Optimizing modified triaxial testing for small strain zone using local displacement transducers and bender element for cement-treated soft soil

¹ Kyushu University, Department of Civil and Structural Engineering, 744 Motooka, Nishi-Ku, Fukuoka, Japan
² Gadjah Mada University, Department of Civil and Environmental Engineering, 55281 Yogyakarta, Indonesia

^* Corresponding author: muhammad.akmal.putera@gmail.com

Abstract

The settlement behavior is a common problem on the railway structure that can be optimized by applying cement-treated soil as ground restoration. However, the application of a high cement mixing content needs a proper estimation that can be achieved by adjusting the element testing. The strain measurement devices can estimate the deformation characteristics, such as secant modulus, Poisson ratio, and shear modulus that can describe the settlement behavior and stiffness of cement-treated soil. This research is focused on a static analysis of triaxial consolidated undrained (CU^¯) testing that is improved by the axial and radial local displacement transducer (LDT) and bender element to increase the accuracy of measurement results. Furthermore, the secant modulus and shear modulus is more accurate when the combination of radial and axial LDT is used due to a small strain range. Lastly, the shear modulus measurement is improved by using a filler in the cement-treated soil for the bender element test. To conclude, this system of testing for the static condition can be utilized for the dynamic condition, because the measurement shows a reliable result for a small strain range which is the parameter of the dynamics condition.