Effect and Action Mechanism of Superplasticizer on Foamed Cement

2014 ◽  
Vol 548-549 ◽  
pp. 1659-1662
Author(s):  
Chuan Wei Du ◽  
Guo Zhong Li

The ordinary Portland cement was used to prepare foamed cement by the chemical foaming method. In this paper, the effect of superplasticizer on the water absorption and softening coefficient of foamed cement has been studied. The results show that the superplasticizer could improve foam structure, reduce the water absorption, and enhance the compressive strength and softening coefficient. The water resistance could be improved. When the dosage of superplasticizer was 0.3% (the quality of cement), compared with blank sample, the water absorption reduced 27.9%. When the softening coefficient was 0.68, softening coefficient increased 19.2%. The action mechanism of superplasticizer has been explored.

2012 ◽  
Vol 476-478 ◽  
pp. 1585-1588
Author(s):  
Hong Pan ◽  
Guo Zhong Li

The comprehensively modified effect of cement, VAE emulsion and self-made acrylic varnish on mechanical and water-resistant properties of gypsum sample was investigated and microstructure of gypsum sample was analyzed. Experimental results exhibit that absolutely dry flexural strength, absolutely dry compressive strength, water absorption and softening coefficient of gypsum specimen with admixture of 10% ordinary Portland cement and 6% VAE emulsion and acrylic varnish coated on its surface can respectively reach to 5.11MPa , 10.49 MPa, 8.32% and 0.63, respectively.


2013 ◽  
Vol 662 ◽  
pp. 327-330 ◽  
Author(s):  
Chuan Wei Du ◽  
Guo Zhong Li

The rapid hardening sulphoaluminate cement was used to prepare foamed cement by the chemical foaming method. The impact of organic and inorganic waterproofing agent on the water absorption, mechanical strength and softening coefficient of foamed cement were studied. The results showed that adding waterproofing agent could improve its foam structure and reduce the water absorption, improve its mechanical strength and softening coefficient, thus improving its water resistance; Organic waterproof agents had a better performance than inorganic waterproof agents. The mechanisms of action of different waterproofing agent were explored.


2013 ◽  
Vol 6 (1) ◽  
pp. 50-61
Author(s):  
Amer M. Ibrahem ◽  
Shakir A. Al-Mishhadani ◽  
Zeinab H.Naji

This investigation aimed to study the effect of nano metakaolin ( NMK ) on some properties (compressive strength ,splitting tensile strength & water absorption ) of concrete. The nano metakaolin (NMK) was prepared by thermal activation of kaolin clay for 2 hours at 750 Ċ. The cement used in this investigation consists of ordinary Portland cement (OPC). The OPC was partially substituted by NMK of ( 3, 5 & 10%) by weight of cement. The C45 concrete was prepared , using water/cement ratio ( W/c) of (0.53) .The Water absorption was tested at 28 days while the tests (compressive strength ,splitting tensile strength) were tested at ages of (7, 28, 60,& 90) days . The compressive strength and splitting tensile strength of concrete with NMK were higher than that of reference concrete with the same W/c ratio.The improvement in the compressive strength when using NMK was (42.2, 55.8 , 63.1% ) at age 28 days for ( 3%, 5%, &10% ) replacement of NMK respectively whereas the improvement in the splitting tensile strength was (0% , 36% & 46.8 %) at age of 28 days when using (3%, 5%, &10% ) NMK respectively. The improvement in the water absorption was (16.6%, 21.79%, &25.6 ) when using (3, 5, &10% )NMK.


2021 ◽  
Vol 47 (2) ◽  
pp. 216-224
Author(s):  
Noorafizah Binti Murshid ◽  
Nor Amani Filzah Binti Mohd Kamil ◽  
Aeslina Abdul Kadir ◽  
Noor Faiza Binti Roslee ◽  
Abdul Rahim Jalil

In Malaysia, the current practise in treatment of petroleum sludge (PS) is by using incineration and the ash produce required further treatment for safely disposal into landfill. This process require high cost and treatment of raw sludge by using solidification/stabilization method was introduce. In this study, ordinary Portland cement was used as binder. This study focuses on physical properties (compressive strength, density test and water absorption) of S/S matrices and leaching behaviour (SPLP). Results shows adds up to of 30% PS gives results on strength which comply with minimum landfill dispose limit. Correlation between strength and density in regression coefficient of 80.99% and correlation between strength and water absorption shows strong regression of 93.12%. Leaching behaviours on 28 th day of curing showed the similar trend as on 7th day of curing. All heavy metals concentration in leaching test were below the USEPA standard except for Nickel and Chromium. Even though these two metals were exceeded the standard, Portland cement was capable to encapsulate Ni and Cr in mixture and reduce the concentration of 87% and 69% (PS 40%), respectively, compare to concentration in raw sludge. As, conclusion S/S method can be an alternative disposal method for raw sludge.


