为探究专用塑化剂对盾构隧道壁后注浆浆液性质的影响，通过室内试验对塑化剂不同掺量的同步注浆浆液性质进行测定，并通过固结试验装置探究改良后浆液在不同地层中的固结特性。研究表明： 1）盾构隧道盾尾壁后注浆专用塑化剂能够在不影响浆液强度的前提下，缩短浆液的凝结时间，随着塑化剂添加量的提高，浆液的泌水率、稠度、流动度都有减小的趋势； 2）专用塑化剂的最优掺量为0.4%~1.2%，在该范围添加量下，浆液的性能得到进一步提升，凝结时间会缩短； 3）改良后浆液在地层中的固结时间、沉降量、强度与地层性质相关，在粉质黏土、粉砂与粗砂3种地层中，改良后浆液固结完成时间依次减小，最终体积收缩率依次增大，28 d无侧限抗压强度依次减小。

 A laboratory test is conducted to determine the properties of grout with different amounts of plasticizer to analyze the influence of a special plasticizer on the properties of shield tunneling grout. Moreover, the consolidation characteristics of the improved grout in different strata are analyzed. The results show the following: (1) The special plasticizer for the shield tunnel grout can shorten the setting time of the grout without affecting the grout strength. The bleeding rate, consistency, and fluidity of the grout decrease with a reduction in the plasticizer amount. (2) The optimal amount of special plasticizer is 0.4 %~1.2 %, which can greatly improve the gout performance and shorten the grout setting time. (3) The improved grout′s consolidation time, settlement, and strength are closely related to the ground properties. The consolidation completion time and the 28day unconfined compressive strength of the improved grout in silty clay, silty sand, and coarse sand formations decrease in turn, whereas the final settlement increases in turn.