| Concrete Small Hollow Block (CSHB) is an environment-protected building material with lots of advantages such as saving of energy, no consuming of clay soil, and increasing area. It will become a structural system in future. Recently, the application and development of Concrete Small Hollow Block Building (CSHBB) has been emphasized by National Ministry of Construction. However, the problem of cracks in CSHBB had badly restricted its development. For this reason, it is necessary to further study the problem of cracks in CSHBB. Although the styles of cracks are multiple, the experimental study and analysis on shrinkage of Concrete Small Hollow Block Wall (CSHBW) are focused in this paper.On the base of the field investigation and the tests achieved by Institute of Structural Engineering, Zhejiang University, the styles of shrinkage cracks in the CSHBB are summarized. At the same time, the primary control methods are classified by the three aspects such as material, structural design, construction and use.Shrinkage experiment in CSHBW has been carried out. The primary characteristics of experimental study which is different from the former study is that the relative humidity (RH) is kept invariableness. A room to ensure invariable relative humidity is built by ourselves, and shrinkage deformation has been gained in CSHBW with the same dimension and different construction. Based on experimental data, the shrinkage ratios of CSHBW are gained. Compared with the shrinkage ratios of different construction in CSHBW, it can be concluded that using duration surfacing material is an effective method to decrease the deformation of CSHBW. Moreover, the shrinkage function which reflects the effect of RH to CSHBW is gained.Also, the methods of calculating shrinkage stress have been summarized.Deformation of masonry block walls is analyzed by Finite Element Method (FEM). The results fit well with those from experiment. So it is available to the project application.
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