OS11-1-1 Estimation of Compressive Strength of Concrete Structures by the Impact Elastic Wave Method

Recycling of waste plastics is an essential phase towards cleaner production and circular economy. Plastics in different forms, which are non-biodegradable polymers, have become an indispensable ingredient of human life. The rapid growth of the world population has led to increased demand for commodity plastics such as food packaging. Therefore, to avert environment pollution with plastic wastes, sufficient management to recycle this waste is vital. In this study, experimental investigations and statistical analysis were conducted to assess the feasibility of polypropylene type of waste plastic food tray (WPFT) as fibrous materials on the mechanical and impact resistance of concrete composites. The WPFT fibres with a length of 20 mm were used at dosages of 0–1% in two groups of concrete with 100% ordinary Portland cement (OPC) and 30% palm oil fuel ash (POFA) as partial cement replacement. The results revealed that WPFT fibres had an adverse effect on the workability and compressive strength of concrete mixes. Despite a slight reduction in compressive strength of concrete mixtures, tensile and flexural strengths significantly enhanced up to 25% with the addition of WPFT fibres. The impact resistance and energy absorption values of concrete specimens reinforced with 1% WPFT fibres were found to be about 7.5 times higher than those of plain concrete mix. The utilisation of waste plastic food trays in the production of concrete makes it low-cost and aids in decreasing waste discarding harms. The development of new construction materials using WPFT is significant to the environment and construction industry.

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The Effect of Different Curing Conditions on Compressive Strength of Concrete

Pakistan Journal of Scientific & Industrial Research Series A: Physical Sciences ◽

10.52763/pjsir.phys.sci.60.3.2017.147.153 ◽

2017 ◽

Vol 60 (3) ◽

pp. 147-153

Author(s):

Muhammad Arslan ◽

Muhammad Asif Saleem ◽

Maria Yaqub ◽

Muhammad Saleem Khan

Keyword(s):

Compressive Strength ◽

Research Work ◽

Concrete Structures ◽

Strength Test ◽

The Other ◽

Cylindrical Shape ◽

Curing Conditions ◽

Compressive Strength Test ◽

Different Types ◽

Compressive Strength Of Concrete

The focus of this research work was to analyse the effect of different types of curing oncompressive strength of concrete structures. For this purpose, 54 test specimens of cylindrical shape wereprepared. These specimens were cured with different methods and were tested on different age days toanalyse the effect of curing on compressive strength. Test specimens cured with conventional water curingmethod gives the highest results as compared to the other adopted methods.

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The Assessment of Strength of Cementitious Materials Impregnated Using Hydrophobic Agents Based on Near-Surface Hardness Measurements

Materials ◽

10.3390/ma14164583 ◽

2021 ◽

Vol 14 (16) ◽

pp. 4583

Author(s):

Martyna Nieświec ◽

Łukasz Sadowski

Keyword(s):

Compressive Strength ◽

Cement Paste ◽

Concrete Structures ◽

Surface Hardness ◽

Cementitious Materials ◽

Schmidt Hammer ◽

Near Surface ◽

Cement Ratio ◽

Water Cement Ratio ◽

The Impact

Recently, the surfaces of concrete structures are impregnated to protect them against the environment in order to increase their durability. It is still not known how the use of these agents affects the near-surface hardness of concrete. This is especially important for experts who use the near-surface hardness of concrete for estimating its compressive strength. The impregnation agents are colorless and, thus, without knowledge of their use, mistakes can be made when testing the surface hardness of concrete. This paper presents the results of investigations concerning the impact of impregnation on the subsurface hardness concrete measured using a Schmidt hammer. For this research, samples of cement paste with a water–cement ratio of 0.4 and 0.5 were used. The samples were impregnated with one, two, and three layers of two different agents. The first agent has been made based on silanes and siloxanes and the second agent has been made based on based on polymers. The obtained research results allow for the conclusion that impregnation affects the near-surface hardness of concrete. This research highlights the fact that a lack of knowledge about the applied impregnation of concrete when testing its near-surface hardness, which is then translated into its compressive strength, can lead to serious mistakes.

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Impact of impurities of local construction materials on the bearing capacity of the concrete used in structures in Burundi

Vestnik MGSU ◽

10.22227/1997-0935.2021.10.1357-1362 ◽

2021 ◽

pp. 1357-1362

Author(s):

Emmanuel Mikerego ◽

Nestor Niyonzima ◽

Jean Claude Ntirampeba

Keyword(s):

Compressive Strength ◽

Reinforced Concrete ◽

Concrete Structures ◽

Construction Materials ◽

Reinforced Concrete Structures ◽

Ordinary Concrete ◽

Average Decrease ◽

Local Construction ◽

The Impact ◽

Mixing Water

Introduction. The article is about an assessment of the impact of impurities contained in the local construction materials on the mechanical characteristics of the concrete used in reinforced concrete structures in Burundi. Materials and methods. The methodology of the study consisted in varying the quantity of impurities for the manufacturing of the concrete experimental cubic samples. The grain sizes of the studied ordinary concrete were in the favourable zones according to the recommended granulometry for standard concretes. Simulation of impurities was made by adding in the mixing water solid particles taken from a local rock called “red earth”. The particles were composed by (24 %) of clays, (38 %) of silts and (38 %) of sands. As for the used cement in this study, it was the type CEM I (32.5). The quantities of impurities were expressed in grams per litre of mixing water (g/l) and were varying from (0 g/l) to (100 g/l) with a step of (20 g/l). The prepared experimental concrete samples were stored in the laboratory of materials at the University of Burundi and were subjected to compression testing under hydraulic press after 28 days. Results. The impact of impurities consisting of (24 %) of clays, (38 %) of silts and (38 %) of sands is identified. Each increase of (20 g) of impurities in a litre of mixing water induces an average decrease of (4 %) on the compressive strength and the Young’s modulus for an ordinary concrete. Conclusions. The impact of impurities contained in the local construction materials used in the manufacturing of the concrete for reinforced concrete structures in Burundi is studied. Each increase of (20 g) of impurities in a litre of mixing water induces an average decrease of (4 %) on the compressive strength and the Young’s modulus of an ordinary concrete. For Burundi, a curve for the approximation of the bearing capacity of the concrete used in reinforced concrete structures according to the quantity of impurities contained in the local construction materials was established. Hence, it is advisable to start by the specification of the quantity of impurities contained in the construction materials before making the concrete for reinforced concrete structures in order to predict the mechanical performances of the concrete used in reinforced concrete structures.

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Recycling of Stone Cutting Waste In the Construction Sector: A Review

The Journal of Solid Waste Technology and Management ◽

10.5276/jswtm/2021.56 ◽

2021 ◽

Vol 47 (1) ◽

pp. 56-60

Author(s):

Kamel Al-Zboon ◽

Talal Masoud

Keyword(s):

Compressive Strength ◽

Flexural Strength ◽

Construction Sector ◽

Replacement Ratio ◽

Splitting Strength ◽

Substitution Ratio ◽

Stone Cutting ◽

Compressive Strength Of Concrete ◽

The Cost ◽

The Impact

Huge amounts of stone cutting waste are generated annually posing a heavy environmental load on nature and resulting in economic challenge to the plants' owners. The conducted researches in this field showed that stone, marble and granite waste could be reused in many applications. This paper aims to investigate the possible application of stone cutting waste in the construction sector. Review process includes investigation of the conducted researches, outcomes of the performed projects, and the impact of this waste on the characteristics of concrete compressive strength, flexural strength, splitting strength, concrete workability, bricks strength, terrazzo tile strength and soil properties. The results revealed that at suitable substitution ratio, this waste can increase the compressive strength of concrete up to 21%, the flexural strength by 33% and splitting strength by 4.3%. In contrast, the compressive strength of bricks decreased by up to 67% at replacement ratio of 100%, and the transverse strength of tiles decreased up to 18% at replacement ratio of 50%. Replacement of soil with stone cutting waste resulted in an improvement in the characteristics of cohesive and sandy soil. Concrete workability decreased significantly with replacement of normal aggregate with stone cutting waste. Such results buttressed the feasibility of reusing this material in the construction sector, which reduces the cost of storage and disposal, and creates a nonconventional income.

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A review: sustainable compressive strength properties of concrete mix with replacement by marble powder

Journal of Achievements of Materials and Manufacturing Engineering ◽

10.5604/01.3001.0014.0813 ◽

2020 ◽

Vol 1 (98) ◽

pp. 11-23

Author(s):

N. Sharma ◽

M. Singh Thakur ◽

P.L. Goel ◽

P. Sihag

Keyword(s):

Compressive Strength ◽

Design Methodology ◽

Strength Properties ◽

Concrete Mixture ◽

Fine Aggregates ◽

Concrete Mix ◽

Marble Powder ◽

Compressive Strength Of Concrete ◽

The Impact

Purpose: Over the years, various experiments have been performed to investigate the impact of marble powder within the concrete mixture. In the present study, a review has been done to check the persistence of marble dirt as the substitute for concrete constituents. Design/methodology/approach: Furthermore, the impact of marble powder as a replacement of cement and aggregates were reviewed. By reviewing previous studies, the result indicates that the use of waste marble powder in cement and aggregate was adequate to a certain range. Findings: By replacing cement with marble powder in a range between 5% to 10% by weight, it increases the compressive strength of concrete mix by 11.30% to 24.56%, compared to the nominal mix. According to the study, any further increase in the amount of marble powder in place of cement i.e, 12.5% to 20% replacement by weight, results in the reduction of compressive strength of concrete mix by 7.5% to 26.01%. Replacement of aggregates from 5% to 75% with marble powder increases the compressive strength of about 3.22% to 23.91% as compared to the nominal mix. Research limitations/implications: It was also concluded from the current study that, to obtain higher compressive strength, it is advantageous to replace fine aggregates with marble powder than the replacement of cement with the marble powder.

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