{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/127239"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/127239","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Theoretical and numerical framework for extrusion-based additive manufacturing applications","abstract":"Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2025-03-28 without embargo terms","abstract_html":"Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2025-03-28 without embargo terms","abstract_has_math":false,"creators":["Anugraha Wijaya, Ignasius Pradipta"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Civil Engineering","degree_department":null,"school":null,"contributors":["Masud, Arif","Lopez-Pamies, Oscar","Duarte, C. Armando","Geubelle, Philippe H"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2024,"date_issued":"2024-12-05","date_published":"2024-12-05","updated_at":"2026-07-22T22:25:03Z","subjects":["Additive Manufacturing","Constitutive Models","Evolving Materials","Inelastic Strain","Finite Deformation","Concrete Printing","Frontal Polymerization"],"languages":["en","eng"],"rights":["Copyright 2024 Ignasius Pradipta Anugraha Wijaya"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/2142/127239","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Masud, Arif","Lopez-Pamies, Oscar","Duarte, C. Armando","Geubelle, Philippe H"]},{"key":"dc:creator","label":"Author","values":["Anugraha Wijaya, Ignasius Pradipta"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2024-12-05","2024-12"]},{"key":"dc:type","label":"Dc Type","values":["text","Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Civil Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Additive Manufacturing","Constitutive Models","Evolving Materials","Inelastic Strain","Finite Deformation","Concrete Printing","Frontal Polymerization"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en","eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2024 Ignasius Pradipta Anugraha Wijaya"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://hdl.handle.net/2142/127239"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2025-03-28 without embargo terms","The student, Ignasius Pradipta Anugraha Wijaya, accepted the attached license on 2024-12-05 at 01:15.","The student, Ignasius Pradipta Anugraha Wijaya, submitted this Dissertation for approval on 2024-12-05 at 01:59.","This Dissertation was approved for publication on 2024-12-05 at 17:44.","DSpace SAF Submission Ingestion Package generated from Vireo submission #21427 on 2025-03-28 at 14:27:25","The main challenge in extrusion-based additive manufacturing (EB-AM) is synchronizing the parameters controlling the manufacturing process with the timescale of material evolution to ensure structural integrity during manufacturing. In their initial stage, the stiffness of EB-AM materials is relatively low, and therefore, the structure can undergo significant deformation and even failure while being manufactured. This work presents a theoretical and numerical framework that integrates the process parameters with material evolution in a unified way to model EB-AM processes. The significant contributions in this work are: (i) thermodynamically consistent constitutive models for evolving materials under loading, (ii) modeling the process of sequential material placement in EB-AM, and (iii) modeling viscoelastic materials with arbitrary compressibility in the context of finite strain theory. An important contribution in this work is the use of second law of thermodynamics to show the existence of inelastic processes in evolution of stiffening materials. An internal variable formalism is employed to model the inelastic strain associated with material evolution, and the corresponding evolution equation is derived. Then, a novel method to model the material placement in EB-AM is proposed. The method can accommodate various type of constitutive models, and can be easily implemented in existing finite element codes. The numerical models are validated via comparison with experimental data. Another important contribution is the treatment of evolving material compressibility. Commonly used materials in EB-AM, such as polymer and concrete, can feature a wide range of compressibility. At the start of the curing process, these materials are nearly incompressible, but can become compressible as they cure. Therefore, it is desirable to have a unified formulation that applies to materials with arbitrary compressibility. Starting from a compressible model, a displacement-pressure formulation is derived via Legendre transform in the context of finite viscoelasticity. Then, a stabilized finite element method based on variational multiscale method is developed to solve the resulting mixed initial-boundary-value problem. In addition, a novel time integration scheme is introduced to convert any explicit or implicit scheme into a stable scheme that preserves the determinant of the integrand. The proposed framework is employed in various settings such as contact-friction and thermo-chemo-mechanical problems. Applications of the framework to model concrete printing and frontal polymerization are presented."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Theoretical and numerical framework for extrusion-based additive manufacturing applications"]}]}],"canonical_facts":{"dc:contributor":["Masud, Arif","Lopez-Pamies, Oscar","Duarte, C. Armando","Geubelle, Philippe H"],"dc:creator":["Anugraha Wijaya, Ignasius Pradipta"],"dc:date":["2024-12-05","2024-12"],"dc:description":["Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2025-03-28 without embargo terms","The student, Ignasius Pradipta Anugraha Wijaya, accepted the attached license on 2024-12-05 at 01:15.","The student, Ignasius Pradipta Anugraha Wijaya, submitted this Dissertation for approval on 2024-12-05 at 01:59.","This Dissertation was approved for publication on 2024-12-05 at 17:44.","DSpace SAF Submission Ingestion Package generated from Vireo submission #21427 on 2025-03-28 at 14:27:25","The main challenge in extrusion-based additive manufacturing (EB-AM) is synchronizing the parameters controlling the manufacturing process with the timescale of material evolution to ensure structural integrity during manufacturing. In their initial stage, the stiffness of EB-AM materials is relatively low, and therefore, the structure can undergo significant deformation and even failure while being manufactured. This work presents a theoretical and numerical framework that integrates the process parameters with material evolution in a unified way to model EB-AM processes. The significant contributions in this work are: (i) thermodynamically consistent constitutive models for evolving materials under loading, (ii) modeling the process of sequential material placement in EB-AM, and (iii) modeling viscoelastic materials with arbitrary compressibility in the context of finite strain theory. An important contribution in this work is the use of second law of thermodynamics to show the existence of inelastic processes in evolution of stiffening materials. An internal variable formalism is employed to model the inelastic strain associated with material evolution, and the corresponding evolution equation is derived. Then, a novel method to model the material placement in EB-AM is proposed. The method can accommodate various type of constitutive models, and can be easily implemented in existing finite element codes. The numerical models are validated via comparison with experimental data. Another important contribution is the treatment of evolving material compressibility. Commonly used materials in EB-AM, such as polymer and concrete, can feature a wide range of compressibility. At the start of the curing process, these materials are nearly incompressible, but can become compressible as they cure. Therefore, it is desirable to have a unified formulation that applies to materials with arbitrary compressibility. Starting from a compressible model, a displacement-pressure formulation is derived via Legendre transform in the context of finite viscoelasticity. Then, a stabilized finite element method based on variational multiscale method is developed to solve the resulting mixed initial-boundary-value problem. In addition, a novel time integration scheme is introduced to convert any explicit or implicit scheme into a stable scheme that preserves the determinant of the integrand. The proposed framework is employed in various settings such as contact-friction and thermo-chemo-mechanical problems. Applications of the framework to model concrete printing and frontal polymerization are presented."],"dc:format":["application/pdf"],"dc:identifier":["https://hdl.handle.net/2142/127239"],"dc:language":["en","eng"],"dc:rights":["Copyright 2024 Ignasius Pradipta Anugraha Wijaya"],"dc:subject":["Additive Manufacturing","Constitutive Models","Evolving Materials","Inelastic Strain","Finite Deformation","Concrete Printing","Frontal Polymerization"],"dc:title":["Theoretical and numerical framework for extrusion-based additive manufacturing applications"],"dc:type":["text","Thesis"],"thesis:degree_discipline":["Civil Engineering"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:03Z"}