A Review of the Plastic Limit Test by Means of Rolling Paths

Abstract: In the project report, an attempt is made to design a road, based on the principles of pavement design and cost analysis of y two methods (Group Indexed and CBR Method). On the existing alignment of the road, soil samples are collected for the determination of soil characteristics like consistency limits, sieve analysis, C.B.R. values etc. Based on this the thickness of the pavement (flexible) is designed. The alignment of the road is also designed and fixed by surveying and leveling. The total road length being 497 meters of which, one section is 247m, other is 200m and the third section is 50m. The site selected for this study is of village road near Korba, Korba district of Chhattisgarh, India. Keywords: GI Method, Flexible Pavement, CBR Method, Liquid Limit Test, Plastic Limit, Standard Proctor test, OMS & MDD.

Download Full-text

Experimental study on the basic physical properties of diesel contaminated soil

E3S Web of Conferences ◽

10.1051/e3sconf/202016502008 ◽

2020 ◽

Vol 165 ◽

pp. 02008

Author(s):

Xiaohong He ◽

Fan Liu ◽

Guang Li ◽

Hai Lu

Keyword(s):

Specific Gravity ◽

Physical Properties ◽

Soil Sample ◽

Contaminated Soil ◽

Oil Content ◽

Great Influence ◽

Diesel Oil ◽

Liquid Limit ◽

Plastic Limit ◽

Limit Test

In order to study the change of the properties of petroleum contaminated soil, the samples of diesel contaminated soil with different degrees of pollution were prepared manually, and their basic physical properties were tested through the particle test, specific gravity test and liquid plastic limit test. The results show that the diesel oil has a great influence on the particle size composition of soil, and the diesel oil makes the content of silt decrease, while the clay increase obviously; the specific gravity of soil sample decreases with the increase of oil content, and it is smaller than the proportion of unpolluted soil sample; the influence of diesel oil on the liquid-plastic limit of soil is different, the plastic limit of soil decreases with the increase of oil content, and the liquid limit increases first at a certain oil content, it reaches a peak value and then decreases.

Download Full-text

Review of Recent Developments and Understanding of Atterberg Limits Determinations

Geotechnics ◽

10.3390/geotechnics1010004 ◽

2021 ◽

Vol 1 (1) ◽

pp. 59-75

Author(s):

Brendan C. O’Kelly

Keyword(s):

Water Content ◽

Experimental Testing ◽

Soil Classification ◽

Liquid Limit ◽

Engineering Industry ◽

Plastic Limit ◽

Fine Grained ◽

Limit Test ◽

Fine Grained Soil ◽

Thread Rolling

Among the most commonly specified tests in the geotechnical engineering industry, the liquid limit and plastic limit tests are principally used for (i) deducing useful design parameter values from existing correlations with these consistency limits and (ii) for classifying fine-grained soils, typically employing the Casagrande-style plasticity chart. This updated state-of-the-art review paper gives a comprehensive presentation of salient latest research and understanding of soil consistency limits determinations/measurement, elaborating concisely on the many standardized and proposed experimental testing approaches, their various fundamental aspects and possibly pitfalls, as well as some very recent alternative proposals for consistency limits determinations. Specific attention is given to fall cone testing methods advocated (but totally unsuitable) for plastic limit determination; that is, the water content at the plastic–brittle transition point, as defined using the hand rolling of threads method. A framework (utilizing strength-based fall cone-derived parameters) appropriate for correlating shear strength variation with water content over the conventional plastic range is presented. This paper then describes two new fine-grained soil classification system advancements (charts) that do not rely on the thread-rolling plastic limit test, known to have high operator variability, and concludes by discussing alternative and emerging proposals for consistency limits determinations and fine-grained soil classification.

Download Full-text

Pengaruh Penambahan Abu Kayu Dan Abu Bambu Terhadap Kepadatan Tanah Lempung

Jurnal Manajemen Teknologi & Teknik Sipil ◽

10.30737/jurmateks.v3i2.1077 ◽

2020 ◽

Vol 3 (2) ◽

pp. 191

Author(s):

Vella Maulina Kris Putri ◽

Agata Iwan Candra ◽

Ahmad Ridwan

Keyword(s):

