scholarly journals Developing Sustainable Concrete Compaction using a Proposed Multi-vibration Technique

2020 ◽  
Vol 13 (1) ◽  
pp. 45-53
Author(s):  
Sajid Kamil Zemam
Keyword(s):  
Compressive Strength ◽  
Vibration Mode ◽  
Sustainable Construction ◽  
Experimental Program ◽  
Specific Method ◽  
Concrete Compressive Strength ◽  
Time Duration ◽  
Construction Technique ◽  
Vibration Technique ◽  
Concrete Production

This study seeks to develop a sustainable construction technique based on the introduction of a specific method for improving concrete compressive strength through a proposed multi-vibration compaction method. An experimental program is performed to evaluate the effect of the proposed compaction technique on fresh silica fume concrete undergoing the initial setting. Multi-vibration intends to minimize concrete production cost because it upgrades the compressive strength of the same materials with better utilization of the vibration energy required for compaction. The collected experimental data presented assign relationships among vibration duration, vibration cycles or phases, and compressive strength upgrading of single vibrated, revibrated, and multi-vibrated specimens for analysis and discussion. This study shows that multi-vibration phases, rather than single vibration or revibration techniques, are powerful techniques for improving concrete compressive strength. The results indicated that the existence of an optimum multi-vibration mode was dominated by phase number and vibration duration and confirm the reliability vibration overall time duration recommended by ACI 309 which relates to a single vibration time limit to be considered in the case of multi vibration technique. Multi-vibration Mode 8 (subjected to three vibration phases 10, 20, and 30 sec ) has the best effect for the considered mixtures among the specific vibration modes. The maximum improvement ratio is 1.25, which is associated with the plastic mixture.   

scholarly journals Assessment of Concrete Compressive Strength by Ultrasonic Non-Destructive Test

2021 ◽  
Vol 318 ◽  
pp. 03004
Author(s):  
AbdulMuttalib I. Said ◽  
Baqer Abdul Hussein Ali
Keyword(s):  
Compressive Strength ◽  
Salt Content ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Experimental Program ◽  
Concrete Compressive Strength ◽  
Statistical Program ◽  
Non Destructive ◽  
Accurate Relation

This paper has carried out an experimental program to establish a relatively accurate relation between the ultrasonic pulse velocity (UPV) and the concrete compressive strength. The program involved testing concrete cubes of (100) mm and prisms of (100×100×300) cast with specified test variables. The samples are tested by using ultrasonic test equipment with two methods, direct ultrasonic pulse (DUPV) and surface (indirect) ultrasonic pulse (SUPV) for each sample. The obtained results were used as input data in the statistical program (SPSS) to predict the best equation representing the relation between the compressive strength and the ultrasonic pulse velocity. In this research 383 specimens were tested, and an exponential equation is proposed for this purpose. The statistical program has been used to prove which type of UPV is more suitable, the (SUPV) test or the (DUPV) test, to represent the relation between the ultrasonic pulse velocity and the concrete compressive strength. In this paper, the effect of salt content on the connection between the ultrasonic pulse velocity and the concrete compressive strength has also been studied.

The Application of Waste Marble as Coarse Aggregate in Concrete Production

2018 ◽  
Vol 15 (1) ◽  
pp. 75
Author(s):  
Kok Yung Chang ◽  
Wai Hoe Kwan ◽  
Hui Bun Kua
Keyword(s):  
Compressive Strength ◽  
Coarse Aggregate ◽  
Maximum Size ◽  
Pulse Velocity ◽  
Chloride Penetration ◽  
Sustainable Construction ◽  
Replacement Level ◽  
Optimum Result ◽  
Concrete Production ◽  
Production Industry

The massive growth of construction industry especially in the developing countries results in extensive quarrying activities which ultimately would lead to the depletion of natural resources. Apart from extensive extraction of the natural granite from the earth for concrete production, marble production industry is also majorly contributing to the quarrying activities. In addition, high volume of waste is generated by the marble production industry as 70% of marble is wasted during the production such as quarrying, cutting, processing and others which is environmental unfriendly. In a way to achieve sustainable construction, the present study is to utilise the waste marble in replacing the coarse aggregate in concrete production. The engineering performance including workability, compressive strength, ultrasonic pulse velocity (UPV) and chloride penetration were analysed. The raw waste marble obtained from the industry were crushed and sieved into maximum size 20 mm and used to replace the coarse aggregate at the level of 20%, 40%, 60%, 80% and 100% respectively. Results show that 60% of the replacement level has yield to optimum result by achieving the highest compressive strength and UPV at approximate 5% higher than the control. Meanwhile, the effect on chloride penetration resistance is more significant, i.e. approximate 19% better than the control. However, increasing the replacement level of waste marble has no significant effect on workability, although an increasing trend was observed.

scholarly journals Concrete Compressive Strength under Changing Environmental Conditions during Placement Processes

Materials ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 4577 ◽  
Author(s):  
Andrzej Ambroziak ◽  
Patryk Ziolkowski
Keyword(s):  
Compressive Strength ◽  
Technological Process ◽  
Daily Temperature ◽  
Hardened Concrete ◽  
Concrete Compressive Strength ◽  
Concrete Mix Design ◽  
Temperature And Precipitation ◽  
Concrete Production ◽  
Concrete Mix ◽  
Limiting Behaviour

The technological process of concrete production consists of several parts, including concrete mix design, concrete mix production, transportation of fresh concrete mix to a construction site, placement in concrete framework, and curing. Proper execution of these steps provides good quality concrete. Some factors can disturb the technological process, mainly temperature and excessive precipitation. Changing daily temperature and rainfall during fabrication, transportation, and placement can shape not only the properties of the concrete mix but also the compressive strength of hardened concrete. In this paper, we tried to answer the question of how temperature and precipitation affect concrete production. The scope of this study was to determine the change of compressive strength of the hardened concrete in a specific period for selected concrete mix recipes, taking into account changing daily temperature and precipitation magnitude. The investigated concrete mixes concrete compressive strength beyond that of the concrete grade, termed “concrete superstrength”. This concrete post limiting behaviour of concrete is also discussed.

scholarly journals Analysis and validation of correlation curves between sclerometry and compression tests for the evaluation of compressive strength of concretes

2018 ◽  
Vol 11 (4) ◽  
pp. 779-809
Author(s):  
T. M. OLIVEIRA ◽  
M. C. R. FARAGE ◽  
L. GOLIATT ◽  
T. C. BITTENCOURT
Keyword(s):  
Compressive Strength ◽  
Experimental Program ◽  
Construction Site ◽  
Structural Elements ◽  
Compression Tests ◽  
Concrete Compressive Strength ◽  
Equipment Manufacturer ◽  
Cylindrical Samples ◽  
Compressive Tests

Abstract The present work consists in obtaining correlation curves between compressive tests and sclerometry tests from an extensive experimental program comprising 630 concrete cylindrical samples cast in laboratory, employing materials and methods available in Brazil. The concretes, with compressive strengths ranging from 20~MPa to 50~MPa, were submitted to sclerometry tests and mechanical compressive tests. The results were used to obtain correlation curves. which were adopted in measurements of structural elements molded in a construction site, indicating that the curves provided by the equipment manufacturer are not suitable for the material in study. This is the first stage of a broader study aiming to contribute to the improvement of the Brazilian code regulating the application of the sclerometry to obtain concrete compressive strength.

scholarly journals Perceptions on construction-related factors that affect concrete quality, costs and production

2018 ◽  
Vol 10 (1) ◽  
Author(s):  
Jorge Luis Santamaria ◽  
Vanessa Valentin
Keyword(s):  
Compressive Strength ◽  
Mixing Time ◽  
Affecting Factors ◽  
Concrete Compressive Strength ◽  
Production Rates ◽  
Related Factors ◽  
Quality Costs ◽  
Importance Index ◽  
Concrete Production ◽  
Compaction Method

Structured and unstructured factors affect concrete product. Structured factors are related to concrete production and unstructured factors are related to the construction process. This study focuses on examining the perceived importance of unstructured factors (i.e., construction-related factors) on concrete compressive strength, concrete costs and production rates on the jobsite and understanding the influence of construction experts’ characteristics, such as profession, on their perceptions. A comprehensive literature review was performed to identify unstructured factors. A survey was then designed and deployed to 297 experts from the construction industry and academia to examine the importance of the identified factors through the relative importance index (RII) method and to further identify additional unstructured factors. Likert aggregation and tests for equality of odds were used to compare and analyze responses of two groups of participants, namely architects and engineers. Curing humidity, crew experience and compaction method are the top three factors perceived to affect concrete compressive strength, whereas crew experience, mixing time and compaction method are the factors perceived to affect concrete costs and production rates the most. Crew experience, compaction method and mixing time dominate the global ranking of perceived affecting factors for concrete compressive strength, costs and production rates. Architects were found to be more likely to perceive high or very high impacts of these factors on concrete. The present study increases our understanding of construction-related factors to facilitate project management and preserve concrete characteristics.

scholarly journals APPLICATION OF GRAPHENE OXIDE IN CEMENTITIOUS COMPOSITES FOR CEMENT CONTENT REDUCTION

2018 ◽  
Vol 1 (1) ◽  
pp. 4-9
Author(s):  
Renan Pícolo Salvador ◽  
Roberto Munhoz Bueno ◽  
Dimas Alan Strauss Rambo ◽  
Sandro Martini
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Graphene Oxide ◽  
Cement Content ◽  
Isothermal Calorimetry ◽  
Construction Materials ◽  
Phase Evolution ◽  
Sustainable Construction ◽  
Experimental Program ◽  
Cementitious Composites

Cement production is responsible for 5% of CO2 emissions worldwide. The concern about the pollution derived from the construction industry has brought attention to the need of developing more sustainable construction materials and processes. Admixtures based on nanometric graphene oxide have the potential to enhance mechanical properties and durability of cementitious composites. In this context, an experimental program was conducted to evaluate how the addition of graphene oxide may be used to reduce cement content in concretes, maintaining the same mechanical properties of conventional concretes (control matrices, with no graphene oxide additions). Kinetics of hydration of cement pastes was evaluated by isothermal calorimetry, phase evolution during hydration was determined by X-ray diffraction coupled with quantitative Rietveld analysis and mechanical properties were evaluated by compressive strength. Results indicate that graphene oxide additions provide a faster hydration rate until 24 h and generate a larger amount of C-S-H gel, increasing mechanical strength of the matrix. By the addition of graphene oxide dispersion (0.4% of solid content) at 0.02% by cement weight, cement content reductions of up to 15% may be achieved, maintaining the same compressive strength as the control matrices. From this research, a reduction in cement content to obtain more sustainable construction materials and processes may be achieved.

scholarly journals Physical Properties and Microstructure of Concrete with Waste Basalt Powder Addition

Materials ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 3503 ◽  
Author(s):  
Magdalena Dobiszewska ◽  
Ahmet Beycioğlu
Keyword(s):  
Compressive Strength ◽  
Water Transport ◽  
Experimental Program ◽  
Natural Sand ◽  
Concrete Production ◽  
Lower Porosity ◽  
Powder Addition ◽  
Natural Aggregates ◽  
Main Components ◽  
Water Transport Properties

The natural aggregates are one of the main components in the production of concrete. Although deposits of natural aggregates lie on the earth’s surface or at low depths and belong to common deposits, the shortage of aggregate, especially natural sand, is presently observed in many countries. In such a situation, one is looking for other materials that can be used as a substitute for natural aggregates in mortars and concrete production. This paper presents the results of an experimental investigation carried out to evaluate the potential usage of waste basalt powder in concrete production. For this purpose, the waste basalt powder, which is a by-product of the production of mineral–asphalt mixtures, was substituted with 10%, 20%, and 30% sand replacement. In the experimental program, the workability, compressive strength, water transport properties, and microstructural performances were evaluated. The results showed that the production of concretes that feature a strong internal structure with decreased water transport behavior is possible with waste basalt usage. Furthermore, when waste basalt powder is used as a partial sand replacement, the compressive strength of concretes can be increased up to 25%. According to the microstructural analyses, the presence of basalt powder in concrete mixes is beneficial for cement hydration products, and basalt powder substituted concretes have lower porosity within the interfacial transition zone.

The Application of Waste Marble as Coarse Aggregate in Concrete Production

2018 ◽  
Vol 15 (1) ◽  
pp. 75
Author(s):  
KOK YUNG CHANG ◽  
WAI HOE KWAN ◽  
HUI BUN KUA
Keyword(s):  
Compressive Strength ◽  
Coarse Aggregate ◽  
Maximum Size ◽  
Pulse Velocity ◽  
Chloride Penetration ◽  
Sustainable Construction ◽  
Replacement Level ◽  
Optimum Result ◽  
Concrete Production ◽  
Production Industry

The massive growth of construction industry especially in the developing countries results in extensive quarrying activities which ultimately would lead to the depletion of natural resources. Apart from extensive extraction of the natural granite from the earth for concrete production, marble production industry is also majorly contributing to the quarrying activities. In addition, high volume of waste is generated by the marble production industry as 70% of marble is wasted during the production such as quarrying, cutting, processing and others which is environmental unfriendly. In a way to achieve sustainable construction, the present study is to utilise the waste marble in replacing the coarse aggregate in concrete production. The engineering performance including workability, compressive strength, ultrasonic pulse velocity (UPV) and chloride penetration were analysed. The raw waste marble obtained from the industry were crushed and sieved into maximum size 20 mm and used to replace the coarse aggregate at the level of 20%, 40%, 60%, 80% and 100% respectively. Results show that 60% of the replacement level has yield to optimum result by achieving the highest compressive strength and UPV at approximate 5% higher than the control. Meanwhile, the effect on chloride penetration resistance is more significant, i.e. approximate 19% better than the control. However, increasing the replacement level of waste marble has no significant effect on workability, although an increasing trend was observed.

scholarly journals The Use of Calcined Waste Glass Powder As a Pozzolanic Material

2019 ◽  
Vol 4 (12) ◽  
pp. 53-56
Author(s):  
John Ayibatunimibofa TrustGod ◽  
Akosubo Iwekumo Stevyn ◽  
Ann Diri Manfred
Keyword(s):  
Compressive Strength ◽  
Glass Powder ◽  
Fine Powder ◽  
Well Being ◽  
Waste Glass ◽  
Concrete Compressive Strength ◽  
Pozzolanic Material ◽  
Waste Glass Powder ◽  
Concrete Production ◽  
Different Temperatures

The amounts of waste glass in the Bayelsa State metropolis have been growing noticeably without being reutilized increasing the danger to public well-being because of the shortage of land area. This rising challenge of waste glass in the Bayelsa State metropolis can be improved if new dumping possibilities other than landfill can be discovered. This study is geared toward the better use of waste glass material as admixture in concrete as a means to improve the concrete compressive strength. To achieve research objectives, the broken waste glasses were obtained from aluminum fabrication workshop in Amassoma. Bayelsa state Nigeria, the glasses were then milled to a fine powder smaller than 0.075mm and burnt at a controlled temperature of 200, 400, and 6000C respectively. A total of 156 concrete cubes of 150mm x 150mm x 150mm were produced employing different contents of calcined or burnt waste glass powder as admixture. The quantity of calcined waste glass powder used as admixture was varied from 0-20% at step of 5% for three different temperatures, 2000C, 4000C and 6000C. The samples were cured for 7, 14, 21 and 28days and tested in the laboratory for compressive strength. Results obtained from the study showed that the best addition dosage of calcined waste glass powder at 2000C, 4000C and 6000C are 20%, 5% and 5%. A 20% addition of Calcined waste glass powder at 2000C exhibited about 23% increase in compressive strength than the control. Base on the findings, it is recommended that the use of calcined waste glass powder as pozzolanic material should be embraced for production of concrete and can be utilized in concrete production as admixture with 5% - 20% for 2000C 4000Cand 4000C respectively.

scholarly journals Moment Redistribution in Continuous RC Beams Top Strengthened with Steel and CFRP Plates

2020 ◽  
Vol 8 (6) ◽  
pp. 3472-3480
Keyword(s):  
Compressive Strength ◽  
Reinforcement Ratio ◽  
Steel Plates ◽  
Fiber Reinforced Polymer ◽  
Experimental Program ◽  
Rc Beams ◽  
Fiber Reinforced ◽  
Concrete Compressive Strength ◽  
Moment Redistribution ◽  
Reinforced Polymer

It is common practice to retrofit continuous reinforced concrete (RC) beams by fiber reinforced polymer (FRP) or steel plates. This can cause a significant amount of moment redistribution (MR) which results in an efficient and economic design when taken into consideration. There is lack in research regarding MR in continuous RC beams when strengthening plates are applied only at the top side at the hogging regions. The main purpose of this paper is to assess MR in continuous RC beams top strengthened with steel and/or carbon fiber reinforced polymer (CFRP) plates. In this respect, a nonlinear finite element model was developed using ABAQUS 6.14 and validated using experimental research program. The model was found capable of stimulating the behavior of such beams and hence assessing the percentage of MR which can be achieved using steel and CFRP strengthening. A parametric study is conducted to investigate the effect of various parameters, different from those investigated in the experimental program, on the MR in continuous RC beams. Parameters related to the concrete compressive strength, reinforcement ratio, beam thickness and thickness of strengthening plates were considered in this study. The results showed that significant amounts of MR can be achieved using either steel or CFRP plates and that MR is enhanced with the change in concrete compressive strength. Moreover, it was found out that the change in steel bars reinforcement ratio or in thickness of the strengthening plates has different effect on the beams strengthened with steel plates than those strengthened with CFRP plates.

Sign in / Sign up

Export Citation Format

Share Document