采用石灰中和改性二水磷石膏，再添加水泥、机制砂及增塑剂制备水泥基湿拌抹灰砂浆，分析了磷石膏、水泥及增塑剂不同掺量下湿拌砂浆的凝结时间、稠度以及力学强度等物理性能，并采用X射线衍射（XRD）及扫描电镜（SEM）分析了磷石膏在湿拌砂浆中的作用机理。结果表明，随着磷石膏用量增加，湿拌砂浆的凝结时间延长，28 d抗压强度及14 d拉伸黏结强度降低；随着水泥用量增加，砂浆的凝结时间缩短，强度逐渐增大；随着增塑剂用量的增加，砂浆的黏结性能及润滑性能逐步优异，凝结时间逐渐增加。当控制材料掺量比例（质量分数）磷石膏为35%、机制砂为48%、水泥为17%、外掺石灰为2%、增塑剂为0.3%时，砂浆的凝结时间为25 h，28 d抗压强度为6.2 MPa，14 d拉伸黏结强度为0.31 MPa，均符合行业标准JC/T 230—2007《预拌砂浆》中WP M5质量技术指标要求。磷石膏在水泥基湿拌砂浆中的主要作用是参与反应的磷石膏提供硫酸根并与水化铝酸钙反应生成钙矾石，形成提高砂浆强度的矿物起胶结作用，未反应的磷石膏作为细集料起填充作用。

Cement?based wet?mixed plastering mortar was prepared by neutralizing and modifying dihydrate phosphogypsum with lime and adding cement，manufactured sand and plasticizer.The physical properties such as setting time，consistency and mechanical strength of the wet?mixed mortar with different dosages of phosphogypsum，cement and plasticizer were investigated，and the action mechanism of phosphogypsum in the wet?mixed mortar was analyzed by X-ray diffraction（XRD） and scanning electron microscopy（SEM）.The results showed that with the increase of phosphogypsum content，the setting time of the wet?mixed mortar was prolonged，and the 28-day compressive strength and the 14-day tensile adhesive strength of the wet?mixed mortar were decreased.With the increase of cement content，the setting time of wet?mixed mortar decreased，and the strength increased gradually.With the increase of plasticizer dosage，the bonding properties and lubrication of wet?mixed mortar became gradually excellent，and the setting time increased.When the controlling material proportion（mass fraction） was phosphogypsum of 35%，manufactured sand of 48%，cement of 17%，and external addition lime of 2%，plasticizer of 0.3%，the setting time of mortar was 25 h，28 d compressive strength was 6.2 MPa，14 d tensile bonding strength was 0.31 MPa，all of which met the requirements of WP M5 quality and technical indicators in the industrial standard JC/T 230—2007 Pre?mixed Mortar.Phosphogypsum in cement?based wet?mixed mortar played a cementing role by providing sulfate ions to react with calcium aluminate hydrate to generate mortar strength minerals ettringite.Unreacted phosphogypsum acted as fine aggregate filler.