The Influence of pH Value and SO42- Concentration on Strength of Cemented Soil

2011 ◽  
Vol 233-235 ◽  
pp. 2006-2010 ◽  
Author(s):  
Xiao Qiang Dong ◽  
Xiao Hong Bai ◽  
Yong Kang Lv ◽  
Peng Ju Han

The pH value and SO42- concentration in corrosive environment may affect mechanical property of cemented soil inturn to cause some serious damage to structure. The results of tests show that the unconfined compression strength is decreasing with the increase of H2SO4 solution concentration, increasing with the increase of pH value. The pH value is increasing and the SO42- concentration is decreasing with the increase of corrosive time. So it is concluded that compressive strength is closely rated with the pH value, SO42- concentration of corrosive environment and corrosive time. Finally a equation is set up based on the relationship of compressive strength and factors affected, which contain the reduced coefficient of compressive strength, pH value, SO42- concentration and corrosive time. The calculated and measured values are close so that the equation could be used in practical design for reference.

2013 ◽  
Vol 664 ◽  
pp. 760-763 ◽  
Author(s):  
Xin Zhang ◽  
Xin Ping Zhang ◽  
Hong Tao Peng ◽  
Qiang Xia ◽  
Jun Wang

TerraZyme as an enzymatic soil stabilizer was used in this research. The stabilized soil was mixed with TerraZyme in proper proportion to determine the relationship of unconfined compression strength and microstructure caused by the introduction of TerraZyme. The experimental results show that the unconfined compressive strength of stabilized soil with TerraZyme added is higher than that without TerraZyme. The micrographs of scanning election microscopy (SEM) indicate that the microstructure of the stabilized soil sample with TerraZyme added is denser than that without TerraZyme. This is because the particles of stabilized soil sample treated with TerraZyme are more coarse and blocky than those untreated with TerraZyme. The stabilized soil is with fewer pores than that without TerraZyme. This kind of compact microstructure should be the basis of higher unconfined compressive strength of stabilized soil with TerraZyme added.


TAPPI Journal ◽  
2009 ◽  
Vol 8 (6) ◽  
pp. 24-28
Author(s):  
CORY JAY WILSON ◽  
BENJAMIN FRANK

TAPPI test T811 is the specified method to ascertain ECT relative to box manufacturer’s certification compliance of corrugated fiberboard under Rule 41/ Alternate Item 222. T811 test sample heights were derived from typical board constructions at the time of the test method’s initial development. New, smaller flute sizes have since been developed, and the use of lighter weight boards has become more common. The T811 test method includes sample specifications for typical A-flute, B-flute, and C-flute singlewall (and doublewall and triplewall) structures, but not for newer thinner E-flute or F-flute structures. This research explores the relationship of ECT sample height to measured compressive load, in an effort to determine valid E-flute and F-flute ECT sample heights for use with the T811 method. Through this process, it identifies challenges present in our use of current ECT test methods as a measure of intrinsic compressive strength for smaller flute structures. The data does not support the use of TAPPI T 811 for ECT measurement for E and F flute structures, and demonstrates inconsistencies with current height specifi-cations for some lightweight B flute.


2015 ◽  
Vol 6 (2) ◽  
Author(s):  
Ginu George ◽  
Binoy Joseph

Employee engagement is becoming an important area of focus by many HR consultancies in the recent years. Organizations having engaged employees tend to out-perform than employees who are not engaged or disengaged, also it will enable them to compete better in their industry resulting in higher performance, lower turnover, more profitability etc., Despite of all this there are still some industries who are ignorant and neglect the importance of having engaged employees. Therefore there is a necessity for more of academic research on employee engagement which helps in creating awareness to these organizations about the prominence of focusing on employee engagement and the findings will also augments the existing literature on employee engagement. The study was conducted on 433 employees working in travel organizations set up in Bangalore with the purpose of determining the relationship psychological climate (antecedent) has on employee engagement and in turn its relationship with organizational citizenship behavior (outcome). The study also determines the mediating relationship of employee engagement between PC and OCB.


2015 ◽  
Vol 19 (06) ◽  
pp. 1540009 ◽  
Author(s):  
SARAH MAHDJOUR

What do growth-oriented business models look like? While several economic theories, such as the theory of the firm, are based on the assumption that firms aim to maximise their profits, past research has shown that growth intention is heterogeneous among firms and that many business owners prefer to keep their firm at a size that they can manage with few resources. This paper explores the relationship of growth intention and business models, based on a sample of 135 German ICT businesses. Following an exploratory approach, Mann–Whitney U tests are applied to analyse how different business model designs correspond with different levels of growth intention. The results indicate that growth intention relates to business owners’ decisions regarding the provision of consulting services, the level of standardisation in offered products and services, the choice of addressed markets, the implementation of competitive strategies based on cost efficiency and of revenue streams based on one-time- and performance-based payments. Furthermore, the results show that growth oriented firms are no more likely than non-growth oriented firms to adapt their business models dynamically to changed internal or external conditions.


