Time-varying Reliability Analysis of Long-span Continuous Rigid Frame bridge under Cantilever Construction Stage based on the Monitored Strain Data

In general,the material properties,loads,resistance of the prestressed concrete continuous rigid frame bridge in different construction stages are time-varying.So,it is essential to monitor the internal force state when the bridge is in construction.Among them,how to assess the safety is one of the challenges.As the continuous monitoring over a long-term period can increase the reliability of the assessment,so,based on a large number of monitored strain data collected from the structural health monitoring system(SHMS)during construction,a calculation method of the punctiform time-varying reliability is proposed in this paper to evaluate the stress state of this type bridge in cantilever construction stage by using the basic reliability theory.At the same time,the optimal stress distribution function in the bridge mid-span base plate is determined when the bridge is closed.This method can provide basis and direction for the internal force control of this type bridge in construction process.So,it can reduce the bridge safety and quality accidents in construction stages.

Construction Technology and Quality Control of Double Layer Continuous Paving of Cement Stabilized Macadam Base

The construction method of continuous paving of the upper and lower base of the water stable macadam base can improve the construction efficiency,overcome the quality problems of the traditional layered paving of the upper and lower base,such as untimely curing,slow construction,poor interlayer bonding,contraction joint and interlayer,so as to ensure the construction quality of the water stable macadam.It is also the promotion and application of new technology.

Key Technology and Complete-set Equipment for Intelligent Construction of HSR Simply-supported Girder Reinforcement Framework

In view of the problems such as backward production mode,poor quality stability,high safety risk and incomplete control system during erection of the reinforcement framework of simply-supported box girders for high-speed railway(HSR),and in combination with the key points and main challenges in the reinforcement framework construction of Guangzhou-Zhanjiang HSR,the overall technical route for the intelligent manufacturing of reinforcement framework of simply-supported box girders is put forward.The component design of reinforcement framework of simply supported box girder is carried out based on BIM,and the feasibility of the scheme is verified through segment assembly test.The assembly techniques are studied in combination with the mesh design scheme to achieve rapid forming of the reinforcement framework.R&D of automatic processing equipment for components,material transshipment equipment,automatic hoisting equipment and technological equipment for assembly clamping fixture are carried out to realize the overall design of equipment production line.An intelligent control system is developed for the whole-process intelligent construction of reinforcement framework to realize the full life-cycle applications for the workshop production and visual management including intelligent layout and quality traceability.The research results systematically optimize and innovate the assembly and forming technologies of reinforcement framework in the prefabrication beam yard of high-speed railway,realize the component processing,automatic assembly and information technology management,improve the construction quality,efficiency and information technology level of intelligent manufacturing of reinforcement framework of railway prefabricated beam as a whole,and reduce the construction cost of the project.The research has realized a major breakthrough in the construction technology of railway prefabricated box girders,which has the extensive technical and market promotion values.

Design and Construction Strategy of Arched Continuous Rigid-frame Bridge

With the current rapid development of urbanization in China,people's living standards have been greatly improved.In the context of such a development background,the requirements for road traffic are getting more stringent,especially for bridge projects.The arched continuous rigid-frame bridge was developed under this social background.The advantage of the bridge lies in the design of a bridge model that integrates various functions such as transportation,landscape,and sightseeing.Based on the above,this paper first refers to the case to analyze the design and construction strategy of the arched continuous rigid-frame bridge,in hope of providing a valuable reference for relevant personnel.

Application of Long-Span Continuous Bridge Technology in Bridge Construction

In order to promote the rapid development of urbanization in our country,it is necessary to improve the construction level and technology of bridge engineering.For long-span continuous bridge technology,it has the characteristics of wide application range,various applicable conditions,and short construction period.Therefore,it is necessary to pay attention to the application of long-span continuous bridge technology.This article mainly analyzes its application in bridge construction,hoping to provide some reference for future use.

On Chinese Civilization Being the Only Continued Civilization in the Viewpoint of the Modern National History Construction

Chinese civilization is the only ancient civilization thriving to this day seems to be a common view in the historical academia and Chinese society as well. Culture is a way that human beings actively adapt to the surroundings and keep consistence with environmental change. All cultures created by human beings are changing, so is the Chinese culture. The physical and cultural evolution presented by the archaeological discoveries and related historical researches show that Chinese culture is multi-sourced and multicultural. This is the secret for the Chinese culture to retain its vitality. The reasons that Chinese civilization is the only civilization thriving to this day among all of ancient civilizations in the world include the ancestral worship, the identity to common ancestors, traditions of writing pedigrees and history books, the longhistory Chinese character system and the creative thinking and cultural methods of interpreting new thoughts by using traditional Chinese thinking and cultural structures. Especially in modern times, impacted by the nationalism trend, the national state narration built for meeting the requirement of the national state"historical memory"left us the strong impression of Chinese civilization being the only continued civilization and fostered the affective identification with the common history.

