It is always desirable to use the best cement in constructions. Therefore, the properties of a cement must be investigated. Although desirable cement properties may vary depending on the type of construction, generally a good cement possesses following properties (which depend upon its composition, thoroughness of burning and fineness of grinding).
Provides strength to masonry. Stiffens or hardens early. Possesses good plasticity. An excellent building material, Easily workable. Good moisture-resistant.
Proper field tests and laboratory tests should be done to ensure the qualities of the cement. Related Articles:
Physical & Chemical Properties of cement What is Cement? Cement Composition Cement Manufacturing Process Uses of Cement Raw Cement Ingredients Properties of Good Cement Field Test of Cement What is Hydraulic Cement? Hydraulic Cement Uses How to Apply Hydraulic Cement
- 0.1 What are the parameters of cement?
- 0.2 What makes a good quality brick?
- 0.3 Which cement is best for brick?
- 0.4 What grade concrete is best?
- 1 What is characteristic strength of concrete?
What are the parameters of cement?
Chemical Analysis of the Parameters Determining the Quality of a Case of Cement from Cement Sold on the Mbuji-Mayi Markets Kayembe Meji Jean Pierre 1*, Ntshila Kamaje Alexis 2, Kabeya Luboya Christophe 3, Ciamala Mukendi Paul 4 1 Laboratory Techniques Section, Higher Institute of Medical Techniques of Mbuji-Mayi, Mbuji-Mayi, Democratic Republic of the Congo,2 Department of Chemistry, Higher Institute of Medical Techniques, Mbuji-Mayi, Democratic Republic of Congo,3 Nursing Section, Higher Institute of Health Sciences of the Red Cross, Mbuji-Mayi, Democratic Republic of Congo,4 Section of Nursing Sciences, Higher Institute of Pedagogy of Mbuji-Mayi, Mbuji-Mayi, Democratic Republic of Congo,
- DOI: 10.4236/oalib.1106966 PDF HTML XML 183 Downloads 1,402 Views Abstract This study aims to assess the quality of cement used in civil engineering.
- We have used the following approaches and techniques for data analysis: calcination conydexiométrie gravimetric and photometric.
- The results show that as regards the content of SO 3, MgO, Cao and alkali oxide, the cements are within the limits of the standards required by the Congolese Control Office (OCC).
In view of these results, the conclusion is that the cements used in Mbujimayi can be effectively put to several uses that do not require special cements. Share and Cite: Pierre, K.M.J., Alexis, N.K., Christophe, K.L. and Paul, C.M. (2021) Chemical Analysis of the Parameters Determining the Quality of a Case of Cement from Cement Sold on the Mbuji-Mayi Markets. 1. Introduction Unfortunately the province of Kasai Oriental does not produce cement despite its multiple projects on Katanda and Bakodile limestone. Thus it is obliged to import cement from other provinces and from outside of the country. In the markets of the town of Mbuji-Mayi, one can find cement from the following cement factories: ・ Lukala cement ・ Lubudi cement ・ Cement in Chilanga ・ Kalemie cement ・ Es Pagnole cement plant These cements used in several construction sites in the city of Mbuji-Mayi are sometimes the subject of piracy, by some ill-intentioned sellers by adding either sand, or ashes from the calcination, thus distorting the parameters of the firewood d ‘a good cement.
This sensitive denatured cement can negatively influence the construction works, thanks to which, we proposed to study six parameters which determine the quality of a good cement by the standards of the Congolese Control Office (acronym OCC), which are those of the American company A.STM: US Society for Testing of Materials.
The objective we are pursuing by studying these different parameters is to determine whether the cement sold on the Mbuji-Mayi market is of good quality. For the parameters to be studied the standards set at the following limits, one can never go beyond ser: ・ 0.85% ± 0.15% insoluble residue ・ 4.00% ± 0.25% of fire losses ・ 2.00% ± 0.10% sulfur trioxide ・ 5.00% ± 0.40% magnesium oxide To these values, we added the limits of certain parameters that we could not bypass according to Wilfred (2005); they are: 57% to 70% for calcium oxide, 1% for alkaline oxides, in this case sodium and potassium oxide,
We must note that the quality of a good cement depends on four previous settings. For this study, we used quantitative analysis techniques such as: gravimetry; the flame of complexiometry and photometry. Since our study is about cement, it is good to talk briefly about this building material.2. Cement 2.1.
