共查询到19条相似文献,搜索用时 281 毫秒
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简要论述了水泥砼路面裂缝的形式,并分析了各种裂缝产生的原因,以求对提高混凝土路面施工质量有所帮助。 相似文献
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根据笔者的多年的工作经验,分析了施工过程中常见的屋面渗漏、混凝土干缩裂缝和抹灰空鼓裂缝等各种常见的质量通病产生的原因,并提出了相应的控制措施,对施工人员有效避免类似施工质量通病有一定借鉴作用。 相似文献
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近年来大量的多层建筑采用砖混结构,由于各种不同的原因,常使砖砌体产生各种形式的裂缝,影响观感和使用,甚至危及房屋的结构安全。因此,正确分析原因、切实加以防治十分必要。 相似文献
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通过观察前嫩公路嫩江公路大桥大体积混凝土裂缝的形式,分析了裂缝产生的原因,同时总结了大体积混凝土在具体施工中阻止或减少裂缝产生的措施。 相似文献
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该文对钢筋混凝土桥梁裂缝产生的原因,裂缝产生的机理进行了分析,并提出裂缝的限值。对林区桥梁的检测和评估有一定的实际意义。 相似文献
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本文对民用建筑物裂缝的产生及其发展进行了科学的分析,讨论了变形变化与荷载变化对建筑裂缝产生的影响,并着重讨论了变形变化对建筑物裂缝产生的影响,指出了各部位裂缝产生的原因及其特征,并从设计、施工及管理维修的不同角度提出了预防和处理裂缝的方法。 相似文献
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混凝土内出现的裂缝按深度的不同,分为贯穿裂缝、深层裂缝及表面裂缝三种。为了保证出现最少的裂缝,就必须在混凝土施工时掌握它的基本性能,并根据实际应用情况采取有效措施,以确保施工质量。 相似文献
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The paper deals with the experimental characterisation of damage evolution within the radial (R)–tangential (T) growth plane of softwood loaded in tension perpendicular to the grain. The reported investigations comprise in-situ monitoring of crack propagation by means of Confocal Laser Scanning Microscopy (CLSM) and evaluations of crack patterns of broken specimens. Three types of notched specimens, representing different crack propagation systems, were tested; for all configurations, both, loading and crack propagation direction were located within the RT plane of wood. The CLSM pictures of broken specimens show distinct differences among the regarded configurations with respect to crack paths. Two different damage mechanisms were identified being rupture of earlywood cell walls in the case of crack propagation in tangential direction and debonding of wood fibers, i.e. rupture of the interface zone between adjacent tracheids, in case of crack progression in radial direction. In the case of an intermediate crack system with an angle of 45° between initial notch direction and radial direction the crack evolution was monitored in-situ during the tension test, whereby the combined action of both basic fracture mechanisms was observed. 相似文献
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谈对混凝土裂缝的处理 总被引:2,自引:0,他引:2
工程结构出现裂缝是比较普遍的现象;而结构裂缝大部分是能够通过设计阶段、施工措施来避免的,本文对构件裂缝的成因、预防及处理进行了详细探讨。 相似文献
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K. Frühmann E. K. Tschegg C. Dai S. E. Stanzl-Tschegg 《Wood Science and Technology》2002,36(4):319-334
Mode I and Mode III loading experiments were performed on side grooved CT specimens of two types of Laminated Veneer Lumber
(LVL). Steady state crack propagation was maintained in order to detect complete load displacement diagrams. Fracture behaviour
and influence of fiber orientation were studied and all important fracture mechanical values (stiffness/compliance, microstructural
damage, crack initiation energy, specific fracture energy etc) were determined. Much higher crack initiation energies and
specific fracture energies resulted in mode III loading than in mode I loading for both material types. Under external mode
III loading, crack initiation occurs in mode III and crack propagation however takes place under mode I owing to crack surface
interference. The influence of fiber orientation on fracture mechanical properties of LVL was discussed.
Received 15 September 1999 相似文献
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本文论述了砌体结构裂缝产生的性质和原因 ,并针对裂缝宽度的标准问题及如何防止墙体开裂构造措施提出几点建议。 相似文献
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杨树的冻裂与预防的初步探讨 总被引:1,自引:0,他引:1
杨树人工林冻裂率为60%以上。冻裂的相关因子为品种、密度、郁闭度、林龄、坡向、植被、抚育一次比抚育三次杨树冻裂少,生长量无大差异。试验证明:对杨树进行涂白、包草和抚育一遍、树干周围留草可以预防杨树冻裂。 相似文献