Evaluation of flexural-tensile strength of high-performance soil-cement (HPSC) specimen bodies

Abstract

Current studies indicate that it is possible to obtain soil-cement products with similar performances to high performance concrete (HPC). In this context, this work aimed to evaluate the flexural rupture parameters of high-performance soil-cement specimens (HPSC) in relation to the cement percentage. Eighteen HPSC specimens were analyzed, produced with compaction moisture of 13% and pressure of 1.2 MPa. The average flexural-tensile strength of the specimens was 4.6 MPa with 30% cement, 5.6 MPa with 40% cement and 5.8 MPa with 50% cement. The results indicate the possibility of using a new product (HPSC) with flexural-tensile strength equivalent to HPC, but without the need to use mining materials, such as sand, gravel and other additives like superplasticizers. This opens up the opportunity to produce new soil-cement artifacts, such as plates and/or floors, for which values of flexural-tensile strength higher than those currently obtained in concrete and/or soil-cement products are required.

Flexural Strength of High-Performance Soil-Cement: A New, Alternative, Sustainable Construction Material

“…It can be observed that, in general, the flexural strength values obtained at 28 days were always below 2.5 MPa. The only flexural strengths that exceeded 2.5 MPa were reported in the study by Rocha et al [23], achieving 5.8 MPa at 120 days, and those of Namboonruang et al [46,47], who obtained values <5.5 MPa at 28 days, albeit using a very high cement percentage (up to 50%). Therefore, even when using a high percentage of cement, the flexural strength values remained below 6 MPa at 28 days.…”

“…In most of the soil-cement studies found, the cement percentage values are below 13%. Only in the studies by Rocha et al [23], Namboonruang [46,47], and Ademati et al [48] were higher cement percentages used. It can be observed that, in general, the flexural strength values obtained at 28 days were always below 2.5 MPa.…”

“…In a search on Google Scholar for the term "high performance concrete", 141,000 results were found. However, there is little published work on high-performance soil-cement (HPSC), with only three studies [17,22,23] being found in the literature when searching for "high performance soil-cement". In the study by Duong et al [22], this type of material refers to the soil-cement used to improve the soil conditions for paving and/or improve the settlement of foundations and not for the production of construction pieces.…”

“…The study by Carvalho et al [17] defines which production parameters should be improved to obtain a soil-cement with performance characteristics similar to an HPC. The study by Rocha et al [23] produced HPSC pieces with 4.6 to 5.8 MPa of flexural strength using 30 to 50% cement in the mixture. Currently, no references have been found in the literature for soil-cement with a similar performance to that of HPC, that is, with compressive strengths reaching 50 MPa.…”

“…In this case, an increase in moisture (higher water content) would increase the compaction of the specimen and, consequently, its strength. Three studies directly described the values of compaction moisture as a percentage of the weight of the dried piece: Rocha et al [23], with values of 13% moisture when using 30, 40, and 50% cement; Sitton et al [41], with values of 11.4% moisture when using 10.9% cement; and Donkor et al [42], with values of 9% moisture when using 8% cement. The specific optimum compaction moisture cannot be determined as it varies depending on the compaction energy used.…”