scholarly journals CONSTRUCTION QUALITY CONTROL OF UNBOUND LAYERS BASED ON STIFFNESS MODULUS CRITERIA / NESUJUNGTŲ SLUOKSNIŲ KONSTRUKCIJŲ KOKYBĖS KONTROLĖ, ĮVERTINANT STANDUMO MODULIO KRITERIJŲ

2012 ◽  
Vol 18 (1) ◽  
pp. 5-13 ◽  
Author(s):  
Kamran Rafiei ◽  
Amir Kavussi ◽  
Shahaboddin Yasrobi
Keyword(s):  
Quality Control ◽  
Moisture Content ◽  
Laboratory Testing ◽  
Field Testing ◽  
Engineering Properties ◽  
Construction Sites ◽  
Construction Quality ◽  
Stiffness Modulus ◽  
In Situ Conditions ◽  
Moisture Percentage

NDT methods such as Portable Falling Weight Deflectometer (PFWD) provide measurements based on the engineering properties of materials (stiffness) instead of physical properties like field density and moisture content. However, PFWD testing method is not yet proven to be reliable enough for construction quality control. In this research, a laboratory testing unit box was prepared in which unbound materials were compacted at different compaction levels. The stiffness modulus of the compacted layers were then determined under PFWD Testing. The tests were repeated several days after construction when the materials moisture content was decreased to lower values. The results indicated that acceptable correlations exist between the stiffness modulus and both compaction percentage and moisture percentage. In addition, field testing was carried out on different unbound layers in several highway construction sites in Tehran and laboratory results were used in order to control in-situ conditions. With Comparing field and laboratory testing results, it was concluded that PFWD is an appropriate testing device for quality control and compaction monitoring of pavement layers during construction phases. Santrauka NDT metodai, kaip krintančio svorio deflektometrai (PFWD), leidžia matuoti technologines ir fizikines medzcaron;iagu savybes (standumą, tankį ir įmirki). Tačiau PFWD bandymu metodas ir dabar dar nera patvirtintas kaip patikimas konstrukcijų kokybei kontroliuoti. Šiame darbe atlikti laboratoriniai ir natūriniai bandymai, kuriuose buvo tirtos skirtingais lygiais sutankintų tarpusavyje nesujungtų sluoksnių konstrukcijos. Tiriamų medžiagų sluoksnių standumo moduliai buvo nustatyti PFWD metodu. Bandymas buvo pakartotas išlaikius konstrukciją keletą dienų, kai drėgmės kiekis medžiagose sumažejo. Rezultatai parodė, kad yra reikšmine koreliacija tarp standumo modulio ir abiejų sluoksnių sutankinimo lygio bei drėgmės kiekio. Vėliau Teherano vietovese buvo atlikti natūriniai konstrukcijų su skirtingais nesujungtais sluoksniais bandymai. Išanalizavus natūriniu ir laboratoriniu bandymų tyrimų rezultatus, buvo nustatyta, kad PFWD yra tinkamas bandymo metodas konstrukcijų kokybei kontroliuoti ir tinkamam dangos sluoksnių tankinimui parinkti.

Construction Control As A Strategy For Improving The Quality Of Buildings And Structures

2020 ◽  
Keyword(s):  
Quality Control ◽  
Life Cycle ◽  
Construction Control ◽  
Construction Sites ◽  
Actual Problem ◽  
Construction Market ◽  
Construction Products ◽  
Underlying Causes ◽  
Required Quality

In construction production, the safety of constructing buildings and structures is achieved by ensuring the required quality as a result of systematic construction control based on the implementation of a complex of technical, economic and organizational measures at all stages of the object's life cycle. The article deals with the actual problem of improving the quality of construction products-buildings and structures in conjunction with the activities of construction control bodies. The article presents the advanced foreign and domestic experience of ensuring the quality control at the construction sites, providing for the prevention of the underlying causes of defects and increasing the interest of the contractors directly. On the basis of the analysis of the current situation with quality control at the construction market, ways to improve its efficiency by developing a unified system of technological implementation of relevant requirements for the quality of construction products, determining the rational number and business load of construction control engineers, as well as the active activities of self-regulatory organizations in this area are offered.

