为满足2017年版《铁路工程预算定额 （第3册 隧道工程）》中关于喷射混凝土和衬砌混凝土工程数量计量的相关规定，研究探讨统一的超挖回填数量及费用的计算规则。以350 km/h客运专线双线隧道通用参考图为基础，结合相关设计规范、施工技术规程,提出简便实用的允许超挖和预留变形工程量、回填工程量及其费用的计算规则，并对比分析不同级别围岩超挖回填的工程数量及费用与采用旧定额计算时的差异。结果表明： 采用新定额，Ⅱ、Ⅲ级围岩超挖回填数量减少，Ⅳ、Ⅴ级围岩超挖回填数量增加，超挖回填定额直接费增长700～1 100元/延米。

In order to meet the related engineering quantity computing rules of shotcrete and lining concrete in TZJ 20032017 Budget Quota of Railway Project (Chapter 3: Tunnel Engineering), the unified calculation rules of backfill quantity and cost of tunnel overbreak is studied. Based on the general referenced sketch of doubletrack tunnel of 350 km/h passengerdedicated line and related design codes and construction technology regulations, the simple and convenient calculation rules of quantities of allowable overbreak and reserved deformation and quantity and cost of tunnel backfill are proposed; and the quantity and cost of tunnel backfill under different surrounding rock grades calculated by new and existing budget quota are compared. The results show that by adopting the new budget quota, the quantity of tunnel backfill decreases under surrounding rock grades of Ⅱand Ⅲ, while increases under surrounding rock grades of Ⅳ and Ⅴ, and the quota cost of tunnel backfill increases by RMB 700 per meter to RMB 1 100 per meter.