Micro-crystalline to crypto-crystalline quartz exists always in dolomitic limestones. When the dolomitic limestones are used as aggregates of concrete, pore solutions mainly composed of K+, Na+, Ca2+ and OH− ions may interacts simultaneously with dolomite and micro-crystalline to crypto-crystalline quartz. To understand mechanisms of alkali-silica-dolomite reactions in concrete, chemical reaction products in system of CaMg (CO3)2-SiO2-Ca(OH)2-KOH-NaOH-H2O cured at 20 °C, 38 °C and 60 °C were analyzed by X-ray diffraction, infrared spectroscopy, differential scanning calorimeter-thermo gravity and scanning electron microscope. Results show that magnesium derived from dolomite was mainly incorporated in brucite and silicon derived from micro-crystalline to crypto-crystalline quartz was in alkali-silica gel. No evident magnesium silicate gels were detected under high alkaline condition. It is expected that magnesium silicate gels will not be formed accompanying with alkali-silica/dolomite reaction in concrete. Reaction in dolomite-quartz system is a superposition of ASR and ACR.

中文翻译：

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在碱性条件下，是否在白云石-石英体系下产生所谓的 Mg[sbnd]Si 凝胶


微晶到隐晶石英总是存在于白云质石灰岩中。当白云质石灰岩用作混凝土的聚集体时，主要由 K+、Na+、Ca2+ 和 OH− 离子组成的孔隙溶液可能与白云石和微晶到隐晶石英同时相互作用。为了解混凝土中碱-二氧化硅-白云石反应的机理，采用X射线衍射、红外光谱、差示扫描量热仪-热重和扫描电子显微镜分析了在20 °C、38 °C和60 °C固化的CaMg（CO3）2-SiO2-Ca（OH）2-KOH-NaOH-H2O体系中的化学反应产物。结果表明，白云石衍生的镁主要掺入水镁石中，碱硅胶中含有微晶到隐晶石英衍生的硅。在高碱性条件下未检测到明显的硅酸镁凝胶。预计硅酸镁凝胶不会在混凝土中伴随着碱-二氧化硅/白云石反应而形成。白云石-石英体系中的反应是 ASR 和 ACR 的叠加。