以切线模量法确定地基承载力的研究
发布时间：2018-07-24 13:34
【摘要】：本文对使用切线模量法合理确定地基承载力进行了研究。通过使用太沙基公式计算极限承载力，并使用切线模量法计算实际基础的p-s曲线，通过基础沉降和安全系数两个方面进行控制，以确定合理的地基承载力。具体工作为： 1、通过设定的4种土体，利用FLAC数值方法，设定不同宽度的基础，对太沙基极限承载力公式的宽度效应进行了验证，说明太沙基公式中宽度对承载能力的贡献是基本正确的。但对于软土，太沙基公式中宽度取值应采用实际基础宽度的一半。 2、对于规范采用限定基础宽度大于6m时按6m计算来确定地基承载力特征值的情况进行了研究。通过计算不同尺寸时4种软硬不同的地基的极限承载力，其中采用FLAC数值方法和太沙基极限承载力公式进行计算；对于沉降使用以Mohr-Coulomb为本构模型的数值方法和切线模量法计算，按强度安全系数和沉降双控原则确定承载力，，与规范方法确定的承载力进行了比较。结果表明规范方法确定承载力时，在硬土地基上沉降较小偏保守，在软土地基上会出现沉降过大而偏不安全。因此，合理确定承载力的方法应是按强度安全系数和沉降双控原则。 3、利用几个原位压板试验和实际工程案例，对以切线模量法确定承载力进行了验证，证明采用太沙基公式计算极限承载力，使用切线模量法计算沉降，通过双控原则确定承载力更符合工程实际。
[Abstract]:In this paper, the method of tangent modulus is used to determine the bearing capacity of foundation. The ultimate bearing capacity is calculated by using the Taishaki formula and the p-s curve of the actual foundation is calculated by using the tangent modulus method. The foundation settlement and safety factor are controlled to determine the reasonable bearing capacity of the foundation. The specific work is as follows: 1. The width effect of the ultimate bearing capacity formula of Terzaghi is verified by the FLAC numerical method and the foundation of different widths. It shows that the contribution of width to bearing capacity is basically correct. However, for soft soil, the width should be taken as half of the actual foundation width in the formula of Taishaji, and the characteristic value of foundation bearing capacity should be calculated according to 6m when the limited width of foundation is greater than 6m in the code. The ultimate bearing capacity of four different soft and hard foundations with different sizes is calculated, in which FLAC numerical method and Terzaghi ultimate bearing capacity formula are used to calculate the settlement, and the Mohr-Coulomb constitutive model and tangent modulus method are used to calculate the settlement. The bearing capacity is determined according to the principle of strength safety factor and double control of settlement, and compared with the bearing capacity determined by the standard method. The results show that when the bearing capacity is determined by the code method, the settlement on the hard soil foundation is less conservative, and the settlement on the soft soil foundation is too large and unsafe. Therefore, the reasonable method of determining bearing capacity should be based on the principle of strength safety factor and double control of settlement. 3. Several in-situ compression plate tests and practical engineering cases are used to verify the determination of bearing capacity by means of tangent modulus method. It is proved that the ultimate bearing capacity is calculated by using the Taizhaji formula and the settlement is calculated by the tangent modulus method. The calculation of the bearing capacity by double control principle is more in line with the engineering practice.
【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU470
本文编号：2141543
[Abstract]:In this paper, the method of tangent modulus is used to determine the bearing capacity of foundation. The ultimate bearing capacity is calculated by using the Taishaki formula and the p-s curve of the actual foundation is calculated by using the tangent modulus method. The foundation settlement and safety factor are controlled to determine the reasonable bearing capacity of the foundation. The specific work is as follows: 1. The width effect of the ultimate bearing capacity formula of Terzaghi is verified by the FLAC numerical method and the foundation of different widths. It shows that the contribution of width to bearing capacity is basically correct. However, for soft soil, the width should be taken as half of the actual foundation width in the formula of Taishaji, and the characteristic value of foundation bearing capacity should be calculated according to 6m when the limited width of foundation is greater than 6m in the code. The ultimate bearing capacity of four different soft and hard foundations with different sizes is calculated, in which FLAC numerical method and Terzaghi ultimate bearing capacity formula are used to calculate the settlement, and the Mohr-Coulomb constitutive model and tangent modulus method are used to calculate the settlement. The bearing capacity is determined according to the principle of strength safety factor and double control of settlement, and compared with the bearing capacity determined by the standard method. The results show that when the bearing capacity is determined by the code method, the settlement on the hard soil foundation is less conservative, and the settlement on the soft soil foundation is too large and unsafe. Therefore, the reasonable method of determining bearing capacity should be based on the principle of strength safety factor and double control of settlement. 3. Several in-situ compression plate tests and practical engineering cases are used to verify the determination of bearing capacity by means of tangent modulus method. It is proved that the ultimate bearing capacity is calculated by using the Taizhaji formula and the settlement is calculated by the tangent modulus method. The calculation of the bearing capacity by double control principle is more in line with the engineering practice.
【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU470
【参考文献】
相关期刊论文 前10条
1 刘庆潭,刘启凤,华祖q ,魏丽敏;用极限平衡方法确定加筋土地基的极限承载力[J];长沙铁道学院学报;1997年04期
2 滕延京;;《建筑地基基础设计规范》地基承载力概念的理解与应用[J];工程勘察;2004年03期
3 顾宝和;;地基承载力的来龙去脉[J];工程勘察;2004年03期
4 杨光华;关于岩土力学与工程的发展问题[J];广东水利水电;2000年06期
5 杨光华;根据经验地基承载力反算土的强度和变形参数[J];广东水利水电;2002年01期
6 张卢明;郑明新;何敏;郑玉之;;深基坑开挖与锚杆支护FLAC~(3D)数值模拟分析[J];华东交通大学学报;2007年05期
7 张展君;朱小林;;基础埋深对地基承载力的影响[J];结构工程师;1990年03期
8 翟洪飞;宰金珉;;地基承载力确定标准的研究[J];江苏建筑;2007年02期
9 蒋洪胜;浅基础地基承载力的若干问题[J];建筑技术;2000年03期
10 滕延京;地基基础设计规范与国外规范分项安全系数取值对比分析[J];建筑科学;1999年05期
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