There is a need for landfill cap cover to suppress water infiltration to waste while simultaneously promoting rapid gas permeation. We have developed geocomposites (GCs), comprising a micro-porous sheet which is waterproof but have gas permeability, coated with nonwovens to protect it, and investigated the characteristics of GCs as a landfill cap cover. In this study, the protective characteristics of nonwovens in GCs were evaluated by examining the resistance to water penetration (RTWP) of GCs and porous sheet after puncture deformations. Puncture tests on GCs and their constituents were also carried out when they were laid out and fixed on compacted soil. Results showed that the RTWPs of GCs remained unchanged even when displacement due to puncture deformation reached approximately 60-70% of that at the maximum puncture load. In addition, GCs exhibited a higher allowable puncture load and higher allowable displacement in puncture deformations than porous sheet when laid out on highly compacted soil. It was suggested that GC would remain waterproof even if gravel having a maximum grain size of 40 mm deformed GC on compacted soil and became half-buried it.

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A human body model for clothing simulation should reflect inner mechanical characteristics, because shape of clothing is defined by mechanical interactions between clothing and human body. A technique that estimates unknown inner structure of human body is proposed, as it is not easy to measure inner structure of each person. Isomorphic mesh that we proposed was utilized to have one-to-one correspondence between points on different human body surfaces. Mesh structure of isomorphic mesh is identical for any human body surface, and any point on a human body surface can be corresponded to a point on another human body surface. Unknown inner structure of a human body was estimated by deforming mass-spring model of human body according to correspondence of surface shapes. From the results, possibility of the estimation was suggested. Improvement of accuracy of the estimation is expected by setting of proper parameters of the mass-spring model with results of measurement of inner structures of human bodies.

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The effect of relative humidity (RH) on feather-powder-coated polyethylene terephthalate (PET) films was evaluated with respect to surface friction, surface roughness and compression properties. Three different feather powder contents in polyurethane printing layers were coated on PET films using a gravure printing method. The friction coefficient of the feather powder coated films was lower than the reference films. Both the friction coefficient and compression deformation increased slowly at low RH and then rose sharply above 80% RH. Therefore, to minimize the degradation of feather powder coatings and increase the friction coefficient at high RH, a feather powder content of more than 20 wt% and 24 μm print thickness are required for moisture sensitive materials. The nature of friction in feather powder coated films involves adhesion at the point of contact with the film in accordance with compression deformation of the feather powders.

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Excavated organic materials such as textile fabrics are usually heavily degraded and hence their scientific identification is rather difficult. The authors are continuing the analysis of degraded natural textile fibers using FT-IR microscopy to clarify their general characteristics at molecular level. In this report, the infrared spectra of silk fibers found at the Fujinoki tumulus were analyzed in detail. The most remarkable change of spectral patterns in degraded silk fibers compared with those of modern silk fibers was the broad superposed appearance of amide I and II absorption peaks. As a result of the investigation of the secondary structure of fibroin molecules, the main reason for the spectral deformation was found to be the increase in crystallinity associated with degradations.
In this research, the FT-IR microscope at JASRI was used. It requires only very minute samples due to the bright IR light source using synchrotron radiation. This makes it convenient for the study of cultural properties.
The identification of silk fibers in degraded state undoubtedly contributes to the understanding of historical features of the remains at a particular tumulus.

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