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From page 89... ... 90 chapter five STIFFNESS-BASED SPECIFICATIONS FOR COMPACTION CONTROL OF UNBOUND MATERIALS INTRODUCTION Although current common quality control specifications that use dry density and/or moisture content criteria are relatively straightforward and practical, they do not reflect the engineering properties of unbound materials necessary to ensure a high-quality product. In addition, the design of pavements and embankments is based on stiffness and/or strength parameters. Read the entire page →
From page 90... ... 91 Maximum Allowable DPI mm blow 4.76 GN 1.68MC – 14.4 (64) Read the entire page →
From page 91... ... 92 have small GN values. Such materials have larger strength and modulus values than do those with large amounts of fine sand. Read the entire page →
From page 92... ... 93 any width throughout the first 3,058.2 m3 (4,000 yd3) Read the entire page →
From page 93... ... 94 LWD data. They also ensure that the LWD influence depth extends to the bottom of a common lift thickness. Read the entire page →
From page 94... ... 95 compaction control of granular materials and is currently used in about 50% of projects involving such materials. The LWD has been used to a much lesser extent by some districts mainly for granular materials but also for projects involving nongranular materials. Read the entire page →
From page 95... ... 96 ∼ wcoptNDCP req 0 12 in. Read the entire page →
From page 96... ... 97 of 300 mm (11.8 in.) , an accelerometer attached to the center of the loading plate for measuring the maximum vertical deflection, and falling mass of 10 kg (22 lb) Read the entire page →
From page 97... ... 98 The QM-E specification includes five key evaluation criteria for compaction control of soil embankment layers: moisture content, density, lift thickness, stability, and uniformity. The tests to assess the moisture content, density, and lift thickness are required for every 500 m3 of fill. Read the entire page →
From page 98... ... 99 where TrE = site relative compaction at a given water content; and Trw = the moisture correction coefficient to adjust for differences between the measured moisture content and optimum moisture content. This is determined based on the results of a modified Proctor test conducted on samples of the material used in the field using the following equation: (71) Read the entire page →
From page 99... ... 100 correction factor based on Table 32. The correction factor needs to be added to the LWD moduli measured in the field to achieve an equivalent LWD modulus at the optimum moisture content. Read the entire page →
From page 100... ... 101 consists of selecting the most suitable material to ensure a durable layer. In the third step, the selected material for each layer should be tested in the laboratory at the field compaction and moisture conditions to obtain a representative design modulus. Read the entire page →
From page 101... ... 102 Minnesota IC Specification A pilot specification was implemented by the Minnesota DOT in 2006 during the construction of TH 64 in Akeley, Minnesota, and was later updated in 2010 and 2012. In this specification, all segments of projects in which IC rollers are used should be compacted so that at least 90% of the IC measurements are equal to or exceed 90% of the target ICMV before the next lift is placed. Read the entire page →
From page 102... ... 103 Agency Equipment Field Size Location Specs Documentation Compaction Specs Speed Frequency FHWA (2012) Vibratory selfpropelled singledrum roller 225 ft (75 m) Read the entire page →
From page 103... ... 104 TABLE 34 SUMMARY OF INTERNATIONAL IC SPECIFICATIONS Agency Equipment Field Size Location Specs Documentation Compaction Specs Speed Frequency ISSMGE Roller chosen by experience 100 m by the width of the site Homogenous, even surface. Track overlap 10% drum width. Read the entire page →
From page 104... ... 105 Minnesota, and Texas) , also has developed IC specifications. Read the entire page →

From page 89...

... 90 chapter five STIFFNESS-BASED SPECIFICATIONS FOR COMPACTION CONTROL OF UNBOUND MATERIALS INTRODUCTION Although current common quality control specifications that use dry density and/or moisture content criteria are relatively straightforward and practical, they do not reflect the engineering properties of unbound materials necessary to ensure a high-quality product. In addition, the design of pavements and embankments is based on stiffness and/or strength parameters.