CAJ | 학술논문

对基坑倾斜坡面的主动土压力计算方法、桩锚支护结构的锚杆水平弹簧系数的计算方法以及桩锚支护结构计算主动土压力应否考虑桩、土间的摩擦力等存在异议的问题进行理论分析和简化计算公式的推导,提出基坑倾斜坡面的主动土压力、桩锚支护结构的锚杆水平弹簧系数和考虑桩、土间的摩擦力的主动土压力计算公式.基坑倾斜坡面的主动土压力可以直接采用建立在极限平衡理论基础之上的计算公式计算,而无需采用先计算朗肯主动土压力再进行修正的计算方法.桩锚支护结构中的锚杆头部一般不可能发生竖向位移,可假定锚杆轴向伸长量等同水平伸长量,以此假定计算锚杆水平弹簧系数比较合理.用算例对所推导的计算公式和现行规程的计算公式进行计算比较,工程现象及算例结果均表明,不管是土钉墙还是桩锚支护结构,现行规程土压力计算公式未考虑墙(桩)、土间的摩擦力,计算的主动土压力偏大;现行规程计算的桩锚支护结构的锚杆水平弹簧系数偏小.因此,设计的支护结构均偏安全,不利于控制工程成本,应根据工程实际情况进行适当优化.
대기갱경사파면적주동토압력계산방법、장묘지호결구적묘간수평탄황계수적계산방법이급장묘지호결구계산주동토압력응부고필장、토간적마찰력등존재이의적문제진행이론분석화간화계산공식적추도,제출기갱경사파면적주동토압력、장묘지호결구적묘간수평탄황계수화고필장、토간적마찰력적주동토압력계산공식.기갱경사파면적주동토압력가이직접채용건립재겁한평형이론기출지상적계산공식계산,이무수채용선계산랑긍주동토압력재진행수정적계산방법.장묘지호결구중적묘간두부일반불가능발생수향위이,가가정묘간축향신장량등동수평신장량,이차가정계산묘간수평탄황계수비교합리.용산례대소추도적계산공식화현행규정적계산공식진행계산비교,공정현상급산례결과균표명,불관시토정장환시장묘지호결구,현행규정토압력계산공식미고필장(장)、토간적마찰력,계산적주동토압력편대;현행규정계산적장묘지호결구적묘간수평탄황계수편소.인차,설계적지호결구균편안전,불리우공제공정성본,응근거공정실제정황진행괄당우화.
The problems for calculational methods of active earth pressure of inclined excavation slope plane and the horizontal anchor spring coefficient of pile-anchor retaining and protection structure,and whether considering the friction between pile and soil or not on calculating active earth pressure are discussed,and these calculation formulas are deduced. The active earth pressure of inclined excavation slope plane can be directly calculated using the formula on the limit-equilibrium theory,no need first to calculate the Rankine's active earth pressure and then amend the result. The vertical displacement of pile-anchor retaining and protection structure generally does not occur to anchored bearing,so the axis extension of anchor is assumed equal to the horizontal extension of anchor,and it is rational to calculate the horizontal anchor spring coefficient on this assumption. The deduced formulas are compared with the formulas in code by calculation examples. Both engineering case and the calculating results of the examples show that the calculating active earth pressure using the formula in code is more than the calculating active earth pressure without considering the friction between pile and soil,and the calculating horizontal anchor spring coefficient using the formula in code is smaller than the calculating result using the formula for whether soil-nail wall or pile-anchor retaining and protection structure. Therefore,the retaining and protection structure of excavation should be properly optimized for the purpose of controlling engineering cost.