高速铁路技术
高速鐵路技術
고속철로기술
HIGH SPEED RAILWAY TECHNOLOGY
2014年
1期
42-49
,共8页
桩承式路堤%梅花形布桩%土拱效应%桩土应力比%桩体荷载分担比
樁承式路隄%梅花形佈樁%土拱效應%樁土應力比%樁體荷載分擔比
장승식로제%매화형포장%토공효응%장토응력비%장체하재분담비
pile-supported embankment%quincunx-shape layout of piles%soil arch effect%pile-soil stress ratio%pile effi-cacy
推导了梅花形布桩的土拱效应计算方法，得到了桩体荷载分担比和桩土应力比表达式。研究了填料内摩擦角、路堤高度、桩径与桩间距比值对正方形布桩和梅花形布桩路堤竖向应力分布、桩体荷载分担比和桩土应力比的影响。研究表明：正方形布桩和梅花形布桩的路堤竖向应力变化特征相似，但正方形布桩时土拱高度大于梅花形布桩，二者之差约为13％；土拱发展可分成未形成土拱、土拱发育状态及塑性状态3种状态；路堤形成土拱的临界高度正方形布桩时为0.8倍净桩间距，梅花形布桩时为0.7倍净桩间距；填料内摩擦角越大，桩间距越小，土拱塑性状态的路堤临界高度越高。填料内摩擦角为25°～45°，梅花形布桩时，采用Hewlett法计算，结果将比文中提出的计算方法小2.6％～8.2％。
推導瞭梅花形佈樁的土拱效應計算方法，得到瞭樁體荷載分擔比和樁土應力比錶達式。研究瞭填料內摩抆角、路隄高度、樁徑與樁間距比值對正方形佈樁和梅花形佈樁路隄豎嚮應力分佈、樁體荷載分擔比和樁土應力比的影響。研究錶明：正方形佈樁和梅花形佈樁的路隄豎嚮應力變化特徵相似，但正方形佈樁時土拱高度大于梅花形佈樁，二者之差約為13％；土拱髮展可分成未形成土拱、土拱髮育狀態及塑性狀態3種狀態；路隄形成土拱的臨界高度正方形佈樁時為0.8倍淨樁間距，梅花形佈樁時為0.7倍淨樁間距；填料內摩抆角越大，樁間距越小，土拱塑性狀態的路隄臨界高度越高。填料內摩抆角為25°～45°，梅花形佈樁時，採用Hewlett法計算，結果將比文中提齣的計算方法小2.6％～8.2％。
추도료매화형포장적토공효응계산방법，득도료장체하재분담비화장토응력비표체식。연구료전료내마찰각、로제고도、장경여장간거비치대정방형포장화매화형포장로제수향응력분포、장체하재분담비화장토응력비적영향。연구표명：정방형포장화매화형포장적로제수향응력변화특정상사，단정방형포장시토공고도대우매화형포장，이자지차약위13％；토공발전가분성미형성토공、토공발육상태급소성상태3충상태；로제형성토공적림계고도정방형포장시위0.8배정장간거，매화형포장시위0.7배정장간거；전료내마찰각월대，장간거월소，토공소성상태적로제림계고도월고。전료내마찰각위25°～45°，매화형포장시，채용Hewlett법계산，결과장비문중제출적계산방법소2.6％～8.2％。
In this paper,a new calculation method for soil arch effect of piles with quincunx-shape layout is derived and formulas of pile efficacy and pile-soil stress ratio are obtained.The influence of internal friction angle of filling,height of embankment,ratio of pile diameter and pile spacing on vertical stress distribution,pile efficacy and pile-soil stress ratio of pile-supported embankment with square layout and quincunx-shape layout are analyzed.Research results show that pile-supported embankment with square-shape layout is similar to pile embankment with quincunx-shape layout in verti-cal stress changing characteristics.But the height of soil arch with square-shape layout is 13% more than that of soil arch with quincunx-shape layout.The development of soil arch can be divided into undeveloped state,developed state and plastic state.The critical height of soil arch formed in pile-supported embankment with square-shape layout is 0.8 times of net spacing between piles and for quincunx-shape layout,0.7 times of net spacing between piles.The greater the Angle of internal friction of filling is,the smaller of the pile spacing,the higher the critical height of embankment of the soil arch plastic state.If internal friction angle of filling is 25 °~45 °and layout of pile is quincunx,the calculation results with Hewlett's method is 2.6~8.2 % smaller than that with the method in the paper.
