Investigation of the Effects of Nano Silica Particles and Zeolite on the Mechanical Strengths of Metakaolin-Based Geopolymer Concrete

Due to its unique qualities, concrete is the most extensively utilized substance in the construction sector after water. However, because one ton of Portland cement produces about one ton of CO2, the Portland cement manufacturing process has considerable disadvantages. As a result, an alternative to Portland cement appears to be required. Geopolymer is a new and environmentally friendly cementitious material that can be used in place of Portland cement. Chemically and mechanically, geopolymer concrete outperforms traditional concrete. The weight ratio of water to dry matter used in polymerization, as well as the weight ratio of sodium silicate to NaOH solution, have an impact on the compressive strength of geopolymer concrete. As a result, additional research into these variables appeared to be necessary. This paper specifically looked at how nanosilica and zeolite affected the mechanical strength of metakaolin-based geopolymer concrete. Nanosilica was added to metakaolin-based geopolymer concrete to improve mechanical characteristics. Furthermore, using zeolite in a metakaolin-based aluminosilicate source lowers the mechanical strength of geopolymer concrete while also lowering the cost. The optimal weight ratios for polymerization water to dry matter and sodium silicate solution to NaOH solution were 0.4741 and 1.5, respectively, resulting in maximum compressive pressures of 3, 7, and 28 days

Effect of gelatin powder, almond shell, and recycled aggregates on chemical and mechanical properties of conventional concrete

The objective of the research is to study the effect of different additives on the conventional concrete. In this term, three types of materials have been added to the concrete: gelatin powder as the binder, recycled aggregates, and almond shell as the fine and coarse aggregates. Several experiments have been made tо determine physical and mechanical properties, such as test for compressive and tensile strengths, for impact loading strength, durability test (water absorption) and deep penetration tests. Moreover, the microstructure results for the new type of concrete have been studied by means of scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDXS). The results show that when 70 kg of gelatin powder is added to 1 m3 of concrete, the concrete’s compressive strength and tensile strength are improved more than 22%; during impact loading the first and ultimate cracks are 11 and 129 by numbers, and the first and ultimate cracks’ strength is more than 223 and 2346 J respectively. The durability of sample from concrete with additional gelatin has been improved. SEM results illustrate that the weakness of almond shell concrete is related to cracks and voids between the cement matrix and almond shell. The voids of gelatin concrete are higher than that of conventional concrete. The conventional concrete has smooth crystals, and gelatin concrete has sharp and cubic crystals. EDXS results show that chemical content of these two types of concrete is different: conventional concrete contains silicon, while EDXS results show that chemical content of these two types of concrete is different: conventional concrete contains silicon, while gelatin concrete contains calcium and also C-S-H gel is generated in it

A Novel Minimally Invasive technique for dilatation of hepaticojejunostomy stricture: A case report

Abstract Using a nephroscope in a laparoscopic operation to relieve the hepaticojejunostomy stricture (HJS) by transjejunal dilatation is a minimally invasive and applicable method. It can be used as the first step for such patients

Влияние порошка желатина, миндальной скорлупы и вторичных заполнителей на химические и механические свойства обычного бетона

The objective of the research is to study the effect of different additives on the conventional concrete. In this term, three types of materials have been added to the concrete: gelatin powder as the binder, recycled aggregates, and almond shell as the fine and coarse aggregates. Several experiments have been made tо determine physical and mechanical properties, such as test for compressive and tensile strengths, for impact loading strength, durability test (water absorption) and deep penetration tests. Moreover, the microstructure results for the new type of concrete have been studied by means of scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDXS). The results show that when 70 kg of gelatin powder is added to 1 m3 of concrete, the concrete’s compressive strength and tensile strength are improved more than 22%; during impact loading the first and ultimate cracks are 11 and 129 by numbers, and the first and ultimate cracks’ strength is more than 223 and 2346 J respectively. The durability of sample from concrete with additional gelatin has been improved. SEM results illustrate that the weakness of almond shell concrete is related to cracks and voids between the cement matrix and almond shell. The voids of gelatin concrete are higher than that of conventional concrete. The conventional concrete has smooth crystals, and gelatin concrete has sharp and cubic crystals. EDXS results show that chemical content of these two types of concrete is different: conventional concrete contains silicon, while EDXS results show that chemical content of these two types of concrete is different: conventional concrete contains silicon, while gelatin concrete contains calcium and also C-S-H gel is generated in it.Цель исследования - определить влияние различных добавок на свойства обычного бетона. В бетонную смесь внесены три вида добавок: желатиновый порошок в качестве связующего, вторичные заполнители и миндальная скорлупа в качестве мелкого и крупного заполнителей. Проведено исследование по определению физико-механических свойств бетона с указанными добавками: прочности на сжатие и растяжение, испытания на ударную нагрузку, на долговечность (водопоглощение) и на глубину проникновения влаги в бетон. Микроструктура бетона изучена с помощью сканирующей электронной микроскопии (SEM) и энергодисперсионной рентгеновской спектроскопии (EDXS). Установлено, что при добавлении 70 кг желатинового порошка на 1 м3 бетона его прочность на сжатие и растяжение увеличилась более чем на 22 %; под действием ударной нагрузки начальное и предельное количество трещин составляет 11 и 129, а начальная и предельная прочность трещинообразования - более 223 и 2346 Дж соответственно. Кроме того, показатели долговечности лучше у бетона с добавлением желатина. Результаты, полученные при помощи SEM, демонстрируют, что пониженная прочность бетона с добавлением миндальной скорлупы связана с трещинами и пустотами между цементной матрицей и миндальной скорлупой. Пустоты в бетоне с желатином выше, чем в обычном бетоне. Структура обычного бетона имеет вид гладких кристаллов, а бетона с желатином - острые и кубические кристаллы. Результаты, полученные с помощью EDXS, показали различие в химическом составе: обычный бетон содержит кремний, тогда как бетон с добавкой желатина в вышеуказанных пропорциях содержит кальций и в нем образуется гель C-S-H