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131" Street SW Bridge at 58"' Avenue
<br />File No. 07-5535
<br />Table 1: Abutment Pile Capacities
<br />-S»
<br />u4, '�i.'S Kw ir. 3�+
<br />4� iie`rWtdth
<br />t:, „i''pa;' .;s,
<br />���pnches]�^-'�,'•r:° 7�
<br />�,�.,'�iirir':. �:�;"<:)°�4�' "T'� 43'� }=a
<br />_ 4I en th,
<br />t:r-a r'a.;7?q i- y
<br />��',���.,[feetJ��:�����. �
<br />:y+:4 r.�•�:J.
<br />�i, :a.�'ru�i�.o-�,.�. .M hl"':1�v.
<br />Compression. Capaci
<br />�^ro''%• ,tt,�4 ;. :.i�d%'"-.�'�,.y
<br />� i��,.� tans �,,:a�r,,.
<br />�,i�.,�•G� �iN ]3•��"u".. �
<br />;�,f. J�QYYN,�n4'.a.'w "Y.11,'•�y'�}�-, r _
<br />' a
<br />t z �. �'°?''4 ,:".i�'y:'
<br />�,;����':r'��4[tons]��, �;-LL,
<br />j`r e+vY�k � ���A4 J"
<br />e1u7<;°9»4u'�I�l�4.�'I�wI�.,EF,�
<br />14
<br />40
<br />40
<br />20
<br />14
<br />45
<br />45
<br />25
<br />18
<br />40
<br />55
<br />25
<br />18
<br />45
<br />65
<br />40
<br />The above capacities include a factor of safety of 2, (i.e., the allowable compression capacities are
<br />half of the calculated Davisson capacities and the allowable tension (uplift) capacities are half of
<br />the calculated ultimate side friction).
<br />We recommend using published values for p -y multipliers (i.e., reduction factors) for the analyses
<br />of lateral capacity of pile groups. We recommend a minimum spacing of 5 feet (center -to -center)
<br />to provide a reasonable remnant of lateral pile capacity, and to promote the independent behavior
<br />of the individual piles in axial capacity.
<br />The lateral capacity of the piles will depend on the permitted lateral movement of the piles, the
<br />framing/bracing influence of the bridge superstructure, and the unsupported length of the pile. The
<br />piles can likely be considered to be fixed -head piles and restrained from rotation by the pile caps.
<br />Maximum bending moments and the location of the point of fixity will depend on the thicknesses
<br />of the pile caps, the reinforcing of the piles, etc. The Bridge Engineer should size the pile caps and
<br />reinforce the piles and pile caps so as to withstand all axial, bending, tensile, and shear stresses.
<br />Pile Installation
<br />Prestressed concrete piles should be driven with a variable energy hammer capable of delivering
<br />the energy specified in Florida Department of Transportation, Standard Specifications for Road and
<br />Bridge Construction, Section 455. Due to variable soil conditions, it may be necessary to vary the
<br />hammer energy during driving. Pile driving should be as continuous an operation as possible and
<br />should proceed without stopping over the last 10 feet of penetration.
<br />During driving, pile driving records should be kept for each pile detailing pertinent information such
<br />as the pile type, pile length, date driven, and blow count per foot. The capacity of each pile should
<br />be reviewed based on its final tip elevation and driving record. We recommend that pile driving
<br />operations be continuously monitored by an Ardaman representative.
<br />We recommend using a Pile Driving Analyzer (PDA) on at least one test pile to verify the capacities
<br />of these piles. Pending the results of the PDA, the test pile can be used as a production pile. Care
<br />should be exercised when selecting the hammer type and energy rating so as to avoid damaging
<br />the piles during the installation process.
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