2020 ◽  
Vol 857 ◽  
pp. 83-88
Author(s):  
Ikram F. Ahmed Al-Mulla ◽  
Ammar S. Al-Rihimy ◽  
Mushriq F. Al-Shamaa

From the sustainability point of view a combination of using water absorption polymer balls in concrete mix produce from Portland limestone cement (IL) is worth to be perceived. Compressive strength and drying shrinkage behavior for the mixes of concrete prepared by Ordinary Portland Cement (O.P.C) and Portland limestone cement (IL) were investigated in this research. Water absorbent polymer balls (WAPB) are innovative module in producing building materials due to the internal curing which eliminates autogenous shrinkage, enhances the strength at early age, improve the durability, give higher compressive strength at early age, and reduce the effect of insufficient external curing. Polymer balls (WAPB) had been used in the mixes of this research to provide good progress in compressive strength with time. Water absorption polymer balls have the ability to absorb water and after usage in concrete it will spill it out and shrink leaving voids of their own diameter before shrinking that lead to provide internal curing. The required quantity of water for the mixes were reduced due to the addition of water from the absorption polymers. Mixes produced from Portland limestone cement in this research show drying shrinkage results and compressive strength results lower than mixes made from ordinary Portland cement.


2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Jijo James ◽  
P. Kasinatha Pandian ◽  
K. Deepika ◽  
J. Manikanda Venkatesh ◽  
V. Manikandan ◽  
...  

The study involved investigating the performance of ordinary Portland cement (OPC) stabilized soil blocks amended with sugarcane bagasse ash (SBA). Locally available soil was tested for its properties and characterized as clay of medium plasticity. This soil was stabilized using 4% and 10% OPC for manufacture of blocks of size 19 cm × 9 cm × 9 cm. The blocks were admixed with 4%, 6%, and 8% SBA by weight of dry soil during casting, with plain OPC stabilized blocks acting as control. All blocks were cast to one target density and water content followed by moist curing for a period of 28 days. They were then subjected to compressive strength, water absorption, and efflorescence tests in accordance with Bureau of Indian standards (BIS) specifications. The results of the tests indicated that OPC stabilization resulted in blocks that met the specifications of BIS. Addition of SBA increased the compressive strength of the blocks and slightly increased the water absorption but still met the standard requirement of BIS code. It is concluded that addition of SBA to OPC in stabilized block manufacture was capable of producing stabilized blocks at reduced OPC content that met the minimum required standards.


2019 ◽  
Vol 1 (2) ◽  
pp. 140-146
Author(s):  
Nova Susanti

Strength Activity Index (SAI) is a method that aims to see the quality of additional materials mixed into the cement. The additional materials examined in this study were pozzolan from Lubuk Alung, pozzolan from Sicincin, and silica sand from Payakumbuh. This study refers to the ASTM C595/C595M-12 standard. The process started with placing specimens and mold (on a base plate) in a humid room or closet and protecting the surface from water droplets. After the mold was removed from the humid room or closet, the cubes were removed from the mold. The cubes were placed in suitable metal or glass containers, and the containers were sealed and stored at a temperature of 38.0±2.00C for 27 days. The specimens were cooled to 23.0±2.00C before the tests were carried out. The compressive strength results of pozzolan from Lubuk Alung, pozzolan from Sicincin, and silica sand from Payakumbuh were 327 kg⁄cm2, 296 kg⁄cm2 and 199 kg⁄cm2 respectively. Thus, the specimens which fulfilled the SAI requirement according to ASTM C-618 were pozzolan from Lubuk Alung and pozzolan from Sicincin with 91.34% and 82.68%, respectively. In contrast, silica sand from Payakumbuh did not fulfill the requirement of ASTM C-618 at a minimum of 75% because the result obtained was only 55.58%.


2014 ◽  
Vol 894 ◽  
pp. 342-348
Author(s):  
Abdoullah Namdar ◽  
Fadzil Mat Yahaya

The quality of a construction material satisfies stability of structure. Several additives have been innovated for improve quality of compressive strength of concrete. In this paper for enhancement of compressive strength of concrete, a simple method has been proposed. The kaolin and bentonite have been treated by heat for duration of 1 hour, with constant temperature. For kaolin 200 oC, 400 oC, 600 oC, 800 oC, 1000 oC and 1200 oC of heat, and for bentonite 200 oC, 400 oC, 600 oC, 800 oC of heat has been subjected. The kaolin and bentonite treated by heat have been proposed as additive for concrete. The objective is to introduce an additive to improve compressive strength of concrete. The microstructure of modified Ordinary Portland Cement (OPC) paste has been investigated by using Field Emission Scanning Electron Microscopy (FESEM) and X-ray diffractometry (XRD). The results indicate that the best level of heat for produce additives from kaolin and bentonite, and illustrate quantity of additives for replace a portion of cement in concrete application. Modification of nanoparticles of cement paste during hydration has been discussed.


2013 ◽  
Vol 662 ◽  
pp. 433-436
Author(s):  
Jiang Zhu ◽  
Guo Zhong Li

Vitrified micro bubbles thermal insulation material was made of vitrified micro bubbles, cement, fly ash, gypsum and sodium silicate, by molding process. VAE emulsion and stearic acid-polyvinyl alcohol emulsion were added to improve water resistance of the material. Mixed with 10% VAE emulsion and 5% stearic acid-polyvinyl alcohol emulsion, properties of the material are followed as: flexural strength 0.64MPa, compressive strength 1.35MPa, softening coefficient 0.71 and 2h volumetric water absorption 6.9%.


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