Swelling Potential Indexes of Swelling Rock in Zhangjiakou District

2010 ◽  
Vol 163-167 ◽  
pp. 2791-2797
Author(s):  
Dong Wang ◽  
Guo Xiang Yang ◽  
Fa Quan Wu ◽  
Jin Yu Dong
Keyword(s):  
Water Absorption ◽  
Linear Correlation ◽  
Specific Area ◽  
Liquid Limit ◽  
Comprehensive Analysis ◽  
Swelling Potential ◽  
Water Absorption Coefficient ◽  
Saturated Water ◽  
Mineral Components ◽  
Swelling Rock

The indexes to determine the swelling potential of swelling rocks are still not unified. A series of testing results of swelling rocks of Zhangjiakou showed that: the dry saturated water absorption and the specific area of swelling rock are all correlated linearly with the content of smectite and the correlation coefficient can be reached to 87% and 96% respectively; however, content of the montmorillonite and free expansive ratio is in nonlinear correlation, which indicated that the free expansive ratio, the dry saturated water absorption and specific area can all reflect the characters of mineral components in swelling rocks. However, the liquid limit and the plasticity index were all in linear correlation with the montmorillonite content, but value of them were lower than practical ones, so they can not be suitable indexes to determine the expansibility of swelling rocks. The larger the free swelling ratio was, the larger the expensive ratio under no load was, but they have no good correlations which indicated that the properties of swelling rocks was complex, as a result it is defective tightness to determine the swelling potential only by mineral components. The swelling force and the expansive ratio under no load were also in linear correlation, which meant they can all characterize the swelling characters of swelling rocks. The lager the dry saturated water absorption was, the poorer the durability was, but the dry saturated water absorption can not reflect the disintegrative totally. Through comprehensive analysis, we took the dry saturated water absorption, coefficient of disintegrative and swelling force as the indexes to determine the swelling potential of swelling rocks.

Research on the Criterion and Classification of Swelling Rock

2011 ◽  
Vol 261-263 ◽  
pp. 1836-1840
Author(s):  
Xun Guo Zhu
Keyword(s):  
Water Absorption ◽  
Soft Rock ◽  
Saturated Water ◽  
Swelling Rock

Criterion and classification are two important content of swelling soft rock research. On the basis of the study of predecessors’ achievements, the percentage of hydrophilic minerals is considered as a key index of the new standard, and the saturated water absorption, limit swelling increment, limit swelling force are considered as main indexes. Finally, the new standard is used to analyze and study on the projects in references.

Preparation of Pottery from Shale

2007 ◽  
Vol 336-338 ◽  
pp. 2062-2064
Author(s):  
Xiu Ling Tang ◽  
Min Fang Han ◽  
Qi Wang
Keyword(s):  
Compressive Strength ◽  
Water Absorption ◽  
Apparent Density ◽  
Expansion Ratio ◽  
Mineral Components ◽  
Deposit Density

The main chemistry ingredients of the shale in Baoding, China, are SiO2 and Al2O3, and the mineral components are quartz, feldspar and mica. The shale was sintered to produce pottery at 1000 ~ 1300°C and its deposit density and expansion ratio were measured. The compressive strength, apparent density, water absorption, etc, of some sintered samples with expansion ratio more than 1.5 were measured according to GB/T17431.2-1998. When sintered at 1150°C for 15 min, the expansion ratio of the shale is 1.96. When sintered at 1200°C for 10 min, the expansion ratio is 2.00. The performances of the prepared pottery accord with GB/T17431.2-1998: the compressive strength is 3.8MPa with the expansion ratio 1.96, the compressive strength is 4.2MPa with the expansion ratio 2.00. The water absorption is 4.9~5.8%, according with GB/T17431.2-1998.

scholarly journals Water Absorption Properties of Geopolymer Foam after Being Impregnated with Hydrophobic Agents

Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4162
Author(s):  
Hiep Le Chi ◽  
Pavlína Hájková ◽  
Su Le Van ◽  
Petr Louda ◽  
Lukáš Voleský
Keyword(s):  
Compressive Strength ◽  
Water Absorption ◽  
Positive Impact ◽  
High Sensitivity ◽  
Acoustic Properties ◽  
Total Water ◽  
Absorption Properties ◽  
Major Barrier ◽  
Water Absorption Coefficient ◽  
Hydrophobic Agent

Geopolymer foam is classified as a lightweight material with high porous in its matrix which has great offer for applications requiring fire-resistant, thermal, and acoustic properties. However, the high sensitivity to humid environments can be a major barrier of geopolymer foam that limits the variety of applications of this material. Based on this drawback, two types of hydrophobic agent (Lukosil M130 and Lukofob ELX) were used as an impregnator to treat the surface of geopolymer foam samples. This paper presented the results of water absorption properties of the untreated and treated geopolymer foam composites. The obtained properties were flexural strength, compressive strength, density, total water absorption, the rate of water absorption, and water absorption coefficient. The results showed that the samples after being impregnated with hydrophobic agents improved significantly their waterproof property especially using Lukosil M130. Moreover, the samples treated with Lukosil M130 had positive impact on their mechanical strength.

scholarly journals Exposing Sustainable Mortars with Nanosilica, Zinc Stearate, and Ethyl Silicate Coating to Sulfuric Acid Attack

2018 ◽  
Vol 10 (10) ◽  
pp. 3769 ◽  
Author(s):  
Victoria García-Vera ◽  
Antonio Tenza-Abril ◽  
Marcos Lanzón ◽  
José Saval
Keyword(s):  
Compressive Strength ◽  
Sulfuric Acid ◽  
Mass Loss ◽  
Water Absorption ◽  
Zinc Stearate ◽  
Acid Exposure ◽  
Ethyl Silicate ◽  
Acid Attack ◽  
Water Absorption Coefficient ◽  
Silicate Coating

Obtaining durable materials that lengthen the service life of constructions and thereby contribute to sustainability requires research into products that improve the durability of cementitious materials under aggressive conditions. This paper studies the effects of sulfuric acid exposure on four mortar types (control mortar, mortar with nanosilica, mortar with zinc stearate, and mortar with an ethyl silicate coating), and evaluates which of them have better performance against the acid attack. After 28 days of curing, the samples were exposed to a sulfuric acid attack by immersing them in a 3% w/w of H2SO4 solution. Physical changes (mass loss, ultrasonic pulse velocity, open porosity, and water absorption), and mechanical changes (compressive strength) were determined after the sulfuric acid exposure. A scanning electron microscope (SEM) was used to characterize the morphology of the surface mortars after the exposure. The control mortar had the highest compressive strength after the acid attack, although of the four types, the zinc stearate mortar showed the lowest percentage of strength loss. The zinc stearate mortar had the lowest mass loss after the acid exposure; moreover, it had the lowest capillary water absorption coefficient (demonstrating its hydrophobic effect) both in a non-aggressive environment and acid attack.

Development of Nano Modified Eco-Friendly Green Binders for Sustainable Construction Applications

2019 ◽  
Vol 24 ◽  
pp. 25-36 ◽  
Author(s):  
Hamada Shoukry
Keyword(s):  
Water Absorption ◽  
Mechanical Performance ◽  
Raw Material ◽  
Sustainable Construction ◽  
Partial Replacement ◽  
Cementitious Composites ◽  
Water Absorption Coefficient ◽  
Compressive And Flexural Strengths ◽  
Cement Manufacturing

