کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
260196 503654 2011 13 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Super absorbing polymers as an internal curing agent for mitigation of early-age cracking of high-performance concrete bridge decks
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی عمران و سازه
پیش نمایش صفحه اول مقاله
Super absorbing polymers as an internal curing agent for mitigation of early-age cracking of high-performance concrete bridge decks
چکیده انگلیسی

High-performance concrete (HPC) with low w/b-ratio experiences a considerable chemical shrinkage and self-desiccation during its hydration process, leading to a rather high autogenous shrinkage deformation during hardening. In case the free deformation of the concrete is prevented, internal stresses are introduced, which can lead to premature cracks. These early-age cracks can severely affect the durability of a concrete structure. By adding super absorbing polymers (SAP) into the HPC as an internal curing agent, and by adding additional curing water to the concrete mixture, the chemical shrinkage and the self-desiccation during hydration of the concrete is counteracted and thus the autogenous shrinkage of the HPC can be significantly reduced. Unfortunately, this process of internal curing also has some disadvantageous effects on the mechanical properties. In search of an optimization of the internal curing process, an extensive experimental program was performed on HPC, using different degrees of internal curing, to assess the mechanical and thermal properties of the HPC, and to evaluate the effectiveness of the performed curing. The goal is to obtain a maximal autogenous shrinkage reduction and a minimal strength reduction. The resulting effect on the early-age cracking risk is simulated by means of finite element calculations. The simulations also include thermal stress development due to the heat of hydration. In case 70 kg/m3 of internal curing water is provided via the SAP, an optimal reduction of the cracking risk is noticed, mainly caused by the autogenous shrinkage reduction and the appearing expansive deformation peak directly after setting takes place.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Construction and Building Materials - Volume 25, Issue 1, January 2011, Pages 1–13
نویسندگان
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