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Development of a novel Fibre-Reinforced Polymer (FRP) wall panel system for thermally efficient residential construction in New Zealand
(The University of Waikato, 2025) Feng, Chong; Fang, Zhiyuan (Arthur); Lim, James Boon Piang; Duke, Mike
This thesis investigates the viability of a novel Fibre Reinforced Polymer (FRP) wall panel system as an alternative to conventional lightweight timber-framed construction for residential buildings in New Zealand. This study is motivated by the widening gap between the thermal performance assumed at the building consent stage and the significantly lower as-built performance delivered by traditional timber-framed envelopes. Despite the existing insulation requirements under the New Zealand Building Code, timber-framed walls routinely fail to meet the minimum thermal thresholds because of systemic thermal bridging, discontinuous insulation, and high framing percentages arising from structural, weathertightness, and regulatory constraints. These factors collectively undermine compliance with Clauses H1 (Energy Efficiency) and E3 (Internal Moisture), indicating the need for alternative construction systems capable of delivering verifiable thermal performance. The FRP wall panel system evaluated in this study was first implemented in two full-scale duplex dwellings (the case-study building) completed in Hamilton in 2024, providing an opportunity for a comprehensive structural and thermal assessment. The system comprises factory-produced FRP composite panels with integrated phenolic foam insulation, tongue-and-groove joints, and a cavity air layer, yielding an inherently continuous thermal envelope. A multi-method research framework was employed, integrating (1) a comparative literature review, (2) NZS 4214 isothermal-planes thermal-bridging analysis, (3) laboratory thermal conductivity testing, (4) BRANZ P21 structural verification of wall and lintel specimens, and (5) in-field heat-flux and U-value monitoring undertaken in both summer and spring across two units of the case-study building. The experimental results confirmed that the FRP wall panel system exhibited markedly reduced thermal bridging compared to timber framing. Laboratory characterisation established an FRP skin thermal conductivity of 0.248 W/m·K, enabling accurate construction-level thermal resistance (R-value) calculation. When applying NZS 4214 isothermal planes method, the FRP wall panel system achieved a conservative construction R-value of R2.84 m²·K/W representing a 70.1% improvement over a typical timber-framed wall with a 30.95% framing fraction (R1.67), and a 77.5% improvement over a 34.12% framing fraction scenario (R1.60). These findings demonstrate that the FRP wall panel system comfortably exceeds the current H1/AS1 requirement of R2.0 for external walls without relying on the thermal-mitigation strategies required in timber framing. Structural testing further confirmed that the FRP walls and lintel configurations met or exceeded the NZBC Clause B1 performance when assessed against the AS/NZS 1170 load combinations and BRANZ P21 cyclic racking criteria. In-field monitoring corroborated the analytical results. Continuous heat flux measurements recorded stable in-situ U-values consistent with theoretical modelling, while cavity and indoor temperatures remained resilient to outdoor fluctuations. The system effectively mitigates localised thermal bridging at corners, junctions, and lintels, where timber-framed envelopes typically experience significant insulation discontinuities. The analysis produced 12 representative U-value measurements over different diurnal periods. The individual values ranged from 0.060 to 0.387 W/m²K, while the average U-value across the study period was 0.206 W/m²K with typical indoor and outdoor temperatures of 22 °C and 17 °C, respectively. When compared with the theoretically derived U-value of 0.352 W/m²K (equivalent to R2.84 m²·K/W), the in-field results show that, on average, the measured U-value was 41% lower than the theoretical value, corresponding to an in-situ R-value of approximately R4.85 m²·K/W, which is approximately 70.8% higher than the analytical R2.84 value. Collectively, these findings provide strong and defensible evidence that the FRP wall panel system offers a credible, high-performance alternative to conventional timber-framed construction. Through integrated structural and thermal functionality, the system addresses longstanding deficiencies associated with timber-framed envelopes, simplifies compliance pathways across Clauses H1, E2, and B1, and delivers a more thermally reliable building envelope under real New Zealand Zone 2 climatic conditions. Therefore, this study establishes the FRP wall panel system as a technically robust and practically viable construction methodology capable of supporting the delivery of warmer, drier, healthier, and more energy- efficient housing in New Zealand.
Low molecular weight cationic and anionic peptides from macromolecular aggregates in bovine seminal plasma and their effects on bull sperm
(The University of Waikato, 1994) Al-Somai, Niaz Mohamed Rashed; Molan, Peter C.
