【摘要】：近年來,房地產(chǎn)業(yè)迅猛發(fā)展,土地價格不斷攀升,為了攤薄土地成本,在新建小區(qū)的規(guī)劃中,高層建筑成為重要選擇型式。在高層建筑的基礎設計中,多采用樁基礎、筏板基礎等結(jié)構(gòu)形式,但基礎施工中往往忽視大體積混凝土溫度變形和溫度應力,容易造成溫度裂縫的出現(xiàn)。因此,研究高層建筑基礎大體積混凝土溫度應力控制措施對保證工程施工質(zhì)量有重要的意義。首先,以建筑基礎底板施工中的溫度應力和溫度變形為研究對象,針對溫度應力和溫度變形是混凝土基礎底板裂縫的主要原因這一特點,研究大體積混凝土溫度應力產(chǎn)生和變化的機理,探求防控大體積混凝土底板出現(xiàn)裂縫的施工技術,總結(jié)切實可行的施工經(jīng)驗。其次,通過對大體積混凝土溫度應力變化規(guī)律的研究和溫度應力的計算分析,從理論上闡述控制溫度變形、溫度應力產(chǎn)生原因。通過從設計階段計算、構(gòu)造防止溫度變形的措施,到施工階段改善水泥水化熱、改善混凝土約束條件和構(gòu)造設計措施控制裂縫。另外,通過施工中的溫度監(jiān)測及時掌握混凝土的溫度變化,采取有效控制措施避免溫度裂縫的形成。最后,以具體工程項目的施工實踐,運用大體積混凝土防控溫度裂縫的理論,從施工前的方案制定,到施工過程中采取的控溫措施及施工完成后的養(yǎng)護等方面進行理論驗證,采取措施將混凝土內(nèi)外溫差控制在25℃以內(nèi),降溫速率不大于1.5℃/d,可以保證混凝土的澆筑質(zhì)量。在工程竣工后,工程質(zhì)量良好,未出現(xiàn)有害裂縫。說明本工程在施工中采取的技術措施是得當?shù)摹?br/>[Abstract]:In recent years, with the rapid development of real estate and the rising land price, in order to dilute the cost of land, high-rise buildings have become an important choice in the planning of new residential areas. In the foundation design of high-rise buildings, pile foundation, raft foundation and other structural forms are often adopted, but the temperature deformation and thermal stress of mass concrete are often neglected in the foundation construction, so it is easy to cause the occurrence of temperature cracks. Therefore, it is of great significance to study the temperature stress control measures of mass concrete for high-rise building foundation to ensure the construction quality. First of all, the temperature stress and temperature deformation in the construction of building foundation floor are studied, aiming at the characteristics that temperature stress and temperature deformation are the main causes of cracks in concrete foundation floor. This paper studies the mechanism of the formation and change of temperature stress of mass concrete, explores the construction technology of preventing and controlling cracks in mass concrete floor, and summarizes the practical construction experience. Secondly, through the study of the variation of temperature stress and the calculation and analysis of the temperature stress of mass concrete, the causes of controlling temperature deformation and temperature stress are expounded theoretically. Through the calculation of the design stage, the measures to prevent the temperature deformation are constructed, and the cement hydration heat is improved, the concrete restraint conditions are improved and the cracks are controlled by the structural design measures at the construction stage. In addition, the temperature change of concrete is grasped in time by temperature monitoring in construction, and effective control measures are taken to avoid the formation of temperature crack. Finally, according to the construction practice of the concrete project, using the theory of mass concrete to prevent and control the temperature crack, from the formulation of the plan before the construction, to the temperature control measures adopted in the construction process and the maintenance after the completion of the construction, the theoretical verification is carried out. If the temperature difference between inside and outside of concrete is controlled within 25 鈩，

本文編號：2443514