strength parameter
Recently Published Documents


TOTAL DOCUMENTS

300
(FIVE YEARS 124)

H-INDEX

21
(FIVE YEARS 3)

2022 ◽  
Vol 1049 ◽  
pp. 75-84
Author(s):  
Sergei Kurashkin ◽  
Daria Rogova ◽  
Alexander Lavrishchev ◽  
Vadim Sergeevich Tynchenko ◽  
Alexander Murygin

The article deals with the problem of obtaining the dependence of the product strength parameter on the welding time, welding temperature and pressure during mechanical tests, leak tests. The relevance of this work is due to the complexity of carrying out field experiments to identify dependencies. In particular, the complexity arises from the duration of diffusion welding and the high cost. Application of the method of regression analysis based on a non-compositional plan of the second order for three factors will allow to restore the dependence of the product strength parameter on the time during which welding was carried out, the temperature at which diffusion welding was carried out or could be carried out and on the applied pressure at which mechanical tests were carried out. In the current study, a non-compositional design of the second order for three factors was used - allowing to restore the dependence of the missing values of the strength of the product. The aim of the research is to improve the quality of mathematical modeling. Application of the proposed approach will make it possible to obtain the strength distribution function depending on time, temperature and pressure using the example of a product made of VT14 titanium alloy and 12X18H10T stainless steel. This will make it possible to obtain optimal parameters for the diffusion welding mode and to improve the quality of the resulting products.


Materials ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 255
Author(s):  
Ruihua Hao ◽  
Zizhao Zhang ◽  
Zezhou Guo ◽  
Xuebang Huang ◽  
Qianli Lv ◽  
...  

This research examined the drying–wetting cycles induced changes in undrained triaxial shear strength parameters and microstructural changes of Yili loess. The drying–wetting cycles were selected as 0, 1, 3, 5, 10, 20 and 30. Then, we collected Yili loess samples and performed unconsolidated-undrained (U-U) triaxial shearing tests to ascertain the variation in shear strength parameters with drying–wetting cycles. Additionally, we investigated the microstructural changes of Yili loess samples under drying–wetting cycles simultaneously via nuclear magnetic resonance (NMR) and scanning electron electroscopy (SEM). Finally, we established a grey correlation model between shear strength and microstructural parameters. Under U-U conditions, the prime finding was that the loess’s shear strength parameters changed overall after drying–wetting cycles; in particular, the internal friction angle φ dropped significantly while the cohesion c changed only slightly during cycles. For all the cycles, the first cycle gave the highest change. Soil morphology deterioration was evident at the initial stage of cycles. During the entire drying–wetting cyclic process, pore size distribution showed progressive variance from two-peak to a single-peak pattern, while both porosity and the fractal dimension of pores increased gradually towards stability. Soil particle morphology became slowly simple and reached the equilibrium state after 20 drying–wetting cycles. Under cyclic drying–wetting stress, the shear strength parameter changes were significantly correlated to microstructural modifications. This investigation was related to loess in the westerly region. The findings were expected to provide new insight into establishment of the connection between microstructure and macro stress–strain state of loess. To some extent, it provided a theoretical basis for the prevention and control of loess engineering geological disasters in Yili, Xinjiang and other areas with similar climate and soil types.


2021 ◽  
Vol 23 (12) ◽  
pp. 262-269
Author(s):  
Dr. R L Ramesh ◽  
◽  
Dr. Nagaraja P S ◽  
Raghavendra R ◽  
Gobinath S ◽  
...  

The Concrete is one of the most important products which are efficiently and effectively used in the field of construction. The usage of natural aggregates in the process of production of concrete was high which lead to huge deficiency of availability of the natural aggregates. At the same time production of cements leads to more environmental pollution. Therefore, the production of concrete was altered by vast usage of admixtures and replacements for natural aggregates. In this paper M60 grade concrete is prepared by using GGBS as a partial replacement of cement which is a good strength building mineral admixture, the steel fibers were also introduced in the concrete to improve the strength parameter and for ease of work with concrete and addition of AUROMIX – 400 which is provided by FOSROC chemicals Bengaluru as super plasticizers. The concrete specimens like Cubes and Cylinders were casted and allowed to curing over a nominal curing period of 7, 14 and 28 days to know the basic mechanical properties of the concrete with the above replacements and at the same time RCC beams were also casted and cured, then post tensioned to know the flexural details of this special concrete.


