水泥混凝土路面裂缝的成因及其防治

文章通过对水泥砼路面产生裂缝内外因素进行分析，结合公司近几年来住宅小区和厂矿道路已建成通车的水泥混凝土路面的使用情况，从设计、施工、养护三方面分析了水泥混凝土路面破坏的原因及其预防和处治措施，对水泥混凝土路面裂缝的产生及避免进行了一些探讨。     

橡胶沥青应力吸收层在旧路面改造中的应用

分析了水泥混凝土路面沥青加铺层反射裂缝的产生机理,介绍橡胶沥青应力吸收层良好的抗反射裂缝效果及其路用性能.结合金溪县秀谷中大道改造工程的设计、施工情况,阐述了橡胶沥青应力吸收层在旧路面改造中的应用.     

如何预防水泥混凝土路面的裂缝和断板

介绍了水泥混凝土路面几种常见裂缝类型,并进行了简要的原因分析,提出了预防水泥混凝土路面裂缝(或断板)的措施。     

钢铁厂水泥混凝土路面裂缝原因分析与防治措施

阐述了河北钢铁集团唐钢公司南区内水泥混凝土路面常见裂缝的原因与防治措施。     

混凝土路面裂缝原因分析及防控措施

本文对贵溪冶炼厂混凝土路面破坏现象进行深入研究 ,分析了混凝土路面裂缝的原因 ,提出了防控混凝土路面裂缝的措施     

基于有限元的水泥混凝土路面裂缝加装传力杆维修分析

使用三维有限元软件对传力杆在水泥混凝土路面裂缝维修中的应用进行了分析.主要内容包括:1)加装传力杆作用分析;2)不同位置横向裂缝加装传力杆的效果分析.通过加装传力杆对裂缝传荷能力及板内应力的影响分析,得出水泥混凝土路面裂缝加装传力杆是可行的.     

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。     

水泥混凝土路面厚度计算的思考

根据某条道路的设计实例，在计算水泥混凝土路面厚度时分别采用了《城市道路设计规范》和《公路水泥混凝土路面设计规范》中所规定的设计方法，对得出的两种结果进行了对比，并分析了两种设计方法的相同和不同之处。     

水泥粉煤灰碎石基层沥青面层反射裂缝机理与措施

对水泥粉煤灰稳定碎石基层收缩开裂及反射裂缝的产生与扩展机理进行了分析,提出了抑制和延缓水泥粉煤灰稳定碎石基层开裂及沥青面层反射裂缝产生与扩展的措施。     

寒冷地区混凝土路面工程伸缩缝早期振缝法施工

在东北寒冷地区混凝土灰白色路面较为普通。由于温度变化大、混凝土伸缩缝的施工质量达不到规范要求等因素，混凝土面层易产生不规则裂缝，严重者只得第二年返工。     

粉煤灰混凝土的试验研究

文章对掺粉煤灰混凝土的系列配合比进行设计,经对粉煤灰掺量分别为20%、25%、30%的系列粉煤灰混凝土配合比进行试验,其中掺量为25%的粉煤灰混凝土其工作性能效果最佳。粉煤灰混凝土的优点是混凝土的工作性能好,混凝土坍落度损失小,适用于商品混凝土及远距离运输,提高工程质量,节约水泥,降低混凝土成本,节约资源等。     

掺入矿渣粉的混凝土抗硫酸盐侵蚀的研究

通过包钢厂区蓄水池的掺入矿渣粉的混凝土的研究,来表述混凝土中掺入矿渣粉效应。通过矿渣粉在砼中替代水泥质量的不百分比,砼在不同的矿渣粉掺量下的流动度、强度和抵抗硫酸盐侵蚀的能力,来评价矿渣粉在混凝土中的作用：掺入一定量的矿渣粉的混凝土,其工作性能和力学性能远远高于未掺矿渣粉的混凝土,并且在试验中找到了蓄水池混凝土中矿渣粉的最佳掺量,不仅降低了成本,而且还保证了混凝土的实用性。     

