scholarly journals Quality Assessment of Clay for Limestone Calcined Clay Cement Production

2020 ◽  
Vol 5 (8) ◽  
pp. 1675-1680
Author(s):  
Aditya Singha ◽  
Pradyumna Dashora
Keyword(s):  
High Temperature ◽  
Quality Assessment ◽  
Quality Standards ◽  
Cementitious Materials ◽  
Developing Economy ◽  
Cement Production ◽  
Distant Future ◽  
Calcined Clay ◽  
Basic Segment ◽  
Synthetic Procedure

Being the biggest material utilized by humanity after water, concrete and related businesses have grind sway on development and improvement of a nation. Despite the fact that generally modest, the way toward making its fixings produces CO2. The significant offer for this natural issue from concrete is because of the creation of concrete which is a basic segment. Discharges from concrete creation are predominantly because of development of clinkers which are fundamentally concrete knobs which blend and crush with gypsum to deliver Ordinary Portland concrete C (OPC). It requires the crude materials to be warmed at high temperature (up to 1500°) to create clinker. The synthetic procedure associated with clinkerization where the limestone changes into lime and CO2 is answerable for 50-75 % of outflow. Utilization of electrical vitality required to pound the crude materials likewise contributes its offer. Because of the raising worry against the ozone harming substance discharges and a dangerous atmospheric deviation, ventures and nations are encouraged to see vital strides to check this worldwide issue. It is evaluated that concrete industry is liable for around 6-8% of worldwide CO2 outflow. As it is the quickest developing economy and amongst the most populated nations on the planet, India is about to turn into the biggest shopper of concrete in not so distant future by surpassing China. Because of exponential consumption of value crude materials just as ecological issues from the customary OPC creation, it is critical to take a gander at substitute approaches to deliver the folio in India. The most well-known and broadly acknowledged technique is clinker substitution by strengthening cementitious materials (SCMs). As significant piece of the electrical vitality in the nation originates from coal based warm force plant, which produces fly debris, a SCM all in all; a great deal of examination has been done in the use of fly debris in concrete creation. As of now according to the Bureau of Indian Standard (BIS), 30-40% of clinker can be supplanted with fly debris which meets the necessary quality standards. Despite the fact that, because of the absence of accessibility great quality fly debris and different government guidelines, the complete piece of the overall industry of fly debris based PPC in India, is around 65% as it were.

scholarly journals Special Issue: Supplementary Cementitious Materials in Concrete, Part I

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2291
Author(s):  
Alessandro P. Fantilli ◽  
Daria Jóźwiak-Niedźwiedzka
Keyword(s):  
Environmental Impact ◽  
Portland Cement ◽  
Building Materials ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Special Issue ◽  
Cement Production ◽  
Concrete Part

The environmental impact of the Portland cement production and the large use of cement-based building materials is a growing problem [...]

scholarly journals 3D printing of calcined clay-limestone-based cementitious materials

2021 ◽  
Vol 149 ◽  
pp. 106553
Author(s):  
Yu Chen ◽  
Shan He ◽  
Yu Zhang ◽  
Zhi Wan ◽  
Oğuzhan Çopuroğlu ◽  
...  
Keyword(s):  
3D Printing ◽  
Cementitious Materials ◽  
Calcined Clay

Research Progress on the Hydration of Portland Cement with Calcined Clay and Limestone

2021 ◽  
Vol 1036 ◽  
pp. 240-246
Author(s):  
Jin Tang ◽  
Su Hua Ma ◽  
Wei Feng Li ◽  
Hui Yang ◽  
Xiao Dong Shen
Keyword(s):  
Mechanical Properties ◽  
Portland Cement ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Research Progress ◽  
Hydration Reaction ◽  
Hydration Products ◽  
Early Hydration ◽  
Calcined Clay ◽  
Dense Microstructure

The use of calcined clay and limestone as supplementary cementitious materials, can have a certain influence on the hydration of Portland cement. This paper reviewed the influence of limestone and calcined clay and the mixture of limestone and calcined clay on the hydration of cement. Both limestone and calcined clay accelerate the hydration reaction in the early hydration age and enhance the properties of cement. Limestone reacts with C3A to form carboaluminate, which indirectly stabilized the presence of ettringite, while calcined clay consumed portlandite to form C-(A)-S-H gel, additional hydration products promote the densification of pore structure and increase the mechanical properties. The synergistic effect of calcined clay and limestone stabilize the existence of ettringite and stimulate the further formation of carboaluminate, as well as the C-(A)-S-H gel, contributed to a dense microstructure.

