The Geo-Hydro-Mechanical Properties of a Turbiditic Formation as Internal Factors of Slope Failure Processes

Similar to many inner areas of Southern Europe, the Daunia Apennines are affected by widespread landsliding, often consisting of slow, deep-seated movements. Recurrent acceleration of these landslides causes damage to buildings and infrastructures, severely biasing the socio-economic development of the region. Most landslides in the area of study occur within clayey units of turbiditic flysch formations, often severely disturbed by tectonic thrust and previous landsliding. The Faeto Flysch (FAE) is one of the most widespread turbiditic formations in the Daunia Apennines and is representative of the tectonised geological formations involved in slope failure. This work, by examining the landslide processes occurring at four pilot sites, aims at connecting the observed mechanisms to the geo-hydro-mechanical setup of FAE in the slopes. It is found that the soil portion of FAE consists of highly plastic clays, resulting in low intrinsic shear strength, and hence controls the initiation and progression of failure in the slopes, as such representing an internal predisposing factor to landsliding. In addition, the presence of fractured rock strata confers a high permeability at the slope scale, with respect to that of the soil matrix. This results in severe piezometric levels in the slope, which represent another internal predisposing factor to failure, and in the ability to induce significant seasonal pore water pressure oscillations down to great depths, connected to rainfall infiltration, thus triggering the recurrent acceleration of the landslides.

Geochemical trends in weathering profiles and their underlying Precambrian basement rocks in Akure, Southwestern Nigeria

Akure area in southwestern Nigeria falls within the basement complex underlain by migmatite, quartzite granite and charnockite. Geochemical features of these crystalline rocks and their overlying in-situ weathering profiles are investigated and reported. Analytical result from ICP-MS facility at the University of Malaya reveals average SiO2 content in quartzite (91.1%), granite (73.8%), migmatite (67.4%) and charnockite (58.6%) categorize the rocks as siliceous. SiO2 contents in the weathering profiles above these rocks are 61.9%, 60.2%, 52.2% and 54.6% respectively. Alumina contents in the weathering profiles overlying quartzite (23.8%), granite (19.9%), migmatite (26.3%) and charnockite (24.3%) are substantially higher than the precursor rocks. In the same order, average alkali (Na2O+K2O) contents in the profiles are 3.38%, 3.42%, 3.48% and 2.68%. Chemical features of the profiles reflect that there exists some correlation between the chemistry of crystalline basement and their in-situ weathering profiles. The residual soils contain low plastic clays with kaolinitic characteristics and compare well with other clays reported from other parts of Nigeria basement complex.

Availability of raw materials in the state of Piauí for the production of ceramic coating

The main raw material for the production of ceramic materials is clay, it can be found in large quantities throughout Brazil, in addition to having a simple processing method in the preparation of the mass of ceramic tiles using mixtures of kaolinitic clays (not very plastic) and illitic (plastic) clays, this mixture favors by developing a series of functions such as: light-burning color; act as binders and plasticizers; facilitate fluidity, due to its melting properties, provide a good burning density and excellent mechanical resistance. This work addresses the main basic white-burning raw materials used in the production of ceramic tiles: quartz, kaolin, talc and limestone and their influence on the ceramic mass. All raw materials mentioned are available in the State of Piauí. For this, a bibliographic review of a descriptive, basic and qualitative nature was carried out on the theme and with the results, it was possible to identify the existence of white-burning raw materials in the State of Piauí that can be used in the production of ceramic coating.

How Soils Can Help Predict High Rebound of Prestressed Concrete Displacement Piles

Excessive pile rebound has been occurring for over a decade, when high displacement pre-stressed concrete piles are driven mostly with single acting diesel hammers in Florida’s low permeability very fine sand blends. This very complex engineering phenomenon, which occurs due to interactions be-tween the soil, pile, and hammer; typically is observed at depths great than approximately 15 m (50 feet). Rebound greatly diminishes the end bearing capacities, causing various problems and significant cost increases. Findings from several research studies have produced some obvious trends based on grain size, Atterberg limits and cyclic triaxial testing. Excessive rebound was categorized as movements exceed-ing 12.5 mm (0.5-inches) while no-rebound was considered to be less than 6 mm (0.25-inches). Coarse grained rebound soils were very fine sands, passing the number 100 sieve, with silts and clays. According to the Unified Soils Classification System they classified as SM and have silt contents between about 20 and 40%. Cohesive rebound soils were highly plastic clays, classified as CH and also have silt contents between about 20 and 40%. Cyclic triaxial testing indicated that rebound soils are much more resilient than no-rebound soils, requiring many more cycles to produce strains of 2.5, 5, 10 and 15 percent.

