详情

Lightweight Concrete Modification Factor for Shear Friction

项目名称：	Lightweight Concrete Modification Factor for Shear Friction
摘要：	This project is aimed at studying the influence of aggregate type on direct shear transfer across an interface of concretes cast at different times. The shear friction design concept is applicable in conditions where direct shear must be transferred across a structural concrete plane or interface, such as an existing crack or an interface between dissimilar materials or concretes cast at different times. Shear friction provisions are commonly used in the design of precast-prestressed concrete elements and connections in building and/or bridge structures including corbels, dapped double tees, beam bearings, and diaphragms. These types of connections are critical because there is little or no redundancy. Data used to develop shear friction provisions in both the ACI 318 Code and the PCI Design Handbook are predominantly from experiments with specimens constructed of normal weight concrete (NWC). Only a limited number of studies have been performed on lightweight concrete (LWC), and particularly for conditions with concrete surfaces cast at different times. This condition may exist, however, due to precast plant practices and the increasing use of self-consolidating concrete (SCC), and where projecting elements might be cast after the underlying concrete has partially hardened. Alternatively, projecting elements might be cast in advance and inserted into the fresh concrete when the main member is cast, resulting in a similar condition. It should also be noted that the influence of SCC on the interface shear has not been thoroughly studied. In summary, lack of LWC test data and clear and consistent design provisions underscore the need for a systematic approach to isolate and examine the influence of factor λ on the interface friction so that it can be applied clearly and confidently in shear friction design.
状态：	Completed
资金：	30000.00
资助组织：	Precast/Prestressed Concrete Institute
执行机构：	Center for Infrastructure Engineering Studies
开始时间：	20110815
实际结束时间：	20120814
主题领域：	Bridges and other structures；Design；Highways；I30: Materials