IN-SITU TEST DEVICE TO DETERMINE LATERAL EARTH PRESSURE

LATERAL EARTH PRESSURE IS FUNDAMENTAL TO MUCH OF SOIL MECHANICS, AND VITAL TO THE SOLUTION OF MAY PRACTICAL PROBLEMS INCLUDING COMPUTERIZED SOLUTIONS FOR BEARING CAPACITIES AND FOR STABILITY OF TUNNELS, SLOPES AND WALLS. UNFORTUNATELY, THE KEY ROLE OF LATERAL STRESS HAS TENDED TO BE PASSED OVER IN ENGINEERING INVESTIGATIONS BECAUSE OF DIFFICULTIES IN ITS MEASUREMENT. ASSUMED VALUES OR VALUES BASED ON SOME VERY LOOSE EMPIRICAL CORRELATIONS FREQUENTLY ARE USED DESPITE AN ACKNOWLEDGED AND DEMONSTRABLE ERROR THAT USUALLY WILL RESULT IN OVERDESIGN. THE PROBLEMS IN MEASUREMENT FOR THE MOST PART DERIVE FROM THE SENSITIVITY OF SOIL STRESS TO INTRODUCTION OF A MEASURING DEVICE. THE SEVERAL APPROACHES TO THIS AND OTHER MEASUREMENT PROBLEMS WILL E ANALYZED AND EVALUATED, WITH SPECIAL ATTENTION TO PROBABLE EFFECTS ON SOIL BEHAVIOR AS IT PERTAINS TO ACCURACY AND RELIABILITY OF EACH TYPE OF TEST. AN EXISTING DATABASE OF KO STEPPED BLADE, DILATOMETER, AND PRESSUREMETER DATA WILL BE USED TO HELP SELECT ONE OR AT MOST TWO APPROACHES OR TEST PROCEDURES FOR FURTHER INVESTIGATION, IMPROVEMENT, AND USE DURING PAHSE II.