预测粉煤灰混凝土强度的双参数模型  

DOUBLE PARAMETER MODEL PREDICTING STRENGTH OF CONCRETE WITH FLY ASH

作　　者：朱力[1] 杨英青[1] 张洪庆[1] 王敏[1] 袁铁映[1] 

机构地区：[1]中南大学土木建筑学院,长沙410075

出　　处：《工业建筑》2009年第S1期859-863,880,共6页Industrial Construction

摘　　要：研究龄期为7,28,60,140,210 d,粉煤灰取代水泥、取代细骨料和混合取代三种取代方式下混凝土抗压强度的发展状况,建立预测混凝土抗压强度增长因子双参数模型。结果表明:龄期与取代率对强度增长因子的影响是相互独立的;强度增长因子随龄期的增长而增大;取代水泥时,强度增长因子随取代率的增大而减小;取代细骨料时,强度增长因子随取代率的增大先增大后减小,最大值点在20%左右;取代细骨料对强度的增长较取代水泥有利;继而建立了混合取代方式下强度增长因子预测模型,引入取代率权重变化因子,其只与龄期有关,混合取代得到的强度增长因子介于取代水泥和取代细骨料得到的二者之间,且随龄期的增长,粉煤灰取代细骨料对强度的作用效应愈发增强。The development of compressive strength of concrete is studied under 3 substitution ways of substituting fly ash for cement and fine aggregate and mix substitution on the basis of 5 ages(7 d,28 d,60 d,140 d and 210 d).It is established a double parameter model predicting strength growth factor of concrete.Results indicate that the effects on strength growth factor caused by ages and substitution rate are respective;strength growth factor increases with the increasing of ages;when substituting fly ash for cement,strength growth factor reduces with the increasing of substitution rate;when substituting fly ash for fine aggregate,strength growth factor increases firstly and then reduces with the increasing of substitution rate,when substitution rate is about 20%,strength growth factor is maximum;substituting fly ash for fine aggregate is more advantageous than substituting fly ash for cement to the increasing of strength of concrete;it is established a forecast model for predicting strength growth factor of mix substitution,and cited a substitution rate weight change factor that is only related with ages,strength growth factor of mix substitution is between that of substituting fly ash for cement and that of substituting fly ash for fine aggregate,and the effect on the strength of substituting fly ash for fine aggregate is increasing with the increasing of ages.

关 键 词：粉煤灰 混凝土强度增长因子 双参数模型 混合取代 取代率权重变化因子 

分 类 号：TU528.2[建筑科学—建筑技术科学]