發(fā)布時間：2018-01-31 23:47

  本文關(guān)鍵詞： 黏土 組合吸盤 黏附力 拉拔速率 含水率　出處：《巖土力學》2017年05期 　論文類型：期刊論文

【摘要】：座落于黏土地基上的結(jié)構(gòu)物在起浮或上拔過程中將受到地基對其的抗拉阻力。黏土對結(jié)構(gòu)的黏附力是地基抗拉阻力的組成部分,其值的選取對地基抗拔承載力的確定有重要的影響。為了研究黏附力的發(fā)展規(guī)律和影響因素,改進了組合測盤,將內(nèi)測盤底部和外界空氣相通,從而消除孔隙水壓力對黏附力的影響,并采用該測盤測量黏土在不同含水率、不同拉拔速率下的黏附力。試驗結(jié)果表明,黏土對基礎(chǔ)的拉拔應力隨著基礎(chǔ)拉拔位移的增加而線性增加,達到黏附力后將迅速消失。黏附力在含水率較小時為0,當土體的含水率超過塑限后黏附力開始增加,增加到峰值后下降,最后衰減到一個穩(wěn)定值。相同拉拔速率下含水率變化時黏附力的峰值隨拉拔速率的增加而增加,其對應的含水率隨拉拔速率的增加而降低。相同含水率下,黏附力隨拉拔速率的對數(shù)呈S型曲線變化。黏附力和土體不排水抗剪強度之間的比值隨含水率的增加而增加。以上研究結(jié)果為深入理解黏附力變化規(guī)律并指導工程實踐提供了依據(jù)。
[Abstract]:The structure located on the clay foundation will be subjected to the tensile resistance of the foundation during the process of floating or uplifting. The adhesion force of the clay to the structure is a part of the tensile resistance of the foundation. The selection of the value has an important impact on the determination of the uplift bearing capacity of the foundation. In order to study the law of the development of the adhesion force and the influencing factors, the combined test plate is improved, and the bottom of the inner test plate is connected with the outside air. Therefore, the influence of pore water pressure on adhesion force is eliminated, and the adhesion force of clay under different water content and different drawing rate is measured by using the plate. The drawing stress of clay to the foundation increases linearly with the increase of the drawing displacement of the foundation, and then disappears rapidly when the adhesion force is reached, and the adhesion force is 0 when the moisture content is small. When the soil moisture content exceeds the plastic limit, the adhesion force begins to increase, increases to the peak value and then decreases. The peak value of the adhesion force increases with the increase of the drawing rate, and the corresponding moisture content decreases with the increase of the drawing rate. The ratio between adhesion force and undrained shear strength of soil increases with the increase of moisture content. The above results are helpful to understand the change of adhesion force and guide the engineering. The practice of Cheng provides the basis.
【作者單位】： 天津大學建工學院巖土工程研究所;中水北方勘測設(shè)計研究有限責任公司;
【基金】：國家自然科學基金項目(No.41272323) 國家優(yōu)秀青年科學基金項目(No.51322904)~~
【分類號】：TU41
【正文快照】： 大量的海洋工程結(jié)構(gòu)物將承受上拔荷載,如何確定它們的地基抗拔承載力是工程設(shè)計、施工的關(guān)鍵。對于吸力錨、桶基、抗拔樁等工程,抗拔承載力是這些結(jié)構(gòu)物穩(wěn)定的重要保障;而對于自升式鉆井平臺、沉船打撈、拔樁等工程,抗拔承載力則是工程設(shè)計過程中需要克服的阻力。在抗拔承載力，

本文編號：1480321