Early-age Thermal Cracking, usually termed as Early Thermal Cracking is a phenomenon in concrete structures, caused by excessive Tensile Strain in a concrete section above the Tensile capacity of concrete as a result of restraining thermal contraction or due to differential temperature within the cross section. There are several factors that can influence ETC in … Read more
ACI METHOD OF MIX DESIGN – Absolute volume method Introduction In 1991,the American Concrete Institute(ACI) published guidaelines for normal, heavyweight and mass concrete mix design. The absolute volume method of mix design as described by ACI committee 211 is presented. It has the advantages of simplicity that it: Applies equally well with … Read more
Performance-Based Concrete Pavement Mix Design System Mix Design? It is the process of determining required and specifiable characteristics of a concrete mixture. Prescriptive approach (limits on materials). Performance approach (desirable characteristics). Mix design requirements are based on intended use, environment, etc.Mix design is the process of determining the quantities of concrete ingredients that meet the … Read more
Concrete Mix Design There are many methods of concrete mix design. But the British or American methods will not be applicable for our country, as the specific relationships constituting figures and tables are based on their materials. The IS 10262 recommends procedure for designing concrete mixes for general types of construction using the concreting materials … Read more
Fiber-Reinforced Concrete Historical Development Fibers have been used to reinforce brittle materials from time immemorial, dating back to the Egyptian and Babylonian eras, if not earlier. Straws were used to reinforce sun-baked bricks and mud-hut walls, horse hair was used to reinforce plaster, and asbestos fibers have been used to reinforce Portland cement mortars. Research … Read more
Concrete Basics A Guide To Concrete Practice Concrete Materials,Concrete Properties,Concrete Testing,Ordering Concrete,Proportioning and Mixing Concrete, Planning and Site Preparation,Transporting and Placing Concrete,Compacting Concrete,Finishing Concrete, Curing Concrete,Joints in Concrete,Hot and Cold Weather Concreting,Surface Finishes on Concrete, Defects in Concrete,Removing Stains from Concrete,Cracking in Concrete,Reinforced Concrete, Formwork CONCRETE is made by mixing: CEMENT WATER COARSE AND FINE … Read more
ACI Method of Mix Design Outline The most common method used in North America is that established by ACI Recommended Practice 211.1 Any mix design procedure will provide a first approximation of the proportions and must be checked by trial batches Local characteristics in materials should be considered The following sequence of steps should be … Read more
ACI Mix Design Practical Example Consider the following example: The 28-day compressive strength should be 7,000 psi. The slump should be between 3 and 4 in. and the maximum aggregate size should not exceed ¾ in. The coarse and fine aggregates in the storage bins are wet. The properties of the materials are as follows: … Read more
Effect Of ACI Concrete Mix Design Parameters On Mix Proportion & Strength The effect of different mix design parameters in predicting mix proportions by ACI method of concrete mix design and their strength attainment has been studied. The parametric study revealed that ACI method fails in rational proportioning of fine aggregate content where coarse aggregate … Read more