砂土中靜壓管樁樁周土壓力及承載特性的模型試驗(yàn)研究
發(fā)布時(shí)間：2018-11-26 19:50
【摘要】：靜壓樁具有施工速度快,無(wú)污染、噪音低、無(wú)振動(dòng)、無(wú)沖擊力等許多優(yōu)點(diǎn),因此用途比較廣泛,尤其是在軟土等地基中。靜壓樁屬于擠土樁,在貫入過程中受到土體擠壓,單樁產(chǎn)生樁-土相互作用,從而周圍土體的密實(shí)度發(fā)生變化,進(jìn)而樁周土壓力會(huì)相應(yīng)的改變;沉樁完成后隨著時(shí)間的增加,由于土體的自穩(wěn)和重塑,承載力會(huì)相應(yīng)的提高。因此,能有效預(yù)估靜壓樁產(chǎn)生的擠土效應(yīng)、探究它的周圍土體應(yīng)力變化以及自身的承載特性,對(duì)工程具有很大意義。本文首先對(duì)靜壓樁的沉樁受力特性和承載力特性結(jié)合國(guó)內(nèi)外研究現(xiàn)狀進(jìn)行了總結(jié),本文著重對(duì)如下內(nèi)容進(jìn)行了研究:(1)對(duì)兩種樁身承載力理論計(jì)算進(jìn)行了詳細(xì)的推導(dǎo),包括基于球孔擴(kuò)張理論樁端承載力的比較和經(jīng)典的樁基礎(chǔ)地基承載力公式進(jìn)行了說(shuō)明。推導(dǎo)出靜壓樁貫入土體過程中樁身法向應(yīng)力、徑向應(yīng)力、和塑性區(qū)位移的一般解;給出了塑性區(qū)的平均體積應(yīng)的一般解;在沉樁終壓力的基礎(chǔ)上給出了樁端承載力的公式,應(yīng)用此公式可對(duì)樁端承載力進(jìn)行預(yù)測(cè),并介紹了兩種樁基礎(chǔ)承載力的經(jīng)典公式。(2)為探究樁土相互作用的大小,需要測(cè)得樁土界面的土壓力,為此提出了三種測(cè)土壓力的方法:薄膜壓力傳感器、土壓力盒、懸臂式土壓力測(cè)量裝置,對(duì)于三種測(cè)量方法進(jìn)行了室內(nèi)標(biāo)定試驗(yàn)。懸臂式土壓力測(cè)量裝置可以減小土拱效應(yīng),在模型樁試驗(yàn)中,土壓力盒的優(yōu)點(diǎn)比較突出,薄膜壓力傳感器有待于進(jìn)一步研究。(3)基于原有的靜壓樁豎向加載系統(tǒng),改進(jìn)了設(shè)備,通過滑板代替原有的滑桿提高壓樁過程中壓樁系統(tǒng)的剛度,使模型樁貫入過程中的垂直精度進(jìn)一步提高。采用PLC伺服電動(dòng)缸控制,實(shí)現(xiàn)自動(dòng)、穩(wěn)定和精確加載。自主研發(fā)了一種多功能模型試驗(yàn)樁,該模型樁通過內(nèi)嵌土壓力盒及其樁端設(shè)置力傳感器,能夠精確測(cè)量出樁土界面的土壓力大小及其樁端阻力的大小。(4)在模型箱中進(jìn)行靜壓樁貫入過程及靜載的試驗(yàn),探究在不同沉樁速度完成后,測(cè)得的各個(gè)樁深處的土壓力大小,以及貫入過程中樁側(cè)摩阻力、樁端阻力、壓樁力以及樁端殘余應(yīng)力的變化規(guī)律。通過靜載試驗(yàn)探究單一砂土中靜壓?jiǎn)螛兜某休d特性及規(guī)律。對(duì)本文試驗(yàn)得到的結(jié)果與承載力理論計(jì)算方法進(jìn)行了比較,探究它們之間的相互關(guān)系與區(qū)別。
[Abstract]:Static pressure pile has many advantages, such as fast construction speed, no pollution, low noise, no vibration, no impact force and so on, so it is widely used, especially in soft soil foundation. Static pressure pile is a kind of compaction pile, which is squeezed by soil in the process of penetration, the pile-soil interaction is produced by single pile, so the compactness of surrounding soil changes, and the soil pressure around pile will change accordingly. With the increase of time, the bearing capacity of the pile will be increased due to the self-stability and remolding of the soil. Therefore, it is of great significance for engineering to estimate the squeezing effect of static pressure pile effectively, to explore the stress change of soil around it and its bearing characteristics. In this paper, the mechanical characteristics and bearing capacity characteristics of static pressure pile are summarized firstly. The main contents of this paper are as follows: (1) the theoretical calculation of bearing capacity of two kinds of piles is deduced in detail. The comparison of pile end bearing capacity based on spherical hole expansion theory and the classical formula of pile foundation bearing capacity are presented. The general solutions of normal stress, radial stress and plastic region displacement of the pile body during the penetration of static pressure pile into soil are derived, and the general solution of the average volume response of plastic zone is given. Based on the ultimate pressure of pile-sinking, the formula of pile-end bearing capacity is given, which can be used to predict the pile-end bearing capacity, and two classical formulas of pile-foundation bearing capacity are introduced. (2) in order to explore the magnitude of pile-soil interaction, It is necessary to measure the earth pressure at the pile-soil interface. For this reason, three methods of measuring the earth pressure are put forward: the thin film pressure sensor, the earth pressure box and the cantilever earth pressure measuring device, and the indoor calibration tests are carried out for the three measuring methods. The cantilever earth pressure measuring device can reduce the soil arch effect. In the model pile test, the advantages of the earth pressure box are outstanding, and the membrane pressure sensor needs further study. (3) based on the original vertical loading system of static pressure pile, The equipment is improved, and the stiffness of the pile-pressing system is improved by replacing the original slider with the slide plate, so that the vertical precision of the model pile in the process of penetration is further improved. PLC servo electric cylinder control is used to realize automatic, stable and accurate loading. A multi-function model test pile is developed. The model pile is set up through the pressure box and the end of the pile. It can accurately