Abstract: This paper gives integral strata deformation pattern and slumping arch strata deformation pattern based on the strata deformation characteristics in urban subway using shallow tunnel construction method. Mechanical models, stability features, major influencing factors and settlement curves of strata are also given，which can perfectly explain the characteristics and patterns of strata deformation, and reveal the mechanics of large deformation and surface subsidence in clay soil and sandy soil. It is shown that strata deformation is usually caused by the destabilization and destruction of structure strata. The strata structures act as beam in integral settlement pattern, while pressure arch in slumping arch deformation pattern. Thereby the beam or arch stabilization is the core of ground settlement control; and respectively the emphases are strengthening beam bearing point and in-time complementally grouting in bed separation region, as well as controlling the stability of arch springing strata. With the merits of these models we can offer strata deformation control standards and environmental evaluation criterion. Based on the typical project of sector 6 and sector 3A of the first-stage subway construction in Shenzhen, good result is achieved successfully in strata deformation control of both patterns; meanwhile available suggestion is proposed on the strata deformation control standard of Shenzhen Subway as well as other urban underground works. The achievement of this paper will be the prevalent guidance to environmental control in urban underground engineering.

Key words: Shenzhen Subway, shallow tunnel construction, strata deformation pattern, environmental evaluation, control standard