236 research outputs found
Γtude de l'adsorption de l'atrazine sur le charbon actif en poudre en prΓ©sence de tensioactifs
Les tensioactifs, adjuvants participant à la formulation des pesticides peuvent se trouver en compétition avec ces derniers lors de l'adsorption sur charbon actif en poudre (CAP) utilisé au cours du traitement de potabilisation des eaux. L'adsorption de l'atrazine, qui reste l'un des produits phytosanitaires le plus souvent détecté dans les eaux de surface malgré les réglementations sur son utilisation, a été étudiée en présence de trois tensioactifs afin de déterminer l'influence de ces derniers; il a été choisi un tensioactif anionique (DSS), cationique (BHTA), et un non ionique (DE6). Les résultats ont montré que quelle que soit la nature du tensioactif, celui-ci diminue toujours l'adsorption de l'atrazine pour des pH variant de 3,5 à 10 ce qui a pour conséquence une diminution à la fois de la constante de vitesse (Adams et Bohart) et de la capacité d'adsorption (Langmuir). L'étude de l'influence de l'ordre d'introduction des différents éléments participant à l'adsorption (CAP, atrazine, tensioactif) a montré que la fixation préalable de DSS anionique, favorisée en milieu acide, inhibe davantage l'élimination de l'atrazine. L'application des modèles d'adsorption compétitive et non compétitive de Langmuir n'a pas permis de définir avec certitude la nature des interactions entre l'herbicide et les différents tensioactifs.Atrazine, in spite of the restrictions concerning its use, remains one of the most prevalent pesticides in natural surface waters. If a sudden pollution incident occurs, powdered activated carbon (PAC) is used during the flocculation step of water treatment; under such circumstances, atrazine might be in adsorption competition with surfactants included in commercial formulations. The aim of this study was thus to determine the influence of three surfactants [anionic (sodium dodecylsulphate, SDS), cationic (hexadecyl-trimethylammonium bromide, HTAB) and nonionic (2-dodecyloxy-pentaethanoxy)-ethanol, DE6)] on atrazine adsorption onto PAC. At pH 5.5, adsorption onto PAC of atrazine alone was estimated to be 230 mg. g-¹; it was inhibited whatever the nature of the surfactant (cationic anionic or nonionic: figs. 2, 3 and 4). The adsorption capacities (Langmuir) and the kinetic constants (Adams & Bohart) decreased in the presence of the surfactants (table 4) and this diminution was most important for HTAB (fig. 5), perhaps the consequence of a steric effect.The adsorption onto PAC of the molecular form of atrazine (pK=1.68) was not affected by the pH variations. However, when the pH was increased (3.5 to 10) in the presence of SDS, adsorption onto PAC of the anionic surfactant decreased and atrazine adsorption increased (fig. 9). In contrast, for the same experimental conditions but with the cationic surfactant HTAB, adsorption of the surfactant increased over the pH range 3.5 to 10 and the relative adsorption of atrazine diminished (fig. 9). The nonionic surfactant DE6 had no influence.A study of the introduction order of the different components (atrazine, SDS surfactant and PAC) showed the same final equilibrium distribution of atrazine was obtained (fig. 10), regardless of the order of introduction. A similar result was obtained for the adsorption of SDS (fig. 11).For all these cases, the Langmuir equation yielded the adsorption capacity for atrazine and the equilibrium constant. However, competitive and noncompetitive adsorption models (table 1) were unsuccessful in predicting the nature of the interactions between atrazine and the surfactants (table 5)
Influence du dodΓ©cylsulfate de sodium sur l'adsorption des acides humiques sur charbon actif en poudre
L'objectif de ce travail est d'Γ©tudier l'influence d'un tensioactif anionique, le dodΓ©cylsulfate de sodium (DSS) sur l'adsorption d'acides humiques (AH), sur le charbon actif en poudre (CAP).L'adsorption sur CAP, en fonction du temps, des AH seuls, puis du DSS seul, a Γ©tΓ© effectuΓ©e en rΓ©acteur discontinu, Γ diffΓ©rents pH (7,0 et 10,5). Les mΓͺmes expΓ©riences ont Γ©tΓ© rΓ©alisΓ©es avec le mΓ©lange des deux composΓ©s et l'on a pu constater une inhibition rΓ©ciproque de leur adsorption, moins importante Γ pH basique (10,5).L'influence de l'ordre d'introduction des coadsorbats, sur l'adsorption de chacun d'eux, a permis de montrer que l'inhibition de l'adsorption des AH sur CAP par le DSS est encore plus importante lorsque les AH sont ajoutΓ©s sur une suspension DSS-CAP dΓ©jΓ en Γ©quilibre. Aucune dΓ©sorption du DSS n'a pu Γͺtre mise en Γ©vidence aprΓ¨s 24 heures. Ces rΓ©sultats pourraient permettre de conclure Γ une adsorption « compΓ©titiveΒ Β» des AH et du DSS sur les mΓͺmes sites superficiels du charbon actif.Ce travail permet de prΓ©ciser les phΓ©nomΓ¨nes d'adsorption pouvant intervenir entre divers micropolluants susceptibles de s'adsorber simultanΓ©ment soit sur des sΓ©diments naturels, soit sur charbon actif lors du traitement des eaux naturelles.The removal of humic acids (HA) from natural waters is a very old yet modern problemΒ : humic substances are at the origin of the coloration of water but also, they give off nocive trihalomethanes during chlorination.Humic acids are also known to be a metal micropollutant vector and their behavior is not well defined when there is coadsorption.The purpose of this work was to study the effect of an anionic surfactant, sodium dodecyl sulphate (SDS), on the adsorption on powdered activated carbon (PAC) of humic substances from a commercial source, as a function of the pH (7.0 or 10.5), as well as the effect of the order of introduction of the coadsorbate.Results (fig. 1 to 3 and fig. 6) showed an inhibition of the adsorption for both HA and SDS in the presence of the coadsorbate. The inhibition was more significant for a pH = 7.0.Results of the influence of the order of introduction of the coadsorbate on the adsorption (fig. 4 and 5) showed a more significant inhibition of HA adsorption when HA were introduced into the equilibrium suspension SDS-PAC (the contact lime was 24 hours).Table 1 gives parameter values of the Langmuir equation for the adsorption on PAC of HA atone or with SDS.All these results suggest that a competition on the same sites occurs during the adsorption on PAC of HA and SDS
