Influence of Structural Parameters of Nonwoven Geotextiles on Separation and Filtration in Road Construction

2020 ◽  
Vol 20 (4) ◽  
pp. 449-460
Author(s):  
Špela Bezgovšek ◽  
Dunja Šajn Gorjanc ◽  
Boštjan Pulko ◽  
Stanislav Lenart

AbstractNonwoven geotextiles are often used in road construction as a separation layer. They consist of the web of fibers with different orientations. The orientation of fibers has an important influence on physical and mechanical properties of nonwoven geotextiles. The production of nonwoven geotextiles is cheaper in comparison to woven or knitted fabrics which can also be used as separation geotextiles. The purpose of this research was to study the influence of structural properties of nonwoven geotextiles, namely the diameter of fibers and mass and thickness of nonwoven geotextiles, on their mechanical and hydraulic properties. Six types of nonwoven geotextiles were used in the research. They were produced by the drylaid process (carded) using mechanical bonding technique and also with the combination of mechanical and thermal bonding technique. The research confirmed that the bonding technique and structural properties significantly influence the separation and filtration properties of nonwoven geotextiles, such as opening size and water permeability. It was also found that there are no significant differences in mechanical properties, such as viscoelastic properties and compression creep, between the samples in the dry and wet conditions.

2013 ◽  
Vol 740 ◽  
pp. 759-762
Author(s):  
Hao Zeng Bao

In many areas, there are still a development road construction materials, traditionally, often use reinforced concrete, asphalt and other adhesive method to strengthen the low strength of rock and soil anti-freeze expansion coefficient; And now all countries in the world are studying how to use industrial production waste development of new composite materials. One of the most development potential, the production of industrial waste - slime. This paper USES the Russian kazan national construction university experimental methods, in the experiment to improve frost heaving soil physical and mechanical properties of the method for the synthesis of adhesive, based on the feasibility and applicability, environmental assessment of research and analysis, for the use of adhesive put forward a lot of reference value.


2019 ◽  
Vol 2 (3) ◽  
pp. 317-323
Author(s):  
Mehmet Erdem İnce

The fact that weft knitted fabrics has a stretchable, 3D, porous and interlocking structure makes them unique when manufactured from high performance fibers. Knitted fabrics with different architectures exhibit different properties. Different loop forms like tuck and skip stitches with various loop lengths reveal different physical and mechanical properties. Literature review indicated that wisely arrangement of tuck stitches within the pattern repeat alter the weft-knitted fabric structure from natural and synthetic fibers. Therefore, we studied the effect of number and location of tuck stiches on air permeability of weft-knitted fabrics from glass yarn. Single-bed, flat weft knitting machine was used to knit fabrics with different architectures from three-ply glass yarn. The nominal single-end count of used E-glass yarn was 136 tex. It is anticipated that the number and location of tuck stitches within knit pattern effect physical and air permeability properties of weft-knitted fabrics from glass yarn.


2012 ◽  
Vol 238 ◽  
pp. 466-469
Author(s):  
Hong Zhang ◽  
Dong Liang Xun ◽  
Zhao Yang ◽  
Fu Quan Ji

This paper contrastively analyses the consolidation instances of silt with HEC and HAS soil consolidators, also emphatically discusses the influence regularities of the compressive strength of solidified soil with the following factors: the dose of consolidators and the curing time. Meanwhile, from the point of view of experiment, this paper studies the physical and mechanical properties of solidified soil. Case study shows that HEC and HAS soil consolidators behave as well as cement and lime in road-construction engineering, and even that filling subgrade independently. Also, this paper proposes the appropriate value 6% of HEC and HAS soil consolidators for solidifying silt layer, which can be used as reference for the similar geological conditions.


2021 ◽  
Vol 295 (2) ◽  
pp. 271-274
Author(s):  
V. SHCHERBAN ◽  
◽  
A. PETKO ◽  
O. KOLISKO ◽  
Y. SHCHERBAN ◽  
...  

Improving the process of knitting fabrics from Kevlar complex threads on flat knitting machines is to create the minimum necessary tension in the area of formation of the knitted fabric. To ensure this, it is necessary to determine the change in relative tension in the refueling zones of Kevlar complex threads on flat knitting machines. These zones are formed by arranging the thread guides, tension compensation devices, tension devices and thread break control devices in the working area of the supply system to form a spatial filling line for each specific knitting machine. This complex task for flat knitting machines should be based on the use of specially designed computer programs. Given the specifics of processing Kevlar complex threads on flat knitting machines, when determining the relative tension in each zone, it is necessary to use a recursion algorithm, when the output tension of Kevlar complex threads from the previous zone will be the input for the next zone. When determining the tension of Kevlar complex threads, their interaction with the guides of Kevlar complex threads, tension compensation devices, tension devices and devices for controlling the breakage of Kevlar complex threads, it is necessary to take into account the value of Kevlar complex thread diameter, its physical and mechanical properties, deformation, deformation the coefficient of bending stiffness when determining the actual angle of coverage of the guide surface. Ensuring the minimum necessary tension in the area of formation of the knitted fabric will allow to obtain the parameters of the loop structure of property and tactical equipment of servicemen capable of protecting the human body from fire, cold, cutting, barbed weapons, shock and shotgun impact. Minimizing the tension in each zone of the line of Kevlar complex threads on flat knitting machines will reduce the probability of breakage, which is important for improving knitting processes from the standpoint of improving the productivity of flat knitting machines and product quality. Mathematical support of a computer program requires the development of models of thread guides, tension compensation devices, tension devices and thread break control devices, taking into account the real physical and mechanical properties of Kevlar complex threads and real geometric and structural parameters of structural elements of the feed system.


