The effect of elevated temperature on the lightweight concrete containing waste PET aggregate

In this study, the effect of waste PET as lightweight aggregate (WPLA) replacement with conventional aggregate on the some physical and mechanical properties and residual compressive strength of concrete was investigated. For this purpose, five different mixtures were prepared (the reference mixture and four WPLA mixtures including 30%, 40%, 50% and 60% waste PET aggregate by volume). The fresh and dry unit weights, compressive strengths, flexural-tensile strengths, water absorption and porosity ratios of the mixtures were measured. In addition the specimens exposed to elevated temperatures at 150, 300 and 450 °C and the residual compressive strengths were measured. Test results indicated that the unit weight, compressive strength and flexural-tensile strength of the specimens decreased as the amount of WPLA increased in concrete. After exposing to elevated temperature, WPLA mixtures retained their structural integrity and compressive strengths at 150 °C and 300 °C. However there was a significant decrease in the residual compressive strength values of WPLA mixtures at 450 °C

Examination of Passive Fire Safety measures in High Buildings: A Research in Niğde

Inthisstudy, passive fire safetymeasures in someresidencebuildingexamples in Niğde wereevaluatedaccordingtotheTurkishRegulation on Fire Protection(BYKHY 2007). Withinthescope of thestudy, fivebuildingbuiltbetween 2016 and 2017 andfallingintothehighbuildingclasswereexamined. As a result of theevaluation, it is seenthatthepassive fire safetymeasurestaken in thebuildingsexamined in thescope of thestudyaregenerally in accordancewiththeprinciples of TurkishRegulation on Fire Protection. Insome of theexamplesexamined, it wasdeterminedthatthematerialsused in theroofswere not in accordancewiththeregulation. Anotherimportant problem encountered in all of theexaminedbuildings is thatthenumber of pressurized fire escapestairswith fire safetyhall is not in accordancewiththeprinciples of regulation. It is consideredthat, in thedesignprocess, iftheprovisions of theregulationaretakenintoaccountandthedetails of thematerialto be used in theprojectareindicated, theshortcomings in practice can be avoided.Bu çalışmada, Niğde’de bulunan bazı konut örneklerindeki pasif yangın güvenlik önlemleri, Binaların Yangından Korunması Hakkında Yönetmelik (BYKHY 2007) esaslarına göre değerlendirilmiştir. Çalışma kapsamında 2016-2017 yılları arasında yapılmış olan ve yüksek bina sınıfına giren beş konut binası incelenmiştir. Değerlendirme sonucunda, çalışma kapsamında incelenen bina örneklerinde alınan pasif yangın güvenlik önlemlerinin genel olarak BYKHY esaslarına uygun olduğu görülmektedir. İncelenen bazı örneklerde çatılarda kullanılan malzemelerin yönetmeliğe uygun olmadığı tespit edilmiştir. İncelenen örneklerin tamamında görülen diğer önemli bir sorun ise yangın güvenlik holü olan ve basınçlandırılan yangın merdiveni sayısının BYKHY esaslarına uygun olmamasıdır. Tasarım aşamasında yönetmelik hükümlerinin dikkate alınması ve projede kullanılacak malzeme detaylarının belirtilmesi durumunda, uygulamada görülen eksikliklerin önlenebileceği düşünülmektedir

The effect of elevated temperature on the lightweight concrete containing waste PET aggregate

In this study, the effect of waste PET as lightweight aggregate (WPLA) replacement with conventional aggregate on the some physical and mechanical properties and residual compressive strength of concrete was investigated. For this purpose, five different mixtures were prepared (the reference mixture and four WPLA mixtures including 30%, 40%, 50% and 60% waste PET aggregate by volume). The fresh and dry unit weights, compressive strengths, flexural-tensile strengths, water absorption and porosity ratios of the mixtures were measured. In addition the specimens exposed to elevated temperatures at 150, 300 and 450 °C and the residual compressive strengths were measured. Test results indicated that the unit weight, compressive strength and flexural-tensile strength of the specimens decreased as the amount of WPLA increased in concrete. After exposing to elevated temperature, WPLA mixtures retained their structural integrity and compressive strengths at 150 °C and 300 °C. However there was a significant decrease in the residual compressive strength values of WPLA mixtures at 450 °C