A MEMS-based solid propellant microthruster array for space and military applications
Since combustion is an easy way to achieve large quantities of energy from a small volume, we developed a MEMS based solid propellant microthruster array for small spacecraft and micro-air-vehicle applications. A thruster is composed of a fuel chamber layer, a top-side igniter with a micromachined nozzle in the same silicon layer. Layers are assembled by adhesive bonding to give final MEMS array. The thrust force is generated by the combustion of propellant stored in a few millimeter cube chamber. The micro-igniter is a polysilicon resistor deposited on a low stress SiO2/SiNx thin membrane to ensure a good heat transfer to the propellant and thus a low electric power consumption. A large range of thrust force is obtained simply by varying chamber and nozzle geometry parameters in one step of Deep Reactive Ion Etching (DRIE). Experimental tests of ignition and combustion employing home made (DB+x% BP) propellant composed of a Double-Base and Black-Powder. A temperature of 250 therefore degrees C, enough to propellant initiation, is reached for 40 mW of electric power. A combustion rate of about 3.4 mm/s is measured for DB+20% BP propellant and thrust ranges between 0.1 and 3,5 mN are obtained for BP ratio between 10% and 30% using a microthruster of 100 mu m of throat wide
Pelatihan Pemanfaatan Gulma Eceng Gondok sebagai Pupuk Alternatif
Eceng Gondok sebagai masalah bagi jaringan drainase, di Kota Makassar, juga dirasakan oleh berbagai negara di dunia. Di Amerika tanaman eceng gondok dengan nama latin Eichornia crassipes, sejak 1960 oleh pemerintah telah berdiri Water Hyacinth Society yang merupakan asosiasi para ilmuwan, praktisi dan pengusaha untuk mengontrol atau menanggulangi masalah penyebaran eceng gondok. Asosiasi ini kemudian berganti nama menjadi Aquatic Plant management Society (APMS) yang meliputi pengkajian aspek-aspek biologis, ekologis dan pengontrolan pertumbuhan tumbuh-tumbuhan air pada umumnya dan tidak hanya terbatas pada eceng godok. Penelitian mengenai aspek-aspek ekologi eceng gondok di Indonesia sampai saat ini masih belum banyak dilakukan orang, padahal sebagai tanaman yang mengepung di permukaan air ini, memiliki nilai penting yang tinggi, terutama untuk pipik alternatif. Penyebarannya yang cukup luas, penyesuaiannya yang baik terhadap lingkungan, gangguan dan kerugian yang sangat berarti yang dapat ditimbulkannya, cara pengendaliannya yang sulit dan cara pemanfaatannya yang belum diketahui dengan baik sebenarnya merupakan alasan-alasan yang menarik untuk memanfaatkan tanaman ini secara menyeluruh. Salah satunya dengan melatih masyarakat, menjadikannya sebagai pupuk alternatif
Evaluasi Kesesuaian Lahan Pertanaman Karet di Afdeling III PTPN VII (Persero) Unit USAha Kedaton
Karet adalah salah satu komoditas perkebunan unggulan Provinsi Lampung yang tersebar hampir diseluruh Kabupten di Provinsi Lampung. Tahun 2010 pertanaman karet di Provinsi Lampung seluas 119.83 ha dengan total produksi 72.240 ton. Untuk mencapai produksi yang maksimal, maka suatu jenis tanaman harus ditanam pada tempat yang sesuai dengan persyaratan tumbuhnya. Dengan evaluasi kesesuaian lahan dapat diketahui kesesuaian suatu wilayah untuk tanaman karet serta kelayakan secara ekonomi. Penelitian dilakukan dengan pendekatan penilaian kesesuaian lahan kualitatif berdasarkan kriteria Djaenuddin dkk 2000 dan evaluasi kuantitatif adalah analisis finansial dengan menghitung NPV, Net B/C, IRR, dan BEP. Penelitian dilakukan pada lahan pertanaman karet di Field 2005 E PTPN VII (Persero) Unit Usaha Kedaton Way Galih Lampung Selatan pada bulan Agustus 2012. Penelitian dilaksanakan dengan metode survey dengan pendekatan evaluasi lahan secara paralel. Hasil penelitian menunjukkan bahwa lahan pertanaman karet di Field 2005 E PTPN VII Unit Usaha Kedaton Way Galih berdasarkan potensi fisik lingkungan termasuk ke dalam kelas kesesuaian lahan cukup sesuai dengan faktor pembatas ketersediaan air dan retensi hara (S2wanr) dan secara finansial layak untuk dilanjutkan dengan nilai NPV = Rp 132.281.885 ha-1, Net B/C = 2,3, IRR = 24,30% thn-1 , dan BEP = 14 tahun 7 bulan 12 hari
Quantum Coherence Oscillations in Antiferromagnetic Chains
Macroscopic quantum coherence oscillations in mesoscopic antiferromagnets may
appear when the anisotropy potential creates a barrier between the
antiferromagnetic states with opposite orientations of the Neel vector. This
phenomenon is studied for the physical situation of the nuclear spin system of
eight Xe atoms arranged on a magnetic surface along a chain. The oscillation
period is calculated as a function of the chain constant. The environmental
decoherence effects at finite temperature are accounted assuming a dipole
coupling between the spin chain and the fluctuating magnetic field of the
surface. The numerical calculations indicate that the oscillations are damped
by a rate , where is the number of spins and is
the relaxation time of a single spin.Comment: 10 pages, Latex, two postscript figures; submitted to Phys. Rev.
Experimental analysis of behavior and damage of sandwich composite materials in three-point bending. Part 1. Static tests and stiffness degradation at failure studies
The analysis of stiffness and the identification
of rupture mechanisms during and after static
tests of sandwich panels and their components
have been investigated. The sandwich panels,
having cross-ply laminates skins made of glass
fibre and epoxy resin were manufactured by
vacuum moulding and subjected to three-point
bending tests. Two PVC cores of similar type
but with differing densities were investigated.
The effect of core density and its thickness on
the behavior and the damage was highlighted.
