砂质自然煤矸石胶凝材料的研究

Study on spontaneous combustion sandy gangue binding material

以砂质自燃煤矸石和矿渣作为胶凝主体,并以熟石灰、芒硝和水玻璃为激发剂,研制出一种砂质矸石胶凝材料。结果表明,自燃煤矸石和矿渣在水化过程中相互促进,掺入低于50%自燃煤矸石能提高纯矿渣体系的早期强度,并且不降低后期强度;胶凝材料的强度随着激发剂熟石灰量的增加而提高,在熟石灰存在的条件下晶相水化产物是钙矾石,不掺熟石灰水化早期的晶相水化产物主要是石膏,随着水化的进行逐渐生成钙矾石;芒硝掺量为5%时强度达到最大值,而后由于生成较多的钙矾石,产生较大的体积膨胀,导致微裂纹产生,使强度降低。

A sandy gangue binding material has been developed by taking spontaneous combustion sandy gangue and slag as principal part of gelation and using slaked lime,salt cake and water glass as excitant.The result shows that spontaneous combustion gangue and slag inter-promote in the course of hydration,early strength of pure slag system can be increased while its late strength not reduced by adding spontaneous combustion gangue less than 50%,the strength of binding material improves with increasing amount of slaked lime of excitant,ettringite is product of crystalline phase hydration under the existence of slaked lime and gypsum is main product of crystalline phase hydration at early stage of hydration without slaked lime,ettringite is gradually formed with progress of hydration;when the amount of salt cake is 5% the strength is up to its maximum and after that large volume expansion create micro crack and reduce the strength due to production of more ettringite.