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This article aimed to study the effects of chitosan fiber and a newly modifying agent, based on organosolv lignin, on mechanical and thermal performances and the enzymatic degradation of PLA/chitosan biocomposites. A newly modifying agent based on polyacrylic acid-grafted organosolv lignin (PAA-g-OSL) was synthesized via free radical copolymerization using t-butyl peroxide as the initiator. The biocomposites were prepared using an internal mixer and the hot-pressed method at various fiber loadings. The results demonstrate that the addition of chitosan fiber into PLA biocomposites remarkably decreases tensile strength and elongation at break. However, it improves the Young’s modulus. The modified biocomposites clearly demonstrat an improvement in tensile strength by approximately 20%, with respect to the unmodified ones, upon the presence of PAA-g-OSL. Moreover, the thermal stability of the modified biocomposites was enhanced significantly, indicating the effectiveness of the thermal protective barrier of the lignin’s aromatic structure belonging to the modifying agent during pyrolysis. In addition, a slower biodegradation rate was exhibited by the modified biocomposites, relative to the unmodified ones, that confirms the positive effects of their improved interfacial interaction, resulting in a decreased area that was degraded through enzyme hydrolysis.

Summary. The problem of prediction of the service life of asphalt concrete surface constructed with modified asphalt concrete application onto a traffic lane is examined. Asphalt concrete behaviour in road surface under the traffic loads was analysed. There were shown The results of experiments and their mathematical analysis of the assessment of standard and modified cold asphalt concrete fatigue life on road surface were shown. The service life of an asphalt concrete surface covered with standard and modified cold asphalt concrete is examined. The prediction has been received with an account of stress relaxation processes in asphalt concrete pavement and unevenness of traffic load application.

Summary. The problem of prediction of the service life of asphalt concrete surface constructed with modified asphalt concrete application onto a traffic lane is examined. Asphalt concrete behaviour in road surface under the traffic loads was analysed. There were shown The results of experiments and their mathematical analysis of the assessment of standard and modified cold asphalt concrete fatigue life on road surface were shown. The service life of an asphalt concrete surface covered with standard and modified cold asphalt concrete is examined. The prediction has been received with an account of stress relaxation processes in asphalt concrete pavement and unevenness of traffic load application.

Purpose. To study various additives of a domestic production and to estimate expediency of their use for products of transport construction. Methodology . The study was conducted by introducing a superplasticizer and active mineral additives Findings. The complex additive should include effective superplasticizing admix, as well as additives which operate stiffening and hardening kinetics, air retaining substances and defoaming agents, dispersion and fine-dispersion mineral fillers. In recent years organo-mineral modifiers such as superplasticizer - an active mineral additive (microsilica, metakaolin, ash) obtained a wide circulation. Originality. The impact of various additives on the concrete quality is studied. It is found out that the complex additive PLKP deserves the special attention because it allows producing a concrete of very high durability and is recommended for use in railroad ties. Thus, the introduction of additives in the concrete can significantly increase the durability and reliability of concrete products. Practical value. Results of the research can be used to improve the reliability and durability of concrete structures. This calls for further researches on the selection of the concrete mixture with complex additive PLKP, as well as adding the active mineral components .

Purpose. To study various additives of a domestic production and to estimate expediency of their use for products of transport construction. Methodology. The study was conducted by introducing a superplasticizer and active mineral additives Findings. The complex additive should include effective superplasticizing admix, as well as additives which operate stiffening and hardening kinetics, air retaining substances and defoaming agents, dispersion and fine-dispersion mineral fillers. In recent years organo-mineral modifiers such as superplasticizer - an active mineral additive (microsilica, metakaolin, ash) obtained a wide circulation. Originality. The impact of various additives on the concrete quality is studied. It is found out that the complex additive PLKP deserves the special attention because it allows producing a concrete of very high durabilityand is recommended for use in railroad ties. Thus, the introduction of additives in the concrete can significantly increase the durability and reliability of concrete products. Practical value. Results of the research can be used to improve the reliability and durability of concrete structures. This calls for further researches on the selection of the concrete mixture with complex additive PLKP, as well as adding the active mineral components., Цель. Рассмотреть различные добавки отечественного производства и оценить целесообразность их использования для изделий транспортного строительства. Методика. Исследование проводилось путем введения суперпластификатора и активной минеральной добавки. Результаты. В комплексную добавку должен входить эффективный суперпластификатор, а также могут входить добавки, которые управляют кинетикой схватывания и твердения, воздухововлекающие добавки и пеногасители, дисперсные и тонкодисперсные минеральные наполнители. В последние годы широкое распространение получили органо-минеральные модификаторы типа суперпластификатор – активная минеральная добавка (микрокремнезем, метакаолин, зола). Научная новизна. Исследовано влияние различных добавок на качество бетона. Установлено, что комплексная добавка ПЛПК заслуживает особого внимания, поскольку она позволяет получать бетоны с очень высокой долговечностью и рекомендуется для применения в железнодорожных шпалах. Таким образом, введением добавок в состав бетона можно существенно повысить долговечность и надежность железобетонных изделий. Практическая значимость. Результаты исследования могут использоваться для повышения надежности и долговечности бетонных конструкций. Это требует дальнейших исследований по подбору состава бетона с комплексной добавкой ПЛКП и добавлением активных минеральных компонентов., Мета. Розглянути різноманітні добавки вітчизняного виробництва і оцінити доцільність їх використання для виробів транспортного будівництва. Методика. Дослідження проводилося шляхом введення суперпластифікатора та активної мінеральної добавки. Результати. В комплексну добавку повинен входити ефективний суперпластифікатор, а також можуть входити добавки, які керують кінетикою тужавлення і твердіння, повітровтягуючі добавки і піногасники, дисперсні і тонкодисперсні мінеральні наповнювачі. В останні роки широке розповсюдження здобули органо-мінеральні модифікатори типу суперпластифікатор – активна мінеральна добавка (мікрокремнезем, метакаолін, зола). Наукова новизна. Досліджено вплив різноманітних добавок на якість бетону. Встановлено, що комплексна добавка ПЛПК заслуговує особливої уваги, оскільки дозволяє отримувати бетони з дуже високими характеристиками довговічності і рекомендується для застосування в залізничних шпалах. Таким чином, введенням добавок до складу бетону можна суттєво підвищити довговічність і надійність залізобетонних виробів. Практична значимість. Результати дослідження можуть використовуватися для підвищення надійності і довговічності бетонних конструкцій. Це потребує подальших досліджень з підбору складу бетону з комплексною добавкою ПЛКП і додаванням активних мінеральних компонентів.