Settlement calculation method of combined grouted bored piles considering influence of length-diameter ratio
The length-diameter ratio has important influences on the bearing behavior of combined grouting bored piles.Based on the field test data of bored piles in the Jinghang Grand Canal Bridge on Ningliang Expressway,the effects of combined grouting,length-diameter ratio and bearing layer on the load transfer characteristics of bored piles were analyzed.On this basis,the calculation method for settlement for combined grouting bored piles based on the load transfer method and spherical permeation grouting theory was established,considering the influences of length-diameter ratio and an enlarged pile tip,and the rationality of the calculation method was varified by an engineering example.The results show that combined grouting effectively improves the ultimate bearing capacity of bored piles under the premise of pile length optimization.The load transfer characteristics of the combined grouting bored pile are greatly affected by the length-diameter ratio and the type of bearing layer.The initial slope of the side load transfer curve of the combined grouting bored pile with different length-diameter ratios can vary by up to 380％.Compared with existing prediction methods,the proposed calculation method can better predict the actual load-settlement characteristics of the combined grouting bored pile,which provides a reference for the scientific optimization and design of the combined grouting bored pile while ensuring the safety of the prediction results.
万方数据
维普
