- 摘 要
-
(中南大學土木工程學院， 長沙 410075)
［摘要］為研究增強型預應力管樁的豎向承載特性，將其縱向凸肋按截面積計入樁體剛度，而環(huán)向凸肋對樁側土的作用通過樁肋側阻提高系數(shù)來反映；基于雙曲線模型的荷載傳遞法，對外徑相同的普通光圓型預應力管樁與增強型預應力管樁的模擬計算結果和現(xiàn)場靜載荷試驗結果進行對比分析，并采用該方法分析了環(huán)向凸肋部外徑、環(huán)向凸肋間距和環(huán)向凸肋下部寬度等樁型參數(shù)對增強型預應力管樁荷載沉降曲線的影響。結果表明：計算得到的增強型預應力管樁的極限承載力值和沉降值與實測值均比較接近，普通光圓型預應力管樁計算的極限承載力值較接近實測值，但沉降值較實測值偏小。為獲得較好的承載性能，環(huán)向凸肋厚t與樁體外徑Dp的比值應控制在0.15～0.2；環(huán)向凸肋間距Lw應不大于1.5m；環(huán)向凸肋下部寬度L3w應不大于4t。
［關鍵詞］增強型預應力管樁; 荷載傳遞法; 荷載-沉降曲線; 承載性能; 樁型參數(shù)
中圖分類號：TU473 文獻標識碼：A 文章編號：1002-848X(2014)01-0077-05
Load-settlement behavior and simulation analysis of enhanced prestressed pipe piles
Guo Zhiguang, Wei Limin, Feng Shengyang, He Qun
(School of Civil Engineering, Central South University, Changsha 410075, China)
Abstract: To investigate vertical bearing characteristics of enhanced prestressed pipe piles, longitudinal ribs were considered to improve pile stiffness by including the cross-sectional area of the pile and the effect of circumferential ribs on soil can be reflected by friction improving coefficient. Based on the hyperbolic model load transfer method, the comparison between the in-situ static load test of the enhanced prestressed pipe pile with rib and the common circular pipe pile with the same outer diameter was made and the influence of the pile parameters (including the diameter of the rib, the spacing between ribs and the width of rib lower side) on the load-settlement curve of enhanced prestressed pipe piles was studied. The results show that calculated ultimate bearing capacity and settlement of enhanced prestressed pipe piles are close to that measured. Calculated ultimate bearing capacity of the circular pipe pile is close to that measured but settlement is a little smaller. For greater bearing capacity and smaller settlement, it is suggested that the ratio of rib thickness t to outer diameter Dp should be controlled between 0.15 and 0.2 and rib spacing Lw should not exceed 1.5m. Moreover, ribbed bottom width L3w should not be larger than 4t.
Keywords: enhanced prestressed pipe pile; load transfer method; load-settlement curve; bearing capacity; pile parameter
*鐵道部科技研究開發(fā)計劃重點課題(2009G008-B，2010G018-E-3)。
作者簡介：郭志廣，博士研究生，Email：guo009@foxmail.com。
參考文獻
［1］沈保漢，賀德新，陳輪，等. DX多節(jié)擠擴灌注樁［J］. 巖土工程界, 2002, 5(4): 30-35.
［2］錢德玲. 支盤樁地基相互作用及有限元法模擬的研究［J］. 土木工程學報, 2004, 37(2): 82-86.
［3］黃敏，龔曉南. 一種帶翼板預應力管樁及其性能初步研究［J］. 土木工程學報, 2005，38(5): 59-62.
［4］史玉良. 預制節(jié)樁的荷載試驗及荷載傳遞性能分析［J］. 工業(yè)建筑, 1993, 23(7): 3-9.
［5］小椋仁志，山肩邦男，岸田英明.模型実驗による節(jié)付き円筒杭の支持力特性の検討［R］//日本建築學會構造系論文報告集.第374號昭和62年4月，87-97.
［6］XU YOUZAI, YABUUCHI S. Bearing capacity of precast nodular piles in Tianjin soft clayey soil［C］//Proceedings of the 4th International Conference on Piling and Deep Foundations. Stresa, 1991.
［7］熊厚仁，蔣元海，楊建永，等. 新型帶肋預應力管樁承載特性試驗研究［J］. 混凝土與水泥制品, 2009(2): 32-35.
［8］熊厚仁，蔣元海，牛志榮，等. 豎向荷載下新型帶肋預應力管樁數(shù)值模擬研究［J］. 建筑結構, 2010, 40(10): 107-109.
［9］肖宏彬，鐘輝虹，張亦靜，等. 單樁荷載沉降關系的數(shù)值模擬方法［J］. 巖土力學, 2002, 23(5): 592-596.