scholarly journals Development of a rapid field testing method for metals in horizontal directional drilling residuals with XRF sensor

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hailin Zhang ◽  
João Antonangelo ◽  
Chad Penn
Keyword(s):  
Moisture Content ◽  
Standard Method ◽  
Field Testing ◽  
Field Method ◽  
Filter Press ◽  
Directional Drilling ◽  
Horizontal Directional Drilling ◽  
Excess Water ◽  
Spiked Soil

AbstractPortable X-ray fluorescence (pXRF) spectrometer allows fast in-situ elemental determination without wet digestion for soils or geological materials, but the use of XRF on wet materials is not well documented. Our objective was to develop a rapid field method using pXRF to measure metals in the residues from horizontal directional drilling (HDD) operations so that proper disposal decisions can be made in-situ. To establish the procedure, we spiked soil samples with 4 concentrations of Cr, Ni, Cu, Zn, As, Cd, and Pb up to 1000 mg kg−1, and then the metal concentrations were determined by wet chemical method after drying and acid digestion (standard method), and by pXRF, also at laboratory conditions, after drying and at two different moisture conditions. The measurements by pXRF and standard method after drying and after removal of excess water (AREW) were highly correlated with slopes ranging from 0.83 ± 0.01 to 1.08 ± 0.01 (P < 0.001) for all metals. The relationship was better AREW than the saturated paste without removal of excess water and the moisture content affected only the accuracy of As, Cd, and Pb. The procedure established was successfully used for HDD residues collected from 26 states of US with moisture content ranging from 14 to 83% AREW. The pXRF was proven to be a reliable tool for fast detection of common metals in dried soils and HDD residues, and samples containing < 30% moisture content without needing to correct for moisture. If the moisture is > 30%, excess water in samples need to be removed with a commercially available filter press to achieve high accuracy. The developed procedures reduce time of metal detection from days to about an hour which allows drilling operators to make quick decisions on soil or HDD disposal.

scholarly journals Moisture Measurement in Paper and Cardboard Packaging Waste Bales for Recycling

2021 ◽  
Vol 11 (10) ◽  
pp. 4586
Author(s):  
Ana Silveira ◽  
João Cardoso ◽  
Maria José Correia ◽  
Graça Martinho
Keyword(s):  
Quality Control ◽  
Dielectric Properties ◽  
Moisture Content ◽  
Reliable Method ◽  
Drying Method ◽  
Waste Streams ◽  
Oven Drying ◽  
Quality Issue ◽  
Commercial Device ◽  
Non Destructive

Moisture content is a quality issue raised by recycling plants in the acceptance of paper and cardboard coming from waste streams. The current way to measure this parameter is by the oven drying method, which is a slow and invasive process, costing time and resources for the recyclers to do this type of quality control. An alternative to such a measurement technique is the use of plate-form devices which indirectly measure the moisture content using the dielectric properties of water and paper. This study has tested this method and developed a representative equation for the use of devices with these properties in the Portuguese market. For that, 48 wastepaper and cardboard bales were tested with both the traditional (oven drying) method and a commercial device equipped with dielectric technology. An equation that fits the studied reality (R2 = 0.76) was achieved, and possible problems regarding the use of this device were tested. The results showed that this type of device could be used as a time- and cost-saving, non-destructive and reliable method in the quality control of wastepaper and cardboard bales.

Achieving Quality Reproducible Results and Maintaining Compliance in Molecular Diagnostic Testing of Human Papillomavirus

2003 ◽  
Vol 127 (8) ◽  
pp. 978-983 ◽  
Author(s):  
Jacqueline M. Seabrook ◽  
Roger A. Hubbard
Keyword(s):  
Quality Control ◽  
Human Papillomavirus ◽  
Method Validation ◽  
Proficiency Testing ◽  
Laboratory Testing ◽  
Clinical Laboratory ◽  
Laboratory Accreditation ◽  
Medical Laboratory ◽  
Molecular Diagnostic ◽  
High Complexity

