Experimental Measurements On The Permeability Coefficient Of A Concrete Sample Under Low Pressure Differences
نویسندگان
چکیده
This paper presents preliminary experimental results on the measurement of the air permeability coefficient in a concrete sample that has been subjected to constant pressure differences of 5 and 10 Pa (3.45 x 1 0 ' ~ 6.90 x 1u2 psi). This experimental model simulates indoor radon gas entry by advection. A reliable air permeability system was designed to perform laboratory measurements on concrete samples under controlled conditions. The experimental setup. consisted of a PC-data acquisition and control system, proportional needle valves, highly accurate pressure transducers, and a commercial visual programming language software package. The concrete sample tested was approximately 4" in length. 3.5" in diameter, and of standard 1:2:4 (cement:sand:pea gravel) composition with a water-to-cement ratio of 0.5. A comparison between past and present air permeability coefficient results is presented. Details of the innovative experimental setup and procedures are described.
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