Cohesive character in Alfisols, Ultisol and Oxisols in Northeast of Brazil: Relationship of tensile strength with silicon, aluminum and iron from poorly crystalline compounds

2021 ◽  
Vol 24 ◽  
pp. e00361
Author(s):  
Jaedson Cláudio Anunciato Mota ◽  
Cillas Pollicarto da Silva ◽  
Brivaldo Gomes de Almeida ◽  
Ricardo Espíndola Romero ◽  
Thiago Leite de Alencar ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Relationship Of

Field observations on the load–strain–time behaviour of geogrid reinforcement

1994 ◽  
Vol 31 (4) ◽  
pp. 564-569 ◽  
Author(s):  
R.J. Fannin
Keyword(s):  
Tensile Strength ◽  
Field Data ◽  
Constant Load ◽  
Reinforced Soil ◽  
Mean Annual Temperature ◽  
Creep Tests ◽  
Geogrid Reinforcement ◽  
Rapid Loading ◽  
Strip Test ◽  
Relationship Of

Field data are reported that describe the load–strain–time relationship of geogrid reinforcement in a reinforced soil structure. The data are for a period exceeding 5 years and reveal a continued strain in the reinforcement, which occurs at nearly constant load. The response to loading is attributed to creep of the polymeric material. A comparison of the field data with laboratory isochronous load–strain curves, from rapid loading creep tests performed at a temperature similar to the mean annual temperature in the backfill soil, shows the curves describe very well the magnitude of creep strains observed in the field. Implications of the load–strain–time performance data are assessed with reference to the use in design of a tensile strength established from the rapid-loading creep test and wide-width strip test. The need to clarify, in design of polymeric reinforced soil structures, between a safe and allowable tensile strength is emphasized. Key words : reinforced soil, geogrid, creep, tensile strength, strain.

Is cotton-strip tensile strength a surrogate for microbial activity in groundwater?

2010 ◽  
Vol 61 (3) ◽  
pp. 351 ◽  
Author(s):  
M. J. Lategan ◽  
K. Korbel ◽  
G. C. Hose
Keyword(s):  
Tensile Strength ◽  
Microbial Activity ◽  
Strength Loss ◽  
Cellulolytic Activity ◽  
Community Interactions ◽  
The Media ◽  
Microbial Groups ◽  
Relationship Of ◽  
The Relationship ◽  
Cotton Strip

The cotton strip assay uses the loss of tensile strength of cotton strips as a measure of microbial cellulolytic activity. Its suitability for measuring general microbial activity in groundwater was tested by examining the relationship of tensile strength, abundance of cellulolytic organisms and general microbial activity on cotton strips deployed in bores. The hypothesis was that the strength of cotton strips would decline with increasing abundance and activity of cellulolytic organisms, and as cellulolysis makes resources available to other microbial groups, cotton strength loss should also be related to increased overall microbial activity. The correlation between the abundance of cellulolytic organisms and cotton strength was not significant. Two main factors influenced this relationship: (i) effectiveness of the media in detecting cellulolytic moulds and (ii) inter-community interactions. After accounting for the presence of moulds through partial correlation, the relationship between tensile strength and abundance of cellulolytic organisms was stronger and significant. Both cotton strength and abundance of cellulolytic organisms correlated significantly with general microbial activity. These results support the use of the cotton strip assay, and cotton tensile strength as a surrogate for microbial activity in groundwater.

Study on the Relationship between Soil-Cement Parameters and Unconfined Compressive Strength

2011 ◽  
Vol 255-260 ◽  
pp. 4012-4016
Author(s):  
Jun Qing Ma ◽  
You Xi Wang
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Shear Strength ◽  
Unconfined Compressive Strength ◽  
Deformation Modulus ◽  
Soil Cement ◽  
Strength And Deformation ◽  
Cement Soil ◽  
Relationship Of ◽  
The Relationship

This paper studies relationship between soil-cement parameters and unconfined compressive strength. The research in tensile strength and deformation modulus of soil-cement is an important basis for soil-cement failure mechanism and intensity theory. They also impact cracks, deformation and durability of cement-soil structure. Shear strength and deformation of soil-cement is important to the destruction analysis and finite element calculations. Therefore it needs to study on tensile strength, shear strength and deformation modulus of soil-cement. Based on previous experiments, the relationship of tensile strength, shear strength, deformation modulus and unconfined compressive strength of soil-cement are quantitatively studied.