Abstract Laboratories contemplating either the addition of new molecular tests or modifying methods approved by the Food and Drug Administration for human papillomavirus testing should be aware of a variety of procedural, performance, and regulatory issues surrounding such activity. Diagnostic medical laboratory testing in the United States is regulated by the Centers for Medicare and Medicaid Services, an agency formerly known as the Health Care Finance Administration. The regulatory vehicle of the Centers for Medicare and Medicaid Services is manifested in the Clinical Laboratory Improvement Amendments (CLIA). The CLIA program has put into place specific regulations for laboratory quality control, which includes specific recommendations for method validation. Regulations that must be followed regarding personnel, quality control, quality assurance, method validation, and proficiency testing depend on the complexity category of the individual test. All molecular diagnostic tests, including those for human papillomavirus, are considered high complexity. The Centers for Medicare and Medicaid Services retains the authority to allow private, national accreditation organizations to “deem” that a laboratory is compliant with CLIA '88 requirements. Accreditation organizations, such as the Joint Commission for Accreditation of Hospitals, the Commission on Office Laboratory Accreditation, and the College of American Pathologists (CAP), as well as several state medical laboratory–accrediting agencies, possess the authority to deem laboratories as “CLIA-approved.” The CAP, through its Laboratory Accreditation Program, has promoted standards for laboratory performance and method validation. In general, guidelines set forth in the CAP Laboratory Accreditation Program checklists specify that all clinical laboratory testing must essentially meet those requirements defined for high-complexity testing under CLIA '88, including test validation standards, reportable/reference ranges, performance criteria, and proficiency testing.

EFFECT OF WET TROPICAL WEATHERING ON THE STRENGTH OF SANDSTONE

2015 ◽  
Vol 76 (2) ◽  
Author(s):  
Edy Tonnizam Mohamad ◽  
Maybelle Liang ◽  
Nurmunirah Mohd Akhair
Keyword(s):  
Moisture Content ◽  
Moisture Absorption ◽  
Initial Moisture Content ◽  
Point Load ◽  
Engineering Properties ◽  
Strength Index ◽  
Tropical Weathering ◽  
Load Tests ◽  
Grade Ii ◽  
Weathering Grades

 The influence of moisture content to the strength of wet tropically weathered sandstone of Jurong Formation found in Nusajaya, Johor was studied. The rock materials have been affected by weathering action; hence the alteration of its engineering properties is incontestable due to these effects. A total of 36 samples representing various weathering grades were collected from the field and tested at various moisture content by immersing them in water at different duration of time, ranging from 15, 30 and 60 minutes. Point load tests for the determination of the strength index Is(50) of the rock were then carried out. For weathered sandstone (Grade II to IV), the mean initial moisture content ranges from 0.15% to 11.00% respectively, while the initial mean strength index has maximum and minimum values of 7.76 MPa and 0.38 MPa. The results reveal that there is a significant relationship between the weathering grades, moisture absorption and strength. The moisture absorption is dependent on the amount of clay minerals present in the rock material, which indirectly affects the strength, as observed with the increment of weathering state. In conclusion, this study indicates that sandstone with higher moisture content and increase in weathering grade exhibits lower strength values. 

A soil moisture meter. Depending on the “capillary pull” of the soil. With illustrations of its use in fallow land, grass orchard, and irrigated orchards

1935 ◽  
Vol 25 (3) ◽  
pp. 326-343 ◽  
Author(s):  
W. S. Rogers
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Soil Moisture Content ◽  
Continuous Measurement ◽  
Fallow Land ◽  
Soil Particles ◽  
Moisture Meter ◽  
Two Factors ◽  
Moisture Percentage ◽  
Mercury Manometer

1. A soil moisture meter which gives direct and continuous measurement of the soil moisture content is described. The instrument consists of a special porous pot filled with water, connected by a tube to a mercury manometer. The pot is buried in the soil, whose capillary pull causes the mercury to rise. The height to which the mercury rises depends on the amount of moisture in the soil, and also on the size of soil particles and the degree of compactness of the soil. (The last two factors remain constant for an instrument in one position.)2. To read actual moisture percentage each instrument has to be calibrated for the soil in which it is placed. Once this is done, all sampling and weighing is eliminated.

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