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。     

Construction Quality Control for Asphalt Concrete Hydraulic Barriers

Asphalt concrete has been used for low permeability barriers in numerous applications over many centuries. In recent times, asphalt concrete barriers have been used for waste containment applications. The hydraulic conductivity of asphalt concrete specimens can be measured in the laboratory; however, there is no expedient, efficient way of accurately measuring the in situ hydraulic conductivity of low permeability asphalt concrete shortly after its placement and compaction in the field. A method has been developed to efficiently check the in situ hydraulic conductivity of asphalt concrete in the field. Asphalt concrete specimens with varying asphalt cement contents and unit weights were prepared in the laboratory and their hydraulic conductivity measured. The measured hydraulic conductivity data were grouped into different ranges and plotted as a function of unit weight and asphalt cement content. An acceptable zone was specified for a combination of asphalt cement content and unit weight that resulted in a specified hydraulic conductivity. In the field, a quality control inspector can check the unit weight and asphalt cement content of the in-place barrier to make sure it lies within the acceptable zone. The asphalt cement content and unit weight can be readily measured, thereby allowing rapid acceptance or rejection of the asphalt concrete barrier shortly after compaction.     

粒化高炉渣在混凝土中的应用

研究了粒化高炉渣在混凝土中的应用。通过大量的实验证明，在中低强度混凝土中，粒化高炉渣可大量地等量替代水泥(最佳掺量为40％～50％)，从而降低混凝土生产成本，同时可有效改善混凝土的和易性。在高强度混凝土中又是必不可少的良性矿物外加剂，不仅能提高强度，而且可提高和易性和耐久性等各项性能指标，可生产出C80以上的混凝土。     

加气混凝土砌块墙体裂缝产生的机理及防治

加气混凝土砌块在应用中,由于本身的干缩变形等特点会导致墙体裂缝现象。本文从分析加气混凝土砌块的主要特点入手,探讨了加气混凝土砌块墙体裂缝形成的机理及产生的原因,并提出了相应的防治措施。     

高炉基础掺外加剂耐热混凝土的应用

介绍了掺外加剂耐热混凝土在高炉基础上的应用。通过试验 ,得出了掺外加剂耐热混凝土在泵送条件下的配合比为 (kg/m3) :水 2 80 ;水泥 3 5 0 ;耐火砖块 80 0 ;粘土砂 63 0 ;掺合料 180 ;FDⅡ型高效减水剂 3 .5。     

Effects of Temperature Variations on Precast, Prestressed Concrete Bridge Girders

The monitoring of a precast, prestressed girder bridge during fabrication and service provided the opportunity to observe temperature variations and to evaluate the accuracy of calculated strains and cambers. The use of high curing temperatures during fabrication affects the level of prestress because the strand length is fixed during the heating, the coefficients of thermal expansion of steel and concrete differ, and the concrete temperature distribution may not be uniform. For the girders discussed here, these effects combined to reduce the calculated prestressing stress from the original design values at release by 3 to 7%, to reduce the initial camber by 26 to 40%, and to increase the bottom tension stress in service by 12 to 27%. The main effect of applying the standard service temperature profiles to the bridge was to increase the bottom stress by 60% of the allowable tension stress. These effects can be compensated for by increasing the amount of prestressing steel, but in highly stressed girders, such an increase leads to increased prestress losses (requiring yet more strands) and higher concrete strength requirements at release.     

Finite Element Analysis of Concrete Pavements Over Culverts

Accelerated distress of Portland cement concrete pavements (PCCP) over structures such as culverts, pipes, and tunnels beneath roadways is a common occurrence. In this article, finite element analysis is employed to analyze the response of concrete pavements over such structures. The factors that influence the overlying pavement slabs include: (1) cover depth, (2) pavement slab thickness and length, (3) cement concrete elastic modulus, (4) foundation modulus, and (5) backfill soil modulus. The tensile stresses at the bottom and top of the slab induced by wheel loads are predicted. In the traditional pavement design only the tensile stress at the bottom of the slab is considered to be significant. However, this study shows that the tensile stress at the top surface of pavement slabs over culverts may also cause the concrete pavements to fail. A laboratory model was employed to study the mechanical characteristics of Portland cement concrete pavement slabs over culverts and to verify the theoretical analysis.