Definition Cement can be defined in different ways: as a binder or a thermodynamically unstable and more soluble body system which, in the presence of water, gives a saturated solution, which will crystallize spontaneously causing setting and forming a more stable system; or powder of an alternative binder resulting from the firing at high temperature (1400˚C to 1500˚C) of a carefully measured mixture of clay and limestone,2.2.
Types of Cements and Their Behavior There are several types of cement which can be grouped into two categories: 2.2.1. Aerial Cement 1) Cement of anhydrite It is prepared from natural gypsum at a temperature of 600˚C to 700˚C as a mixture with catalyzed curing: CaO; (N a +, Cu 2+, Fe 2+ )SO 4 ; fired dolomite, alkaline slag is a slow-setting cement that comes on after thirty minutes and ends after twenty-four hours.
It is used for masonry mortars, 2) Antacid cement It is a cement which contains within it calcium carbonate and clay injected with a liquid glass there are also certain anti-acid substances such as quartz, sodium fluorine silicate (Na 2 SiF 6 ) with 0.5% linseed oil and 2% ceresite is a normal, hydrophobic, chemical resistant hardening cement is used in the insulation of chemical refractories in acid absorption towers as well as in chemical industry premises.2.2.2.
Hydraulic Cement 1) Roman cement They are pure dolomitic marls and boiled with 25% clay impurities, 15% of mineral additives and 5% natural gypsum (CaSO 4 ∙2HO 2 ) is a slow-setting cement and low resistance Its hydraulic modulus varies between 1.1 to 1.7 Its setting begins after 15 minutes and ends after 24 hours.
It is used for plaster and masonry, inferior concrete and for wall stones and small blocks,2) Portland cement pozzolamic It is a clinker pulverized with hydraulic substances varying from 20% to 50% mixed with various industrial siliceous wastes and volcanic ash.
It is a sedimentary which contains 30% diatomite and tripoli and has a slow. During its hardening, it undergoes two processes; hydration of mineral clinker and the interaction of active mineral admixture with calcium hydroxide to resist water and is used for the construction of works underwater and in circles with high temperature variation.3) Slag cement It is a cement for granulated blast furnace slag (cast iron waste) It has spontaneous hardening under water and higher resistance to water, humidity and frost It is used in hydraulic constructions in humid environment as well as in constructions subject to frost and humidity and drying.4) Aluminous cement It is a mixture of bauxite and baked lime with a preponderance of low alkalinity calcium aluminate and 2% mineral additives.
It is a fast hardening cement (30 minutes and ends after 12 hours) and good physical properties―mechanical. It is used for restoration works of dams, pavements, foundations, buffering of oil and gas probes, as well as lining of mine shafts, tunnels.5) Portland cement It is a cement composed of approximately 75% calcium carbonate and 25% clay and a little gypsum after clinkerization.
This cement produces hard, air-stable and frost-resistant cement products. It is used in several areas depending on their varieties.6) The expansive elements This is aluminous cement containing calcium aluminate and a high alkalinity of about 30% natural gypsum. Volume increases when cured in humid conditions and without suffering shrinkage.
It is used for the restoration of damaged concrete constructions as well as for the hydraulic insulation of tunnels and mine shafts also in underground constructions.3. Experimental Study 3.1. Chemical Analysis of Samples In our study, our attention is focused on the quantitative determination in different types of cement, can the parameters confer the harmful properties related to their use in the building according to the American standard (ASTM) such as the OCC the currently using.
The physical-chemical laboratory of the Higher Pedagogical Institute of Mbuji-Mayi and that of Biopharco served as a research framework.3.2. Sampling To begin our study, we have for years no preference, the specimens collected are samples taken from our various markets in the city of Mbuji-Mayi; in the province of Kasai Oriental.
For this purpose, we collected four types of cement from any city: white cement from Spain, Chilanga cement from Zambia, Lukala cement and cement in Lubudi; which constitute our sample. We did not find in the Kalemie cement market and the Likasi cement plant.
Our sample was taken in a single day in August of the year 2019.3.3. Prepare and Processing of the Sample After harvest, our samples were weighed and then broken up into cement solutions according to the following procedure : ・ weigh two grams of sample in a 250 cc beaker, ・ mix with 20 cc of distilled water while stirring, ・ add 20 cc Hcl 1.19 density and 37%, ・ heat gently for 10 to 15 minutes, ・ dilute the solution with 35 ml of distilled water, ・ allow to digest for 15 minutes at a temperature just below the boiling point, ・ filter through filter paper (medium temperature: slow filtration), ・ wash two to three times with lukewarm distilled water each time the filter paper turns yellow, ・ the filtrate (stock solution) obtained is used for the determination of the parameters and the residue for the determination of the insolubles.3.4.
