Most studies on blast explosion focus on a single technique or software. This Thesis directly compares several methods of simulating blast loads using LS-DYNA, ABAQUS and CTH software. The techniques appraised in this thesis include; Jones-Wilkins-Lee (JWL) equation of state (EOS), spherical incident wave formulation, and a direct planar blast load application. In the first section of this study, we analyzed a free air-blast generated by detonating 100 g of composition-4 (C-4). Next, we placed and examined the lower extremity model under the same blast parameters in different coupled and uncoupled scenarios. In the free air-blast study, all three codes gave similar results. The peak over pressure from ABAQUS was the closest in value to the experimentally measured data. In the second section, the JWL EOS method consistently produced higher-pressure response in the lower extremity elements compared to the other methods implemented.

This thesis endeavors to comprehensively examine and elucidate the factors and challenges that have shaped the city of Beirut, Lebanon into its current state. Extensive research has shed light on numerous incidents, which can be regarded as defining moments that have imbued the city with its distinct character and identity. Among these events, the pivotal occurrence that triggered the ongoing turmoil within Beirut is the catastrophic Beirut Blast of August 4th, 2020. This incident serves as the focal point of the thesis, aiming to foster unity while embracing the city's authenticity and showcasing the visible wounds through architectural expressions. It represents a conscious acknowledgment of the past as a means to propel transformation and shape the future. The thesis project presents seven distinct scenarios, each encapsulating a significant dichotomy in Beirut's history and its enduring impact on the city's present. The objective is to cultivate a considerate architecture that not only serves the needs of the population but also respects and nurtures the surrounding natural environment. By revitalizing and promoting biodiversity in both aquatic and terrestrial realms, an attempt is made to establish a dialogue between the city and the site of the catastrophe. This dialogue serves as a platform for reconciliation, paving the way for Lebanon's long-term welfare. The envisioned spaces encompass public areas, educational facilities, and spaces for healing, effectively becoming sanctuaries that hold multifaceted significance. These architectural interventions aspire to provide value that extends beyond mere physical structures, enhancing the overall fabric of the city. / Master of Architecture / In this research project, I aim to explore the factors and challenges that have shaped Beirut, Lebanon into its current state, with a focus on the city's unique identity. I have conducted extensive research, uncovering significant events that have influenced the city's character. Among these, the Beirut Blast of August 4th, 2020, stands out as a pivotal moment that triggered ongoing turmoil. The thesis aims to bring people together while embracing Beirut's authenticity and showcasing the visible scars through architectural expressions. Through the project, I present seven scenarios that represent important dichotomies in Beirut's history and their lasting impact on the city today. The goal is to create thoughtful architecture that not only meets the needs of the population but also respects and nurtures the natural environment. By revitalizing and promoting biodiversity in both land and water, I seek to establish a dialogue between the city and the blast site. This dialogue serves as a platform for reconciliation and contributes to Lebanon's long-term well-being. The envisioned spaces include public areas, educational facilities, and healing spaces, serving as sanctuaries with multiple layers of significance. These architectural interventions aim to go beyond physical structures and enrich the fabric of the city, providing value and enhancing the overall experience for its residents and visitors.

