In this study alkali-activated concrete mixtures with a high calcium-based precursor and with prolonged workable times were developed and its site application for pumping activity was validated through a field study. This was achieved by formulating mixtures with pumpable workability and extended workable times. Sodium gluconate was used as a retarder to extend the workable time. The influence of sodium gluconate on the fresh properties of alkali-activated paste mixtures, such as setting time, spread diameter retention, yield stress, apparent viscosity and the evolution of storage modulus, was investigated. The effect of sodium gluconate on the pore solution composition and its pH and the amount and type of hydration products in alkali-activated systems were also studied using inductively coupled plasma atomic emission spectroscopy (ICP-AES), thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR). Zeta potential measurements were also performed to understand the adsorption of sodium gluconate and its impact on the surface charge of GGBFS particles. The studies on paste revealed that sodium gluconate is an effective retarder that prolongs the setting and workable times. Zeta potential and rheological studies illustrated the dispersive property of sodium gluconate. The experiments were also performed on concrete systems to understand the slump retention and compressive strength. Concrete mixtures with compressive strength in the range of 38–46 MPa at 28 days and a spread diameter above 350 mm retained at 150 min were obtained. Further, the developed concrete mixture was evaluated for pumpability by pumping the concrete through a pipe conduit after a long-haul time of 180 min. The effective pumping of the formulated alkali-activated concrete mixes shall facilitate the practical use of alkali-activated materials in construction projects. The durability performance of the developed pumpable alkali-activated GGBFS concrete mixture was also evaluated by measuring the carbonation depth, the chloride migration coefficient and performing rapid chloride penetration test on the extracted core samples after exposure to natural weathering for 510 days.

中文翻译：

---

以葡萄糖酸钠为缓凝剂的可泵送碱活化磨粒化高炉矿渣粘结剂基混凝土的开发与现场验证


在这项研究中，开发了具有高钙基前体且工作时间长的碱活化混凝土混合物，并通过现场研究验证了其用于泵送活动的现场应用。这是通过配制具有可泵送可加工性和延长可加工时间的混合物来实现的。以葡萄糖酸钠为缓凝剂，延长工作时间。研究了葡萄糖酸钠对碱活化糊状混合物新鲜特性的影响，如凝结时间、展布直径保持、屈服应力、表观粘度和储能模量的演变。此外，还使用电感耦合等离子体原子发射光谱 （ICP-AES） 、热重分析 （TGA） 和傅里叶变换红外光谱 （FTIR） 研究了葡萄糖酸钠对孔隙溶液组成及其 pH 值以及碱活化系统中水合产物的数量和类型的影响。还进行了 Zeta 电位测量以了解葡萄糖酸钠的吸附及其对 GGBFS 颗粒表面电荷的影响。对糊状物的研究表明，葡萄糖酸钠是一种有效的缓凝剂，可延长凝固和使用时间。Zeta 电位和流变学研究表明葡萄糖酸钠的分散特性。还在混凝土系统上进行了实验，以了解坍落度保持和抗压强度。混凝土混合物在 28 天时抗压强度在 38-46 MPa 范围内，在 150 min 时保持 350 mm 以上的铺展直径。此外，通过在 180 分钟的长途运输时间后将混凝土泵送通过管道来评估开发的混凝土混合物的可泵送性。 配制的碱活化混凝土混合物的有效泵送应有利于碱活化材料在建筑项目中的实际使用。通过测量碳化深度、氯化物迁移系数，并对提取的岩心样品进行自然风化 510 d 后的快速氯化物渗透试验，评价了所开发的可泵送碱活化 GGBFS 混凝土混合物的耐久性能。