scholarly journals Recycled Polyester Geosynthetic Influence on Improvement of Road and Railway Subgrade Bearing Capacity— Laboratory Investigations

Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7264
Author(s):  
Konrad Malicki ◽  
Jarosław Górszczyk ◽  
Zuzana Dimitrovová
Keyword(s):  
Bearing Capacity ◽  
High Resistance ◽  
Laboratory Tests ◽  
Civil Engineering ◽  
Compacted Soil ◽  
Laboratory Conditions ◽  
Cbr Test ◽  
Laboratory Investigations ◽  
Recycled Material

After years of using geosynthetics in civil engineering and infrastructure construction, it has recently become necessary to consider the possibility of recycling and reusing these materials. This paper presents the results of laboratory tests of the effect of recycled geogrid on the bearing capacity of soils using a CBR test. A polyester geosynthetic was selected for testing due to its high resistance to biodegradation and wide application. In a series of laboratory tests, two types of road and railway subgrade were used, mixed with geosynthetic cuttings in two different weight concentrations. The aim of the research was to demonstrate whether old demolition geosynthetics could be used to strengthen road and rail subgrade as recycled material. The influence of the geosynthetic cutting shape was also considered. The obtained results confirm the possibility of using recycled geogrid to improve the bearing capacity of the pavement subgrade, at least under these laboratory conditions. In the case of sand, the use of 2.0% additive causes that the poorly compacted soil obtains sufficient bearing capacity for the layer of road improved subgrade. As expected, the level of this improvement depends on the type of soil and the shape of geogrid cuttings.

scholarly journals Breeding of highly productive varieties of winter triticale resistant to pre-harvest germination of grain in the ear

2021 ◽  
Vol 36 ◽  
pp. 01022
Author(s):  
Valentina Rubets ◽  
Irina Voronchikhina ◽  
Vladimir Pylnev ◽  
Viktor Voronchikhin
Keyword(s):  
Central Region ◽  
High Resistance ◽  
Laboratory Tests ◽  
Field Experiments ◽  
Hexaploid Triticale ◽  
Winter Triticale ◽  
Russian State ◽  
Standard Level ◽  
New Varieties ◽  
Variety Testing

Creation of new varieties of winter hexaploid triticale for the central part of Russia is characterized by increased resistance of grain to germination on the root. The phenomenon of germination on the root is one of the limiting traits that limit the spread of triticale culture in areas of excessive moisture, which is the Central Region of the Non-Chernozem zone. The work was carried out at the Russian State Agrarian University – Moscow Agricultural Academy named after K.A. Timiryazev in 2018-2019. Field experiments were conducted in the fields of the Field Experimental and Breeding Stations. Laboratory tests were carried out at the Department of Genetics, Breeding and Seed Production. As a result of a comprehensive assessment of breeding varieties in the preliminary variety testing, the most valuable sample of winter triticale 228h (Castus x Don) was isolated, which formed a yield at the standard level, and during 3 years of study showed relatively high resistance to pre-harvest germination of grain in the ear. This sample is currently being intensively propagated for transfer to the State Variety Testing in 2020.

scholarly journals On Realistically Attacking Tor with Website Fingerprinting

2016 ◽  
Vol 2016 (4) ◽  
pp. 21-36 ◽  
Author(s):  
Tao Wang ◽  
Ian Goldberg
Keyword(s):  
Background Noise ◽  
Laboratory Tests ◽  
Training Data ◽  
Web Traffic ◽  
Training Set ◽  
Data Set ◽  
Laboratory Conditions ◽  
Testing Data ◽  
In The Wild ◽  
New Algorithms

Abstract Website fingerprinting allows a local, passive observer monitoring a web-browsing client’s encrypted channel to determine her web activity. Previous attacks have shown that website fingerprinting could be a threat to anonymity networks such as Tor under laboratory conditions. However, there are significant differences between laboratory conditions and realistic conditions. First, in laboratory tests we collect the training data set together with the testing data set, so the training data set is fresh, but an attacker may not be able to maintain a fresh data set. Second, laboratory packet sequences correspond to a single page each, but for realistic packet sequences the split between pages is not obvious. Third, packet sequences may include background noise from other types of web traffic. These differences adversely affect website fingerprinting under realistic conditions. In this paper, we tackle these three problems to bridge the gap between laboratory and realistic conditions for website fingerprinting. We show that we can maintain a fresh training set with minimal resources. We demonstrate several classification-based techniques that allow us to split full packet sequences effectively into sequences corresponding to a single page each. We describe several new algorithms for tackling background noise. With our techniques, we are able to build the first website fingerprinting system that can operate directly on packet sequences collected in the wild.

