3210 36TH PL NE 2018-01-02 MF Import

TaGle 2. Ultimate Lateral Pile Capacity— 18-inch Augercast Pile Latoral Free Hoad Condition Fixed Head Candition � Deflectfon Lateral Load Maximum Bending Laterel Load Maximum Bending (in) (k�P) Moment(�n-kip) (kip) Moment(in-kip) ---__------------- -- _-- ------ __ . _ _ ____ Y. 10 650 30 2,000 - --------- -- �--- -...._.— -- y, p5 1,250 65 3,800 ---�------qg — --��—2,400 110 —�-- ---- 7.000 Sett/ement �Ve estimate that the post-conswclion settlemen[ of pile foundations, designed and installed as �- recommended, will be on the order of i, inch or less. Maximum differentiil sctdement should bc Icss than about one-half the post-construction settlemcnt. Most of this settlemcnt �vill occur rapidly as loads arc applicd. Construction Considerations �I The augercust piles should be installcd to thc recommended tip elcvatior.s using a continuous-(light. � hollow-stem augcr. 'I'he augercast piles gencrate cuttings as the soil is rcmo��ed. As is standard practice, the pile grout must be pumped under pressure through thc hollow stem as the auger is withdrawn. I Maintenance of adequate grout pressurc at the auger tip is critical [o reduce the potential for I encroachmenl of adjacent native soils into the grout column. 7�he rate ol withdrawal of Qie auger must remain constant throughout the installation of the pilcs in order to reduce the potential for necking of dic f piles. Pailum to maintain a constant rate of wididrawal of the auger will result in immediate rejection oC � that pile. Reinforcing steel for bcnding and uplift should be placed in thc &esh b�out column as soon as possible aEier wi[hd�awal of the augcr. Centering devices should be used to provide concrete co�cr Iaround thc reinforcing stcel. We recommend that there bc a �vaitinc p�riod of a[ Icast 12 hours benveen the installation of piles spaccd � closer than 8 feet, center-to-centcr. �Chis ��aiting periud is nccessmy m avoid disturbing the curi�g concre[e in previously cast piles. Grout pumps must be �itted �cith � �ulumc-mcasurin� dc�'iec and pressure �auge su that thc �ulumc of grout plaeed in eaeh pile and the pressure head maintain��l during pumping can be obserced. :� minimum grout line pressure of 100 pounds per square inch (psij should be maintained. The rate af augcr withdra�val should be cnnvolled during grouting such that the volume of grout pumpcd is cqual to at least 1 IS percent of the theorctical pile volume. A minimum head of l0 feet of grout should be maintained above the auger tip during withdr�wal of the auger to maintain a full column of grout and prevent holc col lapsc. We mcommend that the augercast piles be irstalled by a contracror experienced in their placement and using suitable equipment. To hclp moniG�r pile qualiry, we recommend diat the contractor be required to provide a pmssure gauge in the grout line behveen the pump and auger, and to provide a means of mcasuring the quantity of grout used in eadi pile (such as s stroke counter snd pump calibmtion j. 'Che action of the augcr may tend to disturb the soil at the 6ottorn of the drilled hole, which would result in decreased end-bearing capacity. In order to minimize the negati��e effects of tliis dis[urbance, ��c recommend that the pile contractor be reyuired to rotate die auger fo!lo�ving pumping of the first fe�c Fila No.8937-004-00 Paj�B 1 S GEOENG INEEB� e�r�nher 1/. 1006 ,�,. .-- -- „r t,�.� � . , . , " _ ,. `t {�jl., , _.I z d y ��.�, ,y �3,,� . .,�'h �_ � - } 1 ��r�L 1 � �.: y.��,�8`,+� ,� I �{ � E 9� � _',. `G.. �f p��' ...�: _ _ — _.— � .�_.. � _ ��, . ' � . i � ,{��i�sfiJ�/_:.. {kM1�!-��if� . Ti�.�,'