双圆盾构隧道土体地表沉降特性

Characteristics of Soil Surface Settlement for Double-O-Tube Shield Tunnel

介绍了双圆盾构隧道这种新型隧道形式,与圆形盾构隧道相比,双圆盾构隧道具有占用地下空间小、施工效率高、掘削土量少等优点,但双圆盾构隧道引起的土体位移相对较大,影响范围也比较广。基于双圆盾构隧道的施工特点,通过计算圆形盾构的土体地表沉降,运用土体位移叠加法,研究了双圆盾构隧道引起的土体地表沉降的特性,建立了双圆盾构隧道直径、埋深和地层损失等因素与土体地表沉降的关系。结果表明:双圆盾构隧道的地表沉降槽的形态与圆形盾构隧道相似;双圆盾构隧道的地表沉降量大,影响范围广;双圆盾构隧道的地表沉降与埋深和直径之比有关。

Double-o-tube （DOT） shield method is a new method to construct tunnel in the development of underground space. DOT shield tunnel has many advantages, such as less underground space occupancy, higher construction efficiency, less soil excavation, etc, but larger surface settlement and larger disturbance of soils exist in the construction of DOT shield tunnel. Based on the characteristics of the DOT shield tunnel construction, the soil surface settlement was studied using the method of the displacement overlapping. The relationship between the soil surface settlement and the tunnel depth, the tunnel diameter and the gap parameter was also derived. It is shown that the soil surface settlement curve of DOT shield tunnel is similar with that of circle tunnel; the soil surface settlement and the width of the settlement trough of DOT shield tunnel are larger than those of circle tunnel, and the soil surface settlement of DOT shield tunnel is related to the ratio of the depth to diameter of tunnel.