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EAS Doctoral Proposal Defense by Danilo Gianni Zeppilli Date: Monday, August 22, 2022 Time: 10:00 a.m. Topic: The Behavior of Crushable Problematic Calcareous and Glauconitic Soils Zoom Teleconference: https://umassd.zoom.us/j/92794428421?pwd=M20vYnBaWGREOFJZNUx2RkJWNXRMUT09 Abstract: Soil is primarily composed of solid particles created by weathering, but commonly found in our coastal zones are soils which are made of particles with internal voids created by biologic influence. Two soils of such nature are Calcareous and Glauconitic marine sediments. Calcareous soils are made of Calcium Carbonate and are formed when biologic organisms in the ocean such as foraminifera, algae, coral, and mollusks die and discard their shells or tests or through precipitation which then make its way to the ocean floor. Due to their hollow nature these sediments have various densities depending on their particle size while sand-sized particles have lower densities than fine-grained particles. Glauconitic soils are made of iron and potassium, have internal cracks and fissures, and begin forming in marine and estuarine environments at the water-soil boundary. These two types of soils are fragile and brittle in nature due to their internal voids and can lead to many problematic behaviors during construction. When calcareous soils are loaded through pile driving and foundation construction, pile running, and increased compressibility are expected responses that must be carefully considered. Where glauconite soils are concerned particle breakage leads to pile driving resistance and decreases in bearing capacity as well as adhesion to piles upon their removal. This proposed dissertation research aims to investigate properties of these two problematic soils and determine the mechanisms behind their concerning responses. The first chapter of this proposed research will investigate the crushing of sands containing voids within the particles and the trends of void ratio and particle size evolutions during compression. This chapter aims to determine differences between hollow and solid soil crushing. The second chapter will look at the differences in specific gravity, particle sizes, plasticity, and shearing behaviors between uncrushed and crushed glauconitic soils. This will aid in insight on classifying these soils and their behaviors during pile driving and loading. Chapter three will look at differences in the transitional fines content (TFC) of a soil which has a variation in density between coarse- and fine- grained particles through hydraulic and compressive behavior. The TFC of typical soils is around 30% fine grained particle, and it is suspected that when the fines portion has a higher specific gravity, this content will be lower. Finally, the fourth chapter will investigate the triaxial compression of a sand containing hollow fragile particles. This chapter will utilize X-Ray micro computed tomography (CT) to track the compression and crushing of hollow particles when consolidation and shear compression occurs. Through these four chapters, the mechanical responses of several brittle and crushable soils which contain internal void space will be investigated to aid in determining classification of these problematic soils. ADVISOR(S): Dr. Ryan Beemer, Department of Civil and Environmental Engineering (rbeemer@umassd.edu, 508.999.8416) COMMITTEE MEMBERS: Dr. Daniel MacDonald, Civil and Environmental Engineering Dr. Walaa Mogawer, Civil and Environmental Engineering Dr. Cynthia Pilskaln, SMAST/Estuarine & Ocean Sciences Dr. Santiago Quinteros, Norwegian Geotechnical Institute NOTE: All EAS Students are ENCOURAGED to attend.

Mechanical Engineering MS Thesis Defense by Mr. Ayomikun Adebanjo DATE: August 29, 2022 TIME: 11:00 a.m. 1:00 p.m. LOCATION: ZOOM: https://umassd.zoom.us/j/98983538979 Meeting ID: 989 8353 8979 Passcode: 228816 TOPIC: Numerical Modeling of the Thermal History of Livers During Cryopreservation ABSTRACT: The current standard method for organ preservation is Static Cold Storage (SCS) which allows for preservation times of up to 12-16 hours for livers. This time constraint limits the availability of donor organs for transplantation which is the only cure for end-stage organ failure. Different techniques are being studied for their potential to improve preservation times, and the most promising is cryopreservation. This method involves freezing a biological material to subzero temperatures where metabolic functions are completely halted without significantly affecting its viability when thawed. Mathematical modeling of the thermal history during this procedure can provide better insight into the injury mechanisms that occur during this process and help to improve cryopreservation techniques. The goal of this work was to create a numerical model to predict the freezing profile of a liver perfused with a cryoprotective agent (CPA). A one-dimensional (1-D) finite difference scheme was developed, and the enthalpy method was used to account for the phase change process. The model was used to predict the thermal profiles for freezing experiments of rat livers loaded with different solutions. The results showed that the rat livers perfused with the University of Wisconsin (UW) solution behaved differently compared to the ones loaded with the UW + 12% Propylene Glycol (PG) solution, as the UW + 12% PG solution has a lower freezing point and undergoes binary freezing. The temperature profiles for rat liver thawing experiments were also modeled. The results showed that the numerical model was not able to successfully capture the temperature gradient within the liver shown by the experimental data, and further investigation needs to be carried out to incorporate the missing thermal resistance effect into the model. This work gives new insight into the freezing behavior of livers loaded with a binary solution, and there is potential to improve the modeling capabilities of this numerical scheme, including scaling up to multiple dimensions and incorporating mass transfer (water transport) effects into the model. ADVISORS: -Dr. Sankha Bhowmick, Professor of Mechanical Engineering, UMassD -Dr. Mehdi Raessi, Associate Professor of Mechanical Engineering, UMassD COMMITTEE MEMBERS: Dr. Hangjian Ling, Assistant Professor of Mechanical Engineering, UMassD Open to the public. All MNE students are encouraged to attend. For more information, please contact Dr. Sankha Bhowmick (sbhowmick@umassd.edu). Thank you, Sue Cunha, Administrative Assistant UMass Dartmouth Mechanical Engineering Department scunha@umassd.edu 508-999-8492

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