Architecture Civil Engineering Environment 

About: Architecture Civil Engineering Environment is an academic journal published by Exeley Inc. The journal publishes majorly in the area(s): Engineering & Architecture. It has an ISSN identifier of 1899-0142. It is also open access. Over the lifetime, 683 publications have been published receiving 2303 citations. The journal is also known as: ACEE.

The influence of the strain rate on the strength of concrete taking into account the experimental techniques

Abstract: Based on extensive literature review the behaviour of concrete under wide range of compressive and tensile strain rates is presented. The dynamic compressive strength of concrete can achieve the value of DIF (dynamic increase factor) equal about 3.5, and the dynamic tensile strength even 13. However, the strain rate response of concrete in tension and compression in all range of strain rate differs much. In compression strain rate sensitivity should be investigated in two domains, because of the shift of test results. The reason of division is probably connected with influence of the method of testing and especially with the specimen shape and size. The article presents also the strain rate sensitivity of new types of cement-based materials, like RPC, which appears not to differ much from the sensitivity of normal concrete.

Biodeterioration of concrete

Abstract: A b s t r a c t Concrete structures belong to these usually considered as indestructible because of their longer service life as compared with the most constructional products. However, they can get destroyed for a variety of reasons including these of biologi cal origin. Many architectural and other building structures undergo biodeterioration when exposed to contact with soil, water, and sewage, as well as food, agricultural products and waste materials. This review explains the effect of some bio genic corrosive substances produced by the microorganisms on concrete. S t r e s z c z e n i e Konstrukcje betonowe nalezą do tych, ktore zazwyczaj są uwazane jako niezniszczalne ze wzgledu na ich dluzszy okres uzytkowania w porownaniu z wiekszością wyrobow konstrukcyjnych. Jednak mogą one ulegac zniszczeniu z roznych przy czyn, wlączając te pochodzenia biologicznego. Wiele budowli architektonicznych i innych konstrukcji budowlanych ulega biodeterioracji w przypadku narazenia na kontakt z glebą, wodą i ściekami, jak rowniez produktami i odpadami zywnoś ciowymi i pochodzenia rolniczego. Ten przegląd wyjaśnia dzialanie na beton niektorych biogennych substancji korozyjnych produkowanych przez mikroorganizmy.

Mechanical properties of concrete subjected to high temperature

Abstract: The paper discusses key processes and phenomena occurring in concrete subjected to elevated temperatures. It refers to main pre-requisites of the Eurocode model (EN 1992-1-2) discussing mechanical properties of heated concrete and it dis cusses the behaviour of concrete in reinforced concrete structures exposed to fire, which does not necessarily have to be fully compliant with expectations based on standard guidelines. The compression stress, although not excessively high, inhibits the reduction of the strength of concrete when heated. The strength of concrete heated to high temperature and subse quently cooled down is lower than its strength in high temperature. In the result of concrete transient creep, the internal forces of a concrete structure or the stresses in the cross-section of an element may be redistributed. Ignoring transient creep in concrete while performing advanced computational analyses may generate inadequate results. Thermal spalling of heated concrete may result in sudden disclosure of reinforcing bars of elements or sudden reduction of their cross-section. Streszczenie W artykule omowiono najwazniejsze procesy i zjawiska wystepujące w betonie podczas dzialania na niego wysokiej temperatury. Przytoczono najwazniejsze zalozenia Eurokodowskiego (EN 1992-1-2) modelu opisującego cechy mechaniczne ogrze wanego betonu, a nastepnie zwrocono uwage, ze zachowanie sie betonu w konstrukcjach zelbetowych narazonych na dzialanie pozaru nie zawsze musi byc w pelni zgodne z tym, co mozna przewidywac na podstawie wytycznych normowych. Wystepowanie w betonie niezbyt duzych naprezen ściskających powoduje powstrzymanie pogarszania sie wytrzymalości betonu podczas ogrzewania. Wytrzymalośc betonu rozgrzanego do wysokiej temperatury, jest po jego ochlodzeniu nizsza od wystepującej w wysokiej temperaturze. Na skutek pelzania termicznego betonu moze wystąpic redystrybucja sil wewnetrznych w konstrukcji lub redystrybucja naprezen w przekroju elementu. Nieuwzglednienie zjawiska pelzania ter micznego betonu w zaawansowanych analizach obliczeniowych moze byc przyczyną uzyskania nieadekwatnych wynikow obliczen. Odpryskiwanie betonu podczas ogrzewania moze prowadzic do gwaltownego odsloniecia zbrojenia elementow zel betowych lub do gwaltownego zmniejszenia ich przekroju.

Biogas purification by sorption techniques

Abstract: Biomass is more and more frequently used as a raw material to produce biomethane and synthetic liquid fuel. The increasing energy problems in Poland and the promotion of electrical power production from renewable sources attach a special significance to biogas. The potential for agricultural biogas production in Poland equals the amount of biogas imported currently from Russia. Meeting Poland’s obligations stated in the National Plan of Waste Management also necessitates the implementation of digestion techniques of selected organic waste. However, the biogas needs to be treated prior to its use. Basic impurities present in biogas include: carbon dioxide, hydrogen sulfide, nitrogen, oxygen, ammonia, chlorinated organic matter, silanes, siloxanes [29, 30], volatile phosphorus substances and other volatile trace compounds. The techniques of carbon dioxide and hydrogen sulfide removal from biogas are very important for many reasons. After carbon dioxide, hydrogen sulfide and moisture are removed from biogas, it can be compressed and used as CNG, especially during the operation of agricultural and landfill biogas plants outside the peak time of power consumption. Further removal of the impurities makes the biogas suitable for gas piping. The removal of trace impurities, notably phosphorus compounds, enables biogas to be used in the production of hydrogen for fuel cells [25-28, 37]. The real significance of biogas is proved by the fact that currently there are about 5000 agricultural biogas plants in Germany and by 2020 the German government is planning to replace 6% of natural gas with biogas produced through digestion [1]. About several hundred agricultural biogas plants operate in Austria BIOGAS PURIFICATION BY SORPTION TECHNIQUES