Axial Compression Behaviour Analysis of Insulated Concrete Form (ICF) Wall Panel with Fibre Cement Board

Nowadays, one of the fastest growing technique is an Insulated Concrete Form (ICF). It has advantages like cost-effective, less maintenance, soundproof, energy-efficient, waterproof and disaster-resistant. ICF wall panels are made by interlocking Fibre Cement Board (FCB) sheet which poured in placed concrete. In this study, the behaviour of the ICF wall panel under axial compression is examined with experimental and analytical methods. ICF wall panels cast with various thickness and dense FCB are tested under axial compression. ICF panels with 1.2gm3/cm dense FCB with changing width of 6mm and 10mm were casted for experimental analysis. The experiments were carried out in an universal testing machine with the capacity of 600 kN. The maximum peak load of 540 kN is observed in FCB of 10mm thick and the maximum displacement of 13mm is observed in FCB80 at the peak load. An analytical investigation is carried with Euler’s crippling load equation and an average variation of 12% is observed between analytical and experimental results. It is concluded that the ICF system of construction provides desirable plastic behaviour against axial compressive loading. Hence ICF is recommended for construction to get the maximum benefits of the wall while it reaches ultimate strain.

Bryophyte species and communities on various roofing materials, Estonia

Considering the recent growth of interest in using mosses in creating vegetated green roofs, we set the aim of our study to get an overview of the variety of moss and liverwort species and communities growing spontaneously on roofs. Data were collected from 67 roofs of five different types of materials: fibre cement, bitumen, stone, thatched and steel from Tallinn and rural areas on Hiiumaa Island and in South Estonia. Indicator species analysis, MRPP, cluster analysis and ordination methods (DCA, CCA) were used for data analysis. As a result of this research, generalist bryophytes occurring on all types of roofing materials were studied and bryophyte species characteristics for certain material types were identified. The thatched roofs differed most clearly from the other roof types in their species composition and had the highest species diversity. Stone and fibre cement roofs had similar species composition. The results revealed significant dependence of the composition of the bryophyte flora on roofs on the density of the bryophyte carpet formed over time on the roof and the presence of a tree canopy above the roof. Other important factors were roof relief, the height of the roof from the ground and the indicator of environmental pollution NOx. However, the studied roofs in Tallinn and rural areas did not show significant differences in the species composition of bryophytes. Five communities were delimited: (1) Syntrichia ruralis – Schistidium apocarpum; (2) Orthotrichum speciosum – Bryum argenteum; (3) Brachythecium rutabulum – Hypnum cupressiforme; (4) Ceratodon purpureus – Rhytidiadelphus squarrosus; and (5) Pleurozium schreberi – Dicranum scoparium. The mentioned communities inhabited locations that differed in environmental conditions. The findings of this research can help choose the roofing material and species suitable for a certain location in creating moss greenery on roofs.

Konka Board: a cement-pumice-tow sheathing board

Konka board was a New Zealand invention which combined cement, pumice and flax fibre ("tow") into a fibre-cement board, replacing the imported asbestos-cement sheet. Sold soon after manufacture, Konka, it could be nailed or screwed, and over time it hardened. A waterproof plain or stucco plaster finish provided a resilient, borer proof, fireproof, low maintenance house. Three patents created the Konka system – 34,845 for the fibre-reinforced board, 37,354 for the stud and support system into which a concrete grout was poured to lock the panels in place, and finally 52,50 for metal strips to ensure a smooth final plaster surface. A waterproofing additive in the plaster provided the final part of the system.The company quickly setup a national series of agents, with manufacturing ultimately occurring in Wanganui, Gisborne, Christchurch and Timaru. Patent 34,845 was challenged in 1927, with the Privy Council finding in 1930 that it was invalid, opening the way for similar products to be made. The development in the 1930s of NZSS 95 Model Building By-law allowed Konka to be used nationally, without further evidence as to its performance. However, competitor other products were also included e.g. Excell, Rotorua, Thermax, Duro, Wangan, Walasco and the asbestos based Fibrolite.Konka survived until the 1960s, when flax production was in decline, the high labour costs and manufacturing time meant it was no longer competitive. Even so, in a twist of fate it was a Konka style approach which led to cellulose fibre replacing asbestos in fibre-cement sheeting. In the twenty-first century, Konka could even be considered a desirable product – a natural fibre reinforced, composite sheet.