2021 ◽  
Vol 1039 ◽  
pp. 297-306
Author(s):  
Ahmed S.H. Karim ◽  
Zuheer Naji Majeed ◽  
Salih Y. Darweesh

Powder technology has a great impact on the industry and the need for the labor market since this technology has been used to manufacture copper-based composition models with a fixed rate of 5% of (SiC) with nanostructuring of (0,5,10,15,20) %. Regarding nanoscale zirconia (ZrO2), the mineral and ceramic powders were grinded with a grinding time of two hours for the purpose of homogeneity, then the powders were pressed at a pressure of 5 tons and a time of one minute only. Later, the properties were studied and the prepared samples were sintered at 900 °C for two hours.. The physical properties were represented by density and porosity, mechanical properties by compressive strength (samples failed) and wear and structural properties by SEM and EDS. The results showed that the true density and real porosity decreased with the increase in the size of the support ratios, while we noticed an increase in compressive strength with the increase of the added nanoscale ratios. As for the wear, its value decreased to reach the lowest value after sintering and at the ratio of 15% zirconia. Furthermore. the results of the scanning electron microscope showed that the ratio of 15% zirconia is the best percentage in terms of improving physical and mechanical properties. Keywords: nanozirconia, compressive strength, Thermal sintering, porosity.


2015 ◽  
Vol 10 (2) ◽  
pp. 155892501501000
Author(s):  
R. Varadaraju ◽  
J. Srinivasan

Knitted fabrics are preferred as clothing materials because of of their outstanding comfort quality. 16 plain knitted fabric samples were produced from 4 combed ring spun yarn of linear densities 29.5 Tex, 23.6, Tex 19.7 Tex and 17.4 Tex and 4 different stitch lengths from each yarn linear density were selected for this study. The fabric samples were relaxed and then tested for tensile shear and bending properties using Kawabata tester's. KES- FB1and KES- FB2. The effect of various fabric structural parameters on fabric low stress mechanical properties was studied. The fabric shear rigidity, bending rigidity, shear hysteresis, bending hysteresis, and tensile linearity were positively correlated with the fabric GSM, thickness, and tightness factor and negatively correlated with fabric linear Stitch modulus, areal stitch modulus, volume stitch modulus, and porosity. The fabric tensile elongation was positively correlated with the fabric linear stitch modulus, areal stitch modulus, volume Stitch modulus, and porosity and negatively correlated with the fabric GSM, thickness, and fabric tightness factor. The above properties were higher in course direction than in wale direction. Separate prediction equations were developed for fabric low stress mechanical properties from Tightness factor, Volume Stitch modulus, and Porosity


Author(s):  
V. V. Ilchenko ◽  
V. V. Tymoshevskyi ◽  
R. A. Mishchenko ◽  
D. S. Lyashko ◽  
V. V. Riznyk

The most common ways of milled asphalt re-use, what is formed during road topping repair is considered. The results of experimental studies of preparation technology features and physical and mechanical properties of recycled hot mix asphalt determination based on milled asphalt with plastic fiber addition that obtained from industrial waste is presented. Defined regulations correspondence obtained recycled hot mix asphalt and ways of their use in road construction is determined.


Author(s):  
M. Vysotskaya ◽  
M. Lashin ◽  
A. Kurlykina

The article deals with the problem of using soils represented by sand with a significant content of shell in the construction of embankments of railways and highways. The review of literature sources on this topic did not yield any results, which aroused interest in the possibility of using this soil. Research has been carried out to determine the main physical and mechanical properties of shell sand. Data showing the dynamics of changes in the physical and mechanical properties of the soil during compaction are obtained. The dependence of the reduction of partial residues from 10 to 0.1 sieves is revealed. The maximum increase in the partial remainder occurs on the screen 0,1. Obviously, these changes are the result of grinding the soil under the influence of a large mechanical load and are one of the factors reducing filtration in this soil. It is found that the value of the filtration coefficient at the input control is 2.58 m/day., after compaction of the same soil in the body of the embankment, the filtration coefficient fell to-1.51 m/day. Thus, there is a decrease in the filtration coefficient after compaction of the soil by 41.5% in comparison with the input tests of the soil. The need for further research to find technological solutions for the use of such soil on road construction sites is justified.


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