2021 ◽  
Vol 213 (10) ◽  
pp. 75-80
Author(s):  
E. Razhina

Abstract. The aim of this work is to investigate the relationship between indicators of cicatricial digestion and linearity of cows. Methods. The research was carried out in the breeding enterprises of the Sverdlovsk region on the livestock of Ural-type cows. Cicatricial fluid was collected with an oropharyngeal rubber probe, and a wooden yaw was also used. Cicatricial content was assessed at the Chelyabinsk Interregional Veterinary Laboratory. The pH value was determined by the electrometric method, VFA – in the Markgam apparatus, ammonia – by the microdiffusion method. Ciliates – in Goryaev’s chamber and under a microscope, bacteria – under a microscope with the addition of sodium chloride solution. Statistical data processing was carried out in the Microsoft Office Excel 2010 program. Results. In terms of the number of ciliates and bacteria in the rumen fluid, the Montwick Chieftain cows, characterized by high productive qualities, had an advantage. In terms of pH and VFA, the Vis Back Ideal line was the best. There were no significant differences between the groups in terms of the amount of ammonia in the rumen. The best animals from the point of view of influence on cicatricial metabolism were the animals of the Vis Back Ideal and Montwick Chieftain lineage. Scientific novelty. Studies have shown that linearity is associated with cicatricial digestion in cows. The relationship of bull lines with indicators of cicatricial metabolism of cows has been determined for the first time. The food in the rumen is digested due to the action of bacteria, ciliates, and fungi. An environment has been created in the rumen for the active development of microflora. Bacteria are able to synthesize amino acids and vitamins. The proventriculus can contain up to 50 species of ciliates.


2014 ◽  
Vol 1015 ◽  
pp. 385-388 ◽  
Author(s):  
Jie Deng

Design a set of practical and effective hydraulic cavitation experiment device, hydraulic cavitation reactor, using porous plate for nitro phenol solution to simulate wastewater, respectively in different cavitation number initial pH value, initial concentration of the waste water, waste water, the cycle time, use different types of porous surface processing and analysis, through the experimental research, it is concluded that these factors and the relationship of nitro phenol degradation rate.


2011 ◽  
Vol 52-54 ◽  
pp. 1846-1854
Author(s):  
Lei Zhu ◽  
Hua Jie Zhang

In order to research the mechanical properties and microstructure change regulation of cement-mixed soil under erosion environment, several experiments are carried out in laboratory. The changes of shear strength of cement-mixed soil are recorded under different erosion environments and in different erosion periods. Their corresponding photomicrographs are also shot to reveal the damage on cement-mixed soil under erosion environment. The results indicate that the shear strength of cement-mixed soil in erosion solutions is worse than the strength by the natural curing in the corresponding period. As erosion time increases the strength of cement-mixed soil dipped in , and solutions keeps on downtrend, whereas the strength of that dipped in unpolluted water and solution presents upward trend. The erosive effects of cement-mixed soil are mainly caused by and , meantime has more prominent erosive effect on cement-mixed soil than . Accompanying with stadium increasing quantitative parameters of microstructures are all varying markedly and have certain regulation which testifies the notable relativity between the shear strength and microstructural parameters. Liner regression methods are set up to indicate the relationship of shear strength indexes and microstructural parameters in the erosion environment.


2011 ◽  
Vol 328-330 ◽  
pp. 1475-1482 ◽  
Author(s):  
M. M. A. Abdullah ◽  
H. Kamarudin ◽  
M. Bnhussain ◽  
I. Khairul Nizar ◽  
A.R. Rafiza ◽  
...  

Geopolymer, produced by the reaction of fly ash with an alkaline activator (mixture of Na2SiO3 and NaOH solutions), is an alternative to the use of ordinary Portland cement (OPC) in the construction industry. However, there are salient parameters that affecting the compressive strength of geopolymer. In this research, the effects of various NaOH molarities, Na2SiO3/NaOH ratios, fly ash/alkaline activator, and curing temperature to the strength of geopolymer paste fly ash were studied. Tests were carried out on 50 x 50 x 50 mm cube geopolymer specimens. Compression tests were conducted on the seventh day of testing for all samples. The test results revealed that a 12 M NaOH solution produced the highest compressive strength for the geopolymer. The combination mass ratios of fly ash/alkaline activator and Na2SiO3/NaOH of 2.0 and 2.5, respectively, produced the highest compressive strength after seven days. Geopolymer samples cured at 60 °C produced compressive strength as high as 70 MPa.


2011 ◽  
Vol 301-303 ◽  
pp. 1139-1144
Author(s):  
Li Ying Jiang ◽  
Li Jie Ren ◽  
Qing Hua Chen ◽  
Guang Zhao Cui

According to the relationship of glucose content in diabetes saliva and blood, the biosensor for detecting saliva glucose was introduced based on electrochemical detecting principle, glucose oxidase was immobilized onto the surface of electrode by glutaraldehyde cross-linking. The measuring system was designed by using potentiostat for amperometric chemical sensors. The characters of the microsystem has been demonstrated with the detection of standard glucose solution concentration of saliva parameter. Compared with the data obtained from the instrument CHI660A, it showed that has a good linear relation in the linear range of 0-2200µmol/L, with the correlation coefficient of 0.9531.


2011 ◽  
Vol 255-260 ◽  
pp. 4012-4016
Author(s):  
Jun Qing Ma ◽  
You Xi Wang

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.


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