筏板基础大体积混凝土施工裂缝控制研究

发布时间：2018-05-06 02:14

本文选题：筏板基础 + 大体积混凝土　；参考：《大连理工大学》2013年硕士论文

【摘要】：齐齐哈尔市高新园区科技研发中心项目的基础形式为大体积混凝土筏板基础,公司中标该工程后,筏板基础大体积混凝土的施工裂缝控制成为首要任务之一。在查阅了大量国内外相关参考文献后,本文对筏板基础大体积混凝土施工裂缝控制进行了归纳总结,针对该工程筏板混凝土的自身特点,选择经济、合理、实用的措施有针对性的实施于施工过程当中,并在施工过程中通过测温仪器对混凝土中温度进行了监控,针对数据分析制定和调整控温措施,圆满解决了该工大体积混凝土施工裂缝控制问题。近些年在高层建筑中,大体积混凝土筏板基础被广泛应用。由于与普通的混凝土构件相比,大体积混凝土施工时内部水泥水化热相当大并且混凝土的导热性也不佳,对于大体积混凝土施工,稍有控制不慎即有可能因此出现裂缝。这些裂缝可分为表面裂缝和贯穿裂缝,它的引起可能是设计、材料、施工等多方面因素造成的。由于筏板基础多处于地下水位以下或潮湿环境,裂缝一旦产生,水和一些酸碱性物质就会沿裂缝渗透,造成钢筋的锈蚀,引起混凝土产生渗漏,进而引起整个基础的强度降低,影响建筑物的使用功能和耐久性。所以,筏板基础大体积混凝土在施工中必须考虑裂缝控制。本文对筏板大体积混凝土的施工裂缝控制进行的研究,主要包括以下几个方面： (1)在参考文献的基础上,归纳总结了筏板基础大体积混凝土裂缝的分类、产生机理与控制措施,归纳了表面收缩裂缝、温度裂缝控制措施。根据前人经验,拟定了在齐齐哈尔市高新园区科技研发中心项目筏板基础中所采取的裂缝控制措施。 (2)应用有限元软件,筏板混凝土内部温度进行仿真模拟和分析,通过模型中其温度的发展趋势以及温度场的分布情况,制定专门的控温措施。 (3)针对工程特点、参考文献、仿真分析结果,制定了该工程筏板大体积混凝土基础专项施工方案。 (4)施工中对混凝土内部温度发展进行监测,对监测数据进行了对比分析。包括与仿真模型的对比,温度曲线与规范要求限值的对比,以及对引起数值偏差较大的施工措施改进方法。
[Abstract]:The foundation form of science and technology research and development center project of Qiqihar high-tech park is mass concrete raft foundation. After winning the bid for the project, the construction crack control of raft foundation mass concrete becomes the most important Ren Wuzhi. After consulting a large number of references at home and abroad, this paper sums up the crack control of the raft foundation mass concrete construction, according to the characteristics of the raft concrete, the selection of economic, reasonable, The practical measures are carried out in the construction process, and the temperature in the concrete is monitored by the temperature measuring instrument during the construction, and the temperature control measures are formulated and adjusted according to the data analysis. The problem of crack control in large volume concrete construction is solved successfully. In recent years, mass concrete raft foundation has been widely used in high-rise buildings. Compared with ordinary concrete members, the internal hydration heat of cement is quite large and the thermal conductivity of concrete is not good when mass concrete is constructed, so it is possible to cause cracks in mass concrete construction if it is controlled carelessly. These cracks can be divided into surface cracks and penetrating cracks, which may be caused by many factors, such as design, material, construction and so on. As the raft foundation is mostly located below the groundwater level or in a humid environment, once the cracks are formed, water and some acid and alkaline substances will permeate along the cracks, resulting in the corrosion of steel bars, resulting in leakage of concrete, and then causing the strength of the whole foundation to be reduced. Affect the use and durability of buildings. Therefore, crack control must be considered in mass concrete construction of raft foundation. In this paper, the construction crack control of raft slab mass concrete is studied, including the following aspects: 1) on the basis of reference, the classification, mechanism and control measures of mass concrete cracks in raft foundation are summarized, and the control measures of surface shrinkage cracks and temperature cracks are summarized. According to the previous experience, the crack control measures adopted in the raft foundation of the R & D center project of Qiqihar Hi-tech Park are drawn up. 2) the finite element software is used to simulate and analyze the internal temperature of raft concrete. Through the development trend of temperature and the distribution of temperature field in the model, special temperature control measures are worked out. 3) according to the characteristics of the project, the special construction scheme of the raft slab mass concrete foundation is established with reference to the literature and the result of simulation analysis. During construction, the temperature development of concrete is monitored, and the monitoring data are compared and analyzed. It includes the comparison with the simulation model, the comparison between the temperature curve and the limit value required by the code, and the improvement methods for the construction measures which cause the large numerical deviation.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU755.7

【参考文献】