This paper presents a constitutive model for the simulation of temperature and relative humidity effects on concrete expansion due to Alkali–Silica Reaction (ASR). The model was formulated within the multiphysics framework of the Lattice Discrete Particle Model (LDPM). LDPM simulates concrete internal structure at the mesoscale defined as the length scale of coarse aggregate pieces. As such it accounts for the heterogeneous character of ASR expansion, cracking and damage, creep, hygrothermal deformation as well as moisture transport and heat transfer. The overall framework was calibrated and validated by comparing several numerical simulations with a large database of experimental data gathered from the literature. The proposed model is able to capture accurately all available experimental evidence, including: (a) the increase of expansion rate for increasing temperature and its marked decrease for decreasing relative humidity; and (b) both increase or decrease of ASR ultimate expansion as function of temperature.

本文提出了一种本构模型，用于模拟温度和相对湿度对碱-二氧化硅反应 (ASR) 引起的混凝土膨胀的影响。该模型是在晶格离散粒子模型 (LDPM) 的多物理场框架内制定的。LDPM 在定义为粗骨料块长度尺度的中尺度上模拟混凝土内部结构。因此，它解释了 ASR 膨胀、开裂和损坏、蠕变、湿热变形以及水分输送和传热的异质性。通过将几个数值模拟与从文献中收集的大型实验数据数据库进行比较，对整体框架进行了校准和验证。所提出的模型能够准确地捕获所有可用的实验证据，包括：(a) 温度升高膨胀率增加，相对湿度降低则显着降低；(b) 作为温度函数的 ASR 极限膨胀的增加或减少。