浅谈混凝土的施工温度与裂缝

通过多年的现场观察和查阅有关混凝土内部应力方面的专著,对混凝土温度裂缝产生的原因、混凝土温度的控制和预防裂缝的措施等进行阐述。     

浅谈温度对混凝土裂缝的影响及预防措施

通过多年的现场观察并查阅有关混凝土内部应力方面的专著,对混凝土温度裂缝产生的原因、现场混凝土温度的控制和预防裂缝的措施等进行阐述。     

谈谈钢铁厂大型设备基础-混凝土的施工温度与裂缝

通过多年的现场观察，结合查阅有关混凝土内部应力方面的专著，对混凝土温度裂缝产生的原因、现场混凝土温度的控制和预防裂缝的措施等进行深入的阐述。指出引起裂缝的原因主要是温度和湿度变化等。并提出采取防止裂缝的相应措施。主要改善内部和外部约束条件。     

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。     

浅谈混凝土的温度裂缝

经多年的施工监理实践,在查阅有关混凝土内部应力方面的专著后,对混凝土温度裂缝产生的原因、现场混凝土温度的控制和预防混凝土温度裂缝的措施进行阐述。     

浅谈混凝土的施工温度与裂缝控制

水泥混凝土工程施工过程中,经常发生一些裂缝,影响结构的安全,如何最大限度的避免裂缝产生,保证工程结构安全,是工程管理人员急需掌握的,本文就结合工作实际,对混凝土工程的裂缝的产生和防治进行探讨.     

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。     

某工程地下室纵墙裂缝的分析与处理

本文对某工程地下室纵墙裂缝发生的成因，机理过程进行分析，表述了对带有地下室框架结构温度变开缝的认识，提出地下室纵墙裂缝的防治措施。     

浅谈水泥混凝土路面早期裂缝的成因与防治

以温差大、地材质量较差的施工条件下新建的水泥混凝土路面为例,对其出现早期裂缝的原因进行分析,并提出裂缝的预防和处理措施。     

混凝土浓缩池质量事故分析与处理

对Φ８０ｍ混凝土浓缩池施工中出现的贯穿裂缝，具体从地基土质、温差应力及混凝土本身缺陷几个方面进行了分析，得出裂缝处理措施，并应用于Φ１４０ｍ混凝土浓缩池的施工中，取得良好的效果。     

混凝土裂缝成因与控制

混凝土裂缝的成因很多。对其正确的判断和有效的分析,根据情况对设计、材料选择、现场操作等环节进行控制,将会大大减少混凝土裂缝,保证建筑质量。     

冬季混凝土的裂缝控制

分析了混凝土强度和受冻的关系及混凝土早期冻害的原因。找出预防混凝土早期冻害的技术措施和解决混凝土冬期施工的方法，保证裂缝在允许范围内行之有效的方法。     

混凝土裂缝原因分析及预防措施

本文从混凝土内外应力的角度深刻分析了混凝土裂缝产生的原因,提出了预防措施,供与结构设计、工程管理同行交流。     

Crack Propagation in Flexural Fatigue of Concrete

In this paper the behavior of concrete subjected to flexural fatigue loading is studied. Notched concrete beams were tested in a three-point bending configuration. Specimens were subjected to quasi-static cyclic and constant amplitude fatigue loading. The cyclic tests were performed by unloading the specimen at different points in the postpeak part of the quasi-static loading response. Low cycle, high amplitude fatigue tests were performed to failure using four different load ranges. The crack mouth opening displacement was continuously monitored throughout the loading process. Crack propagation caused by quasi-static and fatigue loads is described in terms of fracture mechanics. It is shown that the crack propagation in the postpeak part of the quasi-static load response is predicted using the critical value of the mode I stress intensity factor (KIC). The ultimate deformation of the specimen during the fatigue test is compared with that from the quasi-static test; it is demonstrated that the quasi-static deformation is insufficient as a fatigue failure criterion. It is observed that crack growth owing to constant-amplitude fatigue loading comprises two phases: a deceleration stage when there is a decrease in crack growth rate with increasing crack length, followed by an acceleration stage where the rate of crack growth increases at a steady rate. The crack length where the rate of crack growth changes from deceleration to acceleration is shown to be equal to the crack length at the peak load of the quasi-static response. Analytical expressions for crack growth in the deceleration and acceleration stages are developed, wherein the expressions for crack growth rate in the deceleration stage are developed using the R-curve concept, and the acceleration stage is shown to follow the Paris law. It is observed that the crack length at failure for constant amplitude fatigue loading is comparable to that of the corresponding load in the postpeak part of the quasi-static response. Finally, a fracture-based fatigue failure criterion is proposed.     

混凝土裂缝成因与控制

判断和分析混凝土裂缝的成因是有效地控制和减少混凝土裂缝产生的最有效的途径。混凝土的裂缝是一个综合性的问题，主要是由结构构件的设计、材料的选用、混凝土的配合比、施工环境以及外界因素等多方面原因造成的。混凝土裂缝的控制应从这几个方面进行综合考虑。     

Fictitious Crack Propagation in Fiber-Reinforced Concrete Beams

A nonlinear cracked hinge model is developed, aimed at the analysis of the bending fracture of fiber-reinforced concrete beams. The model is based on the fracture mechanics concepts of the fictitious crack model with a bilinear stress-crack opening relationship. Closed-form solutions are presented for the moment-rotation relationship of the hinge as a crack propagates, and the case of a nonzero normal force is covered. Special shapes of the stress-crack opening relationship are treated separately. These shapes are the so-called drop-linear and the drop-horizontal for which simplified expressions are obtained. The applicability of the hinge model is demonstrated through analysis of the bending fracture process in the case of a three-point bending beam and an infinitely long beam on a Winkler foundation, the latter analysis comprising the effect of a constant tensile normal force.     

浅谈如何控制超长混凝土水池裂缝

本文介绍了超长水池产生裂缝的主要原因有温差引起的裂缝、混凝土的收缩、水化热、施工质量差、混凝土的保养;针对这些原因而采取的一些防止裂缝产生的措施,如设温度缝、设置后浇带、使用预应力混凝土、减小地基对水池的约束作用。     

Simulation of Crack Growth in FRP Reinforced Concrete

Experimental results show that the crack growth of fiber-reinforced polymer (FRP) reinforced concrete flexural elements experience a crack development stage followed by crack stabilization. The crack length and elastic crack mouth opening displacement (CMOD) increase during the crack development stage until reaching the crack stabilization stage. A finite-element representation was proposed to predict the initial CMOD. A debonded length was specified to account for the bond-slip between FRP bar and concrete. It was assumed that there was no tangential displacement between the reinforcement and concrete outside of the debonded length. A fatigue model was created using the Paris equation to simulate the growth of elastic CMOD. The model displayed good agreement with the test results. A size effect was also observed for the exponential parameter in the Paris equation.     

浅谈钢筋砼现浇板裂缝的预防

分析钢筋混凝土现浇板产生裂缝的原因,主要论述温度-收缩应力对钢筋混凝土现浇板产生裂缝的影响。对温度-收缩应力作用产生裂缝提出预防措施。