Geotechnical evaluation of lower miocene limestone at Jonggrangan area Kulonprogo District Yogyakarta Special Province Indonesia

MOHAMMED, Badri Edwin, Ir. Dwikorita Karnawati, M.Sc., Ph.D

2008 | Tesis | S2 Teknik Geologi

Limestone has worldwide attention because of their economic worth as building stone, concrete aggregate, road construction material , agriculture dressing, Portland cement manufacturing and as storage reservoirs for both petroleum and groundwater. At Jonggrangan area - Kulonprogo, Yogyakarta Province - Indonesia two kinds of limestone in some area occurrence and some age, which one having good geological characteristics and geotechnical properties and why?. To help solve that problem, this research is conducted to understand the geological conditions, engineering geological condition and to evaluate the geotechnical properties of limestone in such area. Based on the mineralogical and geochemical analyses, the occurrence of titanite in the limestone is supposed to be one of the main factors which have caused the limestone acquiring pink color. A correlation of the geotechnical results using the standard testing requirements. . The results of the aggregate impact value of the tested pink and white-grey limestone samples range between 16.56 % and 20.88 %. None of these values exceeds the maximum or the favorable limits issued by the British Standard for the use of limestone aggregate as pavement or concrete materials. The average unconfined compressive strength of the studied limestone varies from 8.876 MPa to 43.943 MPa. This range encompasses two classes of limestone to be used as a dimension stone according to the ASTM. Pink limestone samples are classified as class A. Meanwhile, white-grey limestone of the other samples are classified as class B. the studied limestone are considered to be strong (class III) pink limestone to moderately strong (class IV) white-grey limestone, while they are considered to be of medium strength (class C) to low strength (class D) according to Deer and Miller classification. In general, the studied limestone is classified as class I of a very high ultrasonic velocity according to the International Association of Engineering Geologist (IAEG) classification. It is recommended that the quality of the pink limestone classified as very high strength and good mechanical properties. Reserve estimation it’s huge. Although most be potentially useful for aggregate and constructions purposes since they satisfy a wide variety of specifications and uses, and must be of good quality.

Kata Kunci : Limestone,Economic worth,Petrographical examinations,Geochemical analysis,Geotechnical testing,White,grey and pink limestone