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Fire Protection Analysis of a K-12 Classroom Building
Get PDFThe report evaluates the fire protection features of a K-12 classroom building (Bldg. B) in San Bernardino County, California. Bldg. B is a two-story Type V-A light timber frame construction. At the time of this report’s composition, Bldg. B is undergoing modernization construction. The fire protection analysis of this building consists of prescriptive and performance portions.
The prescriptive analysis verifies the compliance of building egress, passive, and active protection features with the 2019 edition of California Codes of Regulations Title 24 (Title 24) and Title 24-adopted National Fire Protection Association (NFPA) standards. The analysis comprises of four sections: egress, structural analysis, fire alarm design, and sprinkler system analysis. The egress section describes the occupancy classifications and assesses the occupant loads, the required width for exits and exit access doorways, the number of available fire escapes, exit separation distance, and interior finishes. The structural analysis section focuses on the modernization expansion area increase, the building elements’ fire-resistance rating, and fire separation requirements. The fire alarm section surveys the location of alarm devices, determines the spacing requirements, identifies active smoke control in place, and diagnoses the secondary power supply. The sprinkler system analysis section checks the fire suppression device coverage and the required hydraulic pressure for the chosen remote design areas. Overall, the fire protection features in Bldg. B follow the prescriptive codes of regulation in effect at the time of modernization design, and implicit safety is accomplished.
The performance-based analysis gauges the effectiveness of prescriptive active fire protection systems in providing explicit safety to occupants in Bldg. B using three design fires. Locations of these fires are selected based on potential life safety impacts. The heat release rates of the design fires reference fuel load data from SFPE Handbook and Nuclear Regulatory Commission (NUREG) literature.
To achieve explicit safety, the available safe egress time (ASET) for a design fire must exceed the required safe egress time (RSET).
Before ASET is estimated, a set of tenability criteria on visibility, toxicity, radiant heat exposure, and flashover has to be established. The exceedance of any one tenability criterion signifies the expiration of ASET. Computational fire dynamics is used to find the ASET of a design fire.
RSET is based on egress component width, space density, occupant familiarity with the building, and population size. Using hydraulic flow model, NIST Egress Estimator, and Thunderhead Engineering’s Pathfinder software, the full-evacuation time for the entire building is predicted to be 4.87 minutes. RSET is then further refined for individual design fire scenario.
The first design fire (DF-1) is on the first-floor Flex Studio 2 137. Flex Studio 2 137 and the adjacent Flex Studio 1 136 are significant exit access areas where occupants of nearby classrooms and north wing 2nd-floor occupants must go through to reach building exits. If egress is disabled for the area, occupants in nearby spaces would be trapped. Using hydraulic flow model and Pathfinder, RSET for DF-1 is calculated to be 2.81 minutes. DF-1 is then put into Pyrosim to estimate ASET. After analyzing simulation results, DF-1 ASET is found to be visibility driven, as incapacitation, radiant heat exposure adverse outcome, and flashover are unlikely. When significant sub-4m visibility pockets appear along the wall around 3.14 minutes, visibility tenability expires for DF-1. As such, for DF-1, ASET (3.14 minutes) is greater than RSET (2.81 minutes); explicit safety is achievable. Another ASET vs RSET analysis is performed for the 2nd-floor because smoke may travel through the now unenclosed Stair B unimpeded and impair egress. Pyrosim predicts the visibility would remain above 30 meters during RSET. As such, ASET is also greater than RSET for the 2nd-floor spaces above DF-1.
The second fire (DF-2) is in the library reading area. An ASET vs RSET comparison is done, and occupants would be able to escape in time through the available exits. The concerns then become property damage mitigation and life safety in adjacent spaces. Using Pyrosim, the sprinkler system is predicted to activate at 61 seconds, keeping the HRR at 400 kW. With the activation of automatic fire sprinklers, the risks of flashover and property damage are low.
The third fire (DF-3) is in the first-floor electrical room near the elevator shaft and a main building exit. The concern is a possible flashover. A two-zone model is constructed in CFAST which predicts that the sprinkler system would activate 45 seconds and freeze the HRR at 130 kW, far below the lowest predicted flashover HRR of 1053 kW. Therefore, flashover is not expected and DF-3’s impact on adjacent space egress is minimal.