Materials and Devices Throughout our analyses, we used the following different materials and devices: ・ Volumetric flasks of 500 and 250 ml ・ pipette (±0.05 ml) 10 ml and 25 ml ・ Digital MLA variable volume micropipette (50 and 200 ml) ・ -Γραδυατεδ feet 50 ml and 250 ml ・ porcelain crucibles ・ plastic capsules ・ beakers of 200 and 400 ml ・ a crystallizer ・ ft nces ・ a squeeze bottle ・ a desiccator ・ Ashless medium texture quantitative filter papers ・ a precision electronic analytical balance of the baxtran type (±0.001) ・ a CG818 pH meter ・ a VULCAN type muffle furnace ・ a Prolabo type oven ・ a magnetic stirrer + magnetic bar ・ a Ciba Corning 410 type flame photometer (0 to 100 ppm) 3.5.
Reagents During our operations, for our analyses, we used the following reagents: ・ Concentrated hydrochloric acid (1.19; 37%), ・ 10% barium chloride, ・ potassium cyanide, ・ chloride with ammonium hydroxide, ・ EDTA 0.01 M, ・ distilled water, ・ potassium hydroxide, ・ the NET, ・ the solution of Patton and Raeder 1%, ・ the buffer solution at pH 10 NH 3 and NH 4 Cl, ・ the standard solution (mixed) based on sodium (2989.6 ppm) and potassium (207 3p pm).3.6.
Techniques and Methods Used for Laboratory To arrive at the results of our research, we used the following techniques and methods: the calcination furnace, the filter paper filter, gravimetry, complexiometry and flame photometry. The results of our study are presented in Table 1, Table 1, Results of four cement samples. the literature according to A-Komar and therefore WILFRED W. Scott cements are consumables.4. Interpretation of Results After our analyzes on four cement samples taken from soils in Mbuji Mayi, and comparing them to the table above, our samples individually did not fully meet the values set by the ASTN WILFRED i.e.
standard in the book entitled “Standard method of chemical analysis” used by the OCC, which states that a cement is declared compliant if it meets the following conditions: ・ insoluble residues: 0.85% ± 0.15% ・ παρ your fire: 4.00% ± 0.25% ・ συλfυρ dioxide: 2.00% ± 0.10% ・ Magnesium oxide: 5.00% ± 0.40%.
We added the limits of two parameters that could not be bypassed according to WILFRED, they are calcium oxide: 63.5% ± 6.5%. And all the sodium and potassium oxide does not exceed 1% content according to Komar. The cement produces Spanish, white cement apart from the fire losses and insoluble residues whose content slightly exceeds the limits or 4.79 and 1.31 for 4.00 and 0.85 set by the OCC/ASTM, other parameters, the excess of which can influence the quality of the cement, are within the limits of sulfur trioxide, magnesium oxide, and alkali oxides.
According to OCC/ASTM, other parameters of which their exc Sc little wind influence the quality of the cement, also fall within the limits. I is sulfur trioxide, magnesium oxide and alkali oxides. Thus according to OCC/ASTM, the product does not comply. But the literature tells us that the existence of insoluble matter shows the presence of heavy metals such as lead, uranium or its derivatives, etc.
which, therefore, can be radioactive and have harmful effects on the human body later on. that is, their content exceeds the authorized threshold. As for the losses on fire, we will say that it can be a question of poor packaging of products that could have captured humidity or a possible infiltration of foreign bodies after machining, just as we can think of an orchestrated mafia by sellers.
Lukala cement showed almost the same behavior as white cement, its insoluble substance content is 3.75 to 0.85 determined by OCC/ASTM which disqualifies it, but all radical parameters are good that is to say meet the standards, so according to KOMAR it is a cement that has no unhealthy effects such as causing the expansion or swelling of the hardened cement or even delaying the setting or on the contrary it is―that is to say cause sudden sets of the cement paste.
Lubudi cement can undergo the same according to ASTM standards, due to the excessive values of insoluble matter; the losses on ignition give respectively 5.79 and 9.47 for 0.85% and 4.00% and sulfur trioxide, which slightly exceeds the limit set is 2.13 to 2.00 according to the standards.
- As this cement is a Portland clinker cement, its results are within a range of 0 to 5% MgO and 0 to 1% for alkaline oxides and between 1.5 and 3.5 for SO 3,
- According to KOMAR, their higher content reduces the quality of the cement.