Longitudinal forces of continuously welded track on high-speed railway cable-stayed bridge considering impact of adjacent bridges

A proven beam-track contact model was used to analyze the track-structure interaction of CWR (continuously welded track) on bridge. Considering the impact of adjacent bridges, the tower-cable-track-beam-pier-pile finite element model of the cable-stayed bridge was established. Taking a bridge group including 40-32m simply-supported beam and (32+80+112)m single-tower cable-stayed bridge and 17-32m simply-supported beam on the Kunming-Shanghai high-speed railway as an example, the characteristics of CWR longitudinal force on the cable-stayed bridge were studied. It is shown that adjacent bridges must be considered in the calculation of the track expansion force and bending force on cable-stayed bridge. When the span amount of adjacent bridges is too numerous, it can be simplified as six spans; the fixed bearing of adjacent simply-supported beams should be placed on the side near the cable-stayed bridge; the track expansion device should be set at the bridge tower to reduce the track force near the bridge abutment.

The Construct of the Story Continuation Writing Task: Insights From the China’s Standards of English Language Ability

Although the story continuation writing task(SCWT) has attracted much research attention, few studies have investigated the construct of the task, particularly with respect to which language competence it focuses on. In addition, although some studies have demonstrated that China’s Standards of English Language Ability(CSE) provides comprehensive insights into the development of Chinese learners’ English language proficiency, little research has investigated the relationship between CSE and SCWT. This study drew upon the CSE to develop an SCWT language use inventory to address the above research gaps. A total of 358 high school students were asked to complete the questionnaire, of which 277 valid responses were analyzed. Exploratory factor analysis(EFA) on the CSE-based questionnaire revealed the presence of six factors, namely language correctness, language variety, task planning, connecting-and-generating, selecting-andmining, and organizing. The strategy of connecting-and-generating was the only significant predictor of the learners’ SCWT scores. The paper also discusses the findings relating to the SCWT rating and other integrated writing tasks.

Bridge Falsework in Staged Construction of a Prestressed Concrete Beam Bridge

The formwork and falsework in the construction of twin ribbed slab decks on a multi-span ecological bridge for a dual carriageway are presented. The bridge is situated in a valley plain which is crossed by small rivers and was designed principally with the environment in mind. The bridge length is over 356 m, and the width of the decks is 11.5 m. For the bridge works, a simple conventional falsework system was chosen with steel frames for the supports and steel rolled beams for the decks. The formwork was constructed in solid timber and plywood as multiple-use panels. The falsework was designed in order to build the two 10-span bridge decks in stages. The decks are continuous cast-in-situ prestressed concrete twin rib with spans of 30 m, 34 m and 45 m. An individual falsework system was designed, which was easy to move transversally following completion of each stage for one deck. After finishing each stage, for the second deck, the falsework was dismantled and used again in the next construction fronts. An individual arrangement for the falsework along with timber pilings was used to cross the biggest river. The formwork timber panels were used several times in the multistage bridge construction. The adopted falsework system is very simple, but it allowed the speedy construction of the two decks where there were severe time constraints.

Lean Construction in a Real Estate Project - A Case Study

Majority of all the construction projects experience cost and time overruns for reasons which are many times beyond the control of stakeholders.To overcome the same,the concept of lean integrated project delivery came into existence.Lean culture focuses on customer by empowering employees.It involves in converting waste into value by reducing waste,improving communication,and promoting teamwork integration through a common set of tools and techniques.Aim of lean construction is to achieve the affordable cost with optimum utilization of man,material and machinery.Wastes in construction industry which do not add value are supply in excess materials in inventory for raw material,work in progress,finished goods etc.Waiting for preceding activity,over processing and defects can be reduced through lean construction.This paper deals with lean construction techniques for identifying the waste in a construction project and eliminating the same..In this project estimation of a building is done to find cost of the project with respect to specifications and compared the traditional methods vis-a vis and lean construction techniques which can bring down the cost and with substantial improvement in quality aimed at satisfying the customer.