In terms of stiffness and load at failure, the
sandwich structure has better mechanical
characteristics compared to its components.ΠΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΠΎ Π΄ΠΎΡΠ»ΡΠ΄ΠΆΠ΅Π½ΠΎ Π·ΠΌΡΠ½Ρ ΠΆΠΎΡΡΡΠΊΠΎΡΡΡ ΡΠ° ΠΏΡΠΎΠ°Π½Π°Π»ΡΠ·ΠΎΠ²Π°Π½ΠΎ ΠΌΠ΅Ρ
Π°Π½ΡΠ·ΠΌΠΈ
ΡΡΠΉΠ½ΡΠ²Π°Π½Π½Ρ ΠΏΡΠΈ ΡΡΠ°ΡΠΈΡΠ½ΠΈΡ
Π²ΠΈΠΏΡΠΎΠ±ΡΠ²Π°Π½Π½ΡΡ
Π±Π°Π³Π°ΡΠΎΡΠ°ΡΠΎΠ²ΠΈΡ
ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ½ΠΈΡ
ΠΏΠ»Π°ΡΡΠΈΠ½ Ρ ΡΡ
ΠΊΠΎΠΌΠΏΠΎΠ½Π΅Π½ΡΡΠ². ΠΠ°Π³Π°ΡΠΎΡΠ°ΡΠΎΠ²Ρ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ½Ρ ΠΏΠ»Π°ΡΡΠΈΠ½ΠΈ Π· ΠΏΠ΅ΡΠ΅Ρ
ΡΠ΅ΡΠ½ΠΈΠΌΠΈ
ΡΠ°ΡΠ°ΠΌΠΈ Π·Ρ ΡΠΊΠ»ΠΎΠ²ΠΎΠ»ΠΎΠΊΠ½Π° ΡΠ° Π΅ΠΏΠΎΠΊΡΠΈΠ΄Π½ΠΎΡ ΡΠΌΠΎΠ»ΠΈ, ΡΠΎ Π²ΠΈΠ³ΠΎΡΠΎΠ²Π»Π΅Π½Ρ
ΠΌΠ΅ΡΠΎΠ΄ΠΎΠΌ Π²Π°ΠΊΡΡΠΌΠ½ΠΎΡ Π²ΡΠ΄Π»ΠΈΠ²ΠΊΠΈ, ΠΏΡΠ΄Π΄Π°Π²Π°Π»ΠΈ Π½Π°Π²Π°Π½ΡΠ°ΠΆΠ΅Π½Π½Ρ ΡΡΠΈΡΠΎΡΠΊΠΎΠ²ΠΈΠΌ Π·Π³ΠΈΠ½ΠΎΠΌ. ΠΠΎΡΠ»ΡΠ΄ΠΆΡΠ²Π°Π»ΠΈ Π΄Π²Π° Π²Π°ΡΡΠ°Π½ΡΠΈ ΠΏΠ»Π°ΡΡΠΈΠ½ Π· ΠΎΠ΄Π½ΠΎΡΠΈΠΏΠ½ΠΈΠΌΠΈ Π½Π°ΠΏΠΎΠ²Π½ΡΠ²Π°ΡΠ°ΠΌΠΈ Π· ΠΏΠΎΠ»Ρ-
Π²ΡΠ½ΡΠ»ΠΎΠΏΠ»Π°ΡΡΠ° ΡΡΠ·Π½ΠΎΡ ΡΡΠ»ΡΠ½ΠΎΡΡΡ. Π ΠΎΠ·Π³Π»ΡΠ½ΡΡΠΎ Π²ΠΏΠ»ΠΈΠ² ΡΡΠ»ΡΠ½ΠΎΡΡΡ Ρ ΡΠΎΠ²ΡΠΈΠ½ΠΈ Π²Π½ΡΡΡΡΡΠ½ΡΠΎΠ³ΠΎ
ΡΠ°ΡΡ Π½Π°ΠΏΠΎΠ²Π½ΡΠ²Π°ΡΠ° Π½Π° ΠΏΠΎΠ²Π΅Π΄ΡΠ½ΠΊΡ ΡΠ° ΠΏΠΎΡΠΊΠΎΠ΄ΠΆΠ΅Π½Π½Ρ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ°. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ,
ΡΠΎ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡ ΡΠ· Π½Π°ΠΏΠΎΠ²Π½ΡΠ²Π°ΡΠ΅ΠΌ Π²Π΅Π»ΠΈΠΊΠΎΡ ΡΡΠ»ΡΠ½ΠΎΡΡΡ ΠΌΠ°Ρ Π±ΡΠ»ΡΡ Π²ΠΈΡΠΎΠΊΡ
Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊΠΈ ΡΡΠ°ΡΠΈΡΠ½ΠΎΡ ΠΌΡΡΠ½ΠΎΡΡΡ Ρ ΡΡΡΠΉΠΊΠΎΡΡΡ ΠΏΠΎΡΡΠ²Π½ΡΠ½ΠΎ Π· ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠΎΠΌ ΡΠ·
Π½Π°ΠΏΠΎΠ²Π½ΡΠ²Π°ΡΠ΅ΠΌ ΠΌΠ΅Π½ΡΠΎΡ ΡΡΠ»ΡΠ½ΠΎΡΡΡ.ΠΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΠΎ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΎ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ ΠΆΠ΅ΡΡΠΊΠΎΡΡΠΈ ΠΈ ΠΏΡΠΎΠ°Π½Π°Π»ΠΈΠ·ΠΈΡΠΎΠ²Π°Π½Ρ ΠΌΠ΅Ρ
Π°Π½ΠΈΠ·ΠΌΡ ΡΠ°Π·ΡΡΡΠ΅Π½ΠΈΡ
ΠΏΡΠΈ ΡΡΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΈΡΠΏΡΡΠ°Π½ΠΈΡΡ
ΠΌΠ½ΠΎΠ³ΠΎΡΠ»ΠΎΠΉΠ½ΡΡ
ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ½ΡΡ
ΠΏΠ»Π°ΡΡΠΈΠ½ ΠΈ ΠΈΡ
ΠΊΠΎΠΌΠΏΠΎΠ½Π΅Π½ΡΠΎΠ².