One of the principal challenges of primary blast injury research is imitation of shock waves accurately and consistently in a safe and tunable platform. Existing simulators have been effective in these goals but have not been conducive for in vitro models due to their large size and air-mediated wave propagation. In this thesis, a redesigned benchtop shock wave generator (SWG) has provided a platform for in vitro models. A pulsed power generator charges a capacitor and discharges the capacitor through a bridge wire. The discharge causes the bridge wire to experience phase changes, momentarily becoming a gas or plasma. In this moment, the bridge wire expands radially and creates a pressure wave in the surrounding water. As the wave propagates, it forms a shock wave and strikes the cell platform at the far end of the conical tank. Current design efforts are focused on the tunability of the SWG, by varying the bridge wire material and diameter. Five materials at three bridge wire diameters have been tested. Each bridge wire was inserted into the SWG via a pinching mechanism. Either side of the pinching mechanism was connected to either terminal of the capacitor. When the pulsed power generator was cycled, the bridge wire was vaporized and generated a shock wave. A piezoelectric sensor near the wide end of the tank recorded the passing of the shock wave, which was used to derive various pressure metrics that correlate to injury. The sample size for each combination of diameter and material was five, with a grand total of seventy-five samples run. Two-way ANOVAs measuring the impacts of bridge wire material and diameter on a variety of shock wave metrics found that the diameter played a significant role in determining the peak overpressure and positive impulse generated while the main effect of material played a much smaller role. The interaction between material and diameter was also found to be significant. The tunable benchtop SWG provides a platform for exploration of primary blast injury using in vitro models. By adjusting the bridge wire diameter, the SWG can generate waves with a variety of shock wave metrics, providing an opportunity for researchers to address various degrees of injury. With the addition of this technology to the efforts to understand primary blast injury, development of treatments and protective equipment can be expedited. / Master of Science / Primary blast injury, the injury caused by the blast wave moving through the body, has been affecting those exposed to blast for nearly a century, since the regular use of conventional explosives in World War I. As equipment and war has changed in the past two decades, there has been heightened interest in understanding the effects of blast waves on the body. To assist in this research, blast wave simulators have been developed to recreate the blast wave in a controlled environment. However, current designs are not conducive to experiments on cultured cells. A new blast wave simulator, called the shock wave generator (SWG), has been designed as a platform for cultured cell-based experiments. The simulator generates a shock wave by exploding a thin bridge wire using high electrical current. The explosion occurs underwater, generating a shock wave capable of injuring cells at the opposite end of the tank. A platform such as this provides multiple opportunities to tune the pressure metrics related to the shock waves. Bridge wire material and volume play critical roles in the resulting shock wave, working together to define the amount of energy required to vaporize the bridge wire. Five materials and three diameters, a derivative of the wire volume, were investigated to determine their impacts on the resulting peak pressure, positive duration, and positive impulse. While wire material was not found to have a significant impact on peak pressure, wire diameter had a significant effect on the resulting overpressures. The thickest wire generated the lowest peak pressure while the thinner wires generated higher peak pressures. The thinner wires were not significantly different from one another. A similar result was found for positive duration and impulse. Overall, the use of an exploding wire to generate shock waves is applicable as an injury mechanism for cell cultures in primary blast injury research. This work along with future work will provide a tunable and controlled platform that has opened a new frontier for investigating the primary blast injury.

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Recent interest in sustainable design has resulted in timber products being considered for a variety of construction projects. This has especially been the case for engineered wood products (EWPs), such as glue-laminated timber (glulam) and cross-laminated timber (CLT). Research into the performance of these massive timber products has been ongoing, where the methodology employed has generally favoured experimental approaches on undamaged members, combined with simplified analytical methods. Relatively little attention has been given to more sophisticated numerical methodologies and to the effects of repeated loadings on the same specimen. This study intends to contribute to the literature by investigating the viability of full-scale finite element models to simulate the behaviour of timber elements at high strain rates and proposing a generalized structure for dynamic models that is capable of adequately recreating realistic failure modes. Three glulam specimens and three CLT specimens were subjected to simulated blast loads under four-point bending with simply supported boundary conditions using the University of Ottawa Shock Tube Test Facility. The behaviour of the glulam specimens during the dynamic testing was consistently linear-elastic until flexural failure was reached. Conversely, the failure behaviour of CLT panels was more complex and included flexural failure, rolling shear failure, or a combined behaviour where both modes developed simultaneously. Single-degree-of-freedom (SDOF) and finite element analysis (FEA) methodologies were used to predict the behaviour in terms of displacement-time histories and failure modes. The inputs for the analytical methods relied on values sourced from literature or manufacturer data. A finite element (FE) material model was implemented into ABAQUS/Explicit through a dynamic user subroutine (VUMAT). The model used continuum damage mechanics to alter the material stiffness matrix once the elastic strengths were exceeded. SDOF analysis was shown to effectively predict the maximum mid-span displacement of glulam members subjected to blast loads, within a 20% error margin. However, the model was found to be incapable of consistently predicting the displacement and time of failure, especially for CLT panels, where up to 50% error was observed. This degree of error was attributed to the model’s inability to account for multiple failure modes, namely rolling shear and flexural failure. The resistance curves implemented in the SDOF models generally agreed with experimental results, particularly with regard to initial stiffness, and were deemed sufficiently accurate from the perspective of design. The finite element models simulated specimen ultimate behaviour reasonably well. Relatively accurate analytical predictions were also obtained for both maximum mid-span displacements and corresponding times. However, computational issues with damage transfer prevented the modeling of repeated tests on CLT panels. The FE model was capable of producing resistance-displacement relationships which correlated well to experimental results, despite the presence of numerical fluctuations. This is a significant outcome for the potential application of FEA to blast behaviour of timber components, since SDOF models require resistance curves as input and are unable to predict the force-displacement response of members.