Research on Construction Process of Steel Box Girder Bridge and Its Stress Analysis

The paper introduce the construction method of large segment hosting and its difficulty, and drawing up corresponding liner and stress monitoring plan. The paper gives the calculation method of shear area for such a big cantilever thin-walled steel box girder section, namely the shear coefficient computation theory of Professor Hu Haichang, and the use of this shear area perfect beam element model, structure model and the experiment prove that the shell model is more consistent, given a certain reference for similar section project.

Performance evaluation of hybrid constructed wetlands for the treatment of municipal wastewater in developing countries

In developing countries,high cost of conventional wastewater treatment is a major hindrance in its application.Constructed wetlands(CWs)offer low-cost and effective solution to this issue.The current study aimed to evaluate an innovative maneuver of CWs i.e.hybrid flow constructed wetlands(HCWs)for municipal wastewater(MWW).The HCWs included two lab scale CWs;one horizontal and one vertical,in series.Local plant species were used.HCWs were operated in both,batch and continuous mode.Batch mode was used to(1)optimize detention time and(2)find pollutants removal efficiency.Continuous operation(at batch optimized retention time)was carried out for the evaluation of mass removal rate,r(g·m-2·d-1),volumetric rate constant,Kv(per day)and areal rate constant,Ka(m·d-1).Among two local plants tested,Pistia stratiotes gave better removal efficiency than Typha.Optimum detention time in HCWs was found to be 8 days(4+4 each).The optimum COD,BOD,TSS,TKN and P removal observed for Pistia stratiotes planted HCWs was 80%,84%,82%,71%and88%respectively.Effluent standards for COD,BOD and TSS were met at optimum conditions.The values of Kaand Kv demonstrated that more removal occurred in vertical flow as compared to horizontal flow CW.

Refined analysis and construction parameter calculation for full-span erection of the continuous steel box girder bridge with long cantilevers

To accurately control the full-span erection of continuous steel box girder bridges with complex cross-sections and long cantilevers, both the augmented finite element method(A-FEM) and the degenerated plate elements are adopted in this paper. The entire construction process is simulated by the A-FEM with the mesh-separation-based approximation technique, while the degenerated plate elements are constructed based on 3D isoparametric elements, making it suitable for analysis of a thin-walled structure. This method significantly improves computational efficiency by avoiding numerous degrees of freedom(DoFs) when analyzing complex structures. With characteristics of the full-span erection technology, the end-face angle of adjacent girder segments, the preset distance of girder segments from the design position, and the temperature difference are selected as control parameters, and they are calculated through the structural response of each construction stage. Engineering practice shows that the calculation accuracy of A-FEM is verified by field-measured results. It can be applied rapidly and effectively to evaluate the matching state of girder segments and the stress state of bearings as well as the thermal effect during full-span erection.

L2 Syntactic Alignment in the Reading-Writing Integrated Continuation Task: Evidence From Chinese EFL Learners’ Description of Motion Events

This study investigated how the mode in which the reading-writing integrated continuation task was conducted modulates the effects of second language(L2) syntactic alignment, through the English motion event construction with manner verbs. Ninety Chinese students were assigned to either of the two experimental groups or a control group, and they all experienced a pretest, an alignment phase and a posttest. In the alignment phase, the two experimental groups completed a reading-writing integrated continuation task but in different modes. For the multi-turn mode,participants reconstructed a picture story by continuing the episodes extracted from the story with one episode presented and continued at a time;for the single-turn mode, the first half of the same picture story was presented as a chunk, and then participants read and continued it. Results show that L2 learners aligned with the target structure in completing the story, and the alignment effect was retained in the posttest conducted after a delay of two weeks. Moreover, syntactic alignment was modulated by task mode with the multi-turn group exhibiting stronger immediate and longterm alignment effects. We conclude that the continuation task is a fruitful context for L2 structural alignment, and the magnitude of alignment effect hinges on interactive intensity.