- Magnesium oxide fired at a temperature of about 1500˚C and subjected to the action of water, slowly moves away causing the appearance of cracks in the mortar or in already hardened concrete, this is why its content should not exceed 5%.
The presence of alkaline oxides in amounts greater than 1% can destroy hardened concrete. A high content of SO 3 from gypsum or coal ash causes the following phenomena: ・ the variation in the volume of the cement during its hardening, ・ if the hardening takes place in air, the evaporation of the water leads to a decrease in volume and conversely, the hardening takes place under water, the opposite phenomenon is observed, to know its swelling.
- A particularly dangerous phenomenon is the shrinkage (decrease in volume) which can lead to cracking of the hardened concrete, thus, the cement of Lubudi in view of its results described in the table above is a compliant product for construction.
- Chilanga cement fulfills the same conditions as other cements, that is to say; it can be, according to the standards of the American society for testing materials that the OCC considers, said poorer therefore not compliant, but this cement has no adverse effects in construction especially the last four parameters which affect the mechanical quality of the cement are within acceptable limits (see table).
The levels of calcium oxides, substances predominant in cement, always accompanied by magnesium, meet the weight requirements according to our analysis and also as reported by A and IP KOMAR MOUKHELENON in their books which indicate that calcium oxide is found in cement in proportions varying between 62% and 67%, or 57% to 70% according to WILFRED W SCOTT (63.5% on average).
Taking into account these interpretations according to the OCC/ASTM standards, we confirmed that the four cements studied are of good quality despite the two parameters (insoluble residues and loss on ignition) give results which differ significantly in percentage; these differences are insignificant if we consider at the outset all the parameters of our study.
They may suggest the presence of certain heavy metals, either humidity or a case of adulteration, but this does not affect the mechanical quality of the cements studied and the population can use it.5. Conclusions Our study consisted of studying the key parameters that determine the quality of a target cement.
- We have six parameters which are the content of insoluble residues in heat loss, sulfur oxide to magnesium oxide, calcium oxide and alkali oxides.
- Our samples were taken from the markets of Mbuji-Mayi during the period of August 2019 and we were able to collect 4 types of cement from the following cement: Lukala cement, Lubudi cement, Chilanga cement and the Spanish cement factory.
We subjected these cements to analyze which gave us the following results as indicated in the table above. All these four types of cement with regard to the content of SO 3, MgO, CaO and alkali oxides are within the limits of the required standards. But with regard to the insoluble matter content, the results found strongly deviate from the standards set by the OCC; this can be explained by the presence of certain heavy metals that some researchers will be able to study later.
The white cement and that of Lukala present a value which deviates slightly from the fixed standards. And the Lukala cement is within the tolerated limits of 4.16 ± 0.001, 4.00 ± 0.25 required by the OCC/A STM while the Lubudi cement and that of Chilanga do not deviate very significantly. In view of all these results, we can conclude that the cements can be used with more or less a certain efficiency for several uses which do not require special cements.
Conflicts of Interest The authors declare no conflicts of interest regarding the publication of this paper.
What are the requirements for good cement and good brick?
Characteristics of Good Bricks It is always desirable to use the best quality brick in constructions. Therefore, the Characteristics of a good brick must be investigated. Generally good bricks possesses following properties-
Bricks should be uniform in color, size and shape. Standard size of brick should be maintained. They should be sound and compact. They should be free from cracks and other flaws such as air bubbles, stone nodules etc. with sharp and square edges. Bricks should not absorb more than 1 ⁄ 5 of their own weight of water when immersed in water for 24 hours (15% to 20% of dry weight). The compressive strength of bricks should be in range of 2000 to 5000 psi (15 to 35 MPa). Salt attack hampers the durability of brick. The presence of excess soluble salts in brick also causes efflorescence. The percentage of soluble salts (sulphates of calcium, magnesium, sodium and potassium) should not exceed 2.5% in brunt bricks. Brick should not change in volume when wetted. Bricks should neither overburnt nor under-brunt. Generally, the weight per brick should be 6 lbs. and the unit weight should be less than 125 lbs. per cubic ft. The thermal conductivity of bricks should be low as it is desirable that the building built with them should be cool in summer and warm in winter. Bricks should be sound proof. Bricks should be non-inflammable and incombustible. Bricks should be free from,
tags: properties of bricks, qualities of bricks, good brick, best bricks, good bricks, brick properties, brick property, brick qualities, brick quality, properties of bricks in construction, requirements of good brick, WHAT ARE THE QUALITIES OF GOOD BRICKS?, Qualities of a good brick : Characteristics of Good Bricks
What makes a good quality brick?