measure the soil pressure at the pile-soil interface and the resistance at the end of the pile. (4) the static pressure pile penetration process and static load test are carried out in the model box. The soil pressure of each pile is measured, and the variation law of pile side friction, pile tip resistance, pile-pressing force and residual stress in the process of penetration is obtained. The bearing characteristics and law of static pressure single pile in single sand are studied by static load test. The results obtained in this paper are compared with the theoretical calculation method of bearing capacity, and the relationship and difference between them are explored.
【學(xué)位授予單位】：河南工業(yè)大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TU473.1
本文編號(hào)：2359465
[Abstract]:Static pressure pile has many advantages, such as fast construction speed, no pollution, low noise, no vibration, no impact force and so on, so it is widely used, especially in soft soil foundation. Static pressure pile is a kind of compaction pile, which is squeezed by soil in the process of penetration, the pile-soil interaction is produced by single pile, so the compactness of surrounding soil changes, and the soil pressure around pile will change accordingly. With the increase of time, the bearing capacity of the pile will be increased due to the self-stability and remolding of the soil. Therefore, it is of great significance for engineering to estimate the squeezing effect of static pressure pile effectively, to explore the stress change of soil around it and its bearing characteristics. In this paper, the mechanical characteristics and bearing capacity characteristics of static pressure pile are summarized firstly. The main contents of this paper are as follows: (1) the theoretical calculation of bearing capacity of two kinds of piles is deduced in detail. The comparison of pile end bearing capacity based on spherical hole expansion theory and the classical formula of pile foundation bearing capacity are presented. The general solutions of normal stress, radial stress and plastic region displacement of the pile body during the penetration of static pressure pile into soil are derived, and the general solution of the average volume response of plastic zone is given. Based on the ultimate pressure of pile-sinking, the formula of pile-end bearing capacity is given, which can be used to predict the pile-end bearing capacity, and two classical formulas of pile-foundation bearing capacity are introduced. (2) in order to explore the magnitude of pile-soil interaction, It is necessary to measure the earth pressure at the pile-soil interface. For this reason, three methods of measuring the earth pressure are put forward: the thin film pressure sensor, the earth pressure box and the cantilever earth pressure measuring device, and the indoor calibration tests are carried out for the three measuring methods. The cantilever earth pressure measuring device can reduce the soil arch effect. In the model pile test, the advantages of the earth pressure box are outstanding, and the membrane pressure sensor needs further study. (3) based on the original vertical loading system of static pressure pile, The equipment is improved, and the stiffness of the pile-pressing system is improved by replacing the original slider with the slide plate, so that the vertical precision of the model pile in the process of penetration is further improved. PLC servo electric cylinder control is used to realize automatic, stable and accurate loading. A multi-function model test pile is developed. The model pile is set up through the pressure box and the end of the pile. It can accurately measure the soil pressure at the pile-soil interface and the resistance at the end of the pile. (4) the static pressure pile penetration process and static load test are carried out in the model box. The soil pressure of each pile is measured, and the variation law of pile side friction, pile tip resistance, pile-pressing force and residual stress in the process of penetration is obtained. The bearing characteristics and law of static pressure single pile in single sand are studied by static load test. The results obtained in this paper are compared with the theoretical calculation method of bearing capacity, and the relationship and difference between them are explored.
