华南理工大学学报(自然科学版)
華南理工大學學報(自然科學版)
화남리공대학학보(자연과학판)
JOURNAL OF SOUTH CHINA UNIVERSITY OF TECHNOLOGY(NATURAL SCIENCE EDITION)
2014年
2期
74-80
,共7页
混凝土%徐变%松弛%变系数广义开尔文模型%龄期
混凝土%徐變%鬆弛%變繫數廣義開爾文模型%齡期
혼응토%서변%송이%변계수엄의개이문모형%령기
concrete%creep%relaxation%generalized Kelvin model with variable coefficients%age
首先,提出了一个基于变系数广义开尔文模型的混凝土徐变度Dirichlet级数表达式,并依据延迟范围理论建立了九参数徐变度公式;然后,推导了松弛系数率的表达式,并在此基础上提出了计算松弛系数的率型迭加算法;最后,基于试验数据将文中建议的徐变度表达式以及率型迭加算法与常用的徐变度公式以及计算松弛系数的迭加算法进行了比较。结果表明:提出的徐变度表达式物理概念清晰且能避免负徐变;九参数徐变度公式的拟合精度高于常用的八参数徐变度公式;率型迭加算法避免了普通迭加算法的误差传递现象,大幅度提高了早龄期混凝土持载时间较长时的拟合精度。
首先,提齣瞭一箇基于變繫數廣義開爾文模型的混凝土徐變度Dirichlet級數錶達式,併依據延遲範圍理論建立瞭九參數徐變度公式;然後,推導瞭鬆弛繫數率的錶達式,併在此基礎上提齣瞭計算鬆弛繫數的率型迭加算法;最後,基于試驗數據將文中建議的徐變度錶達式以及率型迭加算法與常用的徐變度公式以及計算鬆弛繫數的迭加算法進行瞭比較。結果錶明:提齣的徐變度錶達式物理概唸清晰且能避免負徐變;九參數徐變度公式的擬閤精度高于常用的八參數徐變度公式;率型迭加算法避免瞭普通迭加算法的誤差傳遞現象,大幅度提高瞭早齡期混凝土持載時間較長時的擬閤精度。
수선,제출료일개기우변계수엄의개이문모형적혼응토서변도Dirichlet급수표체식,병의거연지범위이론건립료구삼수서변도공식;연후,추도료송이계수솔적표체식,병재차기출상제출료계산송이계수적솔형질가산법;최후,기우시험수거장문중건의적서변도표체식이급솔형질가산법여상용적서변도공식이급계산송이계수적질가산법진행료비교。결과표명:제출적서변도표체식물리개념청석차능피면부서변;구삼수서변도공식적의합정도고우상용적팔삼수서변도공식;솔형질가산법피면료보통질가산법적오차전체현상,대폭도제고료조령기혼응토지재시간교장시적의합정도。
In this paper,first,a Dirichlet series expression of concrete creep based on the generalized Kelvin mod-el with variable coefficients is suggested,and a creep expression with nine parameters is proposed based on the con-tinuous retardation spectrum.Then,an expression of relaxation coefficient rate is derived and a rate-type superposi-tion algorithm is further proposed to calculate the relaxation coefficient.Finally,by using some experimental data, the suggested creep expression and the rate-type superposition algorithm are respectively compared with the common ones.The results indicate that (1 )the proposed creep expression possesses explicit physical meaning and helps to avoid negative creep;(2)the creep expression with nine parameters is of higher fitting precision,as compared with the expression with eight parameters;and (3 )the proposed rate-type superposition algorithm helps to avoid the er-ror propagation existing in the traditional superposition algorithm and greatly improves the fitting precision of the early-age concrete at longer lag-time stage.