Impact of Changing Microstructural Compositions of Lime Based Mortar on Flexibility: Case Study of Sustainable Lime-Cement Composites

Olaniyan, Sule Adeniyi

doi:10.25046/aj0506179

Cited by 2 publications

(4 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Details of the microstructural characteristics evaluation (in respect of the total porosity, median pore diameter, bulk density and pore size distribution, using Mercury Intrusion Porosimetry (MIP) technique via AutoPore IV 9500 by Micrometrics (with pressure range up to 60000 psi)), mechanical properties assessment (using ELE AutoTest 2000 apparatus and INSTRON 3367) and some other relevant preliminary material testing (involving 'Carl Zeiss EVO 50' Scanning Electron Microscope and Laser Difractometry Xmastersize) are as documented in the previous studies [4], [28] and [38].…”

Section: B Analytical Methodologymentioning

confidence: 99%

“…As shown in Table III, using the adopted B/A ratio (i.e., 1:3), mortars were prepared with increasing/decreasing cement contents. Mixing was done in the laboratory mixer of 30 litres maximum capacity as explained in previous studies [4], [28] and [38]. Three prismatic specimens of 40×40×160 mm was prepared for each mortar mix.…”

Section: A Materials and Mortar Preparationmentioning

confidence: 99%

“…Because of high waterretaining nature of lime, and its associated long carbonation process, the observed large pores arise from evaporation of excess unbound kneading water. The pores cannot be dissociated from fine cracks usually resulting from drying shrinkage which is capable of expanding and widening [4] [28]. Despite continuous carbonation at 6-months, wider pore range is prevalent, showing a presence of more pores with larger sizes (between 0.5 µm and 40 µm) (Fig.…”

Section: B Microstructural Featuresmentioning

confidence: 99%

“…It is obtained from mixing lime, sand and water together in a proportional ratio. It is a flexible and slow to harden material, thereby allowing minute movements within the mortar joints, without impacting negatively on the masonry's structural stability [1]- [4]. Its flexibility feature helps to cushion masonry joints, accommodate strains, inhibit cracking, thereby resulting in good flexural bond strengths [5], [6].…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Pore Structure as a Determinant of Flexibility in Sustainable Lime-Cement Mortar Composites

Olaniyan

2021

EJENG

Self Cite

View full text Add to dashboard Cite

Flexibility of Lime Mortar resulting from its good permeability feature through its relatively large interconnected pore structure makes it popular as an old sustainable building material. This characteristic feature enhances its capability to suppress masonry deformation. However, its mechanical strength is weak. To address this shortcoming, cement is added to form a stronger composite. This study, therefore, evaluates the pore structure of the resulting lime-cement composite, with a view to assessing impact and sustainability of the lime’s flexibility in the overall performance of the composite. Adopting equal mix ratio (1:3) of Binder/Aggregate (B/A), mortars were prepared using lime as a lone binder, as well as other five different compositions in the ascending and descending order of lime and cement binders (i.e., 1:1, 1:2, 1:3, 2:1 and 3:1). Each composition was assessed in fresh state using Water/Binder ratio, Air Content and Bulk Density. For the hardened state assessments, mechanical characteristics and microstructural features evaluated through six (6) and twelve (12) month curing periods respectively, were considered. Results of the investigation reveal that low cumulative porosity (i.e., summation of the porosities) across the three pore regions of Inter-Nano pores (1 – 10 nm), Super-Nano pores (10 – 100 nm) and Sub-Micro pores (0.1 – 1 µm), for each of the mortars, is observed to be synonymous with low cement content, low Modulus of Elasticity, low (fc/ff), and thus, high flexibility. This observation is supported by high linear coefficient of correlation (R2 = 0.89) for the equation describing both ‘cumulative porosity’ (within the referenced three pore ranges) and cement content. Thus, it could be inferred that despite cement addition with resulting alteration in the pore structure of the composite, presence of lime would retain flexibility property of the composites, with more flexibility in the descending order of cement contents. Considering the impacts of pandemic climate change, growing energy costs and human activities on the environment, this study therefore attempts to promote revival of an old but partially abandoned sustainable lime based mortars, with a view to facilitating improved lime mortar performances, conservation of energy resources and overall protection of the environment.

show abstract

Section: B Analytical Methodologymentioning

confidence: 99%

Section: A Materials and Mortar Preparationmentioning

confidence: 99%

Section: B Microstructural Featuresmentioning

confidence: 99%