To check the protective performance of shallow-buried steel bars reinforced concrete urban utility tunnel (UUT) under accidental explosion, a scaled shallow-buried UUT was designed, constructed and tested. In-field explosion experiments were carried out on this UUT. Dynamic responses, damage evolutions and failure styles of the UUT were revealed by the experiments. The tunnel roof is the most vulnerable component with longitudinal main cracks developing along the tunnel. When the scaled distance was larger than 1.10 m/kg^1/3, no cracks appeared and the UUT was intact. When the scaled distance was reduced, the damage degree became more and more serious with longitudinal crack number developing from one at 1.000 m/kg^1/3, two at 0.881 m/kg^1/3, to three at 0.800 m/kg^1/3. At 0.557 m/kg^1/3 the width of the central crack abruptly increased to 11.2 mm and the UUT was seriously damaged. Damage level can be classified by the mid-span displacements of the roof, the width and number of the roof cracks, the accelerations and the maximum strains. The roof was simplified as an elastically restrained one-way slab. The Euler beam theory was adopted to analyze the dynamic responses, which are in agreement with the experiments in the first three cases.

为了检查浅埋钢筋混凝土城市公用事业隧道（UUT）在意外爆炸下的防护性能，设计，建造和测试了一个按比例缩放的浅埋UUT。在此UUT上进行了现场爆炸实验。实验揭示了被测部件的动态响应，损伤演化和失效方式。隧道顶板是最脆弱的部分，沿隧道会产生纵向主裂纹。当标度距离大于1.10 m / kg ^1/3时，没有出现裂纹并且UUT完好无损。当减小标度距离时，破坏程度变得越来越严重，纵向裂纹数从1.000 m / kg ^1/3处的两个，在0.881 m / kg ^1/3处的两个处发展，至0.800 m / kg ^1/3的三倍。在0.557 m / kg ^1/3时，中心裂纹的宽度突然增加到11.2 mm，UUT受到严重损坏。破坏程度可以通过屋顶的中跨位移，屋顶裂缝的宽度和数量，加速度和最大应变来分类。屋顶简化为弹性约束的单向平板。采用欧拉梁理论对动力响应进行分析，与前三种情况的实验结果吻合。