现浇钢筋混凝土楼板温度收缩裂缝分析及构造措施

现浇钢筋混凝土楼板取代常用的预应力圆孔板已成为必然趋势。但采用现浇钢筋混凝土楼板易产生湿度收缩裂缝。本文对温度收缩裂缝的基本特点及产生原因进行分析，并提出了减少现浇钢筋混凝土楼板温度裂缝的措施。     

混凝土现浇楼板裂缝分析

针对混凝土现浇楼板的裂缝问题，结合工程施工经验，就裂缝产生的原因进行了分析，并提出了避免产生裂缝应采取的防治措施。     

现浇砼楼板施工裂缝的控制及处理

阐述了现浇砼楼板施工裂缝产生的机理、状况及产生的原因，并提出了应抓好砼施工过程中几个重要环节来进行裂缝控制，以及对待施工裂缝的正确态度。     

天面钢筋混凝土楼板裂缝原因及防治措施

分析天面钢筋混凝土楼板裂缝产生的原因，提出了相应的防治措施。     

住宅工程现浇混凝土楼板裂缝的分析与控制

依据民用住宅工程现浇混凝工楼板裂缝的类型及特征,从设计、施工角度探讨了楼板裂缝的性质及产生裂缝的原因,并且针对楼板裂缝的成因,提出了设计、施工方面的裂缝控制措施.     

某综合楼楼板裂缝技术处理方案

以某综合楼楼板为例,分析了楼板裂缝产生的原因,并提出相应的处理方案。     

建筑施工中楼面裂缝的成因及防治

文章针对高层住宅现浇楼板裂缝这一质量通病,结合大量施工实践的经验和教训,阐述了楼板产生裂缝的原因,并探讨了综合防治措施和处理方法,指导实际施工中对楼面裂缝进行有效控制。     

住宅建筑现浇楼板裂缝的成因和防治措施

混凝土现浇楼板是一种量大面广的受力构件，稍有不慎，极易产生裂缝。由于裂缝的产生，对建筑的耐久性，观瞻性及使用功能等均造成影响。导致楼板产生裂缝的因素较多，除了主观意识上的不重视之外，技术上的综合防治措施更是关键。     

住宅楼现浇混凝土楼板裂缝分析和预防措施

住宅楼现浇混凝土楼板工程施工时,经常会出现不同程度的裂缝,这些不同程度的裂缝在施工时应进行有效的防治,避免造成更大的影响。本文就裂缝产生原因和防治措施进行了探讨。     

民用建筑现浇钢筋混凝土楼板裂缝预防与处理

从设计、商品混凝土、现场施工等方面分析了民用建筑钢筋混凝土楼板裂缝的类型和产生原因,并提出预防了建议。     

全现浇钢筋混凝土楼面裂缝的分析及防治措施

在全现浇楼面中，针对容易出现裂缝部位，提出了在设计过程中如何防止现浇楼面裂缝及在施工过程中防止裂缝和现浇楼面出现裂缝后的补救措施。     

大体积混凝土基础裂缝的控制措施

大体积混凝土往往是重要的建、构筑物的基础,它的质量好坏直接决定了上部结构的安全与否。宣钢在大体积混凝土基础施工中通过采用埋设波纹导热管导出混凝土内部热量,优化配合比,降低水化热,严格控制入模温度、分层推进、薄层浇筑,利用应力松驰特性降低内拉应力等一系列措施,使整个养护期间混凝土都处于受控状态,达到了控制降温速率和内外温差的目的,避免了混凝土开裂。     

Field Investigations of Cracking on Concrete Pavements

This paper presents the results of several investigations to identify the underlying causes of longitudinal cracking problems in Portland cement concrete (PCC) pavement. Longitudinal cracking is not intended and detrimental to the long-term performance of PCC pavement. Longitudinal cracking problems in five projects were thoroughly investigated and the findings indicate that longitudinal cracking was caused by: (1) late or shallow saw cutting of longitudinal joints; (2) inadequate base support under the concrete slab; and (3) the use of high coefficient of thermal expansion (CTE) aggregates. When the longitudinal cracks were caused by late or shallow saw cutting of longitudinal joints, cracks developed at a very early stage. However, when there was adequate base support, the longitudinal cracks remained relatively tight even after decades of truck trafficking. Another cause of longitudinal cracking was inadequate base support, and cracking due to this mechanism normally progressed to rather wide cracks. Some cracks were as wide as 57?mm. Evaluations of base support by dynamic cone penetrometer in areas where longitudinal cracks were observed indicate quite weak subbase in both full-depth repaired areas and surrounding areas. This implies that the current requirements for the subbase preparation for the full-depth repair are not adequate. Another cause of longitudinal cracking was due to the use of high CTE aggregate in concrete. Large volume changes in concrete when coarse aggregate with high CTE is used could cause excessive stresses in concrete and result in longitudinal cracking. To prevent longitudinal cracking, attention should be exercised to the selection of concrete materials (concrete with low CTE) and the quality of the construction (timely and sufficient saw cutting and proper selection and compaction of subbase material).     

保证大型水池抗裂防渗的几项措施

对混凝土原材料、膨胀混凝土、后浇带、伸缩缝、施工缝等影响水池结构及裂缝的主要因素进行了深入分析,提出了裂缝控制的措施.     

关于钢筋混凝土施工技术的探讨

现代建筑对钢筋混凝土的施工要求越来越高,钢筋混凝土的灌注是每个工程最重要的环节,要求一次灌注,不间断浇筑。由于混凝土本身的属性,会受温度的影响,一段时间后会出现裂缝等问题,需要施工后精心养护。本文将简单介绍混凝土施工质量的控制,对一些问题提出一些改进的意见。     

浅谈现浇混凝土构件非荷载作用裂缝及其控制

对现浇混凝土构件在温度、收缩变形作用引起裂缝的原因进行了分析，提出了在设计和施工中应采取的控制措施。     

水泥与混凝土裂缝关系的探讨

针对水泥与混凝土裂缝的关系进行了探讨。阐述了产生裂缝的原因并提出了解决的措施。     

地下室防渗控制

地下室工程采用UEA混凝土技术，用膨胀加强带替代后浇缝，通过调整UEA掺量改善混凝土收缩变形，控制裂缝出现，降低混凝土浇筑温度，合理配筋，加强养护，确保地下室无渗漏。     

Melting,Remelting, and Casting for Clean Steel

The control of the metallurgy of steels is now highly developed. This is in contrast to the casting techniques for steels. Although continuous casting is generally conducted well, current ingot casting techniques are poor, unnecessarily introducing masses of oxides. For some steel compositions, double oxide films, bifilms, are entrained. This mechanism, occurring naturally during pouring, but till now generally overlooked, appears to be capable of explaining most of the features of steel defects in all their forms. For most Ni alloys and some steels it appears capable of generating a dense population of cracks, greatly impairing subsequent mechanical working and even final properties. In other steels the effects are much less severe. The techniques to avoid this damage to liquid steels and Ni alloys are described, including contact pouring, and naturally pressurized filling system designs. An ultimate system is counter gravity casting. For remelting processes, the risks of unreliability because of cracks intrinsic to VIM and VAR are discussed for both shop floor production and laboratory research. The potential crack‐free properties of ESR when correctly made are recommended. Even so, remelting processes might constitute an unnecessary luxury if steels and Ni alloys were cast to avoid the entrainment of oxides.