ERZURUM OVASI TOPRAKLARININ KIVAM LİMİTLERİ VE SIKIŞABİLİRLİĞİ ÜZERİNDE BİR ARAŞTIRMA

Abstract

OZET Bu calismada Erzurum ovasindan alman 40 toprak orneginin kivam limitleri (asagi plastik /imi/, yukari plastik limit ve plastiklik indiksi) ve sikisma parametreleri (maksimum kuru densite ve optimum nem) ve ilaveten maksimum kuru densiteye tekabul eden toplam porozite ile bazi toprak ozellikleri (kil, silt, kum, organik madde ve kirec miktari) arasindaki ili§kileri incelenmis ve topraklarm is/enmeye uygunluk ve sikisaMiirlik bakimindan degerlendirilmesi yapilmistir. Casagrande plastiklik diyagramina gore, topraklarm % 25'i az, %65'i orta ve %lO'u derecede plastikfige sahip bulunmustur. Topraklar sikisabilirlik yonunden kullanilan sikistirma lesti ile elde edilen maksimum kuru densite 1,7 glcm 3 oldugunda ise yuksek olarak siniflandirilmislardir. Buna gore, topraklarin % IO'u dusuk, ! % 68'; orta ve %21!si derecede sikiscbilirlige sahip bulunmuslardir. SUMMARY A STUDY ON THE CONSISTENCY LIMITS AND COMPACTIBlLITY OF THE SOILS OF ERZURUM PLAIN This study was ':done with the purpose to work out the relationships' .between 'the consistency limits (lower plastic limit, upper lastic limit and plasticity index) and some soti pmperties (Ciay, sih, sand, organic matter, and lime content), and between the compaction parameters ,(maximum d!)' density, optimum moisture and additionaUy total porosity at the maximum dry density) and the same soil i;iroperties and to evaluate the soit in the proper conditions for tillage 'and in 'compactibility, using soil samples taken frem the Erzurum pJain in eastern Turkey. it was found that there are bighly significant positive relationships between the three' plastic lirnits and cJ~y content, and highly significant negative relationships between the three plastic limits and sand content. Silt content showed a positive relationship significant at the 5% level with lower plastic limit, and nonsignificant relationships with upper plasticIimit and _ with plasticity index, Lime content gave positive reJationships significant at the 1 % JeveJ with·' lower plastic hmit and at the 5 %JeveJ with upper plastic . limit, and a nonsignificant reJationship with pJasticity index. . / According to the Casagrande pJasticity chart, it was foqnd that 25 % of the soiJs have law_, 65 % of the soIls have medium' and LO % ofthe soils have high', plastieity. it was evaIuated in the following ways; High plasticity means that the possibility of ' tilIing the soil when it is wet and the danger for the soil structure is high and the soil should be tilled when friabIe. Medium plasticity means that the possibility of tilling the soil when it is wet and the danger for the strueture is moderate and it wiU be b~neficial to care in tilling the soil when friable. Low plasticity means that it will be ratber easy to catch the soil in rriable condition for tilling. it was found that there are highly significant negative reIatiQnship~ between maximum dry density of the s.oils ad day cantent, between maximum dry density and organic matter content, and' between maximum dry density and Iime content. MaximufD. dry density showed a highly significant positive re1ationship with sand cantent, and a nonsignificant reIalionship with silt content. on the other hand; optimum moisture content gave highly significaht positive reIationships with day content, with organic matter content, and with lime content; a highliy significant negative relationship with sand content; and a nonsignificant relationship wjth silt content. .AdditionaUy, total pomsity at the maximum dry density' showed highly significant positive relationships with clay content, and with otrganic matter content a highly significant negative relationshisp with sand content; and relationships significant at the 5 % level with silt content, and ,w.ith lime content. The soiJs, were classified in com· pactibility as lo\Y when the maxi· mum dry density obtained with tbe cumpaction test used, is 1.7 g/cm3. According to this Ciassification, it was found that iO%of the soils have low compactiility, 68 % of the soils have medium compactibility, and 22 %of the soils have high compactibility.