Most soils in natural environments undergo wetting and drying cycles, without reaching full saturation. Therefore, it is essential to analyze their properties under unsaturated conditions. However, these analyses often require expensive equipment. This study proposes an empirical-experimental methodology to evaluate the elastic modulus and shear strength of unsaturated soils under total stress conditions using undisturbed and reconstituted samples of silty soil from Quito, Ecuador. Techniques for suction measurement, soil water characteristic curve (SWCC), and predictive models for shear strength and stiffness in partially saturated soils were reviewed. Unconfined compression tests were performed, and the SWCC was determined using the filter paper method. A three-dimensional (3D) plot was generated to correlate the matric suction, shear strength, and normal stress across varying suction levels. In the reconstituted samples, the shear strength and elastic modulus exhibited nonlinear increases in the low suction range (≤500 kPa). In the high-suction range, the strength declined beyond 2228 kPa (40.23% saturation), whereas the elastic modulus stabilized. Undisturbed samples displayed greater variability owing to their heterogeneity, macrostructure, and hysteresis. The results suggest that matric suction enhances the shear strength and stiffness of the surface layers, whereas a higher saturation at depth reduces these properties. This paper further discusses the limitations and practical applicability of the proposed methodology.

The present investigation determines the influence of abaca (Musa textilis) fiber inclusion on the simple compressive strength of reconstituted sandy silt specimens. For this purpose, fibers of different lengths (5, 10 and 15 mm) and quantities (0.5, 1.0, 1.5 and 2.0% of soil dry weight) are added to produce the reconstituted specimens. Subsequently, the physical and mechanical behavior of soil–fiber mixtures were evaluated through compaction and unconfined compression tests. The experimental results showed that increases in fiber content or length, or both, led to a 1235.1% increase in maximum compression stress (compared to the fiber-free soil). Compression failure occurred at a greater axial strain when 10 and 15 mm fibers were added at 1% dosage or in percentages equal to or greater than 1.5% regardless of fiber length. A series of linear mixed models identified statistically significant effects of fiber length and percentage on the level of effort and on the unitary deformation.

The quality control of concrete paving blocks in Ecuador has remained unchanged since 1987, using as a criterion of quality and durability the value of the compressive strength of the block under the concept of global indicator. This indicator assumes that when the axial load carrying capacity specification is met, it will cover requirements such as abrasion resistance, therefore the expectations of the paving surface design life. However, in recent years an early deterioration of the paving brick surfaces has been verified in general despite compliance with the axial load carrying capacity requirements established in the Ecuadorian standard. Under these conditions, the University, the construction industry and the Ecuadorian Standardization Institute (INEN) decided to adapt a new control standard in which the indicator of acceptance is broken down into several physical and mechanical parameters, using the European standard EN 1338 as a reference document. Among the parameters, the quantification and assessment of abrasion resistance became of greater interest, both because of the lack of abrasion resistance of most of the production in the country, as well as the test method to be used. The present article, based on a traditional statistical analysis of 516 abrasion resistance tests by means of the wide wheel abrasion test method (EN 1338) performed at the Construction Materials laboratory of the Pontifical Catholic University of Ecuador (PUCE) between 2010 and 2015, verified the symmetrical normal distribution behavior of the two lots in which the data were classified; one corresponding to plants that maintain quality control processes and another to plants without control in addition, quantified the characteristic tyre track value according to the abrasion test in the analysis period. Through the information obtained, the need for abrasion control has been justified, as well as the recommendation to establish a specification for Ecuador, different from that established in the European standard