ÖZETBu çalışmada Erzurum ovasından alman 40 toprak örneğinin kıvamlimitleri (aşağı plastik /imi/, yukarı plastik limit ve plastiklik indiksi)ve sıkışma parametreleri (maksimum kuru densite ve optimum nem)ve ilaveten maksimum kuru densiteye tekabül eden toplam porozite ilebazı toprak özellikleri (kil, silt, kum, organik madde ve kireç miktarı)arasındaki ili§kileri incelenmiş ve topraklarm iş/enmeye uygunluk vesıkışaMiirlik bakımından değerlendirilmesi yapılmıştır.Casagrande plastiklik diyagramına göre, topraklarm % 25'i az,%65'i orta ve %lO'u yüksek derecede plastikfiğe sahip bulunmuştur.Topraklar sıkışabilirlik yönünden kullanılan sıkıştırma lesti ile eldeedilen maksimum kuru densite < 1,5 gfcm 3 olduğunda "düşük", 1-5-1,7gfcm3 arasında olduğunda "orta" ve > 1,7 glcm 3 olduğunda ise "yüksek"olarak sınıflandırılmışlardır. Buna göre, toprakların % IO'u düşük,! % 68'; orta ve %21!si yüksek derecede sıkışçbilirliğe sahip bulunmuşlardır.SUMMARYA STUDY ON THE CONSISTENCY LIMITS AND COMPACTIBlLITYOF THE SOILS OF ERZURUM PLAINThis study was ':done with thepurpose to work out the relationships'.between 'the consistency limits (lowerplastic limit, upper lastic limit andplasticity index) and some sotı pmperties(Cıay, sih, sand, organic matter,and lime content), and betweenthe compaction parameters ,(maximumd!)' density, optimum moisture andadditionaUy total poroşity at the maximumdry density) and the same soilı;ıroperties and to evaluate the soit inthe proper conditions for tillage 'andin 'compactibility, using soil samplestaken frem the Erzurum pJain in easternTurkey.it was found that there are bighlysignificant positive relationships betweenthe three' plastic lirnits and cJ~ycontent, and highly sıgnificant negativerelationships between the threeplastic limits and sand content. Siltcontent showed a positive relationshipsignificant at the 5% level with lowerplastic limit, and nonsignificant relationshipswith upper plasticIimit and_ with plasticity index, Lime content gavepositive reJationships significant atthe 1 % JeveJ with·' lower plastic hmitand at the 5 %JeveJ with upper plastic. limit, and a nonsignificant reJationshipwith pJasticity index. . /According to the Casagrande pJasticitychart, it was foqnd that 25 %of the soiJs have "law_", 65 % of thesoİls have "medium'" and LO % ofthe soils have "high', plastieity. it wasevaIuated in the following ways; Highplasticity means that the possibility of 'tilIing the soil when it is wet and thedanger for the soil structure is highand the soil should be tilled when friabIe.Medium plasticity means that thepossibility of tilling the soil when it iswet and the danger for the strueture ismoderate and it wiU be b~neficial tocare in tilling the soil when friable.Low plasticity means that it will be ratbereasy to catch the soil in rriablecondition for tilling.it was found that there are highlysignificant negative reIatiQnship~ betweenmaximum dry density of thes.oils ad day cantent, between maximumdry density and organic mattercontent, and' between maximum drydensity and Iime content. MaximufD. drydensity showed a highly significantpositive re1ationship with sand cantent,and a nonsignificant reIalionship withsilt content.on the other hand; optimum moisturecontent gave highly significahtpositive reIationşhips with day content,with organic matter content, andwith lime content; a highliy significantnegative relationship with sand content;and a nonsignificant relationship wjthsilt content..AdditionaUy, total pomsity at themaximum dry density' showed highlysignificant positive relationships withclay content, and with otrganic mattercontent a highly significant negativerelationshisp with sand content; andrelationships significant at the 5 %level with silt content, and ,w.ith limecontent.The soiJs, were classified in com·pactibility as "lo\Y" when the maxi·mum dry density obtained with tbecumpaction test used, is < 1.5 g/cm3,as "medium" with maximum dry densitiesbetween 1.5-1.7 g/cm3; and "high"when the maximum dry density is >1.7 g/cm3.According to this Cıassification, itwas found that iO%of the soils havelow compactiility, 68 % of the soilshave medium compactibility, and 22%of the soils have high compactibility.