Surface Runoff ◽

Clay Soil ◽

Wood Ash ◽

Road Surface ◽

Plastic Limit ◽

Test Items ◽

Native Soil

The soil has an important role in construction, namely as the loading of soil on clay. It is necessary to improve the nature of the shrinkage. The authors conducted the study to increase the strength of clay by adding wood ashes and bamboo ashes. Wood ash and bamboo ash have pozzolan properties expected to add power to clay when weighted, would drop significantly. Material compares in this study using a mix of wood ash and bamboo ash with a variation of 0%, 4%, 8%, and 12%. Meanwhile, the clay soil is taken directly from the ravaged area, from bulging villages, from the grid district. The results showed that the soil is categorized as montmorillonite soil with properties that can damage light structures and road surface runoff. After adding wood and bamboo ash, it showed optimum results of 12% of the dry fixed test items showing a liquid limit’s value at 41,00%, plastic limit at 28,43%, and the net value of plastic limit at 12,57%. When testing for solidification using native soil at a dry volume of 7,91, gr/cm rainfall can increase by 10,42 gr/cm additives after adding 12% of wood ash and bamboo ash.Tanah memiliki peran penting dalam konstruksi yaitu sebagai pembebanan tanah pada tanah liat. Perlu untuk memperbaiki sifat penyusutan. Penulis melakukan penelitian untuk meningkatkan kekuatan tanah liat dengan cara menambahkan abu kayu dan abu bambu. Abu kayu dan abu bambu memiliki sifat pozzolan yang diharapkan dapat menambah kekuatan pada tanah liat saat tertimbang, akan turun secara signifikan. Perbandingan material dalam penelitian ini menggunakan campuran abu kayu dan abu bambu dengan variasi 0%, 4%, 8%, dan 12%. Sementara itu, tanah lempung diambil langsung dari area yang rusak, dari desa-desa yang menggembung, dari grid distrik. Hasil penelitian menunjukkan bahwa tanah tersebut dikategorikan sebagai tanah montmorillonite dengan sifat yang dapat merusak struktur ringan dan aliran permukaan jalan. Setelah dilakukan penambahan abu kayu dan bambu didapatkan hasil optimum dari 12% benda uji tetap kering yang menunjukkan nilai batas cair 41,00%, batas plastis 28,43%, dan nilai bersih batas plastis 12,57%. Pada pengujian solidifikasi menggunakan tanah asli pada volume kering 7,91 gr / cm curah hujan dapat meningkat sebesar 10,42 gr / cm aditif setelah penambahan 12% abu kayu dan abu bambu.

Download Full-text

Robust Test Method of TSOP PEMs for Space Application

ISTFA 2019: Conference Proceedings from the 45th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2019p0513 ◽

2019 ◽

Author(s):

Yasunobu Iwai ◽

Koichi Shinozaki ◽

Daiki Tanaka

Keyword(s):

Evaluation Method ◽

Low Cost ◽

Reliability Evaluation ◽

Test Method ◽

Thermal Shock Test ◽

Space Application ◽

Space Applications ◽

Limit Test ◽

Long Time ◽

Short Time

Abstract Compared with space parts, consumer parts are highly functional, low cost, compact and lightweight. Therefore, their increased usage in space applications is expected. Prior testing and evaluation on space applicability are necessary because consumer parts do not have quality guarantees for space application [1]. However, in the conventional reliability evaluation method, the test takes a long time, and the problem is that the robustness of the target sample can’t be evaluated in a short time. In this report, we apply to the latest TSOP PEM (Thin Small Outline Package Plastic Encapsulated Microcircuit) an evaluation method that combines preconditioning and HALT (Highly Accelerated Limit Test), which is a test method that causes failures in a short time under very severe environmental conditions. We show that this method can evaluate the robustness of TSOP PEMs including solder connections in a short time. In addition, the validity of this evaluation method for TSOP PEM is shown by comparing with the evaluation results of thermal shock test and life test, which are conventional reliability evaluation methods.

Download Full-text

Safety Evaluation of Eucalyptus globulus Essential Oils through Acute and Sub-acute Toxicity and Skin Irritation in Mice and Rats

Current Chemical Biology ◽

10.2174/2212796814999200818095036 ◽

2020 ◽

Vol 14 (3) ◽

pp. 187-195

Author(s):

Berhan Mengiste ◽

Tizazu Zenebe ◽

Kassahun Dires ◽

Ermias Lulekal ◽

Awol Mekonnen ◽

...

Keyword(s):

