Caracterização geotécnicas do solo da praia de Zalala

Abstract

The present work aims to study the geotechnical characteristics of the Zalala beach, with more emphasis on the following geotechnical parameters: i) resistance to penetration; (ii) texture, and (iii) soil moisture content, where Zalala soil load capacity was estimated from the first parameter without soil deformation; from the texture was made the textural classification of the soil and analysis of the parameters of the granulometric distribution (coefficient of uniformity and coefficient of curvature); and the third parameter was the water classification of the soil. The accomplishment of this work comprised four main phases: literature review, in situ tests, laboratory tests and processing of the results. Three field campaigns were carried out; in the first two, two profiles were obtained, where the first one was 1.8 m depth (PA) with 6 samples and the second was 2.1 m (PB) with 7 samples, the samples were divided in each 30cm deep, and the last campaign consisted of the creation of an instrument similar to that of SPT to determine the soil penetration resistance index. Two laboratory tests were carried out, the determination of the moisture content and particle size analysis. The granulometric analysis consisted in the first elimination of the impurities, such as the carbonates and the organic matter in the samples, so that these impurities did not influence in the granulometric tests. It was observed that the superficial layers of the Zalala beach range from compact to medium-compact, corresponding to a permissible tension range of 1 to 4 kg / cm2; and the texture showed that the size of the grains increased gradually as a function of the first 2.1m of depth, being classified as sandy soil with very fine sand in the superficial layers and fine sand in the bottom layers, and it was also verified that in relation to the uniformity coefficient the soil is classified as uniform soil and in relation to the coefficient of curvature is classified as poorly graded soil; and in relation to moisture it was verified that the soil of the beach of Zalala varies between soil with low humidity (in PA) and soil of a medium moisture rate (in PB). The obtained results allowed to conclude that the penetration resistance index reveals that the coast of the beach of Zalala does not have capacities to withstand tension greater than 4 kg / m2; and the fact that the soil is uniform and poorly graded gives it poor quality in order to be implanted with certain infrastructures on it, because these soil properties weaken the intermixing between the constituent grains of the soil and, on the other hand, the fact of the soil to vary from soil to an average soil moisture rate with a lower humidity rate, gives it a good quality to be implemented infrastructures.