Ultra-high performance fiber-reinforced concrete (UHPFRC) is an advanced cement-based composite with enhanced compressive strength, tensile resistance and toughness when compared to conventional concrete. Interest in the application of UHPFRC as a retrofit material has been rapidly increasing, and a few existing studies have examined the ability of UHPFRC to retrofit and strengthen existing reinforced concrete (RC) structures under static loading; however, very limited studies have examined the effectiveness of UHPFRC to improve the response of RC members under blast loading. This thesis aims at filing this research gap and investigates the behavior of UHPFRC retrofitted RC flexural members under both static and blast loads. A total of twenty-one (21) specimens, in two different series are tested. Series 1 includes nine (9) singly-reinforced beams built with high-strength concrete (HSC) and strengthened by UHPFRC to improve shear and flexural behaviour. Series 2 includes a further twelve (12) doubly-reinforced beams/columns built with normal-strength concrete (NSC), and strengthened by UHPFRC to improve response under blast, or combined blast-axial loading. Various test parameters are examined including the effects of varying retrofit types (full jacket, U-jacket or T-sided), surface roughening methods, longitudinal steel reinforcement ratio, single vs. repeated blasts, and the effects of axial loading. The results from this thesis are presented in six journal articles. Papers 1 and 2 study the effects of UHPFRC jacketing on the static and blast behaviour of the singly-reinforced HSC beams in Series 1, while Paper 3 discusses the effects of additional parameters such as: the effect of retrofit type, roughening method and steel detailing on blast behaviour. Under static loading (Paper 1), the UHPFRC jacketing was found to be effective in increasing shear resistance (by preventing shear failure), and improving flexural behaviour (by increasing strength, stiffness, ductility and overall toughness) when compared to control beams built without UHPFRC. Similarly, under blast loads (Paper 2) the use of UHPFRC jacketing prevented shear failure, and improved flexural behaviour by reducing displacements at equivalent blasts, increasing overall blast capacity, and improving damage tolerance. On the other hand, the results show that UHPFRC-retrofitted beams with low longitudinal steel ratios may be vulnerable to brittle bar fracture failures. As part of the numerical research, finite element (FE) modelling is used to predict the static and blast behaviour of the test beams using software LS-DYNA (Papers 1 and 2). The results from Paper 3, provide further insights into the effects of retrofit type (FJ, UJ and T) and roughening method on blast performance; both the UJ and FJ retrofits were found to be effective in increasing shear resistance, reducing blast-displacements and increasing blast capacity, while the benefit of the T-sided retrofit was limited by the crushing capacity of HSC concrete. The effect of roughening method was found to be negligible, except at the very late stages of blast loading. Papers 4, 5 and 6 present the experimental results from the doubly-reinforced NSC beams tested in Series 2, with a focus on the effect of UHPFRC jacketing, UHPFRC retrofitting type and Axial loading, respectively. Paper 4 shows that the UHPFRC jacketing increased the stiffness and strength of the beams under both static and blast loading, however the high bond capacity of the UHPFRC and relatively low tension steel ratio increased the vulnerability of bar rupture failure. The numerical parametric study investigates the effects of steel ratio and blast load scenario, jacket thickness and interface location on blast performance and failure model. Paper 5 confirms that the blast performance of the beams is influenced by the retrofit type, with optimal performance obtained when using full- or U-jacketing. The efficient use of localized "hinge" retrofits was also found to be effective, and reduced the vulnerability to bar rupture. The numerical parametric study investigates the effects of steel ratio and blast load scenario (single vs. repeated) on the blast performance of the beams. Paper 6, studies the effect of UHPFRC jacketing in columns tested under combined axial and blast loading. The retrofit is shown to increase blast capacity and reduce blast-induced displacements and damage, though the final failure of the columns was governed by bar rupture. As part of the numerical parametric study the effects of axial load ratio, boundary conditions, steel ratio, jacket thickness and jacket design are studied numerically and found to have significant effects on blast behaviour and failure mode.