Fracture Behavior of Organic Silicon Rubber at Different Extension Rate

2011 ◽  
Vol 687 ◽  
pp. 571-575
Author(s):  
Xiao Liu ◽  
Wei Fang Zhang ◽  
Sheng Wang Liu ◽  
Wei Guo Hou ◽  
Mei Li Ding
Keyword(s):  
Tensile Strength ◽  
Fracture Behavior ◽  
Tensile Fracture ◽  
Extension Rate ◽  
Silicon Rubber ◽  
Organic Silicon ◽  
Flat Region ◽  
Secondary Cracks ◽  
Rough Region ◽  
Relationship Of

Fracture behavior of organic silicon rubber at the extension rate of 100, 300, 500 and 700 mm/min at room temperature was studied in this paper. The fracture surface morphology was observed by scanning electron microscopy (SEM). Effects of different extension rate on the tensile strength tensile fracture behavior and mechanism were investigated. The results showed that fracture of the organic silicon rubber was composed by flat region and rough region, while the rough region was relatively small. With the increasing extension rate, the area of flat region enlarged while rough region decreased, and the secondary cracks appeared when the extension rate reached critical value. The relationship of the tensile strength and elongation with the extension rate were similar, both of which rised and then droped as the extension rate increased, and further studies were needed for the fracture mechanism.

The Direct Determination of Oxygen in Rubber. The Adaptation of the Ter Meulen Method to Rubber and Its Application to the Study of Aging

1939 ◽  
Vol 12 (2) ◽  
pp. 269-282 ◽  
Author(s):  
H. I. Cramer ◽  
I. J. Sjothun ◽  
L. E. Oneacre
Keyword(s):  
Tensile Strength ◽  
Physical Properties ◽  
Direct Determination ◽  
Sulfur Poisoning ◽  
Oxidation Products ◽  
Oxygen Bomb ◽  
Vulcanized Rubber ◽  
Relationship Of ◽  
The Relationship

Abstract The ter Meulen method for the direct determination of oxygen has been adapted, with modifications, to the analysis of raw and vulcanized rubbers. Raney nickel has been found to be quite effective as the reducing catalyst and to be satisfactorily resistant to sulfur poisoning. The method has been applied to the study of the aging of vulcanized rubber in the Geer oven and oxygen bomb. From this study the following conclusions may be drawn: (1) The increase in combined oxygen is greater in the oxygen bomb than in the Geer oven. (2) Deterioration of rubber in the oxygen bomb involves oxidation primarily, whereas that occurring in the Geer oven involves not only oxidation but also thermal decomposition followed by volatilization of oxidation products. (3) The effectiveness of an antioxidant in retarding the absorption of oxygen in oxygen-bomb aging agrees well with its ability to maintain the physical properties of the stock in which it is present. (4) The deterioration in physical properties of a rubber stock in the oxygen bomb during the early stages of aging is a linear function of the increase in combined oxygen. For stocks containing antioxidants and diphenylguanidine as the accelerator, an increase in combined oxygen of approximately 1.2% corresponds to a decrease in tensile strength of 50%. (5) The relationship of increase in combined oxygen to decrease in tensile strength seems to be affected not only by antioxidants, but also by accelerators of vulcanization.

A Method to Evaluate the Tensile Strength and Stress-Strain Relationship of Carbon Nanofibers, Carbon Nanotubes, and C-Chains

Small ◽  
2005 ◽  
Vol 1 (6) ◽  
pp. 640-644 ◽  
Author(s):  
Alfredo Márquez-Lucero ◽  
Jorge A. Gomez ◽  
Román Caudillo ◽  
Mario Miki-Yoshida ◽  
Miguel José-Yacaman
Keyword(s):  
Carbon Nanotubes ◽  
Tensile Strength ◽  
Carbon Nanofibers ◽  
Stress Strain ◽  
Strain Relationship ◽  
Relationship Of
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