With urban tunneling for a variety of infrastructure projects, there is increasing demand for underground space. This inevitably leads to the requirement to demonstrate that construction of proposed tunnels above existing ones does not result in adverse impacts, both structural and operational, on these structures. Recently there has been a push to undertake detailed 3D numerical analysis for such investigation. This paper outlines a simplified, 2D approach that can be adopted for undertaking a technical check and assessment of potential damage focusing on unbolted wedge-block lined tunnels in clay. The approach couples 2D numerical analysis with well-established closed form solutions resulting in a pseudo-3D analysis. This method can be used to simply predict the integrity of unbolted, wedge-block linings subject to internal water pressure, due to over-tunneling.
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