TEST APPARATUS TO MEASURE SHEAR STRENGTH OF FOAM-MIXED SOIL FOR OPTIMAL FOAM MIXING DESIGN AND TEST METHOD THEREOF

摘要

The present invention relates to a test apparatus to measure the shear strength of foam-mixed soil for an optimal foam mixing design, capable of measuring the shear strength of the foam-mixed soil through a vane attached in a tunnel boring machine (TBM) chamber, and a test method thereof. According to the present invention, the test apparatus to measure the shear strength of foam-mixed soil for an optimal foam mixing design of a soil pressure type TBM comprises: a housing; a packing sample box disposed on the bottom of the housing, having an opened upper part, and storing packing soil therein; a soil chamber disposed on the upper side of the packing soil box in the housing, receiving soil by excavation of the soil stored in the packing sample box, having a soil outlet formed on one side to discharge the received soil, and including a vane shearing device to measure the torque of the inside; a small blade including a cutting tool coupled to the lower end of a rotary shaft, disposed on the bottom of the soil chamber, and excavating the soil stored in the packing sample box, and a foam injection hole to inject a foaming agent mixed by a set mixing ratio towards the soil; a servo motor driving the rotary shaft to rotate the small blade; a soil discharge unit disposed in the soil outlet to adjust the discharge soil amount of the discharged soil so as to adjust the internal pressure inside the soil chamber; a loading unit to move the small blade towards the soil to apply a vertical load to the soil side; a foam injection means to inject a foam with the set mixing ratio towards the foam injection hole; and a foam injection pipe installed between the foam injection means and the foam injection hole.;COPYRIGHT KIPO 2018