本文選題：橋梁工程 + PHC管樁��； 參考：《中國公路學報》2017年10期

【摘要】：為了解沿海軟土地區(qū)PHC管樁在地震作用下的動力反應(yīng)、樁-土動力相互作用特性以及破壞模式,開展PHC管樁-土-結(jié)構(gòu)模型體系的地震模擬振動臺試驗研究。通過輸入3種不同地震波,并逐漸增加地震波峰值,研究預(yù)應(yīng)力度、土體特性對模型體系的地震響應(yīng)與破壞模式的影響。研究結(jié)果表明:土體飽和與否對模型體系的動力特性和地震響應(yīng)影響較大,PHC管樁的預(yù)應(yīng)力對其動力特性有一定影響,破壞模式也不相同;土體未飽和時,基本烈度地震作用下PHC管樁的一階頻率下降不大,土體飽和時,隨著地震波激勵的增加,模型體系的自振頻率逐漸下降、阻尼比逐漸增大,PHC管樁-土-結(jié)構(gòu)間的相互作用加大,結(jié)構(gòu)開始損傷破壞,頻率最大下降至初始頻率的50%;預(yù)應(yīng)力的存在可較顯著地減緩地震作用下結(jié)構(gòu)的損傷破壞;加速度峰值越大或者土體越深,孔壓比越大,最大超過1.0,并出現(xiàn)液化現(xiàn)象,且液化持續(xù)時間遠大于地震波持時。研究結(jié)果可為沿海軟土地區(qū)PHC管樁的應(yīng)用和規(guī)范的制定提供參考。
[Abstract]:In order to understand the dynamic response, pile-soil dynamic interaction and failure mode of PHC pipe pile in coastal soft soil area, the shaking table test of PHC pipe pile-soil-structure model system was carried out. By inputting three kinds of different seismic waves and increasing the peak value of seismic wave gradually, the influence of prestress degree and soil characteristics on the seismic response and failure mode of the model system is studied. The results show that whether the soil is saturated or not has a great influence on the dynamic characteristics and seismic response of the model system. The prestress of PHC pipe pile has a certain influence on its dynamic characteristics, and the failure mode is also different, and when the soil is not saturated, The first order frequency of PHC pipe pile decreases little under the action of basic earthquake intensity. When the soil is saturated, the natural vibration frequency of the model system decreases gradually with the increase of seismic wave excitation, and the damping ratio increases gradually, and the interaction between the pipe pile and soil-structure increases with the increase of damping ratio. The structure begins to damage, the maximum frequency decreases to 50% of the initial frequency; the existence of prestress can significantly slow down the damage and damage of the structure under earthquake; the larger the acceleration peak value or the deeper the soil, the greater the pore pressure ratio. The maximum is more than 1.0, and liquefaction occurs, and the duration of liquefaction is much longer than that of seismic wave. The results can be used as a reference for the application of PHC pipe piles and the formulation of specifications in coastal soft soil areas.
【作者單位】： 福州大學土木工程學院;福建建筑科學研究院;
【基金】：國家自然科學基金項目(51578161,51278126)
【分類號】：U443.1;U446.1
，

本文編號：1912082