水泥注浆振冲碎石桩在基础工程中的应用

结合一工程实例 ,对应用水泥注浆振冲碎石桩处理建筑软土地基的设计方法及施工工艺进行探讨 ,并对施工效果进行评述     

高压旋喷桩在软基施工中的质量控制

高压旋喷桩是利用钻机先钻至地基设计标高,再用高压泵将不小于20MPa的水泥浆液从特制钻头上的喷嘴喷出,同时按预定的工艺参数旋转提升钻杆,由下至上进行旋喷,形成连续的柱状加固体,这就是旋喷桩。具有投资省、速度快、加固效果好等优点,适用于处理淤泥、淤泥质土、软塑或可塑性土、粉土、砂土、素填土和碎石土等地基。本文叙述了高压旋喷桩加固软基工程的质量全过程控制要点。     

振冲法在地基处理中的应用

振冲法是利用振冲器强烈震动和压力水冲贯入到土层深处,提高地基强度的加固技术。作者结合工程实际对振冲法加固地基的方法进行了详细的论述分析,并通过工程的实施,证明了该处理方式对地基的加固效果是明显的,可供借用。     

高压旋喷桩在地基加固工程中施工质量的控制

通过某高层建筑地基基础加固的工程实例,介绍了高压旋喷桩的加固原理,结合工程实践详细阐述了在地基基础加固中采用主动控制为主、被动控制为辅、两种手段相结合的动态控制方法来控制高压旋喷桩的质量以及施工前、施工过程中的预防措施。结果表明,采用高压旋喷桩处理地基可取得良好的加固效果及较好的技术效果。     

振动沉管CFG桩复合地基在饱和软土地基工程的应用

介绍了使用CFG桩复合地基处理饱和软土地基工程实例,论述了采用振动沉管制桩、跳打等施工工艺控制施工质量的方法．经检测,采用该复合地基加固饱和软土地基效果好,成本低,有一定经济效益．     

水泥搅拌桩在高速公路软土地基施工质量控制

水泥搅拌桩是近几年用于加固软粘土地基的一种常用方法,结合工程实例,详细介绍了水泥搅拌桩的施工工艺和实验检测方法,质量控制的注意事项,对应用效果作了简要评述.     

振动沉管CFG桩复合地基在漫滩相地基工程的应用

介绍了使用CFG桩复合地基处理漫滩相地基工程实例,论述了采用振动沉管制桩、跳打等施工工艺控制施工质量.经检测,采用该复合地基加固漫滩相地基效果好,成本低,有一定经济效益.     

挤密碎石桩的加固地基施工与检测

介绍等能量、等变形夯扩挤密碎石桩加固高填方路基地基的工艺原理、工艺流程和采用静荷载试验进行检测的方法及结果     

浅析高速公路软土路基的特点及处理方法

主要对高速公路软土路基的特点及处理方法进行了分析.首先概述了高速公路软土路基的特点,然后分析了高速公路软土路基常见处理方法,最后探讨了振冲碎石桩复合地基处理方法的特点和施工工艺.     

水泥粉喷桩在公路工程软基处理的应用

粉喷桩加固软土地基是基于水泥加固土的物理化学反应，形成复合地基，是桩和土共同承担上部结构传来的荷载，达到提高其复合地基承载力的目的；根据公路工程对地基条件的要求，结合地区软基特点，从设计、施工、质量控制方面介绍了连云港地区公路工程采用水泥粉喷桩加固软土地基的方法。     

Connected Learning and the Foundations of Psychometrics: A Rejoinder

This paper continues an exchange between its author and Andrew Davis. Part I addresses the attribution and ontological status of mental constructs and argues that philosophical work on these topics does not undermine high stakes testing. Part II examines the significance for testing of the connectedness of meaningful learning. Part III addresses the high stakes in high stakes testing in connection with the risk entailed by limited scoring reliability. It concludes that there is no straightforward relationship between the magnitude of what is at stake for students and teachers and the threshold of acceptable reliability in scoring.     

Devising inequality: a Bernsteinian analysis of high‐stakes testing and social reproduction in education

High‐stakes, standardized testing has become the central tool for educational reform and regulation in many industrialized nations in the world, and it has been implemented with particular intensity in the United States and the United Kingdom. Drawing on research on high‐stakes testing and its effect on classroom practice and pedagogic discourse in the United States, the present paper applies Bernstein’s concept of the pedagogic device to explain how high‐stakes tests operate as a relay in the reproduction of dominant social relations in education. This analysis finds that high‐stakes tests, through the structuring of knowledge, actively select and regulate student identities, and thus contribute to the selection and regulation of students’ educational success.     

