Research data have indicated that the measured modulus of elasticity of high-strength concrete can vary significantly from calculated values based on unit weight and concrete compressive strength. Factors included in selecting concrete mix proportions have included availability of constituent materials, desired workability, and effects of temperature rise. Depending on the appropriate application, mix proportions for high-strength concrete generally have been based on achieving a required compressive strength at a specified age, many times beyond the traditional 28 days. To ensure that required concrete strengths and other desired properties would be obtained, trial mixtures are an essential part of the process. Items to be considered in selecting materials include characteristics of cement and supplementary cementitious materials, aggregate properties, and the effects of chemical admixtures, particularly with respect to their water reduction and hydration controlling capabilities. In reality, all changes that take place at or above 55 MPa (8000 psi) represent a process which starts with the lower strength concretes and continues into the highstrength realm. Although 55 MPa (8000 psi) was selected as the current lower limit, it is not intended to imply that any drastic change in material properties or in production techniques occurs at this compressive strength. In many markets today, concrete having a specified compressive strength in excess of 69 MPa (10,000 psi) is routinely produced on a daily basis. Today, high-strength concrete is defined as concrete with a specified compressive strength of 55 MPa (8000 psi) or higher. In the 1950s, concrete with a compressive strength of 34 MPa (5000 psi) was considered high strength. The objective of the document is to present state-of-the-art information on concrete with strengths in excess of about 55 MPa (8000 psi), but not including concrete made using exotic materials or techniques. Estimated publication time for the new document is early 2006. This synopsis is based on a full report on high-strength concrete to be published by ACI Committee 363 (High-Strength Concrete). One of the primary objectives of ACI Committee 363 during the last few years has been to update and republish document 363R, High-Strength Concrete. With the increased knowledge that has been gained with respect to material availability, design methodology, and construction techniques, the feasible realm of high-strength concrete applications has grown dramatically. During this period, many notable changes have occurred and continue to occur in the area of high-strength concrete technology, including the definition of high-strength concrete itself. ![]() Symbols, abbreviations, or full names for units of length,Īrea, mass, pressure, and other types.Keywords: applications concrete design economics high-strength materials production properties proportionsĪlthough highstrength concrete is often times still considered a relatively new material, its development has been gradual and continual over the last 50 years. ![]() You can find metric conversion tables for SI units, as wellĪs English units, currency, and other data. Water has a viscosity of 0.0089 poise at 25 ☌, or 1 centipoise at 20 ☌.Ĭonversion calculator for all types of measurement units. A centipoise is one millipascal second (mPa So 1 millipascal-second = 10 -3 pascal-second.Ī unit of dynamic viscosity in the CGS system of units. The SI prefix "milli" represents a factor of mPa-s to pound-force second/square foot.You can do the reverse unit conversion fromĬentipoise to mPa-s, or enter any two units below: Enter two units to convert From:
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