Dynamic Assessment of Shear Connection Conditions in Slab-Girder Bridges by Kullback-Leibler Distance

<p>A requirement for heavier vehicular transport on the Norwegian road network has resulted in a demand for increased bearing capacity for many of the older bridges in the country. Many of the bridges that have been found to have insufficient capacity against present-day demands are steel girder bridges with concrete slabs without a shear connection between steel and concrete. There is a large number of bridges of this type in Norway and the paper presents strengthening of two of those, in Aust-Agder county in the south of the country. These bridges are approximately 30 m long, single span. The bearing capacity has been upgraded by installing composite action between the steel girders and the concrete slab using coiled pins, in conjunction with thickening of the bottom flange of the steel girders. To obtain composite action, the pins are fitted to tightly drilled holes through the top flange of girders up into the concrete slab. Coiled pins have not been used much for bridge applications. In the work presented, the method has been found to have advantages in terms of cost and workability. Furthermore, the method has benefits when viewed from an environmental standpoint, since it allows strengthening of existing non-composite bridges using relatively little new material, and minimizes traffic disruptions.</p>

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Dynamic assessment of shear connectors in slab–girder bridges

Engineering Structures ◽

10.1016/j.engstruct.2006.09.014 ◽

2007 ◽

Vol 29 (7) ◽

pp. 1475-1486 ◽

Cited By ~ 35

Author(s):

Yong Xia ◽

Hong Hao ◽

Andrew J. Deeks

Keyword(s):

Dynamic Assessment ◽

Shear Connectors ◽

Girder Bridges

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Testing of composite girders with coiled spring pin shear connectors

10.2749/ghent.2021.1700 ◽

2021 ◽

Author(s):

Robert Hällmark ◽

Rasoul Nilforoush ◽

Victor Vestman ◽

Peter Collin

Keyword(s):

Composite Structures ◽

Bending Moment ◽

Moment Capacity ◽

Shear Connectors ◽

Shear Connection ◽

Girder Bridges ◽

Coiled Spring ◽

Cost Efficient ◽

Structural Parts ◽

Existing Bridges

<p>Today, steel girder bridges with concrete deck slabs are generally constructed as steel-concrete composite structures, to utilize the material and the structural parts in an efficient way. However, many existing bridges constructed before the early 1980´s were designed without shear connectors at the steel-concrete interface. With increasing traffics loads and higher amount of load cycles, there is sometimes a need to strengthen these bridges. One way to increase the bending moment capacity is to create composite action by post-installation of shear connectors. The authors have studied the concept of strengthening by post-installed shear connectors, with a focus on a connector called coiled spring pin. This paper presents the results from the first beam tests performed with this kind of shear connector. In line with the previous push-out tests, the test results indicate a very ductile shear connection, with a potential to be a material- and cost-efficient strengthening alternative.</p>

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Dynamic Assessment Language Tasks and the Prediction of Performance on Year-End Language Skills in Preschool Dual Language Learners

American Journal of Speech-Language Pathology ◽

10.1044/2019_ajslp-19-00120 ◽

2020 ◽

Vol 29 (3) ◽

pp. 1226-1240

Author(s):

Janet L. Patterson ◽

Barbara L. Rodríguez ◽

Philip S. Dale

Keyword(s):

Head Start ◽

Language Learners ◽

Language Impairment ◽

Dual Language ◽

Dynamic Assessment ◽

Dual Language Learners ◽

Achievement Testing ◽

Potential Applications ◽

Language Screening ◽

Relationship Of

Purpose Early identification is a key element for accessing appropriate services for preschool children with language impairment. However, there is a high risk of misidentifying typically developing dual language learners as having language impairment if inappropriate tools designed for monolingual children are used. In this study of children with bilingual exposure, we explored performance on brief dynamic assessment (DA) language tasks using graduated prompting because this approach has potential applications for screening. We asked if children's performance on DA language tasks earlier in the year was related to their performance on a year-end language achievement measure. Method Twenty 4-year-old children from Spanish-speaking homes attending Head Start preschools in the southwestern United States completed three DA graduated prompting language tasks 3–6 months prior to the Head Start preschools' year-end achievement testing. The DA tasks, Novel Adjective Learning, Similarities in Function, and Prediction, were administered in Spanish, but correct responses in English or Spanish were accepted. The year-end achievement measure, the Learning Accomplishment Profile–Third Edition (LAP3), was administered by the children's Head Start teachers, who also credited correct responses in either language. Results Children's performance on two of the three DA language tasks was significantly and positively related to year-end LAP3 language scores, and there was a moderate and significant relationship for one of the DA tasks, even when controlling for age and initial LAP3 scores. Conclusions Although the relationship of performance on DA with year-end performance varies across tasks, the findings indicate potential for using a graduated prompting approach to language screening with young dual language learners. Further research is needed to select the best tasks for administration in a graduated prompting framework and determine accuracy of identification of language impairment.