Raising the Stakes of Test Administration: The Impact on Student Performance on the National Assessment of Educational Progress

This article briefly reviews the current discussion of the effects of test administration conditions (i.e., testing stakes), and the motivational levels associated with them, on achievement test performance. The non-experimental study presented here investigates whether differences in test administration conditions and presumed levels of motivation engendered by different testing environments affect student performance on National Assessment of Educational Progress (NAEP) administrations. The testing conditions under study are the "low-stakes" environment of the current NAG administration and a higher stakes environment typified by many state assessment programs. The results suggest that in comparison to a "moderate-stakes" testing environment NAEP does not seriously underestimate achievement levels. However, the results cannot lead to the conclusion that student achievement is unrelated to testing stakes. Nor can one conclude that substantially raising the stakes of NAEP would not be accompanied by an increase in achievement scores.     

无损检测技术在石质文物保护中的应用

概述了无损检测技术在探测石质文物的风化程度、评价岩石加固效果、探测裂隙分布和裂缝灌浆深度、探测石窟渗水原因、研究彩绘和壁画的颜色以及分析颜料成分等方面的应用,并提出了无损检测技术在石质文物保护工作中应用的几点认识.     

HEIGHTENED TEST ANXIETY AMONG YOUNG CHILDREN: ELEMENTARY SCHOOL STUDENTS’ ANXIOUS RESPONSES TO HIGH‐STAKES TESTING

This study explored differences in test anxiety on high‐stakes standardized achievement testing and low‐stakes testing among elementary school children. This is the first study to directly examine differences in young students’ reported test anxiety between No Child Left Behind (NCLB) achievement testing and classroom testing. Three hundred thirty‐five students in Grades 3 through 5 participated in the study. Students completed assessments of test anxiety following NCLB testing and typical classroom testing. Students reported significantly more overall test anxiety in relation to high‐stakes testing versus classroom testing on two measures of test anxiety, effect sizes r = ?.21 and r = ?.10. Students also reported significantly more cognitive (r = ?.20) and physiological (r = ?.24) symptoms of test anxiety in relation to high‐stakes testing. This study adds to the test anxiety literature by demonstrating that students experience heightened anxiety in response to NCLB testing.     

挤扩支盘灌注混凝土桩在工程中的应用与分析

厂房车间跨度大、荷载大及抗震要求对桩基础应用提出了较高要求。文章通过对挤扩支盘混凝土灌注桩的计算、测试、受力分析及在工程实践中的应用研究,较好地解决了工程基础的要求,取得了明显的经济效益。     

Can high stakes testing leverage educational improvement? Prospects from the last decade of testing and accountability reform

This article examines major trends in testing and accountability reform in the United States over the past decade. The review covers the apex and decline of the national experimentation with a range of alternative assessments and the rise of test-based accountability as a central policy initiative. These trends signify that testing has become a widely utilized instrument for educational reform in America. Research on these trends indicates that high stakes testing does motivate teachers and administrators to change their practices, yet the changes they motivate tend to be more superficial adjustments in content coverage and test preparation activities rather than promoting deeper improvements in instructional practice. Further, the information provided by large scale assessments is primarily useful to measure school and system progress, but of more limited utility for instructional guidance. Most problematic is that the high stakes testing system in America has been repeatedly promoted as a substantive reform in itself. However, high stakes testing is a relatively weak intervention because, while it reveals shortcomings, it does not contain the guidance and expertise to inform response. The article concludes with suggestions on how to capitalize on the strengths of high stakes testing while minimizing its shortcomings.     

The construction of the ‘ideal pupil’ and pupils’ perceptions of ‘misbehaviour’ and discipline: contrasting experiences from a low‐socio‐economic and a high‐socio‐economic primary school

This paper examines the effect of school social class composition on pupil learner identities in British primary schools. In the current British education system, high‐stakes testing has a pervasive effect on the pedagogical relationship between teachers and pupils. The data in this paper, from ethnographic research in a working‐class school and a middle‐class school, indicate that the effect of the ‘testing culture’ is much greater in the working‐class school. Using Bernsteinian theory and the concept of the ‘ideal pupil’, it is shown that these pupils’ learner identities are more passive and dominated by issues of discipline and behaviour rather than academic performance, in contrast to those in the middle‐class school. While this study includes only two schools, it indicates a potentially significant issue for neo‐liberal education policy where education is marketised and characterised by high‐stakes testing, and schools are polarised in terms of social class.     

Student-Centered Teaching in a Standards-Based World: Finding a Sensible Balance

This paper addresses a tension that existsin the present reform movement in scienceeducation. This is the tension between rigorand accountability through standards,benchmarks, and high stakes testing on theone hand and more progressive,student-centered approaches to teaching andlearning on the other.     

High Stakes Testing and the Structure of the Mind: A Reply to Randall Curren

'High stakes testing' is to be understood as testing with serious consequences for students, their teachers and their educational institutions. It plays a central role in holding teachers and educational institutions to account. In a recent article Randall Curren seeks to refute a number of philosophical arguments developed in my The Limits of Educational Assessment against the legitimacy of high stakes testing. In this reply I contend that some of the arguments he identifies are not mine, and that others survive his critique.