ΠΠ½ΠΎΠ³ΠΎΡΠ»ΠΎΠΉΠ½ΡΠ΅ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ½ΡΠ΅ ΠΏΠ»Π°ΡΡΠΈΠ½Ρ Ρ ΠΏΠ΅ΡΠ΅ΠΊΡΠ΅ΡΡΠ½ΡΠΌΠΈ ΡΠ»ΠΎΡΠΌΠΈ ΠΈΠ· ΡΡΠ΅ΠΊΠ»ΠΎΠ²ΠΎΠ»ΠΎΠΊΠ½Π° ΠΈ
ΡΠΏΠΎΠΊΡΠΈΠ΄Π½ΠΎΠΉ ΡΠΌΠΎΠ»Ρ, ΠΈΠ·Π³ΠΎΡΠΎΠ²Π»Π΅Π½Π½ΡΠ΅ ΠΌΠ΅ΡΠΎΠ΄ΠΎΠΌ Π²Π°ΠΊΡΡΠΌΠ½ΠΎΠΉ ΠΎΡΠ»ΠΈΠ²ΠΊΠΈ, ΠΏΠΎΠ΄Π²Π΅ΡΠ³Π°Π»ΠΈ Π½Π°Π³ΡΡΠΆΠ΅Π½ΠΈΡ
ΡΡΠ΅Ρ
ΡΠΎΡΠ΅ΡΠ½ΡΠΌ ΠΈΠ·Π³ΠΈΠ±ΠΎΠΌ. ΠΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π»ΠΈ Π΄Π²Π° Π²Π°ΡΠΈΠ°Π½ΡΠ° ΠΏΠ»Π°ΡΡΠΈΠ½ Ρ ΠΎΠ΄Π½ΠΎΡΠΈΠΏΠ½ΡΠΌΠΈ Π½Π°ΠΏΠΎΠ»Π½ΠΈΡΠ΅Π»ΡΠΌΠΈ
ΠΈΠ· ΠΏΠ΅Π½ΠΎΠ²ΠΈΠ½ΠΈΠ»ΠΎΠΏΠ»Π°ΡΡΠ° ΡΠ°Π·Π»ΠΈΡΠ½ΠΎΠΉ ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΠΈ. Π Π°ΡΡΠΌΠΎΡΡΠ΅Π½ΠΎ Π²Π»ΠΈΡΠ½ΠΈΠ΅ ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΠΈ ΠΈ ΡΠΎΠ»ΡΠΈΠ½Ρ
Π²Π½ΡΡΡΠ΅Π½Π½Π΅Π³ΠΎ ΡΠ»ΠΎΡ Π½Π°ΠΏΠΎΠ»Π½ΠΈΡΠ΅Π»Ρ Π½Π° ΠΏΠΎΠ²Π΅Π΄Π΅Π½ΠΈΠ΅ ΠΈ ΠΏΠΎΠ²ΡΠ΅ΠΆΠ΄Π΅Π½ΠΈΠ΅ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ°. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ
ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡ Ρ Π½Π°ΠΏΠΎΠ»Π½ΠΈΡΠ΅Π»Π΅ΠΌ Π±ΠΎΠ»ΡΡΠ΅ΠΉ ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΠΈ ΠΎΠ±Π»Π°Π΄Π°Π΅Ρ Π±ΠΎΠ»Π΅Π΅ Π²ΡΡΠΎΠΊΠΈΠΌΠΈ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊΠ°ΠΌΠΈ
ΡΡΠ°ΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΏΡΠΎΡΠ½ΠΎΡΡΠΈ ΠΈ ΡΡΡΠΎΠΉΡΠΈΠ²ΠΎΡΡΠΈ ΠΏΠΎ ΡΡΠ°Π²Π½Π΅Π½ΠΈΡ Ρ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠΎΠΌ, ΠΈΠΌΠ΅ΡΡΠΈΠΌ Π½Π°ΠΏΠΎΠ»Π½ΠΈΡΠ΅Π»Ρ
ΠΌΠ΅Π½ΡΡΠ΅ΠΉ ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΠΈ
Experimental Analysis of Behavior and Damage of Sandwich Composite Materials in Three-Point Bending. Part 2. Fatigue Test Results and Damage Mechanisms
ΠΡΠΏΠΎΠ»Π½Π΅Π½Ρ ΡΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΡΠ΅ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΡ ΠΆΠ΅ΡΡΠΊΠΎΡΡΠΈ ΠΈ ΠΌΠ΅Ρ
Π°Π½ΠΈΠ·ΠΌΠΎΠ² ΠΏΠΎΠ²ΡΠ΅ΠΆΒΠ΄Π΅Π½ΠΈΡ ΠΏΡΠΈ ΡΡΡΠ°Π»ΠΎΡΡΠ½ΡΡ
ΠΈΡΠΏΡΡΠ°Π½ΠΈΡΡ
ΠΌΠ½ΠΎΠ³ΠΎΡΠ»ΠΎΠΈΜΠ½ΡΡ
ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ½ΠΈΡ
