Research on the combined substitution of supplementary cementitious materials (SCMs) has already demonstrated that it might be one few viable options to produce low-carbon concrete at scale. This paper presents an experimental investigation performance and durability rice husk ash (RHA) calcined clay (CC) in ternary blended exposed chloride attacks under wet/dry cycles. Portland cement (PC) was replaced by RHA CC up 50% weight concrete. Samples were subjected cycles 3.5% NaCl water, with...

Blended cements are preferred to Ordinary Portland Cement (OPC) in construction industry due costs and technological environmental benefits associated with them. Prevalence of significant quantities carbon dioxide (CO 2 ) the atmosphere increased industrial emission is deleterious hydrated cement materials carbonation. Recent research has shown that blended more susceptible degradation carbonation than OPC. The ingress CO within porous mortar matrix a diffusion controlled process. Subsequent...

Due to rapid industrialization, urbanization, and surge in modern human activities, water contamination is a major threat humanity globally. Contaminants ranging from organic compounds, dyes, inorganic heavy metals have been of concern recent years. This necessitates the development affordable remediation technologies improve quality. There growing interest nanotechnology recently because its application eco-friendly, cost-effective, durable material production. study presents review...

In Kenya fired clay bricks are mainly used as construction materials. However, vast quantities of these Fired Rejected Clay Bricks (FRCB) generated rejected annually a result improper calcination or demolition housing units made bricks. These FRCB largely disposed off in open fields leading to land pollution. This paper reports the experimental findings on performance Limestone Calcined Cement (LC3). The test cement was prepared by blending and inter-grinding clinker, FRCB, limestone gypsum....

In this work, the factors controlling fresh state properties of limestone calcined clay cement (LC3) are assessed and compared to Portland binary cements, extending scope previous research by combining rheological measurements with setting time determination evaluation plastic shrinkage a novel method. Yield stress elastic modulus considered indicators for structural build-up/breakdown process when is applied system. On other hand, occurs from mixing paste plays an important role in...

This paper presents findings of an experimental investigation on sodium sulphate (Na2SO4) activated calcined clay - Portland cement blends in sulphuric acid media. Calcined clays were blended with Ordinary Cement (OPC) at replacement levels 40% 45% and 50 % by mass OPC to make labelled PCC40, PCC45 PCC50 respectively. Initially, pozzolanicity setting time tests conducted. Mortar prisms measuring 40 mm × 160 cast using 0.5M Na2SO4 solution their compressive strengths determined the 2nd, 7th,...

Most of concrete structural failures are attributed to poor workmanship and engineering designs. Some microorganisms present in sewer systems can degrade the and/or mortar. Concrete due microbial attack has not attracted much attention especially developing countries such as Kenya. This study investigated effect Thiobacillus intermedius bacteria on performance Ordinary Portland Cement (OPC). Preparation test mortar prisms was done using bacterial solution either mix water, curing water or...

Malawi is one of the least-developed countries in Sub-Saharan Africa with disaster-prone housing infrastructure characterized by poor construction materials. Therefore, there a need to provide resilient and cost-effective materials, such as limestone calcined clay cement (LC3). However, exploitation LC3 limited due lack mineralogical information about clays related strength durability when used cementitious material. In this study, physico-chemical properties systems 50% 40% clinker contents...

Sustainable building should at least be affordable and carbon neutral. Sub-Saharan Africa (SSA) is a region struggling with housing affordability. Residential buildings are often constructed using block-based materials. These increasingly produced ordinary Portland cement (PC), which has high footprint. Using alternative Supplementary Cementitious Materials (SCMs) for block production might reduce the footprint price. The purpose to assess level of information SCM use in blocks SSA this...

Chloride-laden environments pose serious durability concerns in cement based materials. This paper presents the findings of chloride ingress chemically activated calcined Clay-Ordinary Portland Cement blended mortars. Results are also presented for compressive strength development and porosity tests. Sampled clays were incinerated at a temperature 800°C 4 hours. The resultant clay was with Ordinary (OPC) replacement level 35% by mass OPC to make test labeled PCC35. Mortar prisms measuring 40...

