混凝土早期断裂力学行为

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发布时间：2022-03-05

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IMPROVED PRODUCTION OF ADVANCED CONCRETE STRUCTURES . IPACS
Background
Research and practical experience show that the quality and lifetime of concrete structures largely
depend on the curing conditions in the concrete's early life, as inadequate curing leads to malfunction
and cracking. A major source of deleterious cracking already in the construction stage is the
occurrence of stresses in the hardening concrete due to restr ained volume change related to hydration
temperatures and shrinkage phenomena. It is thus of utmost importance, especially regarding new high
performance concrete, that the proper execution conditions are maintained throughout the construction
period by avoiding the premature cracking.
Objective of project
Main goal ofIPACS is to eval uate, integrate and extend the existing knowledge about early age
concrete crack prediction in engineering practice yielding the following benefits:
●Contractors and designers will have new and more reliable engineering instruments enabling them to
predict and to optimise the technical effect and cost of alternative designs and execution procedures -
all in the process of ful fling the quality requirements set up by the owners or the community (codes).
●Reduced costs because of the present tendency to specify costly but unecessarily rigorous crack
criteria will be avoided.
●Owners will have access to improved means of specifying and controlling desired quality
requirements regarding serviceability and service life of their structures.
●Reduced maintenance costs and increase of service lifetime.
Main 1asks and investigations in IPACS and ouput from the project:
●Hydr ation and vol ume changes - To acquire data for the modelling of properties ofa
number of currently used concrete types.
●Mechanical properties- Testing and modelling of mechanical properties.
●Behaviour of structures - Computer modelling of structural behaviour.
●Field tests- To check and improve the models of the previous tasks in full-scale tests.
●Expert System.
The Expert System synthesises the results from the project into a robust engineering tool for planning
and control of the production of concrete structures. It contains modules of varying simp licity, which
can be used in all the phases of a construction project fom pre-design to maintenance
Project Parners:
See earlier page
Project Co-ordinator:
Dr Mats Emborg - Betongindustri AB (Heidelberger Zement North Europe) (SE)
Dr Hans-Erik Granm/Mr Mats Oberg - Cementa AB (Heidelberger Zement North Europe)(SE)
Disclaimer
The author/authors and producer of this repont have used their best effort in preparing this report. Theses efforts
include the dewelopmant, resarch and testing of the theonies and progams to determine their efectivenes. The
author/authors and produeer make no warranty of any kind, expressed or implied, with regard to these progams
or documentation contained in this report. The author/ authors and publisher shall not be liable in any event for
incidental or consequential damage in conection with, or arising out of, the furnishing performance, or use of
these programs.
Editrial/production supervision: Prof. Lennart Elfgren
Cover design:
Hans Hedlund
Prepress material:
Printed and published by
Lulea University of Technology,
Department of Civil and Mining Enginering,
Division of Stuctural Engineering
SE-971 87 Lulea, Sweden