【學(xué)位授予單位】：河南工業(yè)大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TU473.1
【參考文獻(xiàn)】
相關(guān)期刊論文 前10條
1 呂清顯;肖昭然;朱亮亮;蔣敏敏;曹明明;趙憲強(qiáng);;砂土中靜壓管樁在不同沉樁速度下的模型試驗(yàn)研究[J];科學(xué)技術(shù)與工程;2016年24期
2 周航;孔綱強(qiáng);劉漢龍;;飽和土體中橢圓孔擴(kuò)張彈塑性解[J];巖土工程學(xué)報(bào);2014年05期
3 李富榮;張艷梅;王照宇;;軟土中靜壓樁擠土效應(yīng)的模型試驗(yàn)研究[J];建筑科學(xué);2013年01期
4 寇海磊;張明義;張吉坤;;層狀粘性土及砂土地基中靜力壓樁連續(xù)貫入的數(shù)值模擬[J];工程力學(xué);2012年12期
5 肖昭然;劉軼;;靜力沉樁的室內(nèi)模型試驗(yàn)裝置研發(fā)[J];巖土工程學(xué)報(bào);2012年09期
6 蔣明鏡;孫渝剛;;考慮砂土顆粒破碎的圓孔擴(kuò)張半解析分析[J];巖土工程學(xué)報(bào);2009年11期
7 周健;鄧益兵;葉建忠;賈敏才;;砂土中靜壓樁沉樁過程試驗(yàn)研究與顆粒流模擬[J];巖土工程學(xué)報(bào);2009年04期
8 徐光明;陳愛忠;曾友金;顧行文;蔡正銀;;超重力場(chǎng)中界面土壓力的測(cè)量[J];巖土力學(xué);2007年12期
9 蔣躍楠;韓選江;;靜壓樁終壓力及單樁豎向承載力的相關(guān)性[J];南京工業(yè)大學(xué)學(xué)報(bào)(自然科學(xué)版);2006年05期
10 李鏡培;王勇剛;;嵌巖樁樁端承載力探討[J];力學(xué)季刊;2006年01期
相關(guān)博士學(xué)位論文 前5條
1 鄭華茂;砂土中靜壓管樁模型試驗(yàn)及受力性能研究[D];鄭州大學(xué);2015年
2 劉俊偉;靜壓開口混凝土管樁施工效應(yīng)試驗(yàn)及理論研究[D];浙江大學(xué);2012年
3 朱寧;靜力壓樁引起樁周土體變形的理論分析[D];河海大學(xué);2005年
4 羅戰(zhàn)友;靜壓樁擠土效應(yīng)及施工措施研究[D];浙江大學(xué);2004年
5 李月健;土體內(nèi)球形空穴擴(kuò)張及擠土樁沉樁機(jī)理研究[D];浙江大學(xué);2001年
相關(guān)碩士學(xué)位論文 前1條
1 朱亮亮;砂土中靜壓樁貫入過程樁身應(yīng)力變化模型試驗(yàn)研究[D];河南工業(yè)大學(xué);2015年
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