<p>The emergence of new clay-resistant sacrificial agents has been paid extensive attention in the engineering of concrete. In this study, N-spiraling quaternary ammonium PQA and bicationic spiraling quaternary ammonium salt BPQA were synthesized via Menshutkin reaction through two steps of spirocyclization and quaternization. The molecular structure of the synthesized salt was discerned through Fourier transform infrared spectroscopy and nuclear magnetic spectrum. In cement slurry containing clay, the spiro quaternary ammonium salt was used as sacrificial agent which combined with polycarboxylate superplasticizer(PCE) to evaluate its effect on dispersion efficiency. The results reveal that the incorporation of PQA or BPQA can obviously improve the initial dispersion efficiency of PCE. When the dosage of BPQA exceeds 0.15%, the fluidity decreases to a certain extent, indicating that the optimal dosage of BPQA is about 0.15%. Specifically, BPQA has notable effect on the dispersion retention. Both the adsorption and Zeta potential analysis of slurry were adopted to determine the clay-resistant mechanism of PCE. The action principle of sacrificial agent with spiro is explained by theoretically-based model. The quaternary ammonium salt of aza-helices has not only high-density cationic functional groups, but also intra-ring tension effect and ring steric hindrance effect. This study provides valuable insights for improving the clay adaptability of PCE and thus broadening the application of PCE.</p>