ΠΏΠ»Π°ΡΡΠΈΠ½ Ρ Π½Π°ΠΏΠΎΠ»Π½ΠΈΡΠ΅Π»Π΅ΠΌ ΠΈΠ· ΠΏΠ΅Π½ΠΎΠ²ΠΈΠ½ΠΈΠ»ΠΎΠΏΠ»Π°ΡΡΠ°. ΠΠ½ΠΎΠ³ΠΎΡΠ»ΠΎΠΈΜΠ½ΡΠ΅ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ½ΡΠ΅ ΠΏΠ»Π°ΡΡΠΈΠ½Ρ Ρ ΠΏΠ΅ΡΠ΅ΠΊΡΠ΅ΡΡΠ½ΡΠΌΠΈ ΡΠ»ΠΎΡΠΌΠΈ ΠΈΠ· ΡΡΠ΅ΠΊΠ»ΠΎΒ Π²ΠΎΠ»ΠΎΠΊΠ½Π° ΠΈ ΡΠΏΠΎΠΊΡΠΈΠ΄Π½ΠΎΠΈΜ ΡΠΌΠΎΠ»Ρ, ΠΈΠ·Π³ΠΎΡΠΎΠ²Π»Π΅Π½Π½ΡΠ΅ ΠΌΠ΅ΡΠΎΠ΄ΠΎΠΌ Π²Π°ΠΊΡΡΠΌΠ½ΠΎΠΈΜ ΠΎΡΠ»ΠΈΠ²ΠΊΠΈ, ΠΏΠΎΠ΄Π²Π΅ΡΠ³Π°Π»ΠΈ Π½Π°Π³ΡΡΒΠΆΠ΅Π½ΠΈΡ ΡΡΠ΅Ρ
ΡΠΎΡΠ΅ΡΠ½ΡΠΌ ΠΈΠ·Π³ΠΈΠ±ΠΎΠΌ. ΠΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π»ΠΈ Π΄Π²Π° Π²Π°ΡΠΈΠ°Π½ΡΠ° ΠΏΠ»Π°ΡΡΠΈΠ½ Ρ ΠΎΠ΄Π½ΠΎΡΠΈΠΏΠ½ΡΠΌΠΈ Π½Π°ΠΏΠΎΠ»ΒΠ½ΠΈΡΠ΅Π»ΡΠΌΠΈ ΠΈΠ· ΠΏΠ΅Π½ΠΎΠ²ΠΈΠ½ΠΈΠ»ΠΎΠΏΠ»Π°ΡΡΠ° ΡΠ°Π·Π»ΠΈΡΠ½ΠΎΠΈΜ ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΠΈ. Π Π°ΡΡΠΌΠΎΡΡΠ΅Π½ΠΎ Π²Π»ΠΈΡΠ½ΠΈΠ΅ ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΠΈ ΠΈ ΡΠΎΠ»ΡΠΈΠ½Ρ Π²Π½ΡΡΡΠ΅Π½Π½Π΅Π³ΠΎ ΡΠ»ΠΎΡ Π½Π°ΠΏΠΎΠ»Π½ΠΈΡΠ΅Π»Ρ Π½Π° ΠΏΠΎΠ²Π΅Π΄Π΅Π½ΠΈΠ΅ ΠΈ ΠΏΠΎΠ²ΡΠ΅ΠΆΠ΄Π΅Π½ΠΈΠ΅ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ°. Π‘ ΠΈΡΠΏΠΎΠ»ΡΒΠ·ΠΎΠ²Π°Π½ΠΈΠ΅ΠΌ Π΄Π²ΡΡ
ΡΠ°Π·Π»ΠΈΡΠ½ΡΡ
ΠΌΠΎΠ΄Π΅Π»Π΅ΠΈΜ ΠΈ ΠΊΡΠΈΡΠ΅ΡΠΈΡ ΡΠΈΠΊΠ»ΠΈΡΠ΅ΡΠΊΠΎΠΈΜ Π΄ΠΎΠ»Π³ΠΎΠ²Π΅ΡΠ½ΠΎΡΡΠΈ ΠΏΠΎΡΡΡΠΎΠ΅Π½Ρ ΠΊΡΠΈΠ²ΡΠ΅ ΡΡΡΠ°Π»ΠΎΡΡΠΈ ΠΈ Π²ΡΠΏΠΎΠ»Π½Π΅Π½ ΠΈΡ
ΡΡΠ°Π²Π½ΠΈΡΠ΅Π»ΡΠ½ΡΠΈΜ Π°Π½Π°Π»ΠΈΠ· Ρ ΠΈΠΌΠ΅ΡΡΠΈΠΌΠΈΡΡ Π»ΠΈΡΠ΅ΡΠ°ΡΡΡΠ½ΡΠΌΠΈ Π΄Π°Π½Π½ΡΠΌΠΈ. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡ SD 2 Ρ Π½Π°ΠΏΠΎΠ»Π½ΠΈΡΠ΅Π»Π΅ΠΌ Π±ΠΎΠ»ΡΡΠ΅ΠΈΜ ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΠΈ ΠΎΠ±Π»Π°Π΄Π°Π΅Ρ Π±ΠΎΠ»Π΅Π΅ Π²ΡΡΠΎΠΊΠΈΠΌΠΈ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊΠ°ΠΌΠΈ ΡΡΠ°ΡΠΈΡΠ΅ΡΠΊΠΎΠΈΜ ΠΏΡΠΎΡΠ½ΠΎΡΡΠΈ ΠΈ ΡΡΡΠΎΠΈΜΡΠΈΠ²ΠΎΡΡΠΈ, Π° ΡΠ°ΠΊΠΆΠ΅ ΡΡΡΠ°Π»ΠΎΡΡΠ½ΠΎΠΈΜ ΠΏΡΠΎΡΒΠ½ΠΎΡΡΠΈ ΠΏΠΎ ΡΡΠ°Π²Π½Π΅Π½ΠΈΡ Ρ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠΎΠΌ SD 1 Ρ Π½Π°ΠΏΠΎΠ»Π½ΠΈΡΠ΅Π»Π΅ΠΌ ΠΌΠ΅Π½ΡΡΠ΅ΠΈΜ ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΠΈ.ΠΡΠΎΠ²Π΅Π΄Π΅Π½ΠΎ Π΅ΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½Ρ Π΄ΠΎΡΠ»ΡΠ΄ΠΆΠ΅Π½Π½Ρ Π·ΠΌΡΠ½ΠΈ ΠΆΠΎΡΡΡΠΊΠΎΡΡΡ ΡΠ° ΠΌΠ΅Ρ
Π°Π½ΡΠ·ΠΌΡΠ² ΠΏΠΎΡΠΊΠΎΠ΄ΠΆΠ΅Π½Π½Ρ
ΠΏΡΠΈ Π²ΠΈΠΏΡΠΎΠ±ΡΠ²Π°Π½Π½ΡΡ
Π½Π° Π²ΡΠΎΠΌΡ Π±Π°Π³Π°ΡΠΎΡΠ°ΡΠΎΠ²ΠΈΡ
ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ½ΠΈΡ
ΠΏΠ»Π°ΡΡΠΈΠ½
ΡΠ· Π½Π°ΠΏΠΎΠ²Π½ΡΠ²Π°ΡΠ΅ΠΌ ΡΠ· ΠΏΡΠ½ΠΎΠ²ΡΠ½ΡΠ»ΠΎΠΏΠ»Π°ΡΡΠ°. ΠΠ°Π³Π°ΡΠΎΡΠ°ΡΠΎΠ²Ρ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ½Ρ ΠΏΠ»Π°ΡΡΠΈΠ½ΠΈ Π·
