基于GRLWEAP的桩基可打入性影响因素研究

Study of factors influencing pile foundation driveability based on GRLWEAP

桩基的可打入性分析对桩的设计十分重要。实际工程中精确的可打入性分析可以避免由于未能将桩打入设计入土深度而导致的截桩和桩头损坏等事故,也能避免在桩的贯入深度已经超过设计贯入深度时仍不能满足设计承载力的情况发生。为精确桩基的可打入性分析,研究了影响桩基可打入性的多种敏感因素,采用正交实验法设计了32组试验,由GRLWEAP软件完成试验,得出打桩分析结果。结合渤海某油田平台工程实例得出桩基可打入性影响因素敏感度规律,即桩基可打入性影响因素敏感度由大到小依次是打桩能量、桩径、地质条件、桩长、垫层厚度、桩壁厚、停锤时间、停锤位置、桩段数量。

Pile foundation driveability analysis is very important for pile design. In actual projects, precise pile driveability analyses would prevent the pile from being cut off or damaged when the pile couldn't drive into the given depth, and could also keep pile bearing capacity not less than design capacity when penetration depth is deeper than the design depth. In order to analyze the pile foundation driveability accurately, this paper studies the sensitive factors which could affect pile foundation driveability analysis. 32 experiments are designed with orthogonal experiment and completed by GRLWEAP; the pile driving analysis results are obtained afterwards. Through the case study of Bohai sea oil field platform project, same conclusions can be drawn on the sensitivity regularity of pile foundation driveability influencing factors. The sensitivity of the factors that influencing pile foundation drivability from large to small is in this particular order: piling energy, geological conditions, pile diameter, pile length, cushion thickness, pile wall thickness, stop-driving time, stop-driving location and the pile section numbers.