Prediction of strength in cement based materials is vital construction industry as it forms the basis upon which important tasks can be performed such time for mortar form removal, project scheduling and quality control among others.The paper reports both experimental simulated findings on compressive laboratory prepared blended mortars.The was by blending calcined clays with Ordinary Portland Cement (OPC) at replacement levels ranging from 35% to 50% mass OPC.In approach, mortars measuring...

Though the technical knowledge to make cement and concrete more sustainable already exists, implementation of solutions lags behind rate needed mitigate climate change meet targets set by Sustainable Development Goals. Whilst most focus around built environment is on embodied carbon, we stress an important but neglected dimension: partnership (SDG17). Effective partnerships can be powerful enablers accelerate in concrete, let such transfer from academia market. This achieved through...

This paper presents the findings of an experimental investigation on optimizing pozzolanic activity a blend Rice Husks (RH), Spent Bleaching Earth (SBE) and Broken Bricks (BB) to form pozzolana that would have comparable natural pozzolanas. Four ratios RH, BB, SBE were burnt in Fixed Bed Kiln (FBK). The starting ratio had 20 kg 0 BB 4 SBE. amount was increased by 2 each maximum 6 as mass kept constant. resultant ashes subjected various tests. included; saturated lime test compressive...

This paper reports leach and/or intake of SO 4 2− , Cl − Ca 2+ Na + and K from into cement mortar cubes made a novel cementious material in naturally encountered environmental simulated media. The also changes pH the media over time exposure to cubes. compressive strength test are reported. cement, labelled PCDC, intermixing ordinary Portland (OPC) with waste materials which included rice husks, bricks, acetylene lime sludge, spent bleaching earth was previously tested found meet Kenyan...

Cement structures are major capital investments globally. However, exposure of cement‐based materials to aggressive media such as chloride‐ and sulphate‐laden environments coastal areas affects their performance. Ordinary Portland cement (OPC) is the main used in buildings civil dams bridges. This paper reports findings an experimental investigation on effect ingress Cl − SO 4 2− compressive strength development ions’ diffusivity selected OPC brands Kenya. The included seawater (SW)...

The paper presents experimental findings on the performance of Limestone Calcined Clay Cement (LC3) in acidic media. LC3 was made by inter-grinding a blend 50 % clinker with ground 30 Fired Rejected Bricks (FRCB), 15 limestone and 5 gypsum. Compressive strength water absorptivity mortars were investigated vis-à-vis commercial Ordinary Portland (OPC) Pozzolana (PPC). Microstructural analysis hydrated samples conducted using Scanning Electron Microscope (SEM) before after immersion 3% H2SO4....

In the presence of significant quantities carbon dioxide (CO2) and elevated temperatures in atmosphere due to climate change, cement-based materials are susceptible carbonation. Blended cements more prone carbonation attack than Portland cement. There is a need evaluate resistance blended carbonation-prone environment. This paper presents experimental findings obtained from an evaluation tests on Rice Husk Ash- (RHA-) The cement was made by intergrinding Cement (PC) RHA make test (PC-RHA)....

The durability of cement-based structures majorly depends on their resistivity to the aggressive media in construction environment. most ions commonly encountered environment are chloride (Cl − ) and sulphate (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mrow><mml:msubsup><mml:mrow><mml:mtext>SO</mml:mtext></mml:mrow><mml:mrow><mml:mn>4</mml:mn></mml:mrow><mml:mrow><mml:mn>2</mml:mn><mml:mo>−</mml:mo></mml:mrow></mml:msubsup></mml:mrow></mml:math>). interactions...

Conventional binders in the particleboards formulation involve use of formaldehyde resins. Epidemiologic studies show that is carcinogenic. Efforts to reduce emissions by scavengers has not been proven emission. Molecular bonding biobased adhesive molecules with lignocellulose materials provides an alternative way producing composite material. In this study, maize stalk (MS), rice husks (RH) and sugarcane bagasse (SB) were used as sources for particleboard formulation. SB, MS RH collected...