نوع مقاله : یادداشت فنی
نویسندگان
1 دانشکده ی مهندسی عمران،دانشگاه فردوسی،مشهد
2 دانشکده ی مهندسی عمران، دانشگاه فردوسی مشهد
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
The present study investigates the punching shear behavior of flat slabs
strengthened by ECC concrete. In addition, it studies the effect of magnetic
water in a mixture of ECC concrete. In the experimental part of the study, nine
reinforced concrete slab specimens with the dimensions of $1000times1000$
mm with the same reinforcement ratio were constructed and tested. The
reinforcement ratio of the slabs was . The slab thickness varied in different
specimens. One specimen with mm thickness was made of plane concrete. Six
specimens were made by combining the plane concrete and ECC concrete layers
with different thicknesses of and mm. Two of the specimens were made by ECC
concrete with mm thickness. The mixture of plane concrete incorporated an
ordinary Portland cement with a water-cement matrix ratio of . This ratio was
for ECC Concrete. In some specimens, the U-shaped shear studs were used for a
better connection between the ECC concrete and plane concrete layers. ECC
concrete has been used on the tension side of the slabs. Both punching shear
strength and displacement of each specimen were measured by a Linear Variable
Displacement Transducer (LVDT). During the punching shear tests, the load and
maximum deflection were recorded by a data acquisition system and onsequently,
the load-displacement curves were drawn. The tests were conducted using a
testing machine to apply the load at an average rate of kg/sec. A hydraulic
jack was fixed to the frame and used to apply the concentric load on the column
stub. The hydraulic jack had a maximum capacity of kN. The results of the tests indicated that the ECC concrete enhanced the punching shear strength of
slabs. The magnetic water improved the ECC concrete flow and load-carrying
capacity of the slabs. U-shaped shear studs increased the load-carrying
capacity of the specimens.
کلیدواژهها [English]
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