Model for Moisture-Content Evolution in Porous Building Elements with Hygro-Thermal Bridges and Air-Voids

2000 ◽  
Vol 24 (1) ◽  
pp. 10-41 ◽  
Author(s):  
REGINA KATSMAN ◽  
RACHEL BECKER
Keyword(s):  
Moisture Content ◽  
Air Voids ◽  
Thermal Bridges ◽  
Building Elements

Prediction of Asphalt Cement Content of Compacted Hot-Mix Asphalt Specimens Using Nuclear Gauges

1996 ◽  
Vol 1545 (1) ◽  
pp. 169-177
Author(s):  
Iyad A. Alattar ◽  
Imad L. Al-Qadi
Keyword(s):  
Moisture Content ◽  
Hot Mix Asphalt ◽  
Extraction Methods ◽  
Void Content ◽  
Study Program ◽  
Aggregate Gradation ◽  
Air Voids ◽  
Asphalt Cement ◽  
Specimen Weight ◽  
A New Technique

Determining asphalt cement (AC) content of hot-mix asphalt (HMA) for quality control/quality assurance using extraction methods is a lengthy, time-consuming, and hazardous process. A demand for a faster and safer method led to the development of different nuclear gauges capable of predicting the AC content of HMA samples. Measuring the AC content of compacted specimens by nuclear gauges is a new technique whose feasibility was evaluated. A total of 216 Marshall compacted specimens were cast and tested in an attempt to develop correction models. The study program investigated the effect of various HMA parameters on the measured AC content, including aggregate gradation and type, air void content, moisture content, AC content, and specimen weight. Specimens were prepared at two different mix design formulas using AC-30 and compacted at two different compaction efforts to investigate the effect of air voids. Specimens (1200 g each) used for calibration were prepared at 3 to 7 percent AC content, whereas specimens prepared for measurements were prepared at 4 to 6 percent. Quartzite and diabase aggregate were used as open and dense graded in prepared mixes. Three levels of moisture content in HMA were evaluated. Different calibration models were developed for different asphaltic mixtures. The evaluated nuclear gauge for measuring AC content for compacted HMA specimens produced satisfactory results when the parameters of tested and calibration parameters were the same. The study found that specimen weight is the most significant factor. Other parameters have different degrees of influence on the measured AC content. Statistical models were developed to correct for the evaluated parameters.

Preliminary remarks on porosity of soil aggregates in air-dry state and at pF 2.

1961 ◽  
Vol 9 (3) ◽  
pp. 168-173 ◽  
Author(s):  
H. Kuipers
Keyword(s):  
Organic Matter ◽  
Moisture Content ◽  
Water Content ◽  
Pore Volume ◽  
Pore Space ◽  
Soil Aggregates ◽  
Aggregate Size ◽  
Field Conditions ◽  
Swelling Properties ◽  
Air Voids

In pycnometer determinations of the pore volume of 2-5-mm air-dry aggregates from various soils of 1.5-2.5 and 2.6-3.5% organic-matter levels and various clay contents, the use of kerosene (S. & F. XVII [1897]) gave as good values as, and was more convenient than, the use of sand or mercury (the latter giving low porosities). The pore-space percentage of aggregates could be calculated from the water content at pF 2, when no air voids in the small aggregates are likely to occur and water between the aggregates is of no importance. Dry aggregates were only slightly denser in cores of light soils than under field conditions, and swelling was small; dry aggregates were very dense in heavy soils in which moisture content and density of aggregates appeared so closely related that it was difficult to distinguish between the effect of either on the strength of aggregates. Swelling properties and aggregate size are likely to be important factors in the structure of heavy soils. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Moisture Susceptibility of Warm Mix Asphalt (WMA) with an Organic Wax Additive Based on X-Ray Computed Tomography (CT) Technology

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Jie Ji ◽  
Hui Yao ◽  
Zhikai Yuan ◽  
Zhi Suo ◽  
Ying Xu ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Moisture Content ◽  
Void Content ◽  
Moisture Susceptibility ◽  
Air Voids ◽  
X Ray ◽  
X Ray Computed ◽  
Indirect Tensile ◽  
Air Void ◽  
Air Void Content

