title: President’s address 2012

authors: Rowarth, Jacqueline S.

abstract: The conferences, symposia and newsletters that we create are part of the information flow, and are driven by members. The role of NZGA is to assist in improving performance in all aspects of agrifood production. It is the interaction between farmers, researchers, policy analysts and industry personnel that leads to the development of new ideas and resource efficient thinking that makes a difference. That difference will allow New Zealand to have a role in feeding the world through sustainable agricultural production systems. The research and development, technology transfer and farm-enterprise resilience that we have already recognised as being vital for improving agricultural productivity have been highlighted as being vital for the world.

text: President’s address 2012 The conferences, symposia and newsletters that we create are part of the information flow, and are driven by members. The role of NZGA is to assist in improving performance in all aspects of agrifood production. It is the interaction between farmers, researchers, policy analysts and industry personnel that leads to the development of new ideas and resource efficient thinking that makes a difference. That difference will allow New Zealand to have a role in feeding the world through sustainable agricultural production systems. The research and development, technology transfer and farm-enterprise resilience that we have already recognised as being vital for improving agricultural productivity have been highlighted as being vital for the world.

year: 2012

title: An improved and robust finite element model for simulation of  cold-formed steel built-up beams

authors: Birwadkar, Harsh Hemant

subjects: Cold-formed steel

abstract: Cold-formed steel (CFS) built-up sections are increasingly utilized in structural applications due to their lightweight properties, high strength-to-weight ratio, and enhanced moment capacity, which can be further improved by adding stiffeners to the webs or flanges. Accurately determining the moment capacity of these sections is important for practical use. This can be achieved through experimental testing or finite element analysis (FEA) using a four-point bending setup. However, conducting full-scale experimental tests is both expensive and time-consuming, and developing a full-scale finite element (FE) model to replicate these tests can be computationally intensive. 

To address these challenges, this study introduces an accurate, efficient, and robust numerical method that replicates the behaviour of CFS built-up sections, applicable to both back-to-back and face-to-face configurations. The proposed numerical methodology demonstrates excellent agreement with available test results in terms of moment capacity and failure modes, highlighting its potential for determining the moment capacity of built-up sections. The study further investigates two cross-sectional types—stiffened nested and unstiffened nested—to evaluate their behaviour and moment capacity. 

The proposed simplified model was subsequently used in an extensive parametric study to determine the moment capacity of stiffened and unstiffened nested sections. Parameters considered in the study include varying section thicknesses (0.75 mm to 3.00 mm), web depths (150 mm to 600 mm), section configurations (nested and stiffened nested), and screw spacings (75 mm, 150 mm, and 300 mm). Given that existing design standards, such as those from the American Iron and Steel Institute (AISI 2016) and the Australian/New Zealand Standards (AS/NZS 2018), lack specific guidelines for calculating the moment capacity of these sections, this research aims to fill that gap. Furthermore, to simulate practical scenarios, models incorporating screws in the webs (screw-web model) were developed and compared against the simplified model. The results of the parametric study revealed that the moment capacity of the built-up sections is significantly influenced by section thickness, web depth, and section configuration. Screw spacing, however, had a less significant impact. Notably, the moment capacity of the screw-web model was lower than that of the simplified model, emphasizing the importance of bimoment and warping deformation in connection design. 

The study concludes that the developed simplified model provides a computationally efficient tool for predicting the moment capacity of built-up beams, offering valuable insights for designers and engineers. Additionally, the nested section configuration is recommended for achieving higher moment capacity compared to the stiffened nested section.

text: An improved and robust finite element model for simulation of  cold-formed steel built-up beams Cold-formed steel (CFS) built-up sections are increasingly utilized in structural applications due to their lightweight properties, high strength-to-weight ratio, and enhanced moment capacity, which can be further improved by adding stiffeners to the webs or flanges. Accurately determining the moment capacity of these sections is important for practical use. This can be achieved through experimental testing or finite element analysis (FEA) using a four-point bending setup. However, conducting full-scale experimental tests is both expensive and time-consuming, and developing a full-scale finite element (FE) model to replicate these tests can be computationally intensive. 

To address these challenges, this study introduces an accurate, efficient, and robust numerical method that replicates the behaviour of CFS built-up sections, applicable to both back-to-back and face-to-face configurations. The proposed numerical methodology demonstrates excellent agreement with available test results in terms of moment capacity and failure modes, highlighting its potential for determining the moment capacity of built-up sections. The study further investigates two cross-sectional types—stiffened nested and unstiffened nested—to evaluate their behaviour and moment capacity. 

The proposed simplified model was subsequently used in an extensive parametric study to determine the moment capacity of stiffened and unstiffened nested sections. Parameters considered in the study include varying section thicknesses (0.75 mm to 3.00 mm), web depths (150 mm to 600 mm), section configurations (nested and stiffened nested), and screw spacings (75 mm, 150 mm, and 300 mm). Given that existing design standards, such as those from the American Iron and Steel Institute (AISI 2016) and the Australian/New Zealand Standards (AS/NZS 2018), lack specific guidelines for calculating the moment capacity of these sections, this research aims to fill that gap. Furthermore, to simulate practical scenarios, models incorporating screws in the webs (screw-web model) were developed and compared against the simplified model. The results of the parametric study revealed that the moment capacity of the built-up sections is significantly influenced by section thickness, web depth, and section configuration. Screw spacing, however, had a less significant impact. Notably, the moment capacity of the screw-web model was lower than that of the simplified model, emphasizing the importance of bimoment and warping deformation in connection design. 