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School-Based Speech-Language Pathologists' Adherence to Practice Guidelines for Assessment of English Learners

Language Speech and Hearing Services in Schools ◽

10.1044/2020_lshss-20-00037 ◽

2020 ◽

pp. 1-12

Author(s):

Virginia L. Dubasik ◽

Dubravka Svetina Valdivia

Keyword(s):

Professional Practice ◽

Practice Guidelines ◽

Case History ◽

English Learners ◽

Online Survey ◽

Dynamic Assessment ◽

Federal Legislation ◽

Assessment Practices ◽

Speech Language Pathologists ◽

School Based

Purpose The purpose of this study was to ascertain the extent to which school-based speech-language pathologists' (SLPs) assessment practices with individual English learners (ELs) align with federal legislation and professional practice guidelines. Specifically, we were interested in examining SLPs' use of multiple tools during individual EL assessments, as well as relationships between practices and number of types of training experiences. Method School-based SLPs in a Midwestern state were recruited in person or via e-mail to complete an online survey pertaining to assessment. Of the 562 respondents who completed the survey, 222 (39.5%) indicated past or present experience with ELs, and thus, their data were included in the analyses. The questionnaire solicited information about respondent's demographics, caseload composition, perceived knowledge and skills and training experiences pertaining to working with ELs (e.g., graduate school, self-teaching, professional conferences), and assessment practices used in schools. Results The majority of respondents reported using multiple tools rather than a single tool with each EL they assess. Case history and observation were tools used often or always by the largest number of participants. SLPs who used multiple tools reported using both direct (e.g., standardized tests, dynamic assessment) and indirect tools (e.g., case history, interviews). Analyses revealed low to moderate positive associations between tools, as well as the use of speech-language samples and number of types of training experiences. Conclusions School-based SLPs in the current study reported using EL assessment practices that comply with federal legislation and professional practice guidelines for EL assessment. These results enhance our understanding of school-based SLPs' assessment practices with ELs and may be indicative of a positive shift toward evidence-based practice.

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Dynamic Assessment With Bilinguals: A Focus on Increasing Clinicians' Confidence

Perspectives on Communication Disorders and Sciences in Culturally and Linguistically Diverse Populations ◽

10.1044/cds22.3.112 ◽

2015 ◽

Vol 22 (3) ◽

pp. 112-121 ◽

Cited By ~ 4

Author(s):

Brenda K. Gorman

Keyword(s):

Standardized Tests ◽

Dynamic Assessment ◽

English Speakers ◽

Bilingual Children ◽

Assessment Practices ◽

Speech Language Pathologists ◽

Idea 2004 ◽

Disabilities Education Act ◽

Effective Dynamic ◽

Education Act

Speech-language pathologists (SLPs) are obligated to judiciously select and administer appropriate assessments without inherent cultural or linguistic bias (Individuals with Disabilities Education Act [IDEA], 2004). Nevertheless, clinicians continue to struggle with appropriate assessment practices for bilingual children, and diagnostic decisions are too often based on standardized tests that were normed predominately on monolingual English speakers (Caesar & Kohler, 2007). Dynamic assessment is intended to be a valid and unbiased approach for ascertaining what a child knows and can do, yet many speech-language pathologists (SLPs) struggle in knowing what and how to assess within this paradigm. Therefore, the aim of this paper is to present a clinical scenario and summarize extant research on effective dynamic language assessment practices, with a focus on specific language tasks and procedures, in order to foster SLPs' confidence in their use of dynamic assessment with bilingual children.

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