ΠΏΠ΅ΡΠ΅Ρ
ΡΠ΅ΡΠ½ΠΈΠΌΠΈ ΡΠ°ΡΠ°ΠΌΠΈ Π·Ρ ΡΠΊΠ»ΠΎΠ²ΠΎΠ»ΠΎΠΊΠ½Π° ΡΠ° Π΅ΠΏΠΎΠΊΡΠΈΠ΄Π½ΠΎΡ ΡΠΌΠΎΠ»ΠΈ, Π²ΠΈΠ³ΠΎΡΠΎΠ²Π»Π΅Π½Ρ ΠΌΠ΅ΡΠΎΠ΄ΠΎΠΌ
Π²Π°ΠΊΡΡΠΌΠ½ΠΎΠ³ΠΎ Π²ΡΠ΄Π»ΠΈΠ²Ρ, ΠΏΡΠ΄Π΄Π°Π²Π°Π»ΠΈ Π½Π°Π²Π°Π½ΡΠ°ΠΆΠ΅Π½Π½Ρ ΡΡΠΈΡΠΎΡΠΊΠΎΠ²ΠΈΠΌ Π·Π³ΠΈΠ½ΠΎΠΌ. ΠΠΎΡΠ»ΡΠ΄ΠΆΡΠ²Π°Π»ΠΈ
Π΄Π²Π° Π²Π°ΡΡΠ°Π½ΡΠ° ΠΏΠ»Π°ΡΡΠΈΠ½ Π· ΠΎΠ΄Π½ΠΎΡΠΈΠΏΠ½ΠΈΠΌΠΈ Π½Π°ΠΏΠΎΠ²Π½ΡΠ²Π°ΡΠ°ΠΌΠΈ Π· ΠΏΡΠ½ΠΎΠ²ΡΠ½ΡΠ»ΠΎΠΏΠ»Π°ΡΡΠ°
ΡΡΠ·Π½ΠΎΡ ΡΡΠ»ΡΠ½ΠΎΡΡΡ. Π ΠΎΠ·Π³Π»ΡΠ½ΡΡΠΎ Π²ΠΏΠ»ΠΈΠ² ΡΡΠ»ΡΠ½ΠΎΡΡΡ Ρ ΡΠΎΠ²ΡΠΈΠ½ΠΈ Π²Π½ΡΡΡΡΡΠ½ΡΠΎΠ³ΠΎ
ΡΠ°ΡΡ Π½Π°ΠΏΠΎΠ²Π½ΡΠ²Π°ΡΠ° Π½Π° ΠΏΠΎΠ²Π΅Π΄ΡΠ½ΠΊΡ ΡΠ° ΠΏΠΎΡΠΊΠΎΠ΄ΠΆΠ΅Π½Π½Ρ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ°. ΠΠ· Π²ΠΈΠΊΠΎΡΠΈΡΡΠ°Π½Π½ΡΠΌ
Π΄Π²ΠΎΡ
ΡΡΠ·Π½ΠΈΡ
ΠΌΠΎΠ΄Π΅Π»Π΅ΠΉ ΡΠ° ΠΊΡΠΈΡΠ΅ΡΡΡ ΡΠΈΠΊΠ»ΡΡΠ½ΠΎΡ Π΄ΠΎΠ²Π³ΠΎΠ²ΡΡΠ½ΠΎΡΡΡ ΠΏΠΎΠ±ΡΠ΄ΠΎΠ²Π°Π½ΠΎ
ΠΊΡΠΈΠ²Ρ Π²ΡΠΎΠΌΠ»Π΅Π½ΠΎΡΡΡ Ρ ΠΏΡΠΎΠ²Π΅Π΄Π΅Π½ΠΎ ΡΡ
ΠΏΠΎΡΡΠ²Π½ΡΠ»ΡΠ½ΠΈΠΉ Π°Π½Π°Π»ΡΠ· ΡΠ· Π²ΡΠ΄ΠΎΠΌΠΈΠΌΠΈ Π»ΡΡΠ΅ΡΠ°ΡΡΡΠ½ΠΈΠΌΠΈ
Π΄Π°Π½ΠΈΠΌΠΈ. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΠΎ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡ SD 2 Π· Π½Π°ΠΏΠΎΠ²Π½ΡΠ²Π°ΡΠ΅ΠΌ Π²Π΅Π»ΠΈΠΊΠΎΡ ΡΡΠ»ΡΠ½ΠΎΡΡΡ
ΠΌΠ°Ρ Π±ΡΠ»ΡΡ Π²ΠΈΡΠΎΠΊΡ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊΠΈ ΡΡΠ°ΡΠΈΡΠ½ΠΎΡ ΠΌΡΡΠ½ΠΎΡΡΡ Ρ ΡΡΡΠΉΠΊΠΎΡΡΡ ΡΠ° ΡΡΠΎΠΌΠ½ΠΎΡ
ΠΌΡΡΠ½ΠΎΡΡΡ ΠΏΠΎΡΡΠ²Π½ΡΠ½ΠΎ Π· ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠΎΠΌ SD 1 ΡΠ· Π½Π°ΠΏΠΎΠ²Π½ΡΠ²Π°ΡΠ΅ΠΌ ΠΌΠ΅Π½ΡΠΎΡ ΡΡΠ»ΡΠ½ΠΎΡΡΡ.The analysis o f stiffness degradation and the
identification o f damage mechanisms during and
after fatigue tests of sandwich panels with PVC
foam cores have been performed. The sandwich
panels with cross-ply laminates skins made of
glass fiber and epoxy resin were manufactured
by vacuum moulding and subjected to three-point
bending tests. Two PVC cores of similar type but
with differing densities were investigated. The effect
o f core density and thickness on the damage
behavior was highlighted. Using the cyclic life
criterion, fatigue curves were plotted according
to two models and compared with those o f the literature.
