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pre-cast concrete piles
i'm looking into different options for my pre-cast piles.
one is by using pre-stressed concrete piles and the other is by conventional (using rebars only) reinforced concrete piles. both piles are designed to maintain the required capacity.
specifically, i would like to know:
a.)advantages and disadvantages between the two schemes.
b.) would the method of driving differ between the two schemes?
c.) would it be advantageous to use pre-stressed? in what way?
hope for your prompt reply. thanks.
check out our whitepaper library.
to the best of my knowledge, precast concrete piles (using only rebar) have been out of favor in the usa for over 50 years. driving equipment and techniques were the same as prestressed concrete piles. they were often cast, on the jobsite, by the project contractor, in forms that he had constructed. many times he even mixed his own concrete, on the jobsite, from the basic ingredients (sand, stone, cement & water).
by the 1950's better highways & larger trucks made delivery of prestressed products practical.
precast piles had a tendency to crack (no tension strands to "squeeze" the concrete together). of course this could allow water to enter to corrode the rebar.
one seldom used, but unique advantage of a precast pile, was the opportunity to include an axial steel pipe in the pile interior. then, in sandy soil, all the contractor had to do to jet the pile was to connect a pump to the pipe.

2009-09-15, 02:05 PM	#1
huangyhg 超级版主注册日期: 04-03 帖子: 18592 精华: 36 现金: 249466 标准币资产: 1080358888 标准币	pre-cast concrete piles pre-cast concrete piles i'm looking into different options for my pre-cast piles. one is by using pre-stressed concrete piles and the other is by conventional (using rebars only) reinforced concrete piles. both piles are designed to maintain the required capacity. specifically, i would like to know: a.)advantages and disadvantages between the two schemes. b.) would the method of driving differ between the two schemes? c.) would it be advantageous to use pre-stressed? in what way? hope for your prompt reply. thanks. check out our whitepaper library. to the best of my knowledge, precast concrete piles (using only rebar) have been out of favor in the usa for over 50 years. driving equipment and techniques were the same as prestressed concrete piles. they were often cast, on the jobsite, by the project contractor, in forms that he had constructed. many times he even mixed his own concrete, on the jobsite, from the basic ingredients (sand, stone, cement & water). by the 1950's better highways & larger trucks made delivery of prestressed products practical. precast piles had a tendency to crack (no tension strands to "squeeze" the concrete together). of course this could allow water to enter to corrode the rebar. one seldom used, but unique advantage of a precast pile, was the opportunity to include an axial steel pipe in the pile interior. then, in sandy soil, all the contractor had to do to jet the pile was to connect a pump to the pipe. __________________ 借用达朗贝尔的名言：前进吧，你会得到信心! [url="http://www.dimcax.com"]几何尺寸与公差标准[/url]