The Analysis Of Crack For Continuously Reinforcement Concrete Pavement In Cold Area

CRCP(continuously reinforced concrete pavement) has already beenapplied widely in many countries due to its multitudinous fineperformance. Systematic research has also been carried out in this field inour country. This paper makes an in-depth analysis of the crack situationof CRCP based on the It mainly studies the crack formation mechanism,reinforced concrete bonding properties and the temperature's stress on thecrack index, According to theoretical analysis and test results, this papersuggests the application of partition linear caking relations in the CRCPtheoretical analysis, and the reasonable ratio of reinforcement and steelbar diameter considering temperature stress.For the superiority with which plain concrete road surface is unableto compare, CRCP has already been studied extensively and appliedwidely in foreign countries. In China, when the country is taking greateffort to construct the super highway, it is of great significance to studythe CPCP in deep level based on the northern climate which ischaracterized by chilliness. Although initial investment of CRCP is high,yet its inherent superiority enhances the performance and durability of theroad, and it is also suitable for weak soil conditions and the areas with bigtemperature disparity. In the long run, CRCP is economic and reasonable,and enjoys a broad prospect for application.The thesis introduces the mechanism of CRCP crack formation,analyzes the reasons for CRCP early crack formation and the factorsinfluencing the pavement performance, and points out some questionswhich should be paid attention to in construction.As a concrete roadsurface structure with good performance, CRCP makes full use of thebonding properties between steel bar and concrete. Without transversejoint on the road surface, very big internal stress will be inevitablygenerated within the concrete due to the great temperature disparity in thenorth and big difference in temperature between the day and the night. Bydisposing steel bar in the concrete slab, the concrete internal stress wouldbe restrained, and the tiny and even crack which is in accordance with thedesign request would be generated. The paper first gives a theoreticalaccount of the bonding test sample, promotes the dynamic relationsbetween the bonding stress and relative slip along steel bar length, then itmeasures the result of gauge on steel bar by pasting strain and concrete.The analysis of the data and a comparison of the results show a gooduniformity of .the theoretical analysis and the experimental value.哈Meanwhile, considering the fact that the temperature difference in thenorth is within the reinforcement stress linear scope, this paper adoptsspring unit to carry out finite element numerical analysis of the bondingtest sample, and finds that the result is similar to the tested data. Bycomparing three results, the paper draws the conclusion that bondingstress and relative slip between thread steel bar in CRCP and concreteappear partition linearity relations. So the paper suggests partitionlinearity bonding relations should be used to analyze reinforced concreteon temperature stress. And it illuminates the condition of assumingboundary ddys y=0 =0 is reasonable in the analysis of bonding theories.The article Introduces the influence factors of crack width and crackspace, and domestic computational method nowadays. Considering CRCPthese two important indexes, the paper uses bonding relations whichchapter three has promoted to carry on temperature stress analysis, anddraws crack indexes corresponding conclusions under the condition oftemperature stress function by procedure established(a)When the ratio ofreinforcement increases, crack width and crack space will reduce.(b)When the diameter of steel bar increases, crack width and crack spacewill increase.(c) When crack space increases, crack width will increase.(d) When concrete linear expansion coefficient increases, crack spacewill reduce and crack width will increase slightly.(e) When bondingstress increases, crack width and crack space will reduce.If CRCP would be constructed in north cold area, this paper suggests0.0070-0.008 as the ratio of reinforcement in engineering design, and0.012-0.016 meter as the steel bar diameter. CRCP will inevitablygenerate crack under the function of various conditions, so this paperanalyzes the sensitive index of crack forming to control crack to the best.Moreover, it proposes some questions which should be paid attention to inconstruction to reduce crack based on the characteristic of the northernclimate with great temperature disparity.and the paper summarizes all thework done in the process of writing this paper, and proposes the contentsand directions for the future research.