Acute Toxicity ◽

Essential Oil ◽

Eucalyptus Globulus ◽

Biochemical Parameters ◽

Skin Irritation ◽

Toxicity Study ◽

Subacute Toxicity ◽

Acute Toxicity Study ◽

Limit Test ◽

Ointment Formulation

Background: The Eucalyptus globulus extractions have been used by the traditional healers to treat diseases in the study area. Our previous study revealed that the essential oil has antimicrobial and antifungal activity. This study determined phytochemical analysis, skin irritation, acute and subacute toxicity of Eucalyptus globulus essential oil in mice and rats. Methods: The phytochemicals were analyzed using GC-MS mass spectrometry. The acute toxicity study was determined at three dose levels of 1500 mg/kg, 1750mg/kg, and 2000 mg/kg. The essential oil limit test at a dose of 1000 mg/kg was administered to mice for 28 consecutive days for sub-acute toxicity study. The mice mortality, behavioral change, injury and other signs of illness were recorded once daily. Biochemical parameters were evaluated. Liver and kidney were analyzed for histopathological analyses. The 5% ointment formulation was applied to the rat skin to determine skin irritation effects. Results: The Eucalyptus globulus essential oil showed no effect on the mice at a dose of 1500mg/kg and below, but caused signs of toxicity and death at a dose of 1750mg/kg and above compared to the controls (p<0.05). The LD50 value was 1650 mg/kg. There was no significant difference (p > 0.05) in the body weights, gross abnormalities of the organs and biochemical parameters compared to the control at 1000 mg/kg subacute toxicity study. No histopathological changes were detected in the organs tested. The 5% ointment formulation did not show any abnormal skin reaction. Discussion: In the present study, the Eucalyptus globulus essential oil was comparable with other studies in terms of both chemical composition and its effects on sub-acute and topical application. Conclusion: This toxicity study demonstrated that Eucalyptus globulus essential oil is nontoxic at a relatively lower concentration.

Download Full-text

Floor Heave Mechanism and Anti-Slide Piles Control Technology in Deep and Large-Span Chamber

Applied Sciences ◽

10.3390/app11104576 ◽

2021 ◽

Vol 11 (10) ◽

pp. 4576

Author(s):

Jian Shi ◽

Desen Kong

Keyword(s):

Model Test ◽

Shear Failure ◽

Deformation Mode ◽

Control Technology ◽

Plastic Limit ◽

Large Span ◽

Similarity Model ◽

Floor Heave ◽

Plastic Limit Analysis ◽

Local Shear

Based on plastic limit analysis, the deformation and fracture mechanism of the floor in the large-span chambers of deep mines are discussed and a similarity model test is carried out to verify the reliability of the theoretical analysis. The results show that the local shear failure first appears below the loading area and develops to the middle part of the test model with the increase in load; when the local shear failure develops to form a continuous sliding surface, continuous plastic flow deformation occurs; the distribution of the plastic zone and the deformation mode obtained from the similarity model test are basically consistent with the Hill-like deformation mode derived from plastic limit analysis. A control technology with anti-slide piles is proposed in order to deal with floor heave in large-span chambers on the basis of previous work. An approach for determining the supporting parameters of anti-slide piles is deduced. To deal with the floor heave in the −1100 level gangue winch room of the Huafeng Coal Mine, a comprehensive reinforcement scheme with anti-slide piles composed of discarded rails and anti-floating anchors is introduced for the floor heave control of the chambers. Site monitoring results show that the scheme not only effectively restrains the development of floor heave, but also ensures the long-term stability of the chamber floor.

Download Full-text

Assessment of acute and sub-chronic neurotoxicity of Morus alba L. fruits in rodents

Future Journal of Pharmaceutical Sciences ◽

10.1186/s43094-020-00110-5 ◽

2020 ◽

Vol 6 (1) ◽

Author(s):

Arpita Paul ◽

Anshul Shakya ◽

Md Kamaruz Zaman

Keyword(s):

Central Nervous System ◽

Morus Alba ◽

Neuroprotective Activity ◽

Repeated Treatment ◽

Fruit Extract ◽

Hot Plate ◽

Organ Weights ◽

Behavioural Responses ◽

Limit Test ◽

The Central Nervous System

Abstract Background Morus alba L. fruits are consumed since long for their nutritional and medicinal values. Although there were studies on the neuroprotective activity of the fruit extract, safety profile of the fruit extract is not yet explored as per the recommended standard guidelines over the central nervous system (CNS). The present work was aimed to assess the neurotoxicity profile of chemically characterized extract of M. alba L. fruits (MA) using validated OECD guidelines, i.e., 425 and 424 in rodents. Results Neurobehavioural parameters were examined for motor, sensory and behavioural responses using actophotometer, hot plate and light and dark box test, respectively as per OECD 424. Interestingly, no sign of mortality and/or adversity on mice treated per-orally with MA (2000 mg/kg) was observed during the limit test as per OECD 425. Further, rats treated with MA (1000, 300 and 100 mg/kg, p.o.) for 28 days, showed insignificant (p < 0.05) changes in body weight, food consumption, neurobehavioural responses, organ weights and biochemical, haematological and histopathological features when compared with vehicle-treated animals. Conclusion The outcome of findings suggests that MA is safe in acute oral as well as sub-chronic (28 days) administration in mice and rats respectively. MA (1000 mg/kg) did not pose any toxic sign and symptoms on neurobehavioural responses in rats even after 28 days repeated treatment in compliance with OECD 424.

Download Full-text