• 제목/요약/키워드: compressive and tensile strength prediction

검색결과 75건 처리시간 0.025초

콘크리트의 재료역학적 성질에 대한 양생온도와 재령의 효과(II) -예측 모델식을 중심으로- (Effect of Curing Temperature and Aging on the Mechanical Properties of Concrete (II) -Evaluation of Prediction Models-)

  • 한상훈;김진근;양은익
    • 콘크리트학회논문집
    • /
    • 제12권6호
    • /
    • pp.35-42
    • /
    • 2000
  • In paper I, the relationships between compressive strength and splitting tensile strength or modulus of elasticity were proposed. In this paper, new prediction model is investigated from estimating splitting tensile strength and modulus of elasticity with curing temperature and aging without compressive strength. New prediction model is based on the model which was proposed to predict compressive strength, and splitting tensile strength and modulus of elasticity calculated by this model are compared with experimental values of paper I. To evaluate in-situ applicability of the model, strength and modulus of elasticity tested with variable temperatures are estimated by the prediction model. The prediction model reasonably estimates the strength and the modulus of elasticity of type I and V cement concretes tested in paper I and experimental results with variable temperature tested in this paper.

새로운 겉보기 활성에너지 함수에 의한 콘크리트의 재료역학적 성질의 예측 (Prediction of Mechanical Properties of Concrete by a New Apparent Activation Energy Function)

  • 한상훈;김진근
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 2000년도 가을 학술발표회논문집(I)
    • /
    • pp.173-178
    • /
    • 2000
  • New prediction model is investigated estimating splitting tensile strength and modulus of elasticity with curing temperature and aging. New prediction model is based on the model which was proposed to predict compressive strength, and splitting tensile strength and modulus of elasticity calculated by this model are compared with experimental values. New prediction model well estimated splittinge tensile strength and elastic modulus as well as compressive strength.

  • PDF

Prediction model for the hydration properties of concrete

  • Chu, Inyeop;Amin, Muhammad Nasir;Kim, Jin-Keun
    • Computers and Concrete
    • /
    • 제12권4호
    • /
    • pp.377-392
    • /
    • 2013
  • This paper investigates prediction models estimating the hydration properties of concrete, such as the compressive strength, the splitting tensile strength, the elastic modulus,and the autogenous shrinkage. A prediction model is suggested on the basis of an equation that is formulated to predict the compressive strength. Based on the assumption that the apparent activation energy is a characteristic property of concrete, a prediction model for the compressive strength is applied to hydration-related properties. The hydration properties predicted by the model are compared with experimental results, and it is concluded that the prediction model properly estimates the splitting tensile strength, elastic modulus, and autogenous shrinkage as well as the compressive strength of concrete.

Clustering-based identification for the prediction of splitting tensile strength of concrete

  • Tutmez, Bulent
    • Computers and Concrete
    • /
    • 제6권2호
    • /
    • pp.155-165
    • /
    • 2009
  • Splitting tensile strength (STS) of high-performance concrete (HPC) is one of the important mechanical properties for structural design. This property is related to compressive strength (CS), water/binder (W/B) ratio and concrete age. This paper presents a clustering-based fuzzy model for the prediction of STS based on the CS and (W/B) at a fixed age (28 days). The data driven fuzzy model consists of three main steps: fuzzy clustering, inference system, and prediction. The system can be analyzed directly by the model from measured data. The performance evaluations showed that the fuzzy model is more accurate than the other prediction models concerned.

