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From page 12... ... 12 Construction Quality Management Using Intelligent Compaction Introduction Technological improvement of construction technologies has resulted in the popularity of the IC techniques. Even though the basic concept of IC was developed in the early 1970s (Adam and Pistrol 2016) Read the entire page →
From page 13... ... Construction Quality Management Using Intelligent Compaction 13 State of Stress. Several material models have evolved in the decades since the 1960s. Read the entire page →
From page 14... ... 14 Evaluating Mechanical Properties of Earth Material During Intelligent Compaction b = maximum of log (MR/MRopt) , β = regression parameter = ln (–b/a) Read the entire page →
From page 15... ... Construction Quality Management Using Intelligent Compaction 15 Numerical Modeling Techniques of Roller Compaction Experimental data collected with instrumented roller compactors has revealed complex nonlinear roller vibration behaviors, which include the loss of contact between the drum and the soil, as well as the drum and the frame rocking (Adam and Kopf 2004; Anderegg and Kaufmann 2004; Mooney et al. Read the entire page →
From page 16... ... 16 Evaluating Mechanical Properties of Earth Material During Intelligent Compaction impede the implementation of the modulus-based quality acceptance was the incorporation of the resilient modulus tests in the specifications. If nonlinear models are to be adopted, an indirect means of estimating the nonlinear model parameters should be considered. Read the entire page →
From page 17... ... Construction Quality Management Using Intelligent Compaction 17 ACE (Ammann Compaction Expert) that calculated the soil stiffness parameter