Cement manufacturing, which is partially responsible for environmental and health risks as well as the greenhouse gas emissions, is a binder industry that needs energy and raw material. To decrease the needing, this study develops nano-modified eco-friendly cementitious composites including industrial solid wastes and/or by-products. For this purpose, ordinary Portland cement (OPC) was partially replaced with 70 wt% of fly ash (FA), Nano metakaolin (NMK) was incorporated at a rate of 2, 4, 6, 8, 10, 12 and 14 % as partial replacement by weight of FA to take advantage of the great role of nano materials in improving the mechanical and physical properties of cement based materials. Compressive strength, flexural strength, and capillary water absorption coefficient have been studied at 28 days of curing according to the international ASTM standards. Differential scanning calorimeter (DSC) was used to study the phase composition/decomposition. The microstructure characteristics of the hardened samples were investigated by scanning electron microscope (SEM) equipped with energy dispersive analytical x-ray unit (EDAX). The results revealed that the partial replacement of cement by 70% of FA has reduced both compressive and flexural strengths by about 45% in addition; the water absorption has been increased by about 175% as compared to the OPC. The replacement of FA by different amounts of NMK compensate for the loss in strength by about 75%. Furthermore, NMK has considerably improved the microstructure and reduced the water absorption by 86%. The study concluded that, it is possible to substitute 70% of the weight of the cement in the production of eco-friendly cementitious composites with improved mechanical performance attaining 88% of the corresponding performance of the hydrated OPC. The developed composites can be considered as green binders and recommended for various applications in construction industry.

Ermittlung der Kapillartransportkoeffizienten mineralischer Baustoffe aus dem w-Wert / Estimating the capillary transport coefficients of mineral building materials from the water absorption coefficient

1997 ◽  
Vol 3 (3) ◽  
pp. 219-234
Author(s):  
M. Krus ◽  
A. Holm ◽  
Th. Schmidt
Keyword(s):  
Absorption Coefficient ◽  
Water Absorption ◽  
Building Materials ◽  
Transport Coefficients ◽  
Capillary Transport ◽  
Water Absorption Coefficient ◽  
Standard Material ◽  
Moisture Balance ◽  
Computer Calculations ◽  
Building Components

Abstract Computer calculations are of increasing importance for the assessment of moisture balance in building components, since modern calculation methods achieve good agreement with measurements. A broader application of these methods is hampered, however, by the laborious measurements needed to determine the capillary transport coefficients essential for the calculations. A new method is therefore presented which allows to estimate the coefficients from wellknown standard material properties (free capillary saturation, practical moisture content and water absorption coefficient). These coefficients are sufficient for estimative assessment of the moisture balance of many materials, as is demonstrated by comparison of suction profiles calculated in this way and measured profiles.

scholarly journals The influence of type of cement on the degradation of microstructure and transport properties of cement mortars exposed to frost induced damage

2018 ◽  
Vol 174 ◽  
pp. 01014
Author(s):  
Alicja Wieczorek ◽  
Marcin Koniorczyk
Keyword(s):  
Absorption Coefficient ◽  
Pore Structure ◽  
Water Absorption ◽  
Transport Properties ◽  
Cement Mortar ◽  
Gas Permeability ◽  
Water Absorption Coefficient ◽  
Freeze Thaw ◽  
Cement Mortars ◽  
Small Pore

The purpose of the study is to understand how the cyclic water freezing (0, 25, 50, 75, 100 and 150 freeze-thaw cycles) impacts microstructure and transport properties of cement-based materials. Tests were conducted on cement mortars with different water/cement ratios (w/c=0.45 and 0.40) and on two types of cement (CEM I and CEM III) without air-entraining admixtures. The changes of pore size distribution and open porosity were investigated by means of mercury intrusion porosimetry. Additionally, the relationship between intrinsic permeability and the water absorption coefficient of cement mortar samples was analysed. The water absorption coefficient and gas permeability were determined using capillary absorption test and the modified RILEMCembureau method. The evolution of transport coefficients with growing number of freeze-thaw cycles were determined on the same sample. It was also established that change of pore structure (a decrease of small pore volume <100nm and increase of larger pores >100nm) induces an increase of water transport parameters such as permeability and water absorption coefficient. The higher gas permeability corresponds to the higher internal damage. In particular, it is associated with the change of cement mortar microstructure, which indicates damage of narrow channels in the pore structure of cement mortars.

Sign in / Sign up

Export Citation Format

Share Document