Sample preparation method for large scale shear testing of soft-clay and granular-column composites.

This article is aimed at giving an overview of the testing equipment and sample preparation techniques for large scale shear testing of granular column enhanced soft clays. A novel testing device, designated Unit Cell Shear Device, is produced to enable clay bed consolidation and subsequent granular column installation within the clay bed. The device allows for studying the shear resistance of unit cells enhanced with slender vertical inclusions such as stone columns, geosynthetic encased stone columns, grouted piles, and conventional piles. The present study illustrates the novel clay slurry consolidation method, sample preparation sequence, testing device features, and the details of the actuators that shear the specimen. The strength parameters of the consolidated clay and the spatial distribution of engineering properties of clay are studied with different testing methods. The techniques prescribed herein present a viable method of clay bed preparation for laboratory testing purposes with the following advantages: • Homogeneous clay beds for testing • Reduced drainage path and accelerated consolidation time • Consolidation around a vertical inclusion to allow for column placement.

[Evaluation of bone mineral density, osteoporosis prevalence and regional risk factors in Turkish women living in Kastamonu: KASTÜRKOS study]. / Kastamonu'da yasayan Türk kadinlarinda kemik mineral yogunlugu, osteoporoz yayginligi ve bölgesel risk faktörlerinin degerlendirilmesi: KASTÜRKOS çalismasi

OBJECTIVES: This study aims to identify the bone mineral density (BMD) values and the prevalence of osteoporosis (OP) in Turkish women living in Kastamonu within the purpose of contributing to Turkish database and to explore whether the characteristics of the regional climate and demographics in different provinces of Turkey are risk factors, comparing our results with similar studies. PATIENTS AND METHODS: Between January 2009 and December 2011, 778 of 2018 subjects who were admitted to the healthcare centers equipped with dual energy X-ray absorptiometry (DXA) device in Kastamonu and met the inclusion criteria were included. The results of BMD were compared with the studies performed by Lunar DXA in two different provinces. The mean regional data obtained from the Turkish State Meteorological Service (1975-2010) and Turkish Statistical Institute (2009-2011) were used in the comparison of climate and demographic characteristics. The prevalence of OP was compared with those obtained from the FRACTURK study. RESULTS: The mean vertebral and femoral BMD values in all cases were lower than the values recorded in two geographical regions (Elazig-Istanbul), indicating a statistically significant difference (p<0.05). The mean temperature and duration of sunbathing in Kastamonu remained significantly lower than these two provinces for many years (p<0.05). The women population at the age of >50 and the old age dependency ratio were significantly higher in Kastamonu, compared to these provinces (p<0.05). The mean femoral BMD values of these cases >50 were significantly lower, suggesting a significant difference compared to the results obtained from FRACTURK study. The prevalence of OP (19.6%) was significantly higher than the FRACTURK study (p<0.05). CONCLUSION: The results of the KASTÜRKOS study indicate that the mean BMD values of Turkish women living in Kastamonu are lower and the prevalence of OP is higher than the values of the women living in different provinces.

Laboratory and field testing for utilization of an excavated soil as landfill liner material.

This study investigates the feasibility of using a silty soil excavated in highway construction as landfill liner material. The tests were conducted both at laboratory and in situ scales, and the soil was tested in pure and lime treated forms. Different levels of compaction energy were used. For the field study, a test pad was constructed and in situ hydraulic conductivity experiments were conducted by sealed double ring infiltrometers (SDRI). Laboratory testing revealed that while lime treatment improved the shear strength, it resulted in higher hydraulic conductivity values compared to pure soil. It was observed that leachate permeation did not change the hydraulic conductivity of the pure and lime treated samples. Laboratory hydraulic conductivities were on the order of 10(-9) m/s and met the 1.0E-08 m/s criterion in the Turkish regulations, which is one order of magnitude higher than the value allowed in most developed countries. SDRI testing, which lasted for 6 mo, indicated that lime treatment increased the hydraulic conductivity of pure soil significantly in the field scale tests. In situ hydraulic conductivities were on the order of 1E-08 and 1E-07 m/s, and exceeded the allowable value in the Turkish regulations. Undisturbed samples collected from the test pad were not representative of field hydraulic conductivities. Contrary to laboratory findings, higher compaction efforts did not result in lower hydraulic conductivities in field scales. The study verified the importance of in situ hydraulic conductivity testing in compacted liners.