Good quality bricks should be well-burnt, as well as having a uniform colour. If bricks are under-burnt or over-burnt, they lose this uniformity. Brick earth – brick earth should be free from physical materials such as stones and pebbles, as well as chemicals like potassium nitrate.
Which cement is best for brick?
Recommended Use of PPC cement – Flyash based cement (PPC) is recommended for brick masonry, plastering, tiling and waterproofing works. In these works, strength is not the major criteria. PPC has an edge on OPC as PPC has slower rate of heat of hydration.
What grade concrete is best?
High-Performance Strength Concrete Grades – C30 Concrete Grade One of the lower strength commercial grades is C30. Also known as ST3 or PAV1, C30 grade is mostly used during pavement construction. C30 is designed to withstand 30 Newton/28 day strength and is strong enough to use in reinforced bases, any outside paved area, or other lighter external applications.
C35 Concrete Grade C35 or PAV2 is designed to withstand 35 Newton/28 day strength. Offering more substantial strength than C30 grade, C35 can be used on larger commercial buildings and foundations for added support. C35 also has special additives to reduce the likeliness of air bubbles forming, protecting against surface cracks from freezing temperatures.
C40 Concrete Grade C40 is an extremely strong commercial-grade concrete with 40 Newton/28 day strength. C40 is the ideal choice in the construction of large industrial support beams and foundations. It is also used in a variety of roadwork applications and agricultural yards.
- When using concrete in any construction project, it’s important to know which particular grade will best suit your application.
- By better understanding the concrete grade system, you’ll be able to make the right choice for the job at hand and ensure you have a strong finished product that will last.
- Family owned and operated since 1969, Knight’s Companies is a concrete company in Columbia, SC.
Knight’s upholds the highest standards in all aspects of the business, and will complete commercial concrete jobs other companies won’t even quote. : Different Concrete Grades and How They’re Used | Concrete Columbia SC
What is concrete and its characteristics?
Concrete types, characteristics and applications. Concrete – a mixture of cement, aggregates, additives and water that creates a homogeneous and compact mass – is a durable, resistant and versatile material that is used in multiple construction projects.
What is characteristic strength of concrete?
The characteristic strength of concrete is defined as that compressive strength below which not more than.Q. The characteristic compressive strength of concrete is found to be 0.79 times of its mean compressive strength. If variance is 14.5, find the grade of concrete.
What are the characteristics of high strength concrete?
High-Strength Concrete High-performance concrete is a term used to describe concrete with special properties not attributed to normal concrete. High-performance means that the concrete has one or more of the following properties: low shrinkage, low permeability, a high modulus of elasticity, or high strength.
- According to Henry Russell, ACI defines high performance concrete as “concrete that meets special performance and uniformity requirements that cannot always be achieved routinely by using only conventional materials and normal mixing, placing, and curing practices.
- The requirements may involve enhancements of placement and compaction without segregation, long-term mechanical properties, early-age strength, toughness, volume stability, or service life in severe environments” (Concrete International, p.63).
High-strength concrete is typically recognized as concrete with a 28-day cylinder compressive strength greater than 6000 psi or 42 Mpa. More generally, concrete with a uniaxial compressive strength greater than that typically obtained in a given geographical region is considered high-strength, although the preceding values are widely recognized.
- Strengths of up to 20,000 psi (140 Mpa) have been used in different applications,
- Laboratories have produced strengths approaching 60,000 psi (480 Mpa).
- High-strength concrete can resist loads that normal-strength concrete cannot.
- Several distinct advantages and disadvantages can be analyzed.
- It is important to consider all peripheral results of selecting high-strength concrete since special considerations must be addressed beyond strength properties.
Once it is decided to use high-strength, high-performance concrete, the mix design and production process can begin. The materials used and concepts involved in increasing the strength of concrete must be clearly understood in order to obtain the desired properties.
- Testing is an integral step in the production process, since quality control studies show that slight changes in mixture proportions can lead to large changes in the compressive strength of concrete.
- When the design proportioning is complete, mixing can commence with extra consideration for workability and related properties of the mix.
Once the high-strength concrete is placed, the hardened concrete properties can be predicted in addition to its special characteristics. Some of the properties slightly differ from concrete with lower strength while some vary more significantly. In order to examine the performance of high-strength concrete in practice, several case studies can be investigated.