吹填土路基处理技术及加固效果评价

发布时间：2018-07-17 00:09

【摘要】：吹填造陆已经成为解决沿海城市土地资源短缺的重要途径,而由于吹填土承载性能一般很差,因此,吹填土地基处理是岩土工程领域的重要问题之一。由于处置效果较好,费用较低,施工工艺成熟,采用真空预压法进行吹填土地基的处理,已经成为一种重要选择。吹填土地基处理后一般用作建筑物基础,当其用作公路路基时,由于对沉降和不均匀沉降更为严格,采用真空预压法进行吹填土地基处理是否可满足工程要求,尚需要结合工程实际,进行施工技术和处理效果的进一步检验。为了验证吹填土路基处理技术的可行性,并检验其处置效果,本文以天津临港产业区纬六路的地基处理为工程依托,对真空预压法处理吹填土路基的施工技术、施工要求进行了较为详细的研究,并对其处置效果进行了检验和评价,结合工程实际,对路基结构设计进行了简要评述,主要结论如下:(1)真空预压法处理公路地基的施工技术研究。根据工程基本设计资料,对真空预压法的关键参数和施工工艺进行了设计和实施。对于真空预压的关键参数,要求膜下真空度稳定保持且不小于85kPa,有效真空天数不少于90天。(2)真空预压法处理公路地基的工程质量检验。对真空预压法的处置效果,从处置后土体性质、孔隙水压力、沉降等方面进行了长期监测,并根据监测数据对处置效果进行了评价。监测结果表明,真空预压区在预压期间沉降量,满足设计卸载要求。处置前后的十字板剪切结果和土体的物理力学指标检测表明,加固后土层物理力学性质明显改善,土壤抗剪强度指标增长显著,达到了地基处理的目的。(3)吹填土路基结构设计。由于工期可能很紧,吹填预压完成时间很短就需进行道路施工,吹填部分仍处于密实度差、含水量大的状态,根据真空预压处理后地表距设计路面标高距离路基进行了结构设计。总体来看,吹填土路基在真空预压地基之后,只要结合工程实际进行严密的路基设计与施工,可满足公路工程的质量控制要求。
[Abstract]:Reclamation land has become an important way to solve the shortage of land resources in coastal cities. However, because of the poor bearing capacity of filling soil, the treatment of soil foundation is one of the most important problems in geotechnical engineering. Because the disposal effect is better, the cost is lower, and the construction technology is mature, it has become an important choice to use the vacuum preloading method to treat the filling foundation. When used as roadbed of highway, it is more strict to settlement and uneven settlement, so whether it can meet the engineering requirements by using vacuum preloading method to treat the foundation is generally used as building foundation. It is necessary to further test the construction technology and treatment effect combined with the engineering practice. In order to verify the feasibility of filling subgrade treatment technology and test its disposal effect, this paper bases on the foundation treatment of Wailiu Road in Tianjin Lingang Industrial District, and makes use of the construction technology of vacuum preloading method to treat the filling subgrade. The construction requirements are studied in detail, the disposal effect is tested and evaluated, and the design of the subgrade structure is briefly reviewed in combination with the engineering practice. The main conclusions are as follows: (1) study on construction technology of highway foundation treatment by vacuum preloading method. According to the basic design data, the key parameters and construction technology of vacuum preloading method are designed and implemented. For the key parameters of vacuum preloading, the vacuum degree under film should be kept stable and not less than 85 KPA, and the effective vacuum days should not be less than 90 days. (2) the quality inspection of highway foundation treatment by vacuum preloading method. The treatment effect of vacuum preloading method is monitored in terms of soil properties, pore water pressure, settlement and so on, and the effect of disposal is evaluated according to the monitoring data. The monitoring results show that the settlement of vacuum preloading zone during preloading can meet the requirements of design and unloading. The shear results of cross plate and physical and mechanical indexes of soil before and after disposal show that the physical and mechanical properties of soil layer are obviously improved, and the shear strength index of soil increases significantly after reinforcement, which achieves the purpose of foundation treatment. (3) structural design of roadbed with blowing fill. Because the construction period may be very tight and the completion time of preloading is very short, road construction is required. The filling part is still in a state of poor compactness and high water content. Based on the surface distance design after vacuum preloading, the structure of pavement elevation roadbed is designed. As a whole, after vacuum preloading, the design and construction of roadbed can meet the requirements of highway engineering quality control.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U416.1

【相似文献】