STUDI PERBANDINGAN KUAT TARIK UNIAKSIAL LANGSUNG DAN TIDAK LANGSUNG BATU GAMPING

• Main Author: Heriyadi, Bambang
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/1486
• Institution: Institut Teknologi Bandung

The tensile strength of rock is an essential parameter of rock mass characteristics and of importance in considering roof stability in underground mining and tunnelling. The tensile strength of rock is generally obtained from the indirect tensile test and this is due to its simplicity in preparing the specimen and testing method as well as its reliability. The research perpormed in order to know the comparisons of tensile strength value obtained from indirect tensile test through the Brazilian test with direct tensile test for Citatah limestone samples and moldy andesits from Mount Jaha. Before doing the testing, it\'s prepared priorly the design of direct tensile strength instruments. In establishing the geometry form of direct tensile test, it\'s studied the numerical modeling by using the Rheo-staub program package againts the model of test samples form : cylinder, dog-bone linier, dog-bone semi cyrcle and dog-bone cyrcle. According to the modeling results, it\'s selected the cylinder and dog bone cyrcle forms in order to make them as the test samples of direct tensile strength, with pulled by the end-full loading method by using the epoxy type adhesive glue, that has tensile strength 8.6 MPa. The findings of researc indicate that the value of direct tensile strength of limestone is more than value of Brazilian test, i.e., type A limestone has more value of direct tensile strength 1.2 times of Brazilian tensile strength value (4.54 MPa > 3.79 MPa). And for type B limestone, it has more value of direct tensile strength 1.4 times or Brazilian tensile strength value (8.13 MPa > 5.92 MPa). Whereas for moldy andesits, it\'s found the contrary results. The direct tensile strength less 0.75 times than Brazilian tensile strength value (2.81 MPa < 3.73 MPa). This matter caused by the availability of great considerable porocity on moldy andesit, i.e. 16.37 % ; whereas the porocity of typr A limestone is 7.98 %, and the porocity of type B limestone is 0.85 %. In addition, it\'s found also the evidence that value of direct tensile strength of dog-bone limestone test sample is more than value of direct tensile strength of cylinder form limestone. The value of direct tensile strength type A dog-bone limestone is more than 1.1 times of cylinder form (4.69 MPa > 4.38 MPa), and type B dog-bone limestone is 1.6 times of cylinder form (9.11 MPa > 5.87 MPa). And according to the interrelationships of stress-strain curves, it could be obtained the different form of curves for stress-strain tensile strength and uniaxial compression strength.