2021 ◽  
Vol 940 (1) ◽  
pp. 012054
Author(s):  
H Pratikno ◽  
H S Titah ◽  
D M Aisyah

Abstract Steel is an alloy of ferrous metal with a maximum carbon content of 2%. This material is widely used for jetty building structures at rivers, estuary, and coastal areas. Corrosion of steel can occur due to several factors, such as the steel material itself and the surrounding environmental factors. One of the corrosion is biocorrosion that occurs due to the presence of biofouling. This study aims to determine the effect of adding extraction of mangrove (Avicennia marina) as an antifouling compound mixed in epoxy paint through adhesion strength parameter. Then the alloy was applied as a coating on the ASTM A36 steel specimen. The variation of coating composition were 100% of epoxy paint, 90%:10% (epoxy paint and extraction of Avicennia marina), 80% : 20% and 70% : 30%. The results showed that the adhesion strength occurred in 100% of epoxy paint (10.15 ± 0.64 Mpa). The adhesion strength was 8.86 ± 0.21 Mpa, 8.50 ± 0.03 Mpa, and 8.19 ± 0.07 Mpa at ratio of composition coating 90%: 10%, 80%: 20%, and 70%: 30%, respectively. In conclusion, the more mangrove extraction was added, the smaller the adhesion strength.


2021 ◽  
Vol 2021 (12) ◽  
Author(s):  
Xing-Xing Dong ◽  
Tai-Fu Feng ◽  
Hai-Bin Zhang ◽  
Shu-Min Zhao ◽  
Jin-Lei Yang

Abstract Based on the gauge symmetry group SU(3)C ⨂ SU(2)L ⨂ U(1)Y ⨂ U(1)B–L, the minimal supersymmetric extension of the SM with local B-L gauge symmetry(B-LSSM) has been introduced. In this model, we study the Higgs masses with the one-loop zero temperature effective potential corrections. Besides, the finite temperature effective potentials connected with two U(1)B-L Higgs singlets are deduced specifically. Then we can obtain the gravitational wave spectrums generated from the strong first-order phase transition. In the B-LSSM, with the fine-tuned parameter regions, we can obtain the strength parameter αθ ~ 0.14 and the ratio of speed to Hubble rate β/Hn ~ 5 at nucleation temperature, and then obtain observable gravitational wave signals. The gravitational wave signals can be as strong as h2ΩGW ~ 10–9, which may be detectable in the future experiments.


2021 ◽  
pp. 91-98
Author(s):  
K. F. Ahmed ◽  
T. Sultana ◽  
M. Z. Abedin ◽  
K. A. Farzana

2021 ◽  
Vol 2040 (1) ◽  
pp. 012024
Author(s):  
Yimam Mohammed Yimer ◽  
A. Paul Makesh ◽  
SalihaShukri Muhammed

Abstract Correlation of soil parameters has undeniable benefit in the determination of engineering properties of soil to solve problems in geotechnical Engineering area. The tests were conducted within geotechnical laboratory. These tested soil parameters, used in the correlation analysis are unconfined compressive strength, bulk unit weight and dry unit weight. The aim of this study is proposing a relationship in between the strength parameter with some of the index properties of soils using statistical regression analysis. The linear regression analyses have been done for prediction of unconfined compressive strength (qu ) from bulk and dry unit weight as model-1 and model-2 respectively. And dry unit weight was predicted from bulk unit weight as model-3. Model-4 represents the multiple linear regression analysis to predict qu . The health of developed models is measured by coefficient of determination (R 2) values. Though, model-1, model-2, model-3 and model-4 have R – squared values of 0.9112, 0.9333, 0.9109 and 0.9452 respectively. Therefore, they are correlated strongly and positively. The prediction of unconfined compressive strength of these soils correlated in linear regression, are fairly determined with Model-2 compared with model-1 and model-4 (MLR).


2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Hassan Alsuhabi ◽  
Mohammad Mehdi Saber ◽  
M. M. Abd El-Raouf

In this paper, uniformly most powerful unbiased test for testing the stress-strength model has been presented for the first time. The end of the paper is recommending a method which is appropriate for no large data where a normal asymptotic distribution is not applicable. The previous methods for inference on stress-strength models use almost all the asymptotic properties of maximum likelihood estimators. The distribution of components is considered exponential and generalized logistic. A corresponding unbiased confidence interval is constructed, too. We compare presented methodology with previous methods and show the method of this paper is logically better than other methods. Interesting result is that our recommended method not only uses from small sample size but also has better result than other ones.


Sign in / Sign up

Export Citation Format

Share Document