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根据颗粒堆积原理计算了碱白云石反应引起的固相框架体积的变化，并用图象分析技术研究了反应产物间的孔隙体积。研究了碱白云石反应机理，从热力学和通过实验分析了溶液ｐＨ值对碱白云石反应程度与速率的影响。通过监测白云岩粉末样压实体和基本不含粘土及石英的白云质灰岩在碱溶液中的膨胀行为，研究了碱白云石反应本身的膨胀性。评估了低碱度的硫铝酸盐水泥对碱白云石反应的抑制作用。结果表明：球形产物如呈最紧密堆积，则固体产物的孔隙率为２５．９５％，碱白云石反应后固相框架体积将增加２９．２３％。实际上，固体产物的孔隙率为１５％，反应后固相框架体积将增加１２．５％，这为反应产生膨胀提供了前提条件。白云石与碱作用生成水镁石、方解石和碳酸碱，该过程能直接引起膨胀。反应和膨胀的速率取决于溶液的ｐＨ值，ｐＨ值越高，反应和膨胀越快，当ｐＨ值低于某一值后，碱白云石反应将不发生，相应地，岩石不产生膨胀。碱白云石反应膨胀的驱动力为去白云化反应生成的方解石和水镁石晶体在受限空间生长产生的结晶压力。硫铝酸盐水泥能有效地抑制碱白云石反应膨胀，从而能防止混凝土的开裂破坏。
Based on the principle of particle deposition, the change of the volume of the solid phase frame caused by the alkali-dolomite reaction was calculated, and the pore volume between the reaction products was studied by image analysis techniques. The alkali-dolomite reaction mechanism was studied, and the effect of the pH of the solution on the reaction rate and rate of alkali-dolomite was analyzed from the thermodynamics and experiments. The swelling behavior of the alkali-dolomite reaction itself was investigated by monitoring the swelling behaviour of dolomite powder-like compacted bodies and dolomitic limestones essentially free of clay and quartz in alkaline solutions. The inhibitory effect of low alkalinity sulphoaluminate cement on alkali-dolomite reaction was evaluated. The results show that if the spherical product is the closest packing, the porosity of the solid product is 25.95%. After the alkali-dolomite reaction, the volume of the solid phase frame will increase by 29.23%. In fact, the porosity of the solid product is 15%, and the volume of the solid phase frame will increase by 12.5% after the reaction, which provides a prerequisite for the expansion of the reaction. Dolomite reacts with alkali to produce brucite, calcite, and carbonate, which can directly cause swelling. The rate of reaction and expansion depends on the pH of the solution. The higher the pH, the faster the reaction and swelling. When the pH is lower than a certain value, the alkali-dolomite reaction will not occur, and accordingly, the rock will not expand. The driving force for the expansion of the alkali-dolomite reaction is the crystallization pressure generated by the dolomitization and brucite crystals generated in the dolomitization reaction in a confined space. The sulphoaluminate cement can effectively inhibit the expansion of the alkali-dolomite reaction, thereby preventing cracking of the concrete.