石河子机场强夯及碾压试验区地基处理效果分析

发布时间：2018-01-18 07:03

本文关键词：石河子机场强夯及碾压试验区地基处理效果分析　出处：《新疆农业大学》2015年硕士论文　论文类型：学位论文

【摘要】：本文以石河子机场强夯及碾压实验区地基处理为实例,研究强夯法及碾压法在本工程中各种工况下的技术参数并分析处理效果。强夯法是一种十分经济并且简便的地基加固方法,采用强夯法加固地基,加固效果明显,施工十分简单,而且经济实用。场地地基土在强夯影响深度范围内主要为粉质粘土,其地质条件适合强夯法进行地基处理,且场地位于郊外,场地空旷,具备强夯施工的外部条件。使用强夯法进行地基加固。能量主要消耗在垂直方向上,所以对低液限粘土的加固效果非常明显,土体各项指标的提高效果明显。场地夯前湿陷系数(δs)大于0.015,为湿陷性黄土。使用强夯法加固后,湿陷系数(δs)在0-3m范围内基本小于了0.015,消除了湿陷性。强夯能级在1000 k N·m、2000 k N·m和3000 k N·m,随着强夯能级的增加,加固深度也有明显增加,而当强夯能级达到6000k N·m后,对上层0-5m的湿陷性可以达到全部消除,对于5m以下的范围,湿陷性为部分消除,有些由强湿陷性转为中等湿陷,影响深度没有很明显的增加。强夯能级6000k N·m和4000k N·m的场地密实度,干密度,含水率、压缩系数和湿陷系数比3000k N·m、2000k N·m和1000k N·m的16块场地强夯后变化更加明显。通过载荷试验数据得出,通过强夯法处理地基后,静荷载试验得到的数据显示场地的湿陷性基本消除,符合强夯处理效果的判断标准。6000k N·m强夯能级加固的在0-5m的渗透系数变化非常明显,5-6.2m的渗透系数变化不明显,4000k N·m强夯能级加固的在0-3m的渗透系数变化非常明显,3-4.2m的渗透系数变化不明显,这说明6000k N·m强夯能级的影响深度为5m,4000k N·m强夯能级的影响深度为3m。这也说明6000k N·m强夯能级对于湿陷性消除的深度为5m,4000k N·m强夯能级对于湿陷性消除的深度为3m。在处理深度范围内渗透系数明显降低,加固效果十分显著,满足了地基设计承载力要求。碾压区采用冲击碾压技术处理石河子机场跑道地基是可行的,能够实现预期的强度、承载力和差异沉降控制等技术要求。在碾压次数逐渐增加的过程中,地基沉降变形先快后慢,逐渐均匀密实,冲击碾压后,地基反应模量提高幅度较大。
[Abstract]:This paper takes the ground treatment in Shihezi Airport as an example. The technical parameters of dynamic compaction method and roller compaction method in various working conditions of the project are studied and the treatment results are analyzed. Dynamic compaction method is a very economical and simple method for foundation strengthening. The dynamic compaction method is used to reinforce the foundation. The reinforcement effect is obvious, the construction is very simple, and the construction is economical and practical. The ground soil is mainly silty clay in the depth range of dynamic compaction, its geological condition is suitable for ground treatment by dynamic compaction method, and the site is located in the countryside. The site is open and has the external conditions of dynamic compaction construction. The method of dynamic compaction is used to reinforce the foundation. The energy is mainly consumed in the vertical direction, so the reinforcement effect of low liquid limit clay is very obvious. The coefficient of collapsibility (未 s) before consolidation is greater than 0.015, which is collapsible loess. The coefficient of collapsibility (未 s) is less than 0.015 in the range of 0-3m, and the collapsibility is eliminated. The energy level of dynamic compaction is 1000 KN 路m. With the increase of the energy level of dynamic compaction, the reinforcement depth also increases obviously, but when the energy level of dynamic compaction reaches 6 000 KN 路m, the reinforcement depth increases obviously with the increase of energy levels of 2000kN 路m and 3000 KN 路m. The collapsibility of the upper layer of 0-5m can be completely eliminated. For the range below 5m, the collapsibility is partially eliminated, and some of the collapsibility is changed from strong collapsibility to moderate collapsibility. The site compactness, dry density and moisture content of the dynamic compaction level of 6000kN 路m and 4000kN 路m are not obviously increased. The change of compression coefficient and collapsing coefficient is more obvious than that of 16 sites with 3000 KN 路m 2000KN 路m and 1000kN 路m after dynamic compaction. The data obtained from static load test show that the collapsibility of the ground is basically eliminated after the foundation is treated by dynamic compaction method. The change of permeability coefficient in 0-5m is very obvious, and the change of permeability coefficient of 5-6.2m is not obvious, which accords with the judging standard of dynamic compaction effect .6000kN 路m dynamic tamping energy level reinforcement. The permeability coefficient of 4000kN 路m energy level reinforced by dynamic compaction at 0-3m is very obvious, and the permeability coefficient of 3-4.2m is not obvious. This indicates that the influence depth of dynamic compaction energy level of 6000kN 路m is 5 m. The influence depth of 4000kN 路m dynamic compaction energy level is 3m.This also shows that the depth of 6000kN 路m dynamic compaction level for eliminating collapsibility is 5m. The depth of 4000kN 路m dynamic compaction level for eliminating collapsibility is 3m.The permeability coefficient decreases obviously in the treatment depth range, and the reinforcement effect is very remarkable. It meets the requirements of foundation design bearing capacity. It is feasible to use impact rolling technology to treat the foundation of the runway of Shihezi airport in the rolling area, and the expected strength can be achieved. In the process of increasing rolling times, the settlement deformation of the foundation is first fast and then slow, and gradually uniform and compacted, and the response modulus of the foundation increases greatly after impact compaction.
【学位授予单位】：新疆农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU472.31

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