| The cracks emerge easily in large volume concrete structure construction, which has been proved by many construction projects. Construction will suffer a lot loss due to the concrete cracks. People are urgent to study why crack will happen and to seek actively the methods and ways of crack-prevention. In this paper, the underground cabinet structure of the city tunnel is studied on basis of the predecessor's studies. With the theory analysis, the characteristics of large volume concrete crack and crack-prevention methods are introduced briefly. Several kind factors of influencing tunnel concrete crack are discussed in respect of material and mechanics properties. By the heat conduction equation, temperature field of tunnel concrete wall is analyzed with the actual boundary conditions. The influencing factors of the wall's temperature are also discussed. The reasons and characteristics of the tunnel concrete crack are further analyzed on the basis of temperature field distribution. The calculation model of temperature shrink stress for the concrete wall is established in combination with the boundary condition of tunnel reinforced concrete bottom plate. The calculation formula of temperature stress for the concrete wall and wall-length without temperature-seem are derived. Finally, the specific measures for controlling tunnel concrete temperature shrink are synthetically put forward in design, raw materials, construction and spot inspection etc. Controlling measures for temperature shrink crack are synthetically applied in Suzhou-Nan-Huan tunnel construction project. It shows the measures presented in this paper for controlling temperature shrink cracks of tunnel wall are feasible and rational in the practical engineering.
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