岩石力学与工程学报
巖石力學與工程學報
암석역학여공정학보
CHINESE JOURNAL OF ROCK MECHANICS AND ENGINEERING
2013年
z2期
4073-4081
,共9页
薛江炜%葛忻声%杨勇%蔡景珞
薛江煒%葛忻聲%楊勇%蔡景珞
설강위%갈흔성%양용%채경락
桩基础%桩伴侣%水平荷载%大直径管桩%低承台桩基%褥垫层
樁基礎%樁伴侶%水平荷載%大直徑管樁%低承檯樁基%褥墊層
장기출%장반려%수평하재%대직경관장%저승태장기%욕점층
pile foundations%pile partner%lateral load%large diameter pipe pile by using cast-in-place concrete(PCC)%pile foundation with low cap%pillow
借鉴现浇混凝土大直径管桩(PCC 桩)水平承载足尺试验和数值模拟的成果,建立水平荷载作用下多个构造形式有无伴侣的单桩有限元数值模型。对比计算与分析表明,对于低承台桩基设置桩伴侣可确保承台向地基土传递水平荷载,成倍减小基桩的应力和位移;对于桩身范围地基土模量低的低承台桩基的水平承载性状也有一定的改善;配备桩伴侣后,将桩与承台的连接方式由刚接改为铰接也能大幅度减小桩身内力,桩顶与承台的距离可单纯考虑竖向承载力和变刚度调平基础底板沉降的需要;设置桩伴侣后可取消褥垫层;桩伴侣的高度变化对水平荷载作用下桩内力和位移影响很小;在罕遇地震等荷载工况下,桩伴侣可作为耗能构件,首先牺牲伴侣,避免或延迟桩头的破坏。
藉鑒現澆混凝土大直徑管樁(PCC 樁)水平承載足呎試驗和數值模擬的成果,建立水平荷載作用下多箇構造形式有無伴侶的單樁有限元數值模型。對比計算與分析錶明,對于低承檯樁基設置樁伴侶可確保承檯嚮地基土傳遞水平荷載,成倍減小基樁的應力和位移;對于樁身範圍地基土模量低的低承檯樁基的水平承載性狀也有一定的改善;配備樁伴侶後,將樁與承檯的連接方式由剛接改為鉸接也能大幅度減小樁身內力,樁頂與承檯的距離可單純攷慮豎嚮承載力和變剛度調平基礎底闆沉降的需要;設置樁伴侶後可取消褥墊層;樁伴侶的高度變化對水平荷載作用下樁內力和位移影響很小;在罕遇地震等荷載工況下,樁伴侶可作為耗能構件,首先犧牲伴侶,避免或延遲樁頭的破壞。
차감현요혼응토대직경관장(PCC 장)수평승재족척시험화수치모의적성과,건립수평하재작용하다개구조형식유무반려적단장유한원수치모형。대비계산여분석표명,대우저승태장기설치장반려가학보승태향지기토전체수평하재,성배감소기장적응력화위이;대우장신범위지기토모량저적저승태장기적수평승재성상야유일정적개선;배비장반려후,장장여승태적련접방식유강접개위교접야능대폭도감소장신내력,장정여승태적거리가단순고필수향승재력화변강도조평기출저판침강적수요;설치장반려후가취소욕점층;장반려적고도변화대수평하재작용하장내력화위이영향흔소;재한우지진등하재공황하,장반려가작위모능구건,수선희생반려,피면혹연지장두적파배。
Reference on lateral load test and numerical simulation of large diameter pipe pile by using cast-in-place concrete(PCC),finite element model of a single pile with or without pile partner under lateral load is established. Comparison calculations show that pile partner can ensure lateral loads delivering from pile cap to foundation soil, and double reduce stress and displacement of pile. Pile partner can also make some improvement on lateral bearing characters for the pile foundation with low cap even though the modulus of foundation soil is small. When pile partner is equipped,and the connection mode between pile cap and pile changing from rigid connection to hinge joint,pile body internal force can also be drastically reduced;and pile and pile caps by distance can only be considered to meet the requirement of vertical bearing capacity or optimization design of pile foundation stiffness to reduce differential settlement. Pillow is not necessary and can be cancelled in composite foundation when pile partner is applied. The height of pile partner has little influence on internal force and displacement of pile. Under rare earthquake action,pile partner may sacrifice firstly to keep pile perform well.