Prediction of unconfined compressive and Brazilian tensile strength of fiber reinforced cement stabilized fly ash mixes using multiple linear regression and artificial neural network

  • Chore, H.S.;Magar, R.B.
    • Advances in Computational Design
    • /
    • 제2권3호
    • /
    • pp.225-240
    • /
    • 2017
  • This paper presents the application of multiple linear regression (MLR) and artificial neural network (ANN) techniques for developing the models to predict the unconfined compressive strength (UCS) and Brazilian tensile strength (BTS) of the fiber reinforced cement stabilized fly ash mixes. UCS and BTS is a highly nonlinear function of its constituents, thereby, making its modeling and prediction a difficult task. To establish relationship between the independent and dependent variables, a computational technique like ANN is employed which provides an efficient and easy approach to model the complex and nonlinear relationship. The data generated in the laboratory through systematic experimental programme for evaluating UCS and BTS of fiber reinforced cement fly ash mixes with respect to 7, 14 and 28 days' curing is used for development of the MLR and ANN model. The data used in the models is arranged in the format of four input parameters that cover the contents of cement and fibers along with maximum dry density (MDD) and optimum moisture contents (OMC), respectively and one dependent variable as unconfined compressive as well as Brazilian tensile strength. ANN models are trained and tested for various combinations of input and output data sets. Performance of networks is checked with the statistical error criteria of correlation coefficient (R), mean square error (MSE) and mean absolute error (MAE). It is observed that the ANN model predicts both, the unconfined compressive and Brazilian tensile, strength quite well in the form of R, RMSE and MAE. This study shows that as an alternative to classical modeling techniques, ANN approach can be used accurately for predicting the unconfined compressive strength and Brazilian tensile strength of fiber reinforced cement stabilized fly ash mixes.

인장/압축 하중 하에서 FEA를 이용한 굴곡진 보강섬유를 가진 두꺼운 복합재료의 강도예측에 관한 연구 (Strength Prediction of Thick Composites with Fiber Waviness under Tensile/Compressive Load Using FEA)

  • 류근수;전흥재
    • 한국복합재료학회:학술대회논문집
    • /
    • 한국복합재료학회 2001년도 추계학술발표대회 논문집
    • /
    • pp.129-132
    • /
    • 2001
  • Fiber waviness is one of manufacturing defects encountered frequently in thick composite structures. It affects significantly on the behavior as well as strength of thick composites. The effects of fiber waviness on tensile/compressive nonlinear elastic behavior and strength of thick composite with fiber waviness are studied theoretically and experimentally. FEA(Finite Element Analysis) models are proposed to predict tensile/compressive nonlinear behavior and strength of thick composites. In the FEA models, both material and geometric nonlinearities were incorporated into the model using energy density, iterative mapping and incremental method. Also Tsai-Wu criteria was adopted to predict the strength of thick composites with fiber waviness. Tensile and compressive tests were conducted on the specimens with uniform fiber waviness. It was observed that the degree of fiber waviness in composites significantly affected the nonlinear behavior and strength of the composites

  • PDF

An evolutionary fuzzy modelling approach and comparison of different methods for shear strength prediction of high-strength concrete beams without stirrups

  • Mohammadhassani, Mohammad;Nezamabadi-pour, Hossein;Suhatril, Meldi;shariati, Mahdi
    • Smart Structures and Systems
    • /
    • 제14권5호
    • /
    • pp.785-809
    • /
    • 2014
  • In this paper, an Adaptive nerou-based inference system (ANFIS) is being used for the prediction of shear strength of high strength concrete (HSC) beams without stirrups. The input parameters comprise of tensile reinforcement ratio, concrete compressive strength and shear span to depth ratio. Additionally, 122 experimental datasets were extracted from the literature review on the HSC beams with some comparable cross sectional dimensions and loading conditions. A comparative analysis has been carried out on the predicted shear strength of HSC beams without stirrups via the ANFIS method with those from the CEB-FIP Model Code (1990), AASHTO LRFD 1994 and CSA A23.3 - 94 codes of design. The shear strength prediction with ANFIS is discovered to be superior to CEB-FIP Model Code (1990), AASHTO LRFD 1994 and CSA A23.3 - 94. The predictions obtained from the ANFIS are harmonious with the test results not accounting for the shear span to depth ratio, tensile reinforcement ratio and concrete compressive strength; the data of the average, variance, correlation coefficient and coefficient of variation (CV) of the ratio between the shear strength predicted using the ANFIS method and the real shear strength are 0.995, 0.014, 0.969 and 11.97%, respectively. Taking a look at the CV index, the shear strength prediction shows better in nonlinear iterations such as the ANFIS for shear strength prediction of HSC beams without stirrups.

