construction features, occupancy classification, and fire-rated assemblies. Fire resistance provisions are met, with key areas such as exits, stairwells, and the records storage room. The building’s layout, height, number of stories, and floor area also comply with the allowable limits established by the IBC. Fire protection systems include a proprietary fire alarm system with voice notification, extensive smoke and heat detection coverage, and a wet-pipe sprinkler system designed in accordance with NFPA 13 requirements. The kitchen is protected by a wet-chemical system installed in accordance with NFPA 96. Water supply capacity was found to exceed demands, with dual storage tanks and multiple fire pumps ensuring redundancy. Life safety features, including exit signage, interior finishes, and means of egress, were evaluated. While most areas exceed code requirements, the second floor’s egress capacity is marginal when excluding one open stairwell, highlighting a potential need for improved evacuation options.
The performance-based analysis was conducted using Fire Dynamics Simulator (FDS) and Pathfinder modeling to evaluate three (3) fire scenarios, focusing on factors such as tenability thresholds, occupant behavior, and safe egress time. Key performance metrics included Required Safe Egress Time (RSET) and Available Safe Egress Time (ASET). Fire scenarios addressed in this report include a fire that originates in the Records Storage Room, a workstation fire in an open office area, and a couch fire in the waiting space. Results demonstrated that the building’s fire protection and egress strategies are sufficient under most conditions, though performance is reduced when specific egress components are inaccessible.
Overall, this report concludes that the SRS Training Center meets the essential requirements for fire and life safety, though minor improvements in egress capacity could further enhance safety and resilience. Recommendations include reducing the occupant load of the Second Floor and/or ensuring the East stairwell is utilized only as a secondary/alternate means of egress
DeepPanoRF: Deep Prior for Neural 3D Reconstruction From Sparse Panoramas
No full textAdvances in neural field representations have led to a significant improvement in view synthesis quality. However, many current novel view synthesis methods rely on a dense set of input views, which can be impractical and inefficient in real-world applications. We propose DeepPanoRF, a novel method for 360◦ scene reconstruction from a sparse set of input equirectangular panoramas. Built upon K-Planes, a radiance field representation that encodes explicit features on orthogonal feature planes, our method does not directly learn feature grids. Instead, we parameterize the feature grids to enable sparse view reconstruction without pretraining or additional regularization. We implement a custom U-Net architecture to take advantage of the encoder-decoder network and the skip connections. We evaluate our method’s effectiveness on the Habitat-Matterport 3D (HM3D) dataset, which consists of diverse, high-quality indoor environments. Our results demonstrate that DeepPanoRF outperforms K-Planes in both reconstruction quality and structural coherence when dealing with sparse input views
Cementing CO2 into C-S-H: A Step Toward Carbon Neutrality, Or a Step in the Wrong Direction?
No full textAs greenhouse gas emissions continue to rise, many in the construction industry are looking for sustainable solutions to reduce its carbon footprint. One of the biggest contributors to atmospheric CO2 comes from cement production. In 2023, researchers at MIT explored ways to enhance concrete’s natural ability to act as a carbon sink. Concrete does this unassisted through a chemical reaction called carbonation, by which atmospheric carbon bonds to key components in cement. The researchers at MIT proposed a process of early-stage forced carbonation, which can be induced by the addition of NaHCO3 into a standard concrete mix. Sodium bicarbonate, or baking soda, allows atmospheric carbon to be converted into a mix of calcite, C-S-H, and disordered calcium carbonate. According to the researchers, this additional chemical process does not compromise cement’s structural integrity. The team tested samples with 0, 5, 10, 15, and 20% sodium bicarbonate to portland cement by weight and found that the control sample slightly outperformed the carbonated solutions, but not by a statistically significant margin in terms of its structural integrity. Unlike cement, concrete is a mixture of coarse and fine aggregates, water, and cement, which acts as the binder. Key components in its construction are workability, how easily it can be poured into set shapes with sufficient time to ensure there aren’t any voids after it is poured, and its durability in terms of its compressive strength. While the research team at MIT claimed the hardness of the alternative cement mixture was comparable to a standard mix, hardness and compressive strength are fundamentally different measures, with hardness having less relevance to performance as a structural material. Likewise, the team only measured up to 7 days, while concrete strength, per ASTM standards, is measured at the 28 day mark. While the published research presented a more environmentally friendly alternative to a 5 standard cement mix, it also failed to explore the key physical properties that are crucial to its widespread adoption in the construction industry. To research these properties, a standard concrete mix design was substituted with 0, 10 and 20% cement-to-baking soda percentages by weight and loaded in a Test Mark machine to determine its compressive strength at 7 and 28 days, in addition to its tensile strength at 28 days. Tests were conducted in accordance with the established industry standards for testing the behavior of concrete, outlined in ASTM C39 and C496. These results were then compared to standard to determine the viability of sodium bicarbonate as a potential admixture in the construction industry
Investigating Social Presence in Collaborative Keys for Asynchronous Courses
Get PDFAsynchronous virtual courses have become increasingly popular in the years following the global Covid-19 pandemic. These courses, with no set meeting schedule, offer flexibility to both students and instructors, but pose challenges for developing a collaborative learning environment. The Community of Inquiry framework (Rourke et al., 1999) identifies three essential components in an online course necessary to foster a collaborative environment- teaching presence, cognitive presence, and social presence. Social presence is especially impacted in asynchronous learning settings, which presents challenges for the students to display their personalities and connect with the community. This study investigates Collaborative Keys (CKs), structured collaborative assignments given in an asynchronous class, to help remedy the lack of social interaction. Data were collected on Cal Poly students in an introductory statistics class in Winter 2023 on various indicators of social presence in the assigned CKs. This research examined the presence of social interactions over the duration of a quarter and their changes over time. Overall, high levels of social presence were observed in the CKs, suggesting they were successful in cultivating student engagement. Additionally, the relationship between social presence and academic performance in the course was investigated. Results include a significant positive association between the rate of cohesive social presence and student performance and a significant negative association between the rate of self-disclosure and student performance. These results will inform pedagogical approaches that incorporate collaborative learning into virtual environments and improve students’ experiences in asynchronous modes of instruction