It has been demonstrated that the
sandwich SD 2, with the higher core density, withstands
a higher load and possesses greater rigidity
in static tests, combined with an enhanced
fatigue resistance when compared to sandwich
SD 1 which has a lower core density
Experimental Analysis of Behavior and Damage of Sandwich Composite Materials in Three-Point Bending. Part 2. Fatigue Test Results and Damage Mechanisms
ΠΡΠΏΠΎΠ»Π½Π΅Π½Ρ ΡΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΡΠ΅ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΡ ΠΆΠ΅ΡΡΠΊΠΎΡΡΠΈ ΠΈ ΠΌΠ΅Ρ
Π°Π½ΠΈΠ·ΠΌΠΎΠ² ΠΏΠΎΠ²ΡΠ΅ΠΆΒΠ΄Π΅Π½ΠΈΡ ΠΏΡΠΈ ΡΡΡΠ°Π»ΠΎΡΡΠ½ΡΡ
ΠΈΡΠΏΡΡΠ°Π½ΠΈΡΡ
ΠΌΠ½ΠΎΠ³ΠΎΡΠ»ΠΎΠΈΜΠ½ΡΡ
ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ½ΠΈΡ
ΠΏΠ»Π°ΡΡΠΈΠ½ Ρ Π½Π°ΠΏΠΎΠ»Π½ΠΈΡΠ΅Π»Π΅ΠΌ ΠΈΠ· ΠΏΠ΅Π½ΠΎΠ²ΠΈΠ½ΠΈΠ»ΠΎΠΏΠ»Π°ΡΡΠ°. ΠΠ½ΠΎΠ³ΠΎΡΠ»ΠΎΠΈΜΠ½ΡΠ΅ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ½ΡΠ΅ ΠΏΠ»Π°ΡΡΠΈΠ½Ρ Ρ ΠΏΠ΅ΡΠ΅ΠΊΡΠ΅ΡΡΠ½ΡΠΌΠΈ ΡΠ»ΠΎΡΠΌΠΈ ΠΈΠ· ΡΡΠ΅ΠΊΠ»ΠΎΒ Π²ΠΎΠ»ΠΎΠΊΠ½Π° ΠΈ ΡΠΏΠΎΠΊΡΠΈΠ΄Π½ΠΎΠΈΜ ΡΠΌΠΎΠ»Ρ, ΠΈΠ·Π³ΠΎΡΠΎΠ²Π»Π΅Π½Π½ΡΠ΅ ΠΌΠ΅ΡΠΎΠ΄ΠΎΠΌ Π²Π°ΠΊΡΡΠΌΠ½ΠΎΠΈΜ ΠΎΡΠ»ΠΈΠ²ΠΊΠΈ, ΠΏΠΎΠ΄Π²Π΅ΡΠ³Π°Π»ΠΈ Π½Π°Π³ΡΡΒΠΆΠ΅Π½ΠΈΡ ΡΡΠ΅Ρ
ΡΠΎΡΠ΅ΡΠ½ΡΠΌ ΠΈΠ·Π³ΠΈΠ±ΠΎΠΌ. ΠΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π»ΠΈ Π΄Π²Π° Π²Π°ΡΠΈΠ°Π½ΡΠ° ΠΏΠ»Π°ΡΡΠΈΠ½ Ρ ΠΎΠ΄Π½ΠΎΡΠΈΠΏΠ½ΡΠΌΠΈ Π½Π°ΠΏΠΎΠ»ΒΠ½ΠΈΡΠ΅Π»ΡΠΌΠΈ ΠΈΠ· ΠΏΠ΅Π½ΠΎΠ²ΠΈΠ½ΠΈΠ»ΠΎΠΏΠ»Π°ΡΡΠ° ΡΠ°Π·Π»ΠΈΡΠ½ΠΎΠΈΜ ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΠΈ. Π Π°ΡΡΠΌΠΎΡΡΠ΅Π½ΠΎ Π²Π»ΠΈΡΠ½ΠΈΠ΅ ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΠΈ ΠΈ ΡΠΎΠ»ΡΠΈΠ½Ρ Π²Π½ΡΡΡΠ΅Π½Π½Π΅Π³ΠΎ ΡΠ»ΠΎΡ Π½Π°ΠΏΠΎΠ»Π½ΠΈΡΠ΅Π»Ρ Π½Π° ΠΏΠΎΠ²Π΅Π΄Π΅Π½ΠΈΠ΅ ΠΈ ΠΏΠΎΠ²ΡΠ΅ΠΆΠ΄Π΅Π½ΠΈΠ΅ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ°. Π‘ ΠΈΡΠΏΠΎΠ»ΡΒΠ·ΠΎΠ²Π°Π½ΠΈΠ΅ΠΌ Π΄Π²ΡΡ
ΡΠ°Π·Π»ΠΈΡΠ½ΡΡ
ΠΌΠΎΠ΄Π΅Π»Π΅ΠΈΜ ΠΈ ΠΊΡΠΈΡΠ΅ΡΠΈΡ ΡΠΈΠΊΠ»ΠΈΡΠ΅ΡΠΊΠΎΠΈΜ Π΄ΠΎΠ»Π³ΠΎΠ²Π΅ΡΠ½ΠΎΡΡΠΈ ΠΏΠΎΡΡΡΠΎΠ΅Π½Ρ ΠΊΡΠΈΠ²ΡΠ΅ ΡΡΡΠ°Π»ΠΎΡΡΠΈ ΠΈ Π²ΡΠΏΠΎΠ»Π½Π΅Π½ ΠΈΡ
ΡΡΠ°Π²Π½ΠΈΡΠ΅Π»ΡΠ½ΡΠΈΜ Π°Π½Π°Π»ΠΈΠ· Ρ ΠΈΠΌΠ΅ΡΡΠΈΠΌΠΈΡΡ Π»ΠΈΡΠ΅ΡΠ°ΡΡΡΠ½ΡΠΌΠΈ Π΄Π°Π½Π½ΡΠΌΠΈ. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡ SD 2 Ρ Π½Π°ΠΏΠΎΠ»Π½ΠΈΡΠ΅Π»Π΅ΠΌ Π±ΠΎΠ»ΡΡΠ΅ΠΈΜ ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΠΈ ΠΎΠ±Π»Π°Π΄Π°Π΅Ρ Π±ΠΎΠ»Π΅Π΅ Π²ΡΡΠΎΠΊΠΈΠΌΠΈ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊΠ°ΠΌΠΈ ΡΡΠ°ΡΠΈΡΠ΅ΡΠΊΠΎΠΈΜ ΠΏΡΠΎΡΠ½ΠΎΡΡΠΈ ΠΈ ΡΡΡΠΎΠΈΜΡΠΈΠ²ΠΎΡΡΠΈ, Π° ΡΠ°ΠΊΠΆΠ΅ ΡΡΡΠ°Π»ΠΎΡΡΠ½ΠΎΠΈΜ ΠΏΡΠΎΡΒΠ½ΠΎΡΡΠΈ ΠΏΠΎ ΡΡΠ°Π²Π½Π΅Π½ΠΈΡ Ρ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠΎΠΌ SD 1 Ρ Π½Π°ΠΏΠΎΠ»Π½ΠΈΡΠ΅Π»Π΅ΠΌ ΠΌΠ΅Π½ΡΡΠ΅ΠΈΜ ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΠΈ.ΠΡΠΎΠ²Π΅Π΄Π΅Π½ΠΎ Π΅ΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½Ρ Π΄ΠΎΡΠ»ΡΠ΄ΠΆΠ΅Π½Π½Ρ Π·ΠΌΡΠ½ΠΈ ΠΆΠΎΡΡΡΠΊΠΎΡΡΡ ΡΠ° ΠΌΠ΅Ρ
