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Cement-Treated Base (CTB) is a non-conventional method used in road bases materials to improve its engineering properties due to the hardening of cement when moisture is present and extends the period of curing times. This study investigates the effects of cement additive on properties of base layer using laboratory mechanistic evaluation of stabilized soil mixtures. Laboratory tests conducted were Unconfined Compressive Strength (UCS), Indirect Tension test for Resilient Modulus (ITRM) and Flexure Strength (FS) tests. The results revealed that by adding Portland cement, the mechanical properties of the mixture have improved where the UCS is found to be an important quality indicator. In addition, the variables that influenced these tests, which are cement content, curing time, moisture content, and dry density, play important role to determine the performance of CTB. This paper presents the finding of a correlation conducted to analyse the influences of these variables using regression and ANOVA to establish significant models with the aim of predicting the strength base on mixture parameters. Keywords: Cement-Treated Base, Unconfined Compressive Strength, Indirect Tension test for Resilient Modulus, Flexure Strength, Moisture Content, Dry Density, Regression Analysis.

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This study examines the potential of the soft computing technique—namely, Gaussian process regression (GPR), to predict the ultimate bearing capacity (UBC) of cohesionless soils beneath shallow foundations. The inputs of the model are width of footing (B), depth of footing (D), footing geometry (L/B), unit weight of sand (γ), and internal friction angle (ϕ). The results of the present model were compared with those obtained by two theoretical approaches reported in the literature. The statistical evaluation of results shows that the presently applied paradigm is better than the theoretical approaches and is competing well for the prediction of UBC (qu). This study shows that the developed GPR is a robust model for the qu prediction of shallow foundations on cohesionless soil. Sensitivity analysis was also carried out to determine the effect of each input parameter.

Polymer modified bitumens have tended to be the most popular among the various types of modified binders that are available worldwide. Polymer modification significantly alters the rheological characteristics of the binder, thereby requiring the use of fundamental rheological testing methods to provide an indication of the performance of the binder and subsequently the asphalt mixture. In this paper the characterization of bitumen modified with epoxidized natural rubber (ENR) was done with four percentages of ENR content. The effects of the modifier on the conventional properties, storage stability and rheological properties were investigated. The results indicated that storage stability of ENR modified bitumens (ENRMB) were mainly dependent on the ENR content. ENR reduced the temperature susceptibility. The degree of the improvement generally increased with ENR content up to 9%.