Performance of Impure Calcined Clay as a Pozzolan in Concrete

2020 ◽  
pp. 036119812095314
Author(s):  
Khashayar Jafari ◽  
Farshad Rajabipour
Keyword(s):  
Portland Cement ◽  
Drying Shrinkage ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Strength Development ◽  
Natural Pozzolan ◽  
Quartz Content ◽  
Calcined Clay ◽  
Air Content ◽  
Sand And Gravel

Supplementary cementitious materials (SCMs) are natural or industrial by-product materials which are used to improve the performance, durability, and sustainability of concrete mixtures. Motivated by the recent reports on shortage of conventional SCMs, impure calcined clays (CCs) are receiving attention as abundant alternative pozzolans for concrete. In this study, a clay slurry resulting from washing aggregates in a commercial sand and gravel pit was investigated. This source clay was dried and calcined, and the properties and pozzolanic performance of the resulting CC was evaluated. It was observed that despite having a large (>50%wt.) inert quartz content, the CC met all ASTM C618-19 (AASHTO M295) requirements for natural pozzolan. A pavement-grade concrete mixture containing 20%CC as a cement replacement (by weight) produced desired workability and fresh and hardened air content. Strength development was slightly below the control. The use of CC improved the durability of concrete with respect to chloride penetration, alkali–silica reaction, and drying shrinkage in comparison with a control (100% Portland cement) mixture. In addition, ternary limestone-calcined clay–cement and slag-calcined clay–cement mortar mixtures showed excellent strength development while replacing nearly 50% of the Portland cement.

scholarly journals Influence of Milling Techniques on the Performance of Wheat Straw Ash in Cement Composites

2020 ◽  
Vol 10 (10) ◽  
pp. 3511
Author(s):  
Abdul Qudoos ◽  
Ehsanullah Kakar ◽  
Atta ur Rehman ◽  
In Kyu Jeon ◽  
Hong Gi Kim
Keyword(s):  
Particle Size ◽  
Wheat Straw ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Hydration Reaction ◽  
Cement Composites ◽  
Cement Production ◽  
X Ray ◽  
Worldwide Production ◽  
Straw Ash

The worldwide production of cement is growing every year due to its increased use in the construction. Cement production is affiliated with an environmental concern as it contributes to the CO2 emissions. It is imperative to reduce the cement production by incorporating supplementary cementitious materials in the cement composites. In this research study, wheat straw ash (WSA) was used as an alternate of ordinary Portland cement. The ash was ground separately with a ball mill and a disintegrator mill as well as with a combination of both to enhance its pozzolanic efficiency. Mortar and paste specimens were made by substituting cement with WSA (20% by weight). Ash specimens were examined in terms of particle size distribution, X-ray diffraction, and X-ray fluorescence analyses. The performance of the ash specimens in cement composites was examined via compressive and flexural strengths, and ultrasonic pulse velocity (UPV) tests. Isothermal calorimetric, thermogravimetric analyses (TGA), mercury intrusion porosimetry (MIP), and scanning electron microscopy (SEM) were also employed on the specimens. The results revealed that the particle size of the wheat straw ash specimens significantly reduced and specific surface area enhanced when ground with a combination of both milling techniques. Cement composites made with this type of ash demonstrated improved mechanical and physical properties, accelerated hydration reaction at the early ages, reduce calcium hydroxide content at the later ages, and densified microstructure.

scholarly journals Production of Ultra-High-Performance Concrete with Low Energy Consumption and Carbon Footprint Using Supplementary Cementitious Materials Instead of Silica Fume: A Review

Energies ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 8291
Author(s):  
Mays A. Hamad ◽  
Mohammed Nasr ◽  
Ali Shubbar ◽  
Zainab Al-Khafaji ◽  
Zainab Al Masoodi ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Silica Fume ◽  
High Performance ◽  
High Performance Concrete ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Ultra High Performance Concrete ◽  
Cement Production ◽  
Granulated Blast Furnace Slag ◽  
The Impact

The increase in cement production as a result of growing demand in the construction sector means an increase in energy consumption and CO2 emissions. These emissions are estimated at 7% of the global production of CO2. Ultra-high-performance concrete (UHPC) has excellent mechanical and durability characteristics. Nevertheless, it is costly and affects the environment due to its high amount of cement, which may reach 800–1000 kg/m3. In order to reduce the cement content, silica fume (SF) was utilized as a partial alternative to cement in the production of UHPC. Nevertheless, SF is very expensive. Therefore, the researchers investigated the use of supplementary cementitious materials cheaper than SF. Very limited review investigates addressed the impact of such materials on different properties of UHPC in comparison to that of SF. Thus, this study aims to summarize the effectiveness of using some common supplementary cementitious materials, including fly ashes (FA), ground granulated blast furnace slag (GGBS), metakaolin (MK) and rice husk ashes (RHA) in the manufacturing of UHPC, and comparing the performance of each material with that of SF. The comparison among these substances was also discussed. It has been found that RHA is considered a successful alternative to SF to produce UHPC with similar or even higher properties than SF. Moreover, FA, GGBS and MK can be utilized in combination with SF (as a partial substitute of SF) as a result of having less pozzolanic activity than SF.

Sign in / Sign up

Export Citation Format

Share Document