Π°Π½ΡΠ·ΠΌΡΠ² ΠΏΠΎΡΠΊΠΎΠ΄ΠΆΠ΅Π½Π½Ρ
ΠΏΡΠΈ Π²ΠΈΠΏΡΠΎΠ±ΡΠ²Π°Π½Π½ΡΡ
Π½Π° Π²ΡΠΎΠΌΡ Π±Π°Π³Π°ΡΠΎΡΠ°ΡΠΎΠ²ΠΈΡ
ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ½ΠΈΡ
ΠΏΠ»Π°ΡΡΠΈΠ½
ΡΠ· Π½Π°ΠΏΠΎΠ²Π½ΡΠ²Π°ΡΠ΅ΠΌ ΡΠ· ΠΏΡΠ½ΠΎΠ²ΡΠ½ΡΠ»ΠΎΠΏΠ»Π°ΡΡΠ°. ΠΠ°Π³Π°ΡΠΎΡΠ°ΡΠΎΠ²Ρ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ½Ρ ΠΏΠ»Π°ΡΡΠΈΠ½ΠΈ Π·
ΠΏΠ΅ΡΠ΅Ρ
ΡΠ΅ΡΠ½ΠΈΠΌΠΈ ΡΠ°ΡΠ°ΠΌΠΈ Π·Ρ ΡΠΊΠ»ΠΎΠ²ΠΎΠ»ΠΎΠΊΠ½Π° ΡΠ° Π΅ΠΏΠΎΠΊΡΠΈΠ΄Π½ΠΎΡ ΡΠΌΠΎΠ»ΠΈ, Π²ΠΈΠ³ΠΎΡΠΎΠ²Π»Π΅Π½Ρ ΠΌΠ΅ΡΠΎΠ΄ΠΎΠΌ
Π²Π°ΠΊΡΡΠΌΠ½ΠΎΠ³ΠΎ Π²ΡΠ΄Π»ΠΈΠ²Ρ, ΠΏΡΠ΄Π΄Π°Π²Π°Π»ΠΈ Π½Π°Π²Π°Π½ΡΠ°ΠΆΠ΅Π½Π½Ρ ΡΡΠΈΡΠΎΡΠΊΠΎΠ²ΠΈΠΌ Π·Π³ΠΈΠ½ΠΎΠΌ. ΠΠΎΡΠ»ΡΠ΄ΠΆΡΠ²Π°Π»ΠΈ
Π΄Π²Π° Π²Π°ΡΡΠ°Π½ΡΠ° ΠΏΠ»Π°ΡΡΠΈΠ½ Π· ΠΎΠ΄Π½ΠΎΡΠΈΠΏΠ½ΠΈΠΌΠΈ Π½Π°ΠΏΠΎΠ²Π½ΡΠ²Π°ΡΠ°ΠΌΠΈ Π· ΠΏΡΠ½ΠΎΠ²ΡΠ½ΡΠ»ΠΎΠΏΠ»Π°ΡΡΠ°
ΡΡΠ·Π½ΠΎΡ ΡΡΠ»ΡΠ½ΠΎΡΡΡ. Π ΠΎΠ·Π³Π»ΡΠ½ΡΡΠΎ Π²ΠΏΠ»ΠΈΠ² ΡΡΠ»ΡΠ½ΠΎΡΡΡ Ρ ΡΠΎΠ²ΡΠΈΠ½ΠΈ Π²Π½ΡΡΡΡΡΠ½ΡΠΎΠ³ΠΎ
ΡΠ°ΡΡ Π½Π°ΠΏΠΎΠ²Π½ΡΠ²Π°ΡΠ° Π½Π° ΠΏΠΎΠ²Π΅Π΄ΡΠ½ΠΊΡ ΡΠ° ΠΏΠΎΡΠΊΠΎΠ΄ΠΆΠ΅Π½Π½Ρ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ°. ΠΠ· Π²ΠΈΠΊΠΎΡΠΈΡΡΠ°Π½Π½ΡΠΌ
Π΄Π²ΠΎΡ
ΡΡΠ·Π½ΠΈΡ
ΠΌΠΎΠ΄Π΅Π»Π΅ΠΉ ΡΠ° ΠΊΡΠΈΡΠ΅ΡΡΡ ΡΠΈΠΊΠ»ΡΡΠ½ΠΎΡ Π΄ΠΎΠ²Π³ΠΎΠ²ΡΡΠ½ΠΎΡΡΡ ΠΏΠΎΠ±ΡΠ΄ΠΎΠ²Π°Π½ΠΎ
ΠΊΡΠΈΠ²Ρ Π²ΡΠΎΠΌΠ»Π΅Π½ΠΎΡΡΡ Ρ ΠΏΡΠΎΠ²Π΅Π΄Π΅Π½ΠΎ ΡΡ
ΠΏΠΎΡΡΠ²Π½ΡΠ»ΡΠ½ΠΈΠΉ Π°Π½Π°Π»ΡΠ· ΡΠ· Π²ΡΠ΄ΠΎΠΌΠΈΠΌΠΈ Π»ΡΡΠ΅ΡΠ°ΡΡΡΠ½ΠΈΠΌΠΈ
Π΄Π°Π½ΠΈΠΌΠΈ. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΠΎ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡ SD 2 Π· Π½Π°ΠΏΠΎΠ²Π½ΡΠ²Π°ΡΠ΅ΠΌ Π²Π΅Π»ΠΈΠΊΠΎΡ ΡΡΠ»ΡΠ½ΠΎΡΡΡ
ΠΌΠ°Ρ Π±ΡΠ»ΡΡ Π²ΠΈΡΠΎΠΊΡ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊΠΈ ΡΡΠ°ΡΠΈΡΠ½ΠΎΡ ΠΌΡΡΠ½ΠΎΡΡΡ Ρ ΡΡΡΠΉΠΊΠΎΡΡΡ ΡΠ° ΡΡΠΎΠΌΠ½ΠΎΡ
ΠΌΡΡΠ½ΠΎΡΡΡ ΠΏΠΎΡΡΠ²Π½ΡΠ½ΠΎ Π· ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠΎΠΌ SD 1 ΡΠ· Π½Π°ΠΏΠΎΠ²Π½ΡΠ²Π°ΡΠ΅ΠΌ ΠΌΠ΅Π½ΡΠΎΡ ΡΡΠ»ΡΠ½ΠΎΡΡΡ.The analysis o f stiffness degradation and the
identification o f damage mechanisms during and
after fatigue tests of sandwich panels with PVC
foam cores have been performed. The sandwich
panels with cross-ply laminates skins made of
glass fiber and epoxy resin were manufactured
by vacuum moulding and subjected to three-point
bending tests. Two PVC cores of similar type but
with differing densities were investigated. The effect
o f core density and thickness on the damage
behavior was highlighted. Using the cyclic life
criterion, fatigue curves were plotted according
to two models and compared with those o f the literature.
It has been demonstrated that the
sandwich SD 2, with the higher core density, withstands
a higher load and possesses greater rigidity
in static tests, combined with an enhanced
fatigue resistance when compared to sandwich
SD 1 which has a lower core density
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