The detrimental effect of bovine seminal plasma on sperm is believed to be the action of its constituent proteins and peptides. The major proteins in seminal plasma are known to be aggregates of peptides of low molecular weight. Various researchers have reported that the anti-sperm activity in seminal plasma is spread over a wide range of molecular weights. High molecular weight cationic material from seminal plasma is believed to be more damaging to sperm than high molecular weight anionic material. The substance or substances responsible for the detrimental effect have not been fully characterised. The current study was undertaken to examine, more thoroughly, the detrimental effect of bovine seminal plasma on sperm, to isolate and characterise the component( s) of low molecular weight from the aggregate, and to study the interaction between these components with regard to the formation of aggregates and their effect on sperm motility. In order to achieve this goal, a method had to be developed to isolate the anti-sperm component(s), to give a better dissociation of the component(s) from the macromolecules and to disaggregate the macromolecules to their constituents. Preliminary investigation, using gel permeation chromatography, indicated that low molecular weight fractions from bovine seminal plasma were more detrimental to sperm motility than those of higher molecular weight. By dialysis in the presence of citrate or under acidic conditions followed by gel permeation chromatography under acidic conditions, the low molecular weight components were released from the aggregates and they were assessed for their detrimental effects on sperm. Although they were found to have more detrimental effect than the parent aggregate, they tended to reaggregate to higher molecular weights under neutral conditions. Methods evaluated as ways of achieving disaggregation were: dialysis in membranes with cut-off of various molecular weights; gel permeation chromatography under dissociating conditions; selective precipitation with isopropanol; immobilisation of the cationic proteins on a cation exchanger, with extensive washing with acetonitrile at pH 3 to dissociate the anionic component(s), then elution with 0.01 mol/l NaOH; separation of the hydrophobic from the hydrophilic component(s) by immobilisation on a hydrophobic interaction column (Phenyl Superose); and reverse phase chromatography on FPLC columns to separate proteins and peptides. Further sequential use of these methods on FPLC columns for final purification resulted in the isolation of the anionic and cationic peptides in a reasonably homogenous form. All the fractions obtained using the above methods were assessed for their effects on sperm washed by centrifugation in Ficoll solution to free them from seminal plasma. The washed sperm were suspended in a defined diluent to provide a good test system for examining the effects of seminal plasma and its fraction on sperm. From attempts to isolate the damaging component from seminal plasma, it appeared that relatively high molecular weight cationic or anionic proteins retained anti-sperm activity while they were in aggregated form, however, the extent of activity depended on the form of aggregation. The isolated cationic peptide was highly basic in nature, highly active against sperm and failed to form an aggregate by itself under neutral pH. The isolated anionic peptide was hydrophobic in nature, inactive on sperm and failed to form an aggregate by itself. A combination of the active cationic and the inactive anionic peptide succeeded, in a certain ratio, in the formation of a large aggregate at neutral pH. This was demonstrated by a reaggregation study with radiolabelled anionic peptide which showed incorporation in aggregates which eluted at the high molecular weight region indicating that the two peptides were required for formation of aggregates. The combination of the two peptides reduced the detrimental effect of the active cationic peptide. It is hypothesised that the aggregates in seminal plasma are an assembly of the active cationic peptide with the inactive anionic peptide. This aggregation is a way of attenuating the damaging effect while the release of these low molecular weight from the large aggregates accentuates the damaging effects. The well established antibacterial activity in seminal plasma is highest in the form of high molecular weight aggregates. Aggregation in the form of high molecular weight components may serve to protect the male reproductive tract against bacterial invasion and protect the sperm from the toxic effect of the low molecular weight components by being in the form of high molecular weight aggregates.
A study of diversity in anaerobic cellulolytic thermophilic bacteria
(The University of Waikato, 1992) Rainey, F.A.; Morgan, Hugh W.; Janssen, Peter H.
Enrichments were set up using anaerobic bicarbonate buffered medium with cellulose and various other polysaccharides as the enrichment substrate. The inocula were water and sediment samples from freshwater and brackish thermal springs. These enrichments yielded anaerobic, cellulolytic, thermophilic bacteria with three distinct morphologies. Two of these isolates, a spirochete and a Thermotoga-like organism, were easily distinguished on the basis of their characteristic morphologies. The remaining isolates were rod-shaped and not easily distinguishable. The spirochete and the Thermotoga-like organism were fully characterised and their taxonomic position determined. The majority of the rod-shaped isolates had temperature optima of 70°C, in contrast to the previously described cellulolytic, thermophilic species of the genus Clostridium, which have temperature optima of 60-65°C. The degree of diversity within this group of rod-shaped bacteria and previously described isolates from various geographic locations was determined using three methods, numerical taxonomy, protein electrophoresis and phylogenetic analysis of the 16S ribosomal RNA. The results from these three studies showed the rod-shaped organisms to be a diverse group, not closely related to the cellulolytic, thermophilic members of the genus Clostridium. The phylogenetic study of representative isolates demonstrated this group of organisms to be a new sub-line of descent within the Clostridium/Bacillus subdivision of the gram positive bacteria. The results of this polyphasic approach allowed suggestions to be made as to the taxonomic position of these organisms. The isolation of the thermophilic spirochete and its designation to the genus Spirochaeta has extended the phenotypic and phylogenetic diversity of the organisms classified within the Spirochaetales. The phylogenetic study demonstrated the incoherence of the present taxonomy of the genus Spirochaeta. The Thermotoga-like isolate was shown to be a member of the genus Thermosipho on the basis of both phenotypic and phylogenetic characteristics. The isolation of this organism extended the geographical locations from which the members of the Thermotogales have been isolated.