Phylogenetic research on non-model organisms has been hindered by limited marker availability. Next generation sequencing techniques are eliminating that barrier. Using Illumina sequencing technology, Trinity assembly software, custom Perl reciprocal BLAST scripts, and Primer3 primer prediction software, we produced and analyzed 7 Plecopteran transcriptomes, representing 7 of the 16 total families, in an attempt to identify and develop conserved orthologous genetic markers. The transcriptomes were used to reconstruct a gene content phylogeny using a simple distance matrix generated from reciprocal blastn data. By producing and filtering a reciprocal blast network we identified and aligned over 450 putative orthologs. Out of these, 25 primer pairs were selected that showed 100% conserved primer sites across all the transcripts from which they were created. Of those 25, 3 loci (PlecSK1, Perl534, and PvC2190) show very positive phylogenetic potential. These 3 markers may also be suitable and even highly useful in population genetic studies in which the populations have had sufficient time to develop significant genetic separation. The rapid and affordable nature of this study demonstrates the ease by which non-model organism phylogenetics can be expanded and made more robust.

Blast-induced traumatic brain injury and hearing loss are two of the most common forms of the “invisible wounds of war” resulting from the United States’ Global War on Terror. Several published studies have been confirming recent reports from VA healthcare centers of blast-exposed Service Members complaining of auditory problems despite having hearing that is, for all intents and purposes, normal. Most common among these complaints is problems understanding speech in crowded and noisy situations. We hypothesized that problems with speech comprehension could either be the result of 1) damage to sensory areas in the auditory periphery or 2) blast-induced traumatic brain injury (TBI) to cortical networks associated with the processing of attention, memory, and other executive functions related to the processing of speech and linguistic information. In Chapter 1 of this thesis, we found that in a population of blast-exposed Veteran Service Members, problems with speech comprehension in noise were due to cognitive deficits likely resulting from issues related to their post-traumatic stress disorder (PTSD) diagnoses. Chapter 2 takes and expanded look at the topics of Chapter 1 with a more comprehensive battery of audiological, electrophysiological, and neuropsychological tests in active duty Service Members with and without a history of blast exposure. Unlike in veterans with PTSD, we found subclinical levels of peripheral auditory dysfunction, as well as evidence of compromised neural processing speed in the blast-exposed group. These deficits were also consistent with poorer performance on a standardized speech-in-noise test and lower self-reported ratings on an abbreviated version of the Speech, Spatial, and Qualities (SSQ) of Hearing questionnaire (Gatehouse and Noble, 2004). In Chapter 3,we modeled outcomes from the SSQ survey using objective measures of hearing function related to audibility, distortion of the neural representation of sound, attention, age, and blast status. We found for all subjects age and high frequency hearing thresholds predicted survey outcomes related to everyday listening ability. Within non-blast controls, however, measures of attention could differentiate between good and exceptional listening ability. Results from blast exposed subjects remained inconclusive. Collectively, these findings highlight the need for audiologists to take into account more than audiometric measures alone when diagnosing and treating hearing dysfunction in this unique and specialized patient population.

