Numerical investigation of soil plugging effect inside sleeve of cast-in-place piles driven by vibratory hammers in clays.

During driving sleeve of cast-in-place piles by vibratory hammers, soils were squeezed into sleeve and then soil plugging was formed. The physic-mechanical properties of the soil plug have direct influence on the load transmission between the sleeve wall and soil plug. Nevertheless, the researches on this issue are insufficient.

[Study on the prevalence and risk factors of "subhealth" status in college and university staff in Guangdong province].

Objective: To understand the current status and risk factors of "subhealth" in college and university staff in Guangdong province.

Methods: Eight thousand four hundred and seventeen staff in 19 colleges and universities in Guangdong were investigated through a self-developed questionnaire, and statistically analyzed using chi(2) test, chi(2)(strand) test and odd ratio. Judgement was based on the criteria on "subhealth" through Delphi method.