Analysis of Regression for Strength Index of Concrete Performed Brick Masonry

2013 ◽  
Vol 639-640 ◽  
pp. 803-806
Author(s):  
Qi Fang Wang
Keyword(s):  
Compressive Strength ◽  
Bending Strength ◽  
Brick Masonry ◽  
Adjustment Coefficient ◽  
Masonry Structures ◽  
Strength Index ◽  
Strength Tests ◽  
Compressive Strength Of Concrete ◽  
Basic Strength ◽  
Regressive Analysis

Based on the data of the strength tests of concrete performed brick masonry，the basic strength formulas of concrete performed brick masonry are obtained. Through regressive analysis, it will be coherent to the compressive strength of concrete performed brick masonry to introduce the adjustment coefficient of mortar contrast to the Code for Design of Masonry Structures of China. The shear strength, bending strength along straight joint and bending strength along straight joint are uniform with the Code for Design of Masonry Structures of China.

Effects of 0-30% Wood Ashes as a Substitute of Cement on the Strength of Concretes

2022 ◽  
Author(s):  
Theodore Gautier Bikoko ◽  
Jean Claude Tchamba ◽  
Valentine Yato Katte ◽  
Divine Kum Deh
Keyword(s):  
Compressive Strength ◽  
Portland Cement ◽  
Greenhouse Gases ◽  
Negative Influence ◽  
Wood Ash ◽  
The Other ◽  
Other Hand ◽  
Strength Tests ◽  
Compressive Strength Of Concrete ◽  
Curing Age

To fight against the high cost and the increasing scarcity of cement and at the same time to reduce the CO2 greenhouse gases emission associated with the production of Portland cement, two types of wood ashes as a substitute of cement in the production of concretes were investigated. In this paper, we substituted cement by two types of species of wood ashes namely, avocado and eucalyptus ashes following the proportions ranging from 0% to 30 % on one hand, and on the other hand, we added these two types of species of wood ashes namely, avocado and eucalyptus ashes following the proportions ranging from 0% to 10 % by weight of cement in the concrete samples. After 7, 14 and 28 days of curing, compressive strength tests were conducted on these concrete samples. The findings revealed that using wood ashes as additives/admixtures or as a substitute of cement in the production/manufacturing of concrete decreased the compressive strength of concrete. Hence, it can be said that wood ash has a negative influence on the strength of concrete. At three percent (3%) and ten percent (10%) of addition, the wood ash from eucalyptus specie offers better resistance compared to the wood ash from avocado specie, whereas at five percent (5%) of addition, the wood ash from avocado specie offers better resistance compared to the wood ash from eucalyptus specie. At thirty percent (30%) of substitution, the wood ash from eucalyptus specie offers better resistance compared to the wood ash from avocado specie. The compressive strengths increase with the increase of curing age.

scholarly journals Compressive Strength Studies on Recycled Binder Concrete

2021 ◽  
Vol 11 (4) ◽  
pp. 7332-7335
Author(s):  
D. D. Nguyen ◽  
V. T. Phan
Keyword(s):  
Compressive Strength ◽  
Strength Development ◽  
Recycled Materials ◽  
Strength Tests ◽  
Compressive Strength Of Concrete ◽  
Recycled Waste ◽  
Curing Cement

Recycled materials are gradually utilized in concrete. This paper examines the use of recycled binder in concrete. The compressive strength tests on concrete incorporating recycled binder instead of cement were carried out after 7, 14, and 28 days of curing. Cement was replaced by the recycled binder in ratios of 10%, 20%, and 30% by weight. The results show that the compressive strength of concrete is strongly affected by the percentage of the recycled binder. It has been found that the compressive strength decreases linearly with the increasing content of recycled binder. The recycled binder does not affect the strength development of concrete. In order to apply recycled waste to concrete as a binder, it is necessary to perform supplement research with appropriate additives to compensate for the loss of the compressive strength.

