[en] Hugoniot data were obtained for fluid He in the 100 GPa pressure range by shock compression of samples statically precompressed in diamond-anvil cells. The initial (precompressed) He density (ρ₁) for each experiment was tuned to a value between ρ_0L<ρ₁<3.3ρ_0L, where ρ_0L is the zero-pressure density of the cryogenic liquid (ρ_0L=0.123 g/cm³). The maximum observed shock-compression ratios range from ρ/ρ₁=6 for ρ₁=ρ_0L to ρ/ρ₁=4 for ρ₁≥3ρ_0L (i.e., ρ/ρ_0L≥12). Data show an increase in compressibility at the onset of ionization, similar to theoretical predictions

[en] It is shown that the Prieto-Renero equation of state for shock-compressed solids is also valid, under certain conditions, in the case of fluids. Some experimental evidence is found to be in good agreement with theoretical predictions. The basic assumptions and possible limitations are finally discussed. This equation of state finds application in PNE studies. (author)

[en] The authors consider the effect of compressibility of the liner material on the effectiveness of the theta pinch and liner system. They make numerical calculations for the compression dynamics of the liner, the results of which are represented by approximate expressions

[en] A process for interconnecting a three-dimensional pattern of self-propagating polymer waveguides was used to form micro-truss structures with two new unit cell architectures. The structures were formed using a two-dimensional mask with a hexagonal pattern of apertures. Distinct unit cell architectures were possible by exposing the mask to a different number of incident UV exposure beams, which are used to form the waveguides. One unit cell design featured three intersecting waveguides per node, resulting in a structure with three-fold symmetry. The second unit cell design had six-fold symmetry and was characterized by primary nodes with six intersecting waveguides and secondary nodes with two intersecting waveguides. Compression loading experiments were conducted on micro-truss samples with comparable relative density values (ρ/ρ_s = 6.5%), but different unit cell architectures. The addition of secondary nodes in the structures based on the second design led to an increase in compressive modulus of up to 70% and an average increase in peak strength of 42%. The increase in compressive strength and modulus was attributed to a reduction in the truss-member slenderness ratio achieved through increased waveguide connectivity

[en] Methods based on propagation of stress wave phenomena indicate particularly useful in diagnosis of non-metallic materials. The aim of this research is to demonstrate that ultrasonic measurement can produce satisfactory results in predicting certain mechanical properties of standing Aquilaria malaccensis tree. The mechanical information is very important to diagnose the condition inside the trunk. The experiment has been conducted on agarwood samples using a pulse compression ultrasonic system. The apparatus equipped with exponential horn 54 kHz piezoelectric normal probe. Through transmission method of longitudinal ultrasonic wave has been used throughout this experiment to measure velocity of ultrasonic signal through the sample. The result showed that the ultrasonic technique can be used in diagnosing of wood-based samples. (author)

No abstract available

[en] The authors consider the effect of compressibility of the liner material on the effectiveness of the theta-pinch-and-liner system. They make numerical calculations for the compression dynamics of the liner, the results of which are represented by approximate expressions. (author)

[en] This article outlines the recycled aggregate replacement rate and thick-diameter rate of GFRP tube confined in recycled concrete, which has an important impact on the material's compressive strength. Overall, under the same conditions of using recycled concrete, the bearing capacity of short concrete columns can be improved by using broader GFRP tubes. There is a four-fold increase in the bearing capacity of short concrete columns compared to the short column without the restriction of a GFRP tube. The bearing capacity of a short column crafted by recycled coarse aggregate is much lower (about 30%). than those made by common concrete column Additionally, the bearing capacity of short columns made by recycled fine aggregates is also lower than those made by common concrete (approximately 20%). Finally, we find that there is no significant difference between experimental and theoretical data. (paper)

[en] Laser shock compression experiments on precompressed samples offer the possibility to explore extreme material states unreachable by static or single-shock compression techniques alone. We have found significant increases in static compression pressure in a wide-opening and thin diamond precompression cell. This suggests that the precompression target is adaptable to advanced coupling techniques with laser-driven dynamic compression methods. The novel coupling techniques proposed give the potential to access outstanding material states required in planetary and condensed-matter physics.

[en] This research was studying the mechanical characteristics of fibrous based on hydraulic conductivity/permeability and compressibility tests. The samples for the test were obtained by the block sampling method. The location of sampling was on Banyuasin Regency, South Sumatra. The permeability test using constant head method was used for hydraulic conductivity parameter of peat soil. And consolidation test using Oedometer test was also used to find out compressibility characteristics of peat soil. The hydraulic conductivity test results are horizontal hydraulic conductivity (k_h)=6,13x10-4 cm/s and vertical hydraulic conductivity (k_v) = 3.76.10-4 cm/s. The ratio of k_h/k_v (20°C) about 2.04. The coefficient of kh is greater than kv, this is due to the effect of fiber arrangement such as the roots of peat soil. Beside of that, the consolidated test results based on compression index parameters (c_c) are 1,428 and 1,215. The consolidation coefficient parameters (cv, m²/year) were 13,671 (50 kPa), 11,511 (100 kPa), 8,268 (200 kPa), and 3,312 (400 kPa) from the Banyu Urip Dusun III sample. The results of parameter c_v can be affected by applied the pressure where the greater the pressure the smaller the value of c_v. (paper)