고강도콘크리트의 재료역학적 특성 연구-변형도율과 인장강도를 중심으로- (The Mechanical Properties of High-Strength Concrete-The Effect of Strain Rate and the Tensile Strength-)

  • 김진근;박찬규;박연동
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 1992년도 가을 학술발표회 논문집
    • /
    • pp.111-118
    • /
    • 1992
  • The mechanical behaviors related to the strain rate effect and the tensile strength of high-strength concrete were investigated in this study. For this purpose, concrete cylinder specimens with 4 different compressive strengths from 232kg/$\textrm{cm}^2$ to 1113kgf/$\textrm{cm}^2$ were tested and analysed on the mechanical properties(stress-strain relationship, compressive, modulus of elasticity, strain at peak compressive stress). From this experimental and analytical study, it seems that the current prediction model(ACI) for modulus of rupture need to be refined. Therefore, more refined equations for evaluation tensile strength of concrete are proposed.

  • PDF

강섬유 보강 초고성능 콘크리트의 탄성계수 및 인장강도 평가 (An Evaluation of Elasticity Modulus and Tensile Strength of Ultra High Performance Concrete)

  • 류금성;유성원
    • 한국건설순환자원학회논문집
    • /
    • 제3권3호
    • /
    • pp.206-211
    • /
    • 2015
  • 최근에 활발히 연구되어지고 있는 UHPC의 경우, 강섬유 혼입량에 의해서 인장강도가 절대적으로 영향을 받는 이유로 본 논문에서는 압축강도, 강섬유량 등을 변수로 하여 압축강도, 탄성계수 및 인장강도 등을 실험적으로 구한 후, 그 결과를 분석하였다. 실험결과에 의하면, 압축강도와 탄성계수 및 인장강도는 비례관계로 상당한 상관성을 가지는 것으로 나타났으며, 섬유혼입률에 따른 압축강도와 인장강도의 관계 역시는 비례관계의 상관성을 가지는 것으로 나타났다. 탄성계수의 경우, 실험결과와 현행 국내 설계기준 식의 차이는 그다지 크지 않은 것으로 나타나, 기존의 설계기준 식을 준용하여도 UHPC 탄성계수 평가에는 큰 문제가 없을 것으로 예상된다. 한편 인장강도의 경우, 현행 설계기준에서 제시되지 않은 이유로 비선형 회귀분석을 실시하여 섬유혼입률을 고려한 인장강도 식을 제안하였으며, 제안된 식은 좋은 상관성을 보이는 것으로 나타났다.

Hashin 파손이론을 이용한 복합재 볼트체결부의 점진적 파손 해석 및 강도 예측 (Progressive Failure Analysis and Strength Prediction based on Hashin Failure Criterion of Bolted Composite Joint)

  • 김성민;김평화;도성철;김형근;박정선
    • 한국추진공학회:학술대회논문집
    • /
    • 한국추진공학회 2017년도 제48회 춘계학술대회논문집
    • /
    • pp.936-938
    • /
    • 2017
  • 본 논문에서는 발사체 및 무기체계의 연소관 등에 적용되고 있는 복합재의 볼트체결부에 대한 점진적 파손 해석을 수행하였다. 해석에 사용된 Hashin 파손 판정식은 복합재 파손모드에 따라 섬유 인장 파손 모드(Fiber tensile failure mode), 섬유 압축 파손 모드(Fiber compressive failure mode), 기지 인장 파손 모드(Matrix tensile failure mode), 기지 압축 파손 모드(Matrix compressive failure mode)의 4가지 모드로 고려되었으며, 이를 이용해 user subroutine인 UMAT을 개발하였다. 점진적 파손 해석을 통해 복합재 볼트체결부에 대한 파손강도를 예측 하였으며, 이를 시편 시험 결과와 비교하였다.

  • PDF