Tensile Strength of Concrete at Different Strain Rates

1985 ◽  
Vol 64 ◽  
Author(s):  
Parviz Soroushian ◽  
Ki-Bong Choi ◽  
Gung Fu
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Moisture Content ◽  
Strain Rate ◽  
Rate Sensitivity ◽  
Strain Rates ◽  
Direct Tension ◽  
Dynamic Tensile Strength ◽  
Strength Tests ◽  
Compressive Strength Of Concrete

ABSTRACTResults of dynamic tensile strength tests of concrete, produced by the authors and other investigators, were used to study the effects of strain rate on the tensile strength of concrete. The influence of moisture content and compressive strength of concrete, and type of test (splitting tension, flexure, or direct tension) on the strain rate-sensitivity of the tensile strength were evaluated. An empirically developed expression is presented for the dynamic-to-static ratio of concrete tensile strength in terms of the rate of straining.

Optimization of the Mixing Ratio of Two Different Clays Used for Ceramic Roof Tiles

2010 ◽  
Vol 659 ◽  
pp. 477-482
Author(s):  
Róbert Géber ◽  
István Kocserha ◽  
Viktor Orosz ◽  
Andrea Simon ◽  
Csilla Paróczai
Keyword(s):  
Compressive Strength ◽  
Bending Strength ◽  
Mechanical Test ◽  
Mixing Ratio ◽  
Industrial Partner ◽  
Laboratory Vacuum ◽  
Strength Tests ◽  
Brick And Tile ◽  
Mineral Mixtures ◽  
In Virtue Of

Brick- and tile manufacturing is one of the most rapidly developing industries. Professionals are constantly seeking modern technological solutions with which much better and longer lifetime of ceramic roof tiles can be reached. The aim of this R&D work was to optimize the mixing ratio of two different clay minerals of the industrial partner. The Authors have tried to develop a mixture by increasing the mixing ratio of the clay „Jamina”, which reaches or exceeds the mechanical strength and frost-resistance of the ceramic roof tiles which were made according to the present recipe used by the industrial partner. After XRD tests in virtue of preliminary mixture design, the Authors have made clay mineral mixtures that were milled and homogenized in an edge mill for an appropriate grain size. After mixing and homogenizing, samples with different length were made for further investigations with the use of a laboratory vacuum extrusion system. Shrinkage after drying and firing, apparent porosity and water absorption were measured on these samples. Mechanical test were also executed, as well as bending strength tests and compressive strength tests. On the basis of the results of the executed tests, it can be seen that the Authors were successfully developed clay mixtures, with which ceramic roof tiles can be produced with properties that are more favourable than the present mixture used by the industrial partner. The increase of the ratio of ‘Csaba I.’ clay increases the bending and compressive strength of the fired ceramic roof tiles. So the reduction of the amount of clay „Jamina” affects the mechanical properties of the ceramic roof tiles favourably.

scholarly journals Mechanical Performance of Concrete Exposed to Sewage—The Influence of Time and pH

Minerals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 544
Author(s):  
Justyna Czajkowska ◽  
Maciej Malarski ◽  
Joanna Witkowska-Dobrev ◽  
Marek Dohojda ◽  
Piotr Nowak
Keyword(s):  
Compressive Strength ◽  
Mechanical Performance ◽  
Negative Influence ◽  
Concrete Compressive Strength ◽  
Active Sludge ◽  
Strength Tests ◽  
Compressive Strength Of Concrete ◽  
And Performance ◽  
The Relationship ◽  
Microstructure And Performance

Contact of concrete with aggressive factors, technological structures, reduces their durability through microstructural changes. This work presents the results of research on determining the influence of post grit chamber sewage and sewage from the active sludge chamber in three different environments, i.e., acidic, neutral, and alkaline, on the structure and compressive strength of concrete. Compressive strength tests were carried out after 11.5 months of concrete cubes being submerged in the solutions and compared. To complete the studies, the photos of the microstructure were done. This made it possible to accentuate the relationship between the microstructure and performance characteristics of concrete. The time of storing the cubes in both acidic environments (sewage from post grit chamber and active sludge chamber) has a negative influence on their compressive strength. The compressive strength of cubes decreases along with the time. Compressive strength of cubes increases with increasing pH of the environment.

scholarly journals Humidity and specimen preparation procedure: influence on compressive strength of concrete blocks

