شناسنامه مقاله

اسم مقاله:

RETROFITTING OF MASONRY WALLS

مولف یا نویسنده:

Iman elyasian structural engineer

مترجم:                                                                                                       

چاپ و انتشار:

چکیده:

Existing masonry buildings around the world, many of which are of historical and architectural value, may not have adequate resistance against seismic and wind loads. In the following sections some studies on masonry walls retrofitted with conventional methods and with FRP composites are briefly described.

واژگان کلیدی:

RETROFITTING, MASONRY WALLS, FRP

مقدمه:

نتیجه گیری:

The  use  of  FRP  composites  for  the  retrofitting  of  masonry  structures  offers  some  advantages  compared  to  the  use  of  conventional  retrofitting  techniques. As  an example, FRP composites do not add considerable mass to the structure.  This extra weight could modify the dynamic response to seismic events, which may be observed when  using  masonry-  RC  composite  walls  or  ferrocement  overlays.    From  the architectural  point  of  view,  the  use  of  conventional  methods  may  violate  the aesthetics of building facades and they may intrude on usable space adjacent to the strengthened  components.    The  aforementioned  facts  along  with  the  outstanding properties  of  FRP  materials  make  the  use  of  FRP  composites  attractive  for strengthening of masonry structures. Studies  on  masonry  walls  strengthened  with  FRP  composites  have  shown  that increases  in  either  out-  of-  plane  or  in  plane  capacities  as  well  as  ductility  can  be achieved.  However, most of these studies have been carried out in laboratories, under ideal conditions such as considering free rotation of the supports.  In this sense, some tests performed in this investigation offered an opportunity to observe the behavior of masonry walls under real boundary conditions, which are not commonly reproduced in the laboratory.

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سال انتشار:

چند خط متن:

Hamid (1996) conducted an investigation aimed at strengthening of hollow concrete block walls using, similar to basement walls.  As a vertical reinforcement # 4 FRP rods were used to strengthen a URM wall because of their corrosion resistance and ease of installation.  The strengthening procedure consisted of: (1) cutting slots at the top course of the wall to place the reinforcing bars, (2) inserting the rods, (3) drilling holes of 2- in. diameter thorough the height of the cells to pump the grout; and (4) pumping grout starting from the lower holes; plug the holes after grouting to continue with the upper holes.  The 4 by 8.5-ft. walls were simply supported and tested under out-of- plane loading. In the strengthened wall, a 22-fold increase in flexural capacity compared to the unstrengthened wall was recorded.  In addition, a large deformation capability  beyond  the  first  crack  was  observed,  as  seen  in  Figure  ۱۳.    This  is attributed to the presence of the reinforcing bars and the high tensile strength of the grout.