将框架梁视为刚性梁,从而将锚索集中力转化为加在坡面上的矩形分布力,根据类土质边坡的工程特性,将边坡土体视为弹性体,推导了框架预应力锚索作用下坡体内任一点的预应力传递系数计算方法,得出了锚固预应力自坡面向坡体内的传递规律,并以G323改造工程某实际边坡为原型进行了离心模型试验,得出了预应力在坡体内不同位置处引起的土压力变化,问接得出预应力自坡面向坡体内的传递规律,离心模型试验得出的预应力传递规律与理论推导得出规律基本吻合。研究表明,在分布力作用下,类土质边坡岩土体的塑性形变相对于集中力作用时减小很多,坡体更多表现为弹性体,预应力分布系数受预应力大小的影响减小。相对于无框架单锚,框架预应力锚索措施中,锚索引起的高压应力得以很好的分散,压力分布系数由0.90左右降到了0.40左右,压应力集中程度减小约56%,从而在很大程度上减小了边坡浅层土体的压缩变形,减少了预应力损失,有效地提高了锚固效果,锚间距可由单锚的3.2m增大为4.2m左右。
On the assumption that the beams are rigid, and that the slope body is elastomeric, the anchoring concentrated force is translated into rectangular distributed force. And then, according the characters of soil-like slopes, the transferring equation of the prestressed force from slope surface into slope body in frame anchored soil-like slope is deduced. The transferring coefficients of the prestressed force are put forward according to the transferring formula. Some centrifugal model tests are carried out according to a granite soil-like slope locating at K617 of G232 national highway. In the centrifugal model tests, earth pressure cells are set at different points of the slope body to monitor the increased earth pressures caused by the prestressed force. And then the transferring discipline of the prestressed force from slope surface into slope body can be brought out. The results drawn out from centrifugal model tests agree with what from theoretical study mainly. The conclusions are drawn out from the calculations and model tests that the plastic deformation of the flame anchored slope body is distinctly small than single anchored slope body; and that the effect on distribution factor of prestressing force in frame anchored slope is smaller than what is in single anchored slope. The distribution factor of prestressing force is 0.4 in frame anchored slope, while it is 0.9 in single anchored slope, which indicates that about 56% of the prestressing force is well spread around. It is obvious that the compression strain in frame anchored slope is smaller than what is in single anchored slope, and that the decreasing of prestressing force can be smaller in frame anchored slope. The optimal space of anchors can enlarge to 4.2m for flame anchored slope from 3.2m in single anchored slope.