2021 ◽  
Vol 14 (2) ◽  
Author(s):  
Guilherme Aris Parsekian ◽  
André Luis Christoforo ◽  
Amanda Duarte Escobal Mazzú ◽  
Gláucia Maria Dalfré
Keyword(s):  
Compressive Strength ◽  
Concrete Block ◽  
Block Type ◽  
Specimen Preparation ◽  
Standard Procedures ◽  
Strength Tests ◽  
Concrete Blocks ◽  
Compressive Strength Of Concrete ◽  
Average Block ◽  
Best Fit

abstract: It is extremely important that the quality control of the concrete block used in structural masonry is conducted based on standard procedures that allow reliable estimation of the properties of these components. This work aims to analyze and evaluate the influence of the concrete block moisture on the result of the compression test. Hollow concrete blocks were prepared and subsequently maintained in different environments for various periods of time and under different conditions of temperature and humidity to determine the influence of the type of drying on the relative humidity of the block at the time of testing and consequently on its compressive strength. As a conclusion, it can be stated that, because it is necessary to use water in the process, the grinding rectification of the faces of the blocks led them to have high humidity, above 70%. If tested in this condition, the results of the compressive strength tests will be lower than that of blocks under usual environmental conditions. No differences were found in the average block strength when they were kept dry in the controlled environment of the laboratory during periods of 24 or 48 h. After grinding, it is not necessary to dry the blocks inside an oven at 40ºC before the tests; simply leaving them at a usual room temperature of 23ºC and humidity of 40 ± 5% for 24h is sufficient. The attempt to accelerate drying in an oven at 100ºC is not adequate because this leads to an increase in the compressive strength. From the results, it was possible to determine expressions to correlate the compressive strength as a function of the moisture of the block at the time of the test. The best-fit expressions are distinct for each block type, but the formulations are consistent in indicating a considerable difference in resistance as a function of moisture.

scholarly journals Pemanfaatan Hasil Pembakaran Limbah Cangkang Kelapa Sawit sebagai Bahan Pengganti Pasir pada Pembuatan Beton Normal

2017 ◽  
Vol 6 (1) ◽  
pp. 30-40
Author(s):  
Fauzi Rahman ◽  
Fathurrahman Fathurrahman
Keyword(s):  
Compressive Strength ◽  
Oil Palm ◽  
Chemical Elements ◽  
Normal Mixture ◽  
Normal Concrete ◽  
Strength Tests ◽  
Compressive Strength Of Concrete ◽  
Concrete Testing ◽  
Fresh Fruit Bunches

In 2015 the total area of oil palm plantations in Kalimantan reached 3.47 million Ha with a production of 8.12 million tons per year. Solid waste is in the form of fresh fruit bunches and palm shells. The result of combustion of oil palm shell waste in the form of boiler crust ash is a waste that has chemical elements SiO2, Al2O3, and CaO, with the content of these compounds can affect the strength of the concrete and can increase its strength. In this study, the quality of the concrete mix planned at 28 days is 23 MPa. Concrete testing included compressive strength tests carried out at 3 days, 7 days, 14 days, 28 days, 42 days and 56 days. Before making concrete samples, the mortar compressive strength is tested first by varying the boiler crust ash content by 0%, 15%, 25%, 35%, and 50% to obtain the optimum mixture. Based on the results of the analysis of compressive strength mortar obtained the optimum mixture of 15% for the manufacture of concrete that will be compared with normal concrete. The compressive strength of concrete with the optimum mixture at 28 days is 24.44 Mpa more than the compressive strength of the 23 Mpa plan. Concrete that has the highest compressive strength occurs at the age of 56 days is concrete with the normal mixture with a compressive strength of 34.44 Mpa higher than the compressive strength of concrete with an optimum mixture of 15% boiler crust ash which is 28.51 MPa.

scholarly journals Analysis of Petro-Physico-Mechanical Properties of Coarse Aggregate and Its Implications on the Performance Characteristics of Concrete

2020 ◽  
pp. 45-60
Author(s):  
Larry Pax Chegbeleh ◽  
Lawrence Opanin Nkansah ◽  
Frank Siaw Ackah ◽  
Richard Adams Mejida
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Coarse Aggregate ◽  
Aggregate Size ◽  
Performance Characteristics ◽  
Rock Samples ◽  
Rock Types ◽  
Strength Tests ◽  
Compressive Strength Of Concrete ◽  
The Impact