The effect of fine material amount on optimum water content of roller compacted concrete

In this study the effect of fine material amount on the optimum water content of roller compacted concrete (RCC) was investigated. The fine aggregate was replaced with calcite which maximum particle size was 63 μ, in amount of 0%, 2%, 4%, 6%, 10% and 14% by weight of total aggregate. Six different mixtures were prepared in the study. The optimum water contents of the mixtures were determined by using modified proctor test. Optimum water content, maximum dry unit weight and maximum fresh unit weight of produced specimens were measured. Optimum water content of specimens decreased depending on increasing fine aggregate amount, however these values increased after a limit value. Maximum fresh and dry unit weights of specimens increased depending on increasing fine aggregate amount, however after a limit value the fresh and dry weights of specimens decreased

The effect of fine material amount on optimum water content of roller compacted concrete

In this study the effect of fine material amount on the optimum water content of roller compacted concrete (RCC) was investigated. The fine aggregate was replaced with calcite which maximum particle size was 63 μ, in amount of 0%, 2%, 4%, 6%, 10% and 14% by weight of total aggregate. Six different mixtures were prepared in the study. The optimum water contents of the mixtures were determined by using modified proctor test. Optimum water content, maximum dry unit weight and maximum fresh unit weight of produced specimens were measured. Optimum water content of specimens decreased depending on increasing fine aggregate amount, however these values increased after a limit value. Maximum fresh and dry unit weights of specimens increased depending on increasing fine aggregate amount, however after a limit value the fresh and dry weights of specimens decreased

Investigation of Production of Brick with Waste Coal Powder Additive

Wastes in coal quarries and coal power plants are significant issues. Coal washing plant tailings as waste coal powder is one of these issues. Today, their ecological and economical utilization, control and management are of main subjects for ongoing researches throughout the world. On the other hand, researchers still carry out intense investigations on the production of lightweight and sustainable products for construction industry. In Turkey, approximately 20 coal mines and 1 coal power plant do have coal washing plant. In this study, waste coal powder obtained from Soma, Manisa were replaced with clay obtained from Niğde Kolsuz Region in amount of 10%, 20% and 30% by weight and fired at 1000 ° C to produce bricks. Unit weight, compressive strength, flexural tensile strength and water absorption tests were carried out on the samples. Experimental results showed that the addition of coal powder at the replacement ratio of 10% increased the compressive strength and flexural tensile strength of the samples. Use of produced samples in the construction industry will provide produce of high strength bricks of developed features besides contributing to the utilization of coal powder by recycling

Investigation of engineering properties of normal and high strength fly ash based geopolymer and alkali-activated slag concrete compared to ordinary Portland cement concrete

Fly ash-based geopolymer (FAGP) and alkali-activated slag (AAS) concrete are produced by mixing alkaline solutions with aluminosilicate materials. As the FAGP and AAS concrete are free of Portland cement, they have a low carbon footprint and consume low energy during the production process. This paper compares the engineering properties of normal strength and high strength FAGP and AAS concrete with OPC concrete. The engineering properties considered in this study included workability, dry density, ultrasonic pulse velocity (UPV), compressive strength, indirect tensile strength, flexural strength, direct tensile strength, and stress-strain behaviour in compression and direct tension. Microstructural observations using scanning electronic microscopy (SEM) are also presented. It was found that the dry density and UPV of FAGP and AAS concrete were lower than those of OPC concrete of similar compressive strength. The tensile strength of FAGP and AAS concrete was comparable to the tensile strength of OPC concrete when the compressive strength of the concrete was about 35 MPa (normal strength concrete). However, the tensile strength of FAGP and AAS concrete was higher than the tensile strength of OPC concrete when the compressive strength of concrete was about 65 MPa (high strength concrete). The modulus of elasticity of FAGP and AAS concrete in compression and direct tension was lower than the modulus of elasticity of OPC concrete of similar compressive strength. The SEM results indicated that the microstructures of FAGP and AAS concrete were more compact and homogeneous than the microstructures of OPC concrete at 7 days, but less compact and homogeneous than the microstructures of OPC concrete at 28 days for the concrete of similar compressive strength