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Sandwich panels with a core of corrugated cardboard The goal of a research project of the Institute for Steel Construction and Materials Mechanics was to determine the utilization of corrugated cardboard as a core material for sandwich panels for roof and wall cladding. In contrast to common core materials, corrugated cardboard is recyclable and consists of renewable raw materials. The bearing behaviour depends mainly on the paper types and on the orientation of the anisotropic material inside the panel. The weakest orientation has similar stiffness and strength as common core materials. However, these can be exceeded many times by other core orientations. Investigations of the most important building physical parameters have shown that the fire behaviour is slightly better than that of most PU‐sandwich panels. The thermal conductivity in the weakest core orientation is comparable to that of mineral wool, the stronger core orientations show higher thermal conductivity. [ABSTRACT FROM AUTHOR]

The hemp plant Cannabis sativa Linn, referring to industrial hemp, is a high-yielding annual industrial crop grown providing fibers from hemp stalk and oil from hemp seeds. Although hemp is a niche crop, hemp production is currently undergoing a renaissance. More than 30 countries grow hemp, with China being the largest hemp producing and exporting country. Europe and Canada are also important actors in the global hemp market. Traditionally, hemp as a fiber plant has been used for the production of apparels, fabrics, papers, cordages and building materials. The hurds, as waste by-product of fiber production, were used for bedding of animals, the seeds for human nutrition, e.g., as flour, and the oil for a wide range of purposes, from cooking to cosmetics. Hemp has also been an important crop throughout human history for medicine. Other more recent applications include materials for insulation and furniture, automotive composites for interior applications and motor vehicle parts, bioplastics, jewelry and fashion sectors, animal feed, animal bedding, and energy and fuel production. Foods containing hemp seed and oil are currently marketed worldwide for both animal and human nutrition. They also find applications in beverages and in neutraceutical products. Hemp oil is also used for cosmetics and personal care items, paints, printing inks, detergents and solvents. It is estimated that the global market for hemp consists of more than 25,000 products. Currently, the construction and insulation sector, paper and textile industries, and food and nutrition domains are the main markets while the cosmetics and automotive sector are growing markets. Innovative applications, e.g., in the medical and therapeutic domains, cosmeceuticals, phytoremediation, acoustic domain, wastewater treatment, biofuels, biopesticides and biotechnology, open new challenges. Hemp is also the object of numerous fundamental studies. This review presents and discusses the traditional and new uses of industrial hemp. [ABSTRACT FROM AUTHOR]

Novel sandwich composites made of syntactic foam core and paper skin were developed as potential building materials. Interface bonding between core and skin was controlled by varying starch content. Two different microsphere size groups were employed for syntactic foam core manufacturing based on the pre-mold processing method. Properties of skin paper with starch adhesive on were found to be affected by drying time of starch adhesive. Mechanical behavior of manufactured sandwich composites in relation with properties of constituent materials was studied. Skin paper contributed to increase up to 40% in estimated flexural strength over syntactic foams, depending on starch content in adhesive between syntactic foam core and paper skin. Small microsphere size group for syntactic foam core was found to be advantageous in strengthening of sandwich composites for a given starch content in adhesive. This finding was in agreement with calculated values of estimated shear stress at interface between skin and core. Failure process of the sandwich composites was discussed in relation with load–deflection curves. Cracking of syntactic foam core was detected to be the first event in sandwich composite failure sequence. Hygroscopic behavior of syntactic foam panels was investigated. Moisture content in the foam was measured to be high for high starch content in the foam panels. No significant moisture effect on flexural strength of syntactic foam panels after being subjected to moisture about 2 months was found for both microsphere size groups. However, substantial decrease (28%) in flexural modulus was found for the foam panels made of large microspheres although not much moisture effect was found on that of small microspheres. [ABSTRACT FROM PUBLISHER]

• Bricks made by bottom ashes, cellulose fibers and clay have been successfully made and tested. • Optimum blends are made of 70% of clay, 25% of bottom ashes and 5% of cellulose fibers. • The so made bricks comply mechanical requirements and are 20% lighter. • Lower thermal conductivity and equal specific heat capacity is achieved. • Toxicity analysis abides by standards in force. The paper and pulp industry (PPI) is permanently searching for new ways of managing its residues due to the increasing pressure of new environmental concerns and policies adopted worldwide. In addition, the manufacturing of construction materials such as fired clay bricks (FCBs) is also facing the transformation of its traditional market, which is asking for new materials with a lower environmental footprint but equal or even better technological properties. In considering the large mass flows related to both the PPI and FCB industries, several researchers have pointed out the feasibility of replacing clay by residues produced by PPI. However, these approaches have always considered the replacement of a single residue rather than the addition of several new ones. Conversely, by using both residues at once, the overall FCB performance is improved and the feasibility of this circular economy approach is eased. For instance, the addition of woody fibres increases thermal resistance but reduces mechanical strength. Conversely, the addition of ashes produced by PPI improved the mechanical strength by reducing the thermal resistance due to the increasing content of fluxing agents which improve the fired clay matrix structure. For this reason, this paper explores the technological properties achieved by replacing clay with both ashes and fibres provided by PPI in an integrated approach. By following industrial procedures, the so made fired clay bricks (with 20% of ash and 5% of fibres) meet the standard and show approx. 20% less thermal conductivity, with the same thermal capacity and a density reduction of more than 15%. [ABSTRACT FROM AUTHOR]

In this paper, a brief review on reversible dielectric nonlinearity (RDN) was presented and the mechanism of tunability for ferroelectric ceramics was discussed in several different scale levels, such as atomic level (intrinsic nonlinearity described by ferroelectric thermodynamic theory), nano-meter scale (polar nano-region response), submicron scale (ferroelectric domain and domain wall motion), micron scale (polycrystalline structure of ceramics and surface layer) and macroscopic scale (field induced phase transition). It suggests that RDN is a multi-scale phenomenon and is temperature and frequency-sensitive. The halving field E0 in Roberts' Equation may be a good attempt for the quantitating of RDN. The stability of RDN in paraelectric phase is also mentioned. [ABSTRACT FROM AUTHOR]

Small-scale model houses were built with different masonry products in order to investigate the environmental performance of sustainable construction materials. Three model houses were designed and developed as per the standards one with recycled paper mill waste (RPMW)-cement bricks, another with fly ash bricks and the third with ferrocement wall panels. In order to assess the indoor temperature for these particular sustainable building materials, the temperature inside the model houses was monitored over the study location for the period of a year. The economic viability for the developed model houses was also analyzed. Wall surface temperature readings on the exposed south facade were used to estimate thermal conduction of the wall assembly. Detailed analysis revealed that the developed RPMW-cement brick model house was more thermally resistant and economical than the fly ash brick and ferrocement wall panel model houses. Energy efficient building minimizes energy consumption through the reduction of indoor temperature, making the RPMW-cement brick model house the best choice for construction. [ABSTRACT FROM AUTHOR]