基于二次回归法的充气锚杆锚固特性影响因素分析

为了明确影响充气锚杆锚固特性的因素及因素间的交互影响,采用二次正交回归组合设计法,以抗拔承载力和位移作为评价指标,对充气锚杆埋深、气囊压力、土层含水率进行试验,并用响应面法进一步验证。结果表明:对充气锚杆极限抗拔承载力和极限位移产生影响的因素中,埋深的影响最大,但非越深越好,原因在于土压力过大时,形成的气囊较小,从而影响锚固效果;充气压力的影响次之,总体上随着充气压力的增大而增大;土体含水率的影响最小,通过对数据的分析,可以得出含水率的增加,会降低充气锚杆的锚固作用,但数据差异小,所以含水率起次要作用;埋深和充气压力的交互作用最为显著,充气压力与含水率组大于埋深与充气压力组产生的交互作用。

Factors Analysis on Anchorage Characteristics of Inflatable Anchor Based on Quadratic Regression Orthogonal Test

In order to determine the factors that influence the anchoring characteristics of inflatable anchor, and the interaction between factors, a quadratic orthogonal regression combination design method was proposed. Using the pull-out capacity and displacement as the evaluation index, the experiment was carried out on the depth of the inflatable anchor, the inflating pressure and the moisture content of the soil layer. Finally the response surface method was further verified. The results show that: the depth of the inflatable anchor is the most important factor ,but the deeper the better. The reason is that when the earth pressure is too large, the formation of the airbag is small, thus affecting the anchoring effect. The influence of inflating pressure is secondary. In general, with the increase of inflating pressure, the evaluation index increases. The influence of soil moisture content is the least. Through the analysis of data, it concluded that the increase of moisture content reduces the anchoring effect, but the difference is small. It can be seen that the moisture content plays a minor role in the anchoring of inflatable anchor.The interaction between the buried depth and the inflating pressure is the most significant, and the interaction between the inflating pressure and the moisture content is greater than the interaction between the buried depth and the inflating pressure.