THE CERAMICS OF TOMSK LOCAL OPTION KULAI CULTURAL-HISTORICAL COMMUNITY (ACCORDING TO THE SETTLEMENTS KIZHIROVO II AND SHELOMOK III)

В статье представлены результаты исследований керамики двух поселений локального варианта кулайской культурно-исторической общности из Томского Приобья. Первый памятник отражает появление в Томском Приобье населения кулайской культуры и его взаимодействие с автохтонным населением шеломокской (кижировской) культуры, в результате которого формируется томский локальный вариант кулайской КИО. Второй относится к заключительному этапу ее существования в Томском Приобье. Основная задача технико-технологического анализа заключалась в выявлении специфики культурных традиций в отборе исходного сырья и подготовке формовочных масс и сравнительном анализе полученных результатов. В результате исследований установлено, что гончары с Кижирово II предпочитали слабоожелезненные и неожелезненные пластичные глины, использовали несколько источников исходного сырья, отмечена устойчивая традиция в выборе минеральных примесей (добавление дробленого камня). Зафиксировано смешение культурных традиций и взаимодействие населения. Одной из причин наличия сосудов из других по ожелезненности глин может быть связано с новым населением на памятнике. К основным культурным традициям на Шеломке III относится использование пластичной среднеожелезненной глины и добавление дресвы. Отмечено смешение культурных традиций: местных (добавление дробленого камня) с принесенной (добавление шамота). Сравнительный анализ выявил общее и различное для керамики Кижирово II и Шеломок III. Общее — использование пластичных глин, преобладание традиции добавлять в формовочные массы дробленый камень, наличие контактов с населением с навыками, сложившимися в местности, где не были доступны выходы камня. Отличие керамики с Шеломка III от других памятников Томского Приобья в других навыках в выборе сырья – применении среднеожелезненных глин, не характерных для региона. Керамика из Шеломка III отличается и от керамики с памятников, расположенных рядом. Для поселения Кижирово II характерны те же традиции, что и с других памятников Томского Приобья. The article presents the results of research on the ceramics of two settlements of a local variant of the kulai cultural and historical community from the Tomsk Ob region. The first monument reflects the appearance in Tomsk Ob region population kulai culture and its interaction with the indigenous population shelomok (kizhirovo) culture, which is formed in Tomsk local option kulai KIO. The second relates to the final stage of its existence in the Tomsk Ob region. The main task of technical and technological analysis was to identify the specifics of cultural traditions in the selection of raw materials and the preparation of pottery paste and a comparative analysis of the results obtained. As a result of research, it was found that the potters from Kizhirovo II preferred weak ferruginous and non iron raw plastic clay, used several sources of raw materials, and noted a stable tradition in the selection of mineral impurities (the addition of crushed stone). There is a mix of cultural traditions and interaction of the population. One of the reasons for the presence of vessels from other clays may be due to the new population on the monument. The main cultural traditions on Shelomok III include the use of plastic medium- iron clay and the crushed stone. There is a mix of cultural traditions: local (adding crushed stone) with brought (adding chamotte). Comparative analysis revealed common and different of Kizhirovo II and Shelomok III ceramics. General — the use of plastic clays, the predominance of the tradition of adding crushed stone to the pottery paste, the presence of contacts with the population with skills developed in areas where stone outputs were not available. The difference between ceramics from Shelomok III and other monuments of the Tomsk Ob region is in other skills in the choice of raw materials — the use of medium ferruginous clays that are not typical for the region. The pottery from Shelomok III differs from the ceramics from the monuments located nearby. For settlement Kizhirovo II are characterized by the same tradition, as with other monuments in Tomsk Ob river area.