Experimental Study on Fire Resistant of Shield Tunnel Segment in Civil Engineering

2012 ◽  
Vol 568 ◽  
pp. 7-12
Author(s):  
Xin Jun Guo ◽  
Zhi Sheng Xu ◽  
Yan Zhang
Keyword(s):  
Experimental Study ◽  
Temperature Distribution ◽  
Bearing Capacity ◽  
Civil Engineering ◽  
Shield Tunnel ◽  
Temperature Position

Fire resistant behavior is one the main properties of shield tunnel segment in civil engineering. The main objective is to study the regularity of temperature distribution and deflection of shield tunnel segment after fire and the residual bearing capacity after cooling in this paper. According to the tests, a temperature-position fitting curve can be obtained, and it can be obtained that the damaged depth of segment is 7.8cm while heating in RABT curve for 125min. It is found that the residual bearing capacity of segment decrease with the increase of the pre-load, which drops rapidly for it is only about 20% compared to the reference one.

Mechanism of Rubber Cracking

1946 ◽  
Vol 19 (2) ◽  
pp. 406-416 ◽  
Author(s):  
E. F. Powell ◽  
V. E. Gough
Keyword(s):  
Laboratory Tests ◽  
Surface Film ◽  
Factors Affecting ◽  
Laboratory Conditions ◽  
Service Conditions ◽  
Exposure Conditions

Abstract Rubber and rubberlike polymers, in common with other materials which deteriorate on exposure to oxidizing or similar agents, eventually crack under normal atmospheric service conditions. The present paper confines itself to the factors affecting the type and appearance of the cracking which eventually occurs when a surface film of a rubber object (particularly when stressed) hardens and deteriorates in strength from any cause whatsoever. The importance of an understanding of the effects of exposure conditions on the character of the cracking produced cannot be too highly emphasized. This is so even if interest is confined solely to simple tests on new protective paints on an acceptance basis rather than research into surface deterioration. It is probable that many protective agencies have been accepted or rejected for extensive production tests because the initial laboratory tests have either not been representative of service or have been inadequate in scope. This still remains a major problem. The theory presented here has gradually taken shape over a period of some ten years and appears to describe adequately the general findings on the whole gamut of cracking, viz., fine check cracking and isolated deep cracks produced under service and laboratory conditions, the latter covering flexing, roof exposure, ozone and similar tests.

Development and laboratory tests of deformation fiber optic sensors for civil engineering applications

1996 ◽  
Author(s):  
Laurent Vulliet ◽  
Nicoletta Casanova ◽  
Daniele Inaudi ◽  
Annette Osa-Wyser ◽  
Samuel Vurpillot
Keyword(s):  
Laboratory Tests ◽  
Fiber Optic ◽  
Civil Engineering ◽  
Fiber Optic Sensors ◽  
Engineering Applications

The Increasing Laws of the Foundation Strength and Civil Engineering

2011 ◽  
Vol 250-253 ◽  
pp. 2662-2666
Author(s):  
Zhi Hai Qin ◽  
Tong Dong Li
Keyword(s):  
Water Stress ◽  
Bearing Capacity ◽  
Pore Water ◽  
Effective Stress ◽  
Civil Engineering ◽  
Building Construction ◽  
Foundation Pit ◽  
Engineering Construction ◽  
Building Load ◽  
Over Time