The study concludes that the developed simplified model provides a computationally efficient tool for predicting the moment capacity of built-up beams, offering valuable insights for designers and engineers. Additionally, the nested section configuration is recommended for achieving higher moment capacity compared to the stiffened nested section.

year: 2024

title: Te Awa Atua, Te Awa Tapu, Te Awa Wahine: An examination of stories, ceremonies and practices regarding menstruation in the pre-colonial Māori world.

authors: Murphy, Ngahuia Aroha Grace

subjects: mana wahine

abstract: This thesis examines Māori cosmological stories, ceremonies, and traditional practices regarding menstruation in pre-colonial Māori society. I use kaupapa Māori and mana wahine as a theoretical and methodological framework, contextualising these stories within Māori cultural paradigms.This is important because menstruation has been framed within deeply misogynist, colonial ideologies in some ethnographic accounts, distorting menstrual rites and practices beyond recognition. These interpretations have been used to inform colonialist narratives of female inferiority in traditional Māori society, attempting to change Native constructs of womanhood. Such narratives have been perpetuated in contemporary literature, reinforcing powerful discourses of menstrual pollution and female inferiority. This thesis is a challenge to such representations. By examining menstrual stories located in Māori cosmologies, and investigating tribal histories, oral literatures, ceremonies and rites, I argue that menstruation was seen as a medium of whakapapa (genealogy) that connected Māori women to our pantheon of atua (supernatural beings). A study of ancient menstrual rites, recorded in tribal songs and chants, reveal that menstrual blood was used for psychic and spiritual protection. These examples unveil striking Indigenous constructs of womanhood that transform colonialist interpretations and radically challenge notions of female inferiority and menstrual pollution. I maintain in this thesis that presenting menstruation and menstrual blood as putrid is a politically motivated act of colonial violence that specifically targets the source of our continuity as Indigenous People, the whare tangata (house of humanity – womb of women). I pose the question ‘if menstrual blood symbolises whakapapa, what does it mean to present it as ‘unclean’ and how do such representations cut across the politics of tino rangatiratanga (autonomy)?’ Through in-depth semi-structured interviews, kōrero (dialogue), and wānanga (series of conversations) with Māori women, including cultural experts, scholars, artists, and mana wahine exponents, I gather a collection of ceremonies, stories, and wisdoms that reclaim Māori spiritualities which celebrate menstruation as divine. Within the context of a colonial history of marginalisation, this work is an activist site of political resistance which takes a step towards re-threading the feminine strands in the spiritual fabric of our world, torn asunder by the ideological imposition of a colonial, Christian male god. I argue, that menstruation is a potent site of decolonisation, cultural reclamation, and resistance toward the perpetuation of colonial hegemony.

text: Te Awa Atua, Te Awa Tapu, Te Awa Wahine: An examination of stories, ceremonies and practices regarding menstruation in the pre-colonial Māori world. This thesis examines Māori cosmological stories, ceremonies, and traditional practices regarding menstruation in pre-colonial Māori society. I use kaupapa Māori and mana wahine as a theoretical and methodological framework, contextualising these stories within Māori cultural paradigms.This is important because menstruation has been framed within deeply misogynist, colonial ideologies in some ethnographic accounts, distorting menstrual rites and practices beyond recognition. These interpretations have been used to inform colonialist narratives of female inferiority in traditional Māori society, attempting to change Native constructs of womanhood. Such narratives have been perpetuated in contemporary literature, reinforcing powerful discourses of menstrual pollution and female inferiority. This thesis is a challenge to such representations. By examining menstrual stories located in Māori cosmologies, and investigating tribal histories, oral literatures, ceremonies and rites, I argue that menstruation was seen as a medium of whakapapa (genealogy) that connected Māori women to our pantheon of atua (supernatural beings). A study of ancient menstrual rites, recorded in tribal songs and chants, reveal that menstrual blood was used for psychic and spiritual protection. These examples unveil striking Indigenous constructs of womanhood that transform colonialist interpretations and radically challenge notions of female inferiority and menstrual pollution. I maintain in this thesis that presenting menstruation and menstrual blood as putrid is a politically motivated act of colonial violence that specifically targets the source of our continuity as Indigenous People, the whare tangata (house of humanity – womb of women). I pose the question ‘if menstrual blood symbolises whakapapa, what does it mean to present it as ‘unclean’ and how do such representations cut across the politics of tino rangatiratanga (autonomy)?’ Through in-depth semi-structured interviews, kōrero (dialogue), and wānanga (series of conversations) with Māori women, including cultural experts, scholars, artists, and mana wahine exponents, I gather a collection of ceremonies, stories, and wisdoms that reclaim Māori spiritualities which celebrate menstruation as divine. Within the context of a colonial history of marginalisation, this work is an activist site of political resistance which takes a step towards re-threading the feminine strands in the spiritual fabric of our world, torn asunder by the ideological imposition of a colonial, Christian male god. I argue, that menstruation is a potent site of decolonisation, cultural reclamation, and resistance toward the perpetuation of colonial hegemony.

year: 2011