非学历继续教育数字化教学资源库的建设

随着继续教育的重要性日益凸显,如何有效地提供教学资源成为一个关键问题。首先,分析了非学历继续教育的现状和发展趋势,阐述了数字化教学资源库的意义和作用;接着,提出了非学历继续教育数字化教学资源库的建设理念与目标,以及资源库的内容构建和技术支撑。同时,也探讨了资源库的应用与推广以及评估与持续改进等方面的问题。为构建高效、便捷、个性化的非学历继续教育数字化教学资源库提供理论和实践参考,以满足广大学习者的多样化需求,推动继续教育的快速发展。

双参数四重细分法

文章借助反向构造和倍乘平滑因子操作提出一种双参数四重细分法,运用生成多项式推导证明该四重细分方法的连续性,求解出满足C^(0)~C^(3)连续性的具体参数取值区间。该文通过数值实例分析各参数对形成曲线的影响,用动态的参数迭代过程描述曲线生成的变化细节。

以患者需求为导向的银屑病延续性护理方案的构建

目的以文献研究为基础,结合银屑病患者需求调查和德尔菲法的专家共识构建适应患者需求的银屑病延续性护理方案。方法采取文献研究法结合问卷调查法对150例银屑病患者进行延续性护理需求调查,基于调查结果讨论形成专家咨询表,通过对16名专家进行2轮咨询,修订并完善构建出银屑病患者的延续性护理方案。结果文献研究法从延续性护理的实施人员、具体内容、方式、频率、服务对象五个方面进行证据总结形成条目池,共纳入文献6篇,包括指南3篇、随机对照试验1篇、类试验1篇和专家共识1篇。延续性护理服务需求问卷调查希望形式主要集中在通过电话、短信随访、微信、QQ等互联网交流等方式,需求集中在用药、病情咨询、皮肤护理等方面指导。发放了16份有效问卷,两轮咨询共15位专家提出建议,Cr为0.85~1.00,平均为0.89;各条目CVj<0.25。最终构建出5个一级指标,27个二级指标及62个三级指标的银屑病患者延续性护理方案。结论基于患者需求的文献研究结合专家函询论证后构建的银屑病患者延续性护理方案有利于银屑病患者延续性护理措施的落地。

全面理解中国式社会治理现代化的四重维度

中国式社会治理现代化是中国式现代化事业的重要组成部分,是价值立场、思想方法、话语原则和实践旨归的有机统一。中国式社会治理现代化坚持人民至上的价值立场,在马克思主义对资本主义批判的理论基础上超越了西方纯粹工具理性导致单向度物质文明和维护资本利益的社会治理价值偏差,实现了“人”的价值理性的回归;秉持守正创新的思想方法,走出一条不同于西方社会治理模式和传统社会治理范式的中国特色社会主义社会治理现代化之路,拓展了社会治理现代化发展空间;坚持自信自立,不断推进社会治理话语创新,消除对西式话语的依赖,强化对社会治理现代化的体系化、学理化研究,做到既不封闭僵化,也不食洋不化;坚持共建共治共享,建设社会治理共同体,凝聚社会治理价值共识,健全社会治理体制机制,共享社会治理发展成果,筑牢社会治理道路根基。

教育强国建设中继续教育培育高素质农民的实践与思考

培育什么样的人是教育强国建设的核心要义之一。在教育强国的导向下,继续教育在高素质农民的培育目标、内容及方法等方面呈现显著特色,充分彰显继续教育的独有魅力与重大价值。伴随教育强国建设的不断深入推进,继续教育在高素质农民培育工作领域迎来了全新的发展机遇,同时也面临着诸多严峻挑战。以教育强国建设为总体目标,继续教育应通过一体化推进完善服务保障体系,借助多方共建协同育人机制,依靠精准培育探索教育培训特色,利用产教融合创新人才培养模式,持续提升高素质农民培育成效。

多跨预应力混凝土连续梁整体平移改造施工关键技术

宿迁古黄河老桥为(22.5+3×30+22.5)m四幅分离式连续梁桥,两侧为非机动车道桥,中间为机动车道桥。由于该桥位于生态保护区且梁体质量良好,为满足迎宾大道二期快速化改造需要,采取在不中断交通的前提下,通过交通导改先后将西侧和东侧机动车道桥分别往两侧整体平移3.25 m,再于中间修建新桥的改造方案。结合桥位处水文地质情况,采用在非机动车道桥外侧设置“钢板桩+过水钢管”围堰进行无水条件下的基础墩身拼宽施工。改造施工时,根据单侧机动车道桥支座处顶升荷载及梁底空间选配布置顶升千斤顶和步履器;通过有限元计算确定梁体顶升与平移施工过程中各支点竖向和横向位移偏差控制指标,采用PLC液压同步控制系统操控步履器与千斤顶交替顶升与平移,既能保证梁体整体顶升与平移的精度又能有效控制梁体应力突变;待梁体平移到设计位置后,拆除步履器和顶升千斤顶,复原垫石、支座及挡块。