In the civil engineering construction, with the building load of building construction or adding storeys, foundation pit dewatering, embankment filling , over time, the pore water stress that is borne by pore water in the foundation decreases gradually, the effective stress that is borne by particle increases gradually, the foundation bearing capacity increases gradually, we use different methods to derive the variation law in the theoretical solution, and carry on the comparison, then get the same conclusion. By using theory to solve the frequently encountered problems during civil engineering construction, including the problems of building construction or adding storeys, foundation pit dewatering, embankment filling, it provides theory basis for both economical and safe civil engineering construction .

scholarly journals Assessment of Skid Resistance of Asphalt Mixtures in Laboratory Conditions

2012 ◽  
Vol 58 (4) ◽  
pp. 521-534 ◽  
Author(s):  
W. Gardziejczyk ◽  
M. Wasilewska
Keyword(s):  
Asphalt Concrete ◽  
Laboratory Tests ◽  
Asphalt Mixtures ◽  
Road Surface ◽  
Skid Resistance ◽  
Mastic Asphalt ◽  
Laboratory Conditions ◽  
University Of Technology ◽  
Road Surfaces ◽  
Stone Mastic Asphalt

AbstractThe aggregate applied for the wearing course has a significant influence on skid resistance of road surfaces. However, it is difficult to evaluate the behaviour of road surface in use on the basis of the Polished Stone Value (PSV) determined for the aggregate according to the so called ‘British method’. The British method, which is currently used in many countries, does not allow to determine the influence of neither the grain size of the aggregate nor the type of the wearing course on skid resistance of road surface. The present paper suggests a method for evaluation of the British Pendulum Number (BPN) for road surfaces in laboratory conditions. The authors assumed the BPN for polished slabs, made from asphalt mixtures, as the criterion. The index was measured with the British Pendulum Tester. The simulation of the process was conducted on research stand (called slab polisher) built at Bialystok University of Technology (BUT). The results of laboratory tests indicate that surfaces from asphalt concrete (AC) have slightly higher values of BPN in comparison with the values determined for surfaces made from stone mastic asphalt (SMA).

scholarly journals Pediatric appendicitis score in the diagnosis of childhood appendicitis: a validation study

2017 ◽  
Vol 4 (6) ◽  
pp. 2196 ◽  
Author(s):  
Kambalabettu Zohara Parveen ◽  
K. Shreedhara Avabratha ◽  
Kishan Shetty
Keyword(s):  
Biopsy Specimen ◽  
Laboratory Tests ◽  
Iliac Fossa ◽  
Diagnostic Value ◽  
College Hospital ◽  
Medical College ◽  
Right Iliac Fossa Pain ◽  
Laboratory Investigations ◽  
A Prospective Study ◽  
Appendicitis Score

Background: Pediatric appendicitis score (PAS) is a scoring system which includes symptoms, physical examination and laboratory tests in children suspected to have appendicitis. The objectives of this study were to analyze the diagnostic value of Paediatric Appendicitis Score and to aid early diagnosis of appendicitis.Methods: A prospective study was done in a Medical College hospital, in Mangalore in children aged between 4-16 years, admitted during study period June to December 2016, with right Iliac fossa pain, suspected to have appendicitis. Data from the children including demographic details, clinical features, laboratory investigations and ultrasound done were recorded in proformas after consent from parents. The PAS score was applied to them. If PAS was between 4-6, PAS scoring was repeated after 6 hours. Investigations done were noted. If child was taken up for surgery, histopathology report of the biopsy specimen was collected. The decision to operate or manage conservatively was taken up by the treating pediatric surgeon. PAS score was compared with ultrasound and biopsy report.Results: Sixty children were included in the study. Anorexia, emesis, migration pain, cough tenderness and leukocytosis were the features most consistently seen in appendicitis. Initial PAS were comparable to the repeat scores. Ultrasound showed presence of appendicitis in 88.3% of the children. Ultrasound showed appendicitis in all children with PAS ≥7. Twenty-six children out of 60 underwent surgery. Out of 20 children with PAS ≥7.15 (75%) were taken up for surgery and biopsy showed appendicitis. Biopsy was done in 26 children, of whom 58.1% had PAS ≥ 7. These findings were statistically significant. Conclusions: Paediatric appendicitis score is a valuable tool in diagnosing childhood appendicitis.

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