The results of performance analysis are favorable. Explicit safety is attainable with functional active fire protection systems
Development of the New Hasslein CAED Collaborative
Get PDFThis paper outlines the development and execution of the new Hasslein CAED Collaborative student competition which engages students of all five majors in the College of Architecture and Environmental Design in a Request for Proposal style competition. CAED houses students studying Architecture, Architectural Engineering, City and Regional Planning, Construction Management, and Landscape Architecture. There is little opportunity for interdisciplinary collaboration within the CAED, despite our future career paths being heavily intertwined. This competition followed research by Greta Stout, class of 2022, on the benefits and support of interdisciplinary collaboration at Cal Poly SLO in CAED. The competition is named after George Hasslein, the founding dean of CAED in 1968, who advocated for an interdisciplinary curriculum. This paper focuses on the administration of the competition, writing the problem statement, and seeking industry support from the Alliance Foundation and Cal Poly SLO faculty. Participants were asked to compile a proposal for the provided problem statement and present their solution to a panel of judges. The competition was created to expose students to collaboration in our industry and prepare students for their careers in the industry
Feasibility Assessment of an All-Electric, Narrow-Body Airliner
Get PDFCombustion emissions from aviation operations contribute significantly to climate change and air pollution. Accordingly, there is increasing interest in advancing battery-powered propulsion for aviation applications to reduce emissions. As batteries continue to improve, it is essential to recognize breakthroughs in battery specific energy in the context of air transport vehicles. Most electric aircraft designs and programs have focused on small aircraft because of restrictive battery performance. This work presents a feasibility assessment for an all-electric airliner based on an Airbus A220-100 with turbofan engines replaced by electric motors and propellers. The analysis compares the performance characteristics of the electric airliner to the A220-100 and establishes several configurations with varying battery pack-specific energy. The short-term electric airliner could replace conventional aircraft on very short, high-density missions.
In contrast, the long-term electric airliner requires significant battery technology improvements that are not currently foreseen. The alternative long-term electric airliner could complete half of the A220-100’s missions, but the necessary specific energy value is also not anticipated shortly. All-electric airliners would significantly impact manufacturing, operations, costs, and emissions but are commercially infeasible with current battery technology. Additional development of more advanced battery technology is required to increase the specific energy of battery packs, enhance battery safety and reliability, and develop lighter high-power electric motors
The Complex Intersections of Being a Latina Immigrant Survivor: How Multiple Systems of Oppression Enable Intimate Partner Violence
Get PDFThe realm of intimate partner violence education, prevention and awareness is one that is currently growing. Even though there are improvements happening, there are communities being left out of both the movement and body of research. This paper aims at connecting the stories of undocumented Latinas who are survivors of intimate partner violence in the central coast of California with the current body of research on immigrant survivors. In doing so, it seeks to explore the areas where the body of research matches the stories of these women in the central coast of California and where there is a lack of knowledge from both the efforts in this field and the body of research. The stories of immigrant survivors shared in this report were collected by RISE on January 2015 to March 2015. RISE serves as a non-profit organization and resource for survivors and their families of sexual assault and intimate partner violence in San Luis Obispo County in California. RISE provided services to these women in one of their three locations in the San Luis Obispo County and who had experienced abuse as closely as a month prior to the January 2015 survey to five years
Intertidal No. 1
Get PDFFor the first year ever, Intertidal has surfaced to showcase the art of Cal Poly\u27s students and faculty. An \u27intertidal zone\u27 is an area where the ocean meets the land--hidden during the high tide and exposed during the low. Our journal embodies the moment where the tide recedes, revealing stories previously hidden
What Does the Geometry of the HβBLR Depend On?
Get PDFWe combine our dynamical modeling black-hole mass measurements from the Lick AGN Monitoring Project 2016 sample with measured cross-correlation time lags and line widths to recover individual scale factors, f, used in traditional reverberation-mapping analyses. We extend our sample by including prior results from Code for AGN Reverberation and Modeling of Emission Lines (CARAMEL) studies that have utilized our methods. Aiming to improve the precision of black-hole mass estimates, as well as uncover any regularities in the behavior of the broad-line region (BLR), we search for correlations between f and other AGN/BLR parameters. We find (i) evidence for a correlation between the virial coefficient log10(fmean,σ) and black-hole mass, (ii) marginal evidence for a similar correlation between log10( frms,σ) and black-hole mass, (iii) marginal evidence for an anticorrelation of BLR disk thickness with log10( fmean,FWHM) and log10( frms,FWHM), and (iv) marginal evidence for an anticorrelation of inclination angle with log10( fmean,FWHM), log10( frms,σ), and log10( fmean,σ). Last, we find marginal evidence for a correlation between line-profile shape, when using the root-mean-square spectrum, log10(FWHM/σ)rms, and the virial coefficient, log10( frms,σ), and investigate how BLR properties might be related to line-profile shape using CARAMEL models
An Analysis on Wildfire Mitigations Employed by Utilities in California
Get PDFAs climate change continues to worsen, environmental effects are felt by many people around the world. In California, some of its most damaging wildfires have been found to be started by utilities. As the state continues to suffer from worsening wildfire conditions, the utilities need to implement a variety of wildfire mitigations to help reduce the risk of wildfires that can affect the state and its residents. This paper analyzes the effectiveness of four mitigations employed across three California utilities and suggests potential ways for the mitigations to be used together. The technologies evaluated are covered conductor, rapid earth fault current limiter, distribution fault analysis, and early fault detection. Each of these mitigate different failure drivers of utility lines, whether it is due to a contact from a foreign object, an equipment failure, or another driver. Because each mitigation is more effective against different drivers, a suggestion for multiple mitigations to use together is given. This also includes a path for utilities to evaluate mitigation effectiveness in a different way that may more accurately represent how many fires are stopped by the mitigations employed