Making the New Zealand House 1792 – 1982

<p>A systematic investigation was undertaken of the techniques (materials and technologies) used to construct the shell of the New Zealand house (envelope and interior linings) between 1792 and 1982. Using census, manufacturing and import statistics with analysis of local and international archives and publications, principal techniques were selected and documented. A review of local construction and building publications provide a background to the development of construction education and training, as well as the speed of change. Analysis of census data showed that from 1858 to 1981 the majority of dwelling walls in terms of construction (appearance) were timber, brick, board or concrete, while the structure was timber frame. Analysis of import data for seven materials (galvanised iron, asbestos cement, cement, window glass, wood nails, gypsum and roofing slate) from 1870 to 1965 found the UK was a majority supplier until 1925, except for USA gypsum. For the rest of the period, the UK continued to play a preeminent role with increasing Australian imports and local manufacture. Examination of archival and published information on techniques used for the sub-floor, floor, wall (construction and structure), fenestration, roof and thermal insulation provide an overview of country of orign, decade of arrival, spread of use and, if relevant, reasons for failure. Forty materials (including earth and brick, stone, cement and concrete, timber and ferrous metals) and twenty-four technologies are documented. Revised dates of first NZ use are provided for eight of these e.g. the shift from balloon to platform framing occurred in the early 1880s rather than 1890s. Three case studies examine different aspects of the techniques (nails 1860 to 1965, hollow concrete blocks 1904 to 1910 and camerated concrete 1908 to 1920). The research shows that timber was the predominant structural (framing) material from 1792 to 1982. From the 1930s there was a shift away from timber construction (external appearance) to a wider range of products, including brick, board (asbestos- and more recently fibre-cement) and concrete. A new chronological classification of house development is proposed. These techniques travelled in a variety of ways and at speeds which indicate over this time New Zealand was technologically well connected and supported an innovative construction sector. The techniques covered are: Boards: asbestos, and cellulose fibre-cement, particle, plywood, pumice, softboard, and hardboard; Bricks: double and veneer; Building paper; Cement and lime: local and imported; Concrete: hollow block, monolithic, reinforced, Camerated, Oratonu and Pearse patents; Fired earth: bricks and terracotta roof tiles; Floors: concrete slab, suspended, and terrazzo; Framing: balloon, braced, light steel, and platform; Insulation: cork, fibreglass, macerated paper, perlite, pumice, foil, and mineral wool; Iron and Steel: cast and wrought iron, steel; Linings: fibrous plaster, plasterboard and wet; metal tile, shingles and slates; Nails: cut, hand-made, wire and plates; Piles: concrete, native timber and stone; Roof: strutted and truss rafter; Roofing: aluminium, corrugated iron, ; Sub-floor: vapour barrier, walls and ventilation; Timber: air and kiln drying, glulam, native, pit-saw and preservative treatments; Wall constructions: earth, log, slab, solid timber, raupo and stone; Weatherboards; and Windows: glass, aluminium, steel and timber frames.</p>

Making the New Zealand House 1792 – 1982

<p>A systematic investigation was undertaken of the techniques (materials and technologies) used to construct the shell of the New Zealand house (envelope and interior linings) between 1792 and 1982. Using census, manufacturing and import statistics with analysis of local and international archives and publications, principal techniques were selected and documented. A review of local construction and building publications provide a background to the development of construction education and training, as well as the speed of change. Analysis of census data showed that from 1858 to 1981 the majority of dwelling walls in terms of construction (appearance) were timber, brick, board or concrete, while the structure was timber frame. Analysis of import data for seven materials (galvanised iron, asbestos cement, cement, window glass, wood nails, gypsum and roofing slate) from 1870 to 1965 found the UK was a majority supplier until 1925, except for USA gypsum. For the rest of the period, the UK continued to play a preeminent role with increasing Australian imports and local manufacture. Examination of archival and published information on techniques used for the sub-floor, floor, wall (construction and structure), fenestration, roof and thermal insulation provide an overview of country of orign, decade of arrival, spread of use and, if relevant, reasons for failure. Forty materials (including earth and brick, stone, cement and concrete, timber and ferrous metals) and twenty-four technologies are documented. Revised dates of first NZ use are provided for eight of these e.g. the shift from balloon to platform framing occurred in the early 1880s rather than 1890s. Three case studies examine different aspects of the techniques (nails 1860 to 1965, hollow concrete blocks 1904 to 1910 and camerated concrete 1908 to 1920). The research shows that timber was the predominant structural (framing) material from 1792 to 1982. From the 1930s there was a shift away from timber construction (external appearance) to a wider range of products, including brick, board (asbestos- and more recently fibre-cement) and concrete. A new chronological classification of house development is proposed. These techniques travelled in a variety of ways and at speeds which indicate over this time New Zealand was technologically well connected and supported an innovative construction sector. The techniques covered are: Boards: asbestos, and cellulose fibre-cement, particle, plywood, pumice, softboard, and hardboard; Bricks: double and veneer; Building paper; Cement and lime: local and imported; Concrete: hollow block, monolithic, reinforced, Camerated, Oratonu and Pearse patents; Fired earth: bricks and terracotta roof tiles; Floors: concrete slab, suspended, and terrazzo; Framing: balloon, braced, light steel, and platform; Insulation: cork, fibreglass, macerated paper, perlite, pumice, foil, and mineral wool; Iron and Steel: cast and wrought iron, steel; Linings: fibrous plaster, plasterboard and wet; metal tile, shingles and slates; Nails: cut, hand-made, wire and plates; Piles: concrete, native timber and stone; Roof: strutted and truss rafter; Roofing: aluminium, corrugated iron, ; Sub-floor: vapour barrier, walls and ventilation; Timber: air and kiln drying, glulam, native, pit-saw and preservative treatments; Wall constructions: earth, log, slab, solid timber, raupo and stone; Weatherboards; and Windows: glass, aluminium, steel and timber frames.</p>

Fibre-Cement Panel Ventilated Façade Smart Control System

This paper outlines a design for a fibre-cement panel ventilated façade smart control system based on the acoustic emission method. The paper also provides methodology and test results, as well as statistical analysis of the three-point bending results with AE signal acquisition as a basis for the development of the system in question. The test items were samples cut from a full-size fibre-cement panel for interior and exterior use, according to the standard guidelines. The recorded acoustic emission signals were classified statistically into four classes, which were assigned to the processes occurring in the material structure as a result of the applied load. The system development was based on the differences between the characteristics of the individual signal classes and their number for each test case, as well as on the different distribution of successive classes over time. Given the results of the tests and the resulting conclusions indicating the applicability of the acoustic emission method (based on signal classification using the k-means algorithm for the assessment of variations in the mechanical parameters of cement-fibre composites), a methodology for such assessment was therefore developed. The approach proposed is a reasonable method for assessing the variation in mechanical parameters of fibre-cement panels on the basis of the parameters determined by the non-destructive method indicated.