Polyurethane resin injection is a treatment being considered as a replacement for traditional methods of ground improvement. It has been used to re-level foundations and concrete slabs that have settled over time. Additional claimed benefits of the treatment have been noted recently, including improved factors of safety against soil liquefaction and reduced earthquake-induced settlements. To investigate the capability of the polyurethane resin injection treatment to mitigate liquefaction, two full-scale blast liquefaction tests were performed; one test was conducted in an improved panel (IP), an 8 m circular area treated with the polyurethane resin in a 1.2 m triangular grid from a depth of 1 to 6 m, and another test in an untreated 8 m circular area, the natural panel (NP). Each blast test was severe enough to produce liquefaction (ru ≈1.0) in the respective panel, with blast-induced settlements in the range of 70 to 80 mm. Despite similar levels of ground-surface settlement in the IP and NP, settlement within the top 6 m of the IP was about half that of the NP. A CPT-based predicted settlement for each panel was employed using the Zhang et al. (2002) methodology. Good correlation was found between the observed settlements and predicted settlements in both panels. Differential settlements across the panels were calculated based on ground-based lidar surveys, with a reduction of 42 to 49% between the IP and NP. The measured total and differential settlements following resin injection were at the bottom of the range observed in blast tests on a variety of shallow ground improvement methods conducted by the New Zealand Earthquake Commission in 2013. The persistence of the polyurethane resin injection ground improvement three years following its installation was indicated by the lasting increase of fundamental in situ test parameters. The results of the study indicate that resin injection is a viable method of ground improvement to reduce liquefaction-induced settlements by creating a stiffer surficial crust.

The main objectives of this study were to investigate (i) anovel wetland treatment technology and (ii) selected bed filtermedia for the removal of contaminants from landfill leachate. Areview of the literature concerning experiences of the use ofconstructed wetlands (CW) for the removal of nitrogen fromlandfill leachate, showed that at least three groups oftreatment systems are in practice: sub-surface flow wetlands,hybrid systems (a combination of vertical and horizontal flowwetlands) and, compact constructed wetland (CCW). Most of thesetypeswere generally effective in reducing nitrogen (N,e.g.NH4-N, dominant N species in leachate) down toeffluent concentrations of about 10 mg L-1. Unfortunately, very little evidence ofresponsible mechanisms for the removal of N was presented,although some data indicated denitrification. The treatmentperformance of a compact constructed wetland (CCW) applied atthe Tveta Landfill, Södertälje, Sweden, wasevaluated. Chemically purified leachate and untreated leachatewere applied in periods of 7 day submergence and 7 day drainageto different sections of the CCW. The removal efficiency variedbetween 40 and 82%, and a mass removal rate of up to 5.1 g m2d-1was achieved. The chemical pre-treatment had adecisive role for the highest removal efficiencies obtained andit was unclear whether that treatment enhanced the efficiencybecause of lower toxicity and/or content of fewer competingcations. The possible combination of bed filter media and CCWas an ecotechnological treatment method for landfill leachatewas investigated by bench-scale laboratory column experiments.Reactive filter media (sorbents) was selected from their knownor suggested capacities for removal of heavy metals, nitrogenand phosphorus. Quartz sand or natural sand from an esker wasused as reference medium. Peat was used as an additionalcomponent in mixtures with the reactive media Polonite®(product from the bedrock opoka) and blastfurnace slag (BFS). A small column study also involved zeolite.Phosphorus was efficiently removed by Polonite®and NH4-N to some extent. Concerning metal removal, thebest performance was found as well for Polonite®, especially for Mn, Fe, Zn and Cu. The BFSshowed good removal efficiency for Cu, Ni and Mo. The removalof different elements was suggested to be a combination ofseveral factors,e.g.precipitation, ion exchange and adsorption. Priorto full-scale application of reactive filters at a landfillsite, matrix selection, filter design and operationalprocedures must be developed. Keywords:Blast furnace slag; Compact constructedwetland; Metals; Nitrogen; Polonite; Sorbents