User participation in the development of interorganisational systems and its effect on the success of such systems
(The University of Waikato, 1993) Cavaye, Angele L. M.; Cragg, Paul
This study focused on customer participation as one variable impacting on the adoption of systems which link organisations with their customers. The topic draws on literature concerning user participation in system development and, secondly, on literature relating to interorganisational and strategic systems. No previous research has focused on this research topic. Three related research questions were identified and investigated. The first question concerned antecedents which determine an organisation’s decision on whether or not to involve customers in the design and building of the system. The second question concerned the way in which customers participate in system development. The third question related to the effect of customer participation during development on adoption of the system. A multiple case approach was adopted for the empirical component of the study. Data was collected on 9 systems in New Zealand. Data analysis included within case analysis for each individual case and cross case analysis. It was found that customer participation during system design occurs in a minority of cases only and is associated with systems which are developed in response to customer initiatives or for competitive reasons. The effect of participation on subsequent adoption is indirect: participation can affect the ability of a system to fulfil a customer need and this need induces a customer to adopt the system. The study found that customer participation must be considered in relation to other adoption factors. A major outcome of the study is a model explaining and predicting adoption according to five adoption factors. If a system involves a customer in high acquisition costs, fast adoption is unlikely. The marketing effort by the sponsoring organisation and the technological awareness of the customer are strongly correlated with adoption.
Some aspects of the ecophysiology of Paulownia spp.
(The University of Waikato, 1993) Ede, Fiona Jean; Green, T.G. Allan; Silvester, Warwick B.
Members of the Paulownia genus have recently received widespread attention in New Zealand for their potential as special purpose timber trees and application in agroforestry systems. There has been only limited prior investigation of the ecophysiology of Paulownia. This study aimed to quantify aspects of gas exchange; biomass, nutrient and carbohydrate partitioning; and propagation and seedling establishment techniques in field grown and pot grown Paulownia trees, in Hamilton, New Zealand. Gas exchange measurements were undertaken using either a closed system LICOR 6200 unit or an open system Walz CMS 400 unit. Rates of gas exchange of Paulownia leaves under saturating light were high, with Aₘₐₓ in fully mature, non-senescent leaves ranging from 12 μmol m⁻² s⁻¹ to 25 μmol m⁻² s⁻¹, with gₛ between 0.2 mol m⁻² s and 0.8 mol m⁻² s⁻¹. The relationship between A and gₛ was variable which resulted in Cᵢ ranging from 190 μl 1⁻¹ to 280 μl 1⁻¹ under ambient CO₂ concentrations. High rates of transpiration were maintained in the large leaves to facilitate evaporative cooling under high radiation load. Leaf water potentials remained high throughout the day and, on the occasions when a midday depression of gas exchange rates was found, there was little evidence that it was a response to water stress. Circumstantial evidence suggested some form of negative feedback was involved in decreasing gas exchange rates in during the latter part of the day. Measurement of the ACᵢ response found low levels of stomatal limitation of photosynthesis, with l typically between 12% and 30%. The plants exhibited a number of characteristics of obligate sun plants, with the PPFDₛₐₜ of the leaves generally above 1000 μmol m⁻² s⁻¹. The pattern of biomass allocation, with a large proportion of the perennial tissues present as roots and the large investment in foliage, particularly in the establishment phase, was another feature typical of sun plants and enabled the plant to maintain a high growth rate. Growth rates were enhanced by the regular application of liquid fertilizer and frequent watering, and were higher in the warmer conditions of a glasshouse environment than outside. However, the temperature regime during leaf development had no effect on values of Aₘₐₓ. The temperature regime during growth did not affect the allocation of nutrients. In the field grown trees, the highest concentrations of all nutrients, except zinc, were found in the annual tissues, with foliar levels of nutrients in Paulownia similar to those reported for other timber species. Nitrogen levels in fully mature Paulownia leaves were generally between 2% and 2.5%, and within this range there was little correlation between nitrogen content and Aₘₐₓ. Nutrient levels in perennial tissues showed little change throughout each season, although nitrogen levels did increase in woody tissues at the end of each season. The levels of soluble sugars were high in all tissues of the Paulownia trees studied, in comparison with those found in other trees. The perennial root material stored large amounts of soluble sugars over the dormant season, with an average of 30% of the dry weight of the lateral roots found as soluble sugars at the last harvest of each season. The high soluble sugar content of these roots probably facilitated the growth of new root and shoot material when root cuttings were taken. The position of the root cutting in the parent root system had no effect on the regeneration capacity of the cutting. Cuttings with diameters less than 5 mm were less likely to regenerate than larger cuttings. Paulownia seedlings were found to suffer from transplant shock and generally grew more vigorously after transplanting if they were coppiced, rather than planted intact. Thus it was concluded that high rates of gas exchange and growth could be achieved by Paulownia trees if grown under conditions of high light, consistently warm temperatures, with frequent watering and the application of high rates of nutrients.