The warm mix asphalt was fabricated with different moisture contents (0%, 1%, 2%, and 3%) of limestone aggregates using the Superpave gyratory compactor. The moisture susceptibility of asphalt mixtures with an organic wax additive RH was studied. The samples were compacted and tested using the modified Lottman test AASHTO T283, and the X-ray computed tomography technology was used to capture the internal structure images before and after the freeze-thaw cycles. The test results show that the air voids were distributed in the size range of 0–5 mm3 and 5–10 mm3. The number of air voids decreased with the increase of air void size and increased after freeze-thaw cycles. The air void content can be influenced by the residual moisture in aggregates. The higher the moisture content of aggregates is, the larger the air void content is. So, the air void content is likely to be sensitive to moisture damage. The increase ratio of the air void and moisture content of aggregates had good correlation with the indirect tensile strength and tensile strength ratio of the samples. The indirect tensile strength and tensile strength ratio of the samples decreased linearly, and the samples were sensitive to the moisture damage with the increases of increase ratio of the air void/moisture content in aggregates.

Study of Nano-Kaolinite Properties in Clay Liner Application

2017 ◽  
Vol 889 ◽  
pp. 239-242
Author(s):  
Atiqah Najwa binti Zainuddin ◽  
Mazidah binti Mukri ◽  
Nik Nurul Syuhada binti Nik Ab Aziz ◽  
Mohamed Khatif Tawaf bin Mohamed Yusof
Keyword(s):  
Moisture Content ◽  
Optimum Moisture Content ◽  
The Other ◽  
Dry Density ◽  
Clay Liners ◽  
Maximum Dry Density ◽  
Air Voids ◽  
Clay Liner ◽  
Two Samples ◽  
Positive Effect

This paper reports the outcome of the laboratory investigation conducted on new clay liners modified with kaolinite combined with various content of lime-treated, various content of bentonite and admixture of kaolinite adding with 3% nano-kaolinite for composition. The 3% nano-kaolinite was chosen based on earlier finding by S.V.Netethu (2013). The various content of lime-treated and bentonite adopted are 2.0%, 5.0%, 7.5% and 10.0% by total weight of the kaolinite. Compaction tests was performed on the resulted modified clay liner samples to evaluate the best percentage that gives optimum moisture content (OMC) and maximum dry density (MDD) . The best percentage of each bentonite and lime-treated are chosen and be added into kaolinite and the physical properties of samples are tested and compared to the other two samples which are kaolinite only and kaolinite added with 3 % of nano-kaolinite. Nano-kaolinite was produced using a mill machine and the sized of nano-kaolinite (1nm-100nm) were examined under Scanning Electron Microscope (SEM) machine.The addition of 3% nano-kaolinite to the kaolinite gives the best compaction result compared to bentonite or lime-treated. The value of dry density is increased to give the reduction of air voids, thereby reducing the hydraulic conductivity by concept. Based on the compaction test value, it clearly observed that admixture of kaolinite adding with 3% nano-kaolinite gives the best results from the other samples due to required less water to achieve maximum dry density of 1.39 Mg/m3 and 27.34% of optimum moisture content resulted positive effect in soil properties.

Preparation and Standardization of a Stable AHF Plasma

1968 ◽  
Vol 19 (03/04) ◽  
pp. 423-429 ◽  
Author(s):  
G. M Thelin ◽  
Keyword(s):  
Moisture Content ◽  
Primary Standard ◽  
Healthy Male ◽  
Healthy Donors ◽  
Fresh Plasma

SummaryA stable, lyophilized AHF reference plasma has been prepared from pooled plasma from at least 50 normal healthy donors and standardized against a primary standard of fresh plasma from 20 healthy male donors aged 20 to 40. Average AHF potency of a typical lot is 98.8%, and moisture content is less than 0.5%. Under storage at -25° C, this AHF reference plasma is stable for at least 18 months. It has been used in several major coagulation laboratories, and has given consistently satisfactory and reproducible results in AHF assays.

Sign in / Sign up

Export Citation Format

Share Document