STUDY ON THE PREDICTION FORMULA FOR TIME-DEPENDENT STRAIN OF CONCRETE : Prediction formula of drying shrinkage strain

Abstract

In the 帥 一 e ・ based desi 帥 r s 啣 cra 曲 g in buildi 皿 ＆ the rellable mathe 瓶 ical model for prediCting shrinkage

Agent‐based modeling of super‐long‐term maintenance processes for RC building groups: Stochastic study of risks of building groups by super‐long‐term combined deterioration Part 2

“…First, we calculate the number of drying-shrinkage cracks in walls by substituting the final values of drying-shrinkage strains into the prediction equation by In et al 25 At this time, in order to evaluate the fluctuation, we use a coefficient variation of 0.3 in the normal distribution in accordance with the residuals of the prediction equation of the creep strain, the drying-shrinkage strain, and the elastic modulus by Sato et al [26][27][28] We also assume the following: (a) the number of cracks in the slab on the 10th floor or above is equivalent to it in the slab on the 10th floor, (b) cracks penetrate walls in the vertical direction, and (c) in the concrete around cracks, the equivalent bond-loss area 29 loses its airtightness and alkalis with no relation to the crack width.…”

“…Specifications for structuresCover depths are regulated as if outer depths are larger than inner depths, and variations of cover depths are set by standard deviation of 10 mm.9 b Cracks are induced in all crack-inducing joints. Specifications for analyses of preinduced cracks are follows: (a) water cement ratio of concrete is set by relations between water cement ratio and nominal strength of ready-mixed concrete in Kanto area44 ; (b) unit water content, bulk volume of coarse aggregate per unit volume of concrete, and solid content of coarse aggregate are set by Architectural Institute of Japan guidelines for the mix proportion of concrete 45 ; (c) cement type is Ordinary Portland Cement only; (d) adoption rates of gravel and crushed stones are both 0.546 ; (e) when durability-preferred building owners adopt crushed stones, crushed lime stones are used; and (f) creep coefficient and drying shrinkage of concrete are calculated by Sato's method26,27 under condition that removal age of supports is 28 d and wet cure is completed in 5 d.…”

Evaluation of Performance of Mortar Using Granulated Paper Sludge Ash for Precast Material

“…Fig.11 Comparisons of drying shrinkage strain with time between predictions and test measurements. JSCE and AIJ represent equation of Japan Society of Civil Engineers 6) and Architectural Institute of Japan 7) , respectively.…”

“…Comparison results of drying shrinkage strain between experiments and predictions by AIJ equation. AIJ represent equation of Architectural Institute of Japan7) .…”