Effect of Volcanic Fines and Gradation on the Deformation and Strength Properties of Detrital Marine Sediments in Hawaii

2003 ◽  
Author(s):  
Horst G. Brandes ◽  
Tonya Johnson
Keyword(s):  
Marine Sediments ◽  
Volume Change ◽  
Frictional Resistance ◽  
Strength Properties ◽  
The Other ◽  
Shallow Waters ◽  
Kaneohe Bay ◽  
Frictional Strength ◽  
Calcareous Sands ◽  
Mixed Sediments

The compressibility and triaxial response of mixed sediments, consisting of volcanic and marine calcareous fractions, are investigated for a series of samples taken in the nearshore shallow waters of Kaneohe Bay in Hawaii. The results suggest that the presence of coarse detrital calcareous sands dominates the overall behavior if present in sufficiently large quantities, resulting in low compressibilities similar to that of silica sands and friction angles larger than that for most terrigenous sands at comparable densities. Larger than expected frictional resistance is attributed to the volume change tendencies of the non-uniform grains. On the other hand, when significant fines are present, whether of a volcanic nature or consisting of silty carbonate residue, compressibility tends to increase and frictional strength tends to decrease.

Improved Bond reliability through the use of Auxiliary Wires (Security Bumps and Stand-Off Stitch)

2010 ◽  
Vol 2010 (1) ◽  
pp. 000474-000478 ◽  
Author(s):  
David J Rasmussen ◽  
Rodney Thompson
Keyword(s):  
Circuit Design ◽  
Heat Affected Zone ◽  
High Reliability ◽  
Strength Properties ◽  
The Other ◽  
Wire Loop ◽  
The Wire ◽  
Die Bonding ◽  
Lower Loop ◽  
Major Impediment

Whether the need is due to poorly bondable materials, non-flat bonding surfaces, odd packaging situations, or just the need for high reliability; the integrity of a wire bond interconnect can usually be greatly improved through the proper use of Auxiliary Wires. Auxiliary Wires are defined as Security Wires, Security Bumps, or Stand-Off Stitch (aka Stitch on Bump). The old stand-by Security Wire has been an asset for several decades, however, this is being replaced by Security Bumps which require a smaller second bond termination area. Further, Stand-Off Stitch (SOS) has many more applications and also has many side benefits that could be incorporated into a circuit design for better wire strength properties, fewer interconnects (die to die bonding), and lower loops. Stand-Off Stitch bonding involves the placement of a ball bump at one end of the wire interconnect, then placing a wire with another ball at the other end of the interconnect and stitching off the wire on the previous placed ball bump. This results in a near homogeneous stitch bond interconnect to the bump with an inherent improvement in stitch bond pull strength. Another use for SOS is Reverse Bonding (Stitch bond on bump on die bond pad) often resulting in a lower loop profile than standard forward wire loop and the loop is stronger because the wire hasn't been work annealed above the ball (in the Heat Affected Zone). A major impediment to the implementation of SOS is the retraining of visual inspectors and the approval of quality departments.

Lime chlorosis and other factors affecting the distribution of Eucalyptus on coastal sands in Southern Australia

1967 ◽  
Vol 15 (1) ◽  
pp. 95 ◽  
Author(s):  
RF Parsons ◽  
RL Specht
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
The Other ◽  
Alkaline Soils ◽  
Acidic Soils ◽  
Calcareous Sand ◽  
Factors Affecting ◽  
Physiological Tolerance ◽  
Calcareous Sands ◽  
Beach Sands

In southern Australia, deep calcareous and deep siliceous sands each carry a distinctive assemblage of eucalypts. Three of these species with contrasting edaphic ranges were investigated: Eucalyptus baxteri, which is widespread on acidic soils and is never found on highly alkaline soils like the calcareous sands; E. incrassata, which is widespread on acidic and neutral soils, occurs occasionally on some highly alkaline soils, but is also absent from calcareous beach sands; and E. diversifolia, which is found on both acidic and highly alkaline soils and is widespread on calcareous beach sands. All three species occur on siliceous sands, with E. baxteri in wetter areas than the other two species. Comparative pot experiments in which typical calcareous and siliceous sands were used showed that: (1) E. baxteri is stunted by severe lime chlorosis when grown on calcareous sand, while the other two species are not affected. (2) E. baxteri markedly outyields the other two species on siliceous sands. It is suggested that E. baxteri is absent from calcareous sands because it is physiologically intolerant of highly alkaline soils, and that E. baxteri replaces the other two species on the wetter siliceous sands because its faster growth rate enables it to outcompete them when rainfall is adequate. However, the slower growth rates of E. diversifolia and E. incrassata will be accompanied by slower rates of water use and this may give them an advantage over E. baxteri on drier siliceous sands. The wide edaphic range of E. diversifolia is considered to be the outcome of the wide physiological tolerance of individual plants rather than of intraspecific differentiation.

scholarly journals Electronic Measurement of Changes in the Volume of Pore Water During Testing of Soil Samples

1971 ◽  
Vol 8 (2) ◽  
pp. 341-345 ◽  
Author(s):  
R. J. Mitchell ◽  
K. N. Burn
Keyword(s):  
Pore Water ◽  
Volume Change ◽  
Force Transducer ◽  
Soil Samples ◽  
The Other ◽  
Triaxial Testing ◽  
The Core ◽  
Electronic Measurement ◽  
Electronic Recording ◽  
Visual Reading

Two systems are described for electronic recording of changes in the volume of pore water for triaxial testing of soils: one using a miniature force transducer to measure by direct weighing; the other based upon a float system connected to the core of a differential transformer. Both systems provide measurement of volume change at least as accurately as may be obtained by visual reading of burettes graduated to 0.1 cm3, i.e. to ± 0.05 cm3.

scholarly journals Shear Strength of Compacted Clays as Affected by Mineral Content and Wet-Dry Cycles

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Frederick Nai Charkley ◽  
Kunyong Zhang ◽  
Guoxiong Mei
Keyword(s):  
Shear Strength ◽  
Clay Minerals ◽  
Mineral Content ◽  
Strength Properties ◽  
High Plasticity ◽  
Wetting And Drying ◽  
Frictional Strength ◽  
Precautionary Measures ◽  
Weather Changes ◽  
Clay Slopes

The behaviors of high-plasticity clays depend largely on the clay mineral content. Recently, it has been observed that sudden slope failures of most clay slopes occur in regions pronounced with repeated rainfall and sunny climate. The reason for this is still unclear. Examining the effect of clay minerals and drastic weather changes on shear strength will be useful in predicting the performance of structures built in such soils and to take precautionary measures to improve the properties before failure. Therefore, a series of quick direct shearing tests were conducted on 11 artificial clay mixtures. The cohesion and frictional strength properties were determined and linked to the proportion of clay minerals and the number of wetting and drying cycles. The results show a significant reduction in shear strength after exposure to wetting and drying. Generally, montmorillonite-dominated mixtures were less susceptible to the changes in cohesion strength than kaolin-dominated mixtures, and the reduction in frictional strength was relatively insignificant.

Etude hydrogeologique de quelques plaines de la Turquie

1955 ◽  
Vol S6-V (4-6) ◽  
pp. 337-348
Author(s):  
Hugo G. Fournier
Keyword(s):  
Ground Water ◽  
Marine Sediments ◽  
Alluvial Plain ◽  
Border Region ◽  
The Other ◽  
Anatolian Plateau

Abstract Describes the geology and ground-water possibilities of four alluvial plain areas in Turkey, two of which are located along the Syrian border, the other two on the Anatolian plateau. The plain areas of the Syrian border region are composed of Cretaceous and Tertiary marine sediments capped by Quaternary alluvium and, in places, volcanic flows. Water-bearing sequences of alternating permeable limestones and impermeable marls may be present. The ground-water possibilities of the plateau plains, composed of Tertiary lacustrine and volcanic beds capped by Quaternary alluvium and lava, are less favorable.

scholarly journals The genus Alcyonium (Octocorallia: Alcyonacea: Alcyoniidae) in Chile

Zootaxa ◽  
2007 ◽  
Vol 1607 (1) ◽  
pp. 1-19 ◽  
Author(s):  
L. P. VAN OFWEGEN ◽  
V. HÄUSSERMANN ◽  
G. FÖRSTERRA
Keyword(s):  
New Species ◽  
The Other ◽  
Shallow Waters ◽  
Sem Images

Four new species of Alcyonium (Octocorallia: Alcyoniidae) are described from Chile. They occur in the shallow waters of the southern fjord region. One of them is an encrusting species, the other three form digitate colonies. Encrusting forms of A. grandis Casas et al., 1997, and A. haddoni Wright & Studer, 1889 were also found in the fjord region, bringing the number of Alcyonium species recorded for Chile to eight. For all six recently collected species SEM images of sclerites are presented, and a key to the Chilean Alcyonium species is included.

scholarly journals The mechanical viscosity of fluids

1911 ◽  
Vol 85 (579) ◽  
pp. 366-376 ◽  
Keyword(s):  
Cylindrical Surface ◽  
Relative Velocity ◽  
Frictional Resistance ◽  
The Other ◽  
Shearing Stress ◽  
Parallel Channel ◽  
Relative Speed ◽  
Sufficient Time ◽  
Mean Motion ◽  
The Mean

The experiments described in the following paper were undertaken in order to investigate the relation between shearing stress and rate of distortion in fluids which are in eddying or sinuous motion, that is, motion in which the frictional resistance, at the boundaries of the solid over which they move, varies approximately as the square of the relative velocity, as distinguished from that steady or laminar motion in which the frictional resistance is proportional to the first power of the relative speed. This shearing stress has been called by Osborne Reynolds “mechanical viscosity,” i. e ., a “viscosity arising from the molar motion of the fluid and which is not a property of the fluid independent of its motion as is its physical viscosity.” Thus, to quote Reynolds’ statement, in the eddying motion of a fluid in a parallel channel, “although the mean motion at any point taken over a sufficient time is parallel to the axis of the pipe, it is made up of a succession of motions crossing the pipe in different directions.” In this case, the shearing stress at this point on a cylindrical surface coaxial with the pipe “will include the momentum per second parallel to the pipe carried by the cross streams across the surface on which this shearing stress is measured.” On the other hand, “the coefficient of physical viscosity is the coefficient of instantaneous resistance to distortion at a point moving with the fluid.”

A new species of Acrocirrus (Polychaeta: Acrocirridae) from Coconut Island, Oahu, Hawaii

2011 ◽  
Vol 92 (5) ◽  
pp. 1019-1022 ◽  
Author(s):  
Wagner F. Magalhães ◽  
Julie H. Bailey-Brock
Keyword(s):  
New Species ◽  
Unique Feature ◽  
Shallow Waters ◽  
Kaneohe Bay ◽  
A New Species

A new species of Acrocirrus is described from shallow waters of Coconut Island in Kaneohe Bay, Oahu, Hawaii. Acrocirrus bansei sp. nov. is an Acrocirrus whose segment 13 (chaetiger 11) is modified and equipped with a heavy neuropodial acicular hook. This new species is most similar to A. frontifilis based on the presence of notopodial cirri, which have been, up to now, a unique feature of A. frontifilis. The species differ most notably by the absence of the notopodial cirri on the posterior chaetigers. A key to all recognized species of Acrocirrus is presented.

Fragmentation and genotypic diversity of the scleractinian coral Montipora capitata in Kaneohe Bay, Hawaii

2008 ◽  
Vol 89 (1) ◽  
pp. 101-107 ◽  
Author(s):  
A. Nishikawa ◽  
R.A. Kinzie ◽  
K. Sakai
Keyword(s):  
Scleractinian Coral ◽  
Genotypic Diversity ◽  
The Other ◽  
Allozyme Electrophoresis ◽  
Clonal Structure ◽  
Montipora Capitata ◽  
Kaneohe Bay ◽  
Field Investigations ◽  
Sheltered Habitat ◽  
Reef Edge

The fragmentation and genotypic diversity of Montipora capitata was determined in Kaneohe Bay, Hawaii, using field investigations and allozyme electrophoresis. Two stations were established in the Bay, one in the centre (exposed reef edge, EXPO) and the other at the south end (sheltered lagoonal reef, SHEL). Although the number and mean per cent cover of attached colonies did not differ significantly between the two habitats, number and cover of unattached colonies (fragments) were significantly higher at the sheltered habitat. Thirty-seven genotypes were detected in 176 samples using two or three enzyme loci. Although mean genet number did not differ significantly between the two habitats (mean±SE, 8.2±1.2 and 12.2±1.7 in exposed and sheltered reefs, respectively), lower genetic diversity was detected at SHEL (mean NG:N±SE, 0.75±0.08 and 0.50±0.06 for EXPO and SHEL, respectively). There was no evidence of strong clonal structure, i.e. many colonies, but few genets. Sexually produced new genets may account for the high genotypic diversity in M. capitata at these two habitats.

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