The importance of concrete as one of the major materials in the building and construction industry cannot be over emphasized due to the myriad benefits and versatility to humankind. However, its performance characteristics on the stability of engineered structures have mostly been overlooked. In this paper, petrographic characteristics and physico-mechanical properties of ten (n=10) rock samples and some quantity of coarse aggregate representing one set of samples, each obtained from two quarry sites around Amasaman and Shai Hills in the Greater Accra Region of Ghana, have been investigated. This study aimed to determine the impact of aggregate size, content and type on the compressive strength of concrete. The study was conducted through petrographic and physico-mechanical properties analyses on the samples obtained. Petrographic studies were performed on the ten (n=10) rock samples from each quarry site, while the physico-mechanical property tests were conducted directly on the coarse aggregate. However, compressive strength tests were performed on cast concretes produced from aggregates with varying sizes and type obtained from the two quarry sites. Results of the petrographic analysis reveal two rock types: Quartzo-feldspathic gneiss and Granodiorites from Amasaman quarry and also two rock types: Gneiss and Meta-granite from Shai Hills quarry. Results of the physico-mechical properties tests are consistent with requirement of approved construction standards. Compressive strength tests show increasing compressive strength of concretes with increasing aggregate nominal sizes of classes A, B and C but show reduced compressive strength for aggregate nominal sizes of class D. It can therefore, be inferred that, aggregate size and content have profound impact on compressive strength of concrete. Also, aggregate type has influence on compressive strength of concrete, as observed in higher compressive strength of concretes produced from the quartzo-feldspathic gneiss and granodiorites than concretes produced from the gneiss and meta-granites.

scholarly journals MODERN LAMINATE COMPOSITE DESIGNED FOR AIRCRAFT CONSTRUCTION

2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Izabela Korzec ◽  
Jacek Czarnigowski ◽  
Tomasz Łusiak ◽  
Daniel Rękas ◽  
Mateusz Marciniak ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Laminate Composite ◽  
Structural Elements ◽  
Propeller Blade ◽  
Strength Parameters ◽  
Laminate Composites ◽  
Strength Tests ◽  
Basic Strength

The article presents modern laminate composites designed for aircraft structural elements based on ECC e461 symmetric fabric and Interglas 02037 symmetric fabric with MGS L285/H285 resin. These composites differ in the weave used and the type of fabric. The article presents basic strength parameters of the composite obtained as a result of stand tests. The results of compressive strength tests of the material samples are presented. It was shown that the weave of the fabric significantly affects the strength parameters of the composite. The change of the weave caused the increase in strength by more than 65%. The possibilities of application of this material on selected structural elements of aircraft such as: propeller blade plating, masts, shavings, pylons.

scholarly journals PENGARUH METODE PERLAKUAN DALAM PERAWATAN BETON TERHADAP KUAT TEKAN DAN DURABILITAS BETON

2019 ◽  
Vol 9 (2) ◽  
pp. 47-54
Author(s):  
Fepy Supriani ◽  
Mukhlis Islam
Keyword(s):  
Compressive Strength ◽  
Fresh Water ◽  
Concrete Strength ◽  
Mix Design ◽  
Concrete Compressive Strength ◽  
Treated Water ◽  
Several Variables ◽  
Constituent Material ◽  
Strength Tests ◽  
Compressive Strength Of Concrete

Concrete strength is influenced by several variables, among others by its constituent material, mix design, workmanship, and curing. The objective of concrete curing is to maintain the concrete in certain conditions after the dismantling of the formwork hence the optimization of concrete strength can be achieved close to the designed strength. This study aims to determine the effect of concrete curing on its compressive strength. Designed concrete compressivestrength of 20 MPa with slump values of 60-100 mm to be used. The specimens are cube-shaped with 15 cm dimension. Concrete compressive strength tests were conducted at 28 days and 56 days of concrete age. The types of concrete curing consist of 9 variations, i.e., not treated, water immersed and water sprinkling. Optimum 28 days age of compressive strength of concrete obtained from specimens that immersed in fresh water, which was 31,3 MPa. The concretespecimens that were put outdoor without any curing and treatment generates second highest compressive strength value of 28.6 MPa. The 28 days age of concrete compressive strength values cured with water sprinkling with addition of burlap wrapping are still under the compressive strength of uncured concrete. Significant changes to the strength of cured concrete occurred at age of 56 days and uncured concrete strength decreased up to 19%. The optimum increase occurred in concrete cured with burlap sack wrapping and water sprinkling that was conducted routinely for 3 days by 27,84%. With increasing age (durability) the treated concrete has better strength.

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