Improving Portland Cement Concrete Mix Consistency and Production Rate through Two-St
Current time: 07-16-2018, 01:56 AM
Users browsing this thread: 1 Guest(s)
Author: ir_71
Last Post: ir_71
Replies 0
Views 1487

Improving Portland Cement Concrete Mix Consistency and Production Rate through Two-St
#1
Improving Portland Cement Concrete Mix Consistency and Production Rate through Two-Stage Mixing

Author: Tyson D. Rupnow, Vernon R. Schaefer, Kejin Wang, Benjamin L Hermanson | Size: 4.5 MB | Format: PDF | Publisher: National Concrete Pavement Technology Center | Year: 2007 | pages: 98

[Image: 65238947160173272798.jpg]


[Image: info.png]

Abstract:
A two-stage mixing process for concrete involves mixing a slurry of cementitious materials and water, then adding the slurry to coarse and fine aggregate to form concrete. Some research has indicated that this process might facilitate dispersion of cementitious materials and improve cement hydration, the characteristics of the interfacial transition zone (ITZ) between aggregate and paste, and concrete homogeneity. The goal of the study was to find optimal mixing procedures for production of a homogeneous and workable mixture and quality concrete using a two-stage mixing operation. The specific objectives of the study are as follows: (1) To achieve optimal mixing energy and time for a homogeneous cementitious material, (2) To characterize the homogeneity and flow property of the pastes, (3) To investigate effective methods for coating aggregate particles with cement slurry, (4) To study the effect of the two-stage mixing procedure on concrete properties, (5) To obtain the improved production rates. Parameters measured for Phase I included: heat of hydration, maturity, and rheology tests were performed on the fresh paste samples, and compressive strength, degree of hydration, and scanning electron microscope (SEM) imaging tests were conducted on the cured specimens. For Phases II and III tests included slump and air content on fresh concrete and compressive and tensile strengths, rapid air void analysis, and rapid chloride permeability on hardened concrete.

Key Words:
homogeneity—interfacial transition zone—mixing energy—mixing methods— rheological properties—two-stage mixing

[Image: Download.png]
***************************************
Content of this section is hidden, You must be registered and activate your account to see this content. See this link to read how you can remove this limitation:

http://forum.civilea.com/thread-27464.html
***************************************



[Image: password.png]
***************************************
Content of this section is hidden, You must be registered and activate your account to see this content. See this link to read how you can remove this limitation:

http://forum.civilea.com/thread-27464.html
***************************************



The expert doesn't think, the expert knows.
[-] The following 7 users say Thank You to ir_71 for this post:
  • kowheng, pedzaquino, Dell_Brett, toa011, oanm2000, tpipkpo, fer962933
Reply


Possibly Related Threads...
Thread Author Replies Views Last Post
The effects of aggregates characteristics on the performance of Portland cement ir_71 2 2,164 03-06-2015, 05:40 AM
Last Post: Veggeta
Cement and Concrete Composites journal bridgeengineer 0 1,439 02-02-2015, 07:03 PM
Last Post: bridgeengineer
CONCRETE & CEMENT SLABS aslam 0 1,276 08-19-2012, 03:21 AM
Last Post: aslam
Influence of Cellulose Ethers on the Kinetics of Early Portland Cement Hydration ir_71 0 1,100 02-24-2012, 07:23 PM
Last Post: ir_71
Portland Cement Pervious Concrete Pavement datagap 0 1,488 05-06-2011, 12:11 PM
Last Post: datagap



Users browsing this thread: 1 Guest(s)