Estimation of Coefficient of Horizontal Subgrade Reaction by the Inverse Analysis on the Lateral Load Test Results

수평재하시험 역해석을 통한 수평지반반력계수 산정

  • 류수용 ((주)동호 지반공학부) ;
  • 곽노경 (서울시립대학교 토목공학과) ;
  • 박민철 (서울시립대학교 토목공학과) ;
  • 정상국 (송원대학교 토목공학과) ;
  • 이송 (서울시립대학교 토목공학과)
  • Published : 2012.08.01

Abstract

Even though decision of coefficient of horizontal subgrade reaction is important in analysis for pile under lateral load, the behavior of pile under lateral loading is estimated differently due to using established suggestion. Therefore this study estimates coefficient of horizontal subgrade reaction by using Chang's method or numerical inverse analysis method with the result of lateral load test. Then this study investigates the adequacy and reliability for coefficient of horizontal subgrade reaction. The analytical results of coefficient of horizontal subgrade reaction with lateral load test showed that coefficient of horizontal subgrade reaction with Chang's method was underestimated as compared with inverse analysis. Deformation modulus of foundation by Standard Specifications for Highway Bridges and Eo${\fallingdotseq}$1,400~1,600N showed similar range like range of coefficient of horizontal subgrade reaction with lateral load test.

수평하중을 받는 말뚝의 해석에서 수평지반반력계수($k_h$)의 결정이 중요하나 시간과 비용 등의 문제로 기존의 제안식을 이용하여 수평지반반력계수를 산정하고 있어 말뚝기초의 거동을 상이하게 평가하고 있다. 따라서, 본 연구에서는 수평재하시험결과를 이용한 Chang 방법 및 수치해석 역해석 방법으로 수평지반반력계수를 산정하여 기존 제안식과의 상관성을 비교 분석하여 적정성 및 신뢰성을 규명하였다. 수평재하시험에 의한 수평지반반력계수 분석결과는 Chang 방법으로 산정된 값이 역해석에 의한 방법에 비해 과소평가 되었다. 그리고 도로교 표준시방서 방법으로 산정 시 지반의 변형계수는 Eo${\fallingdotseq}$1,400~1,600N 적용하는 경우 수평재하시험에 의한 수평지반반력계수와 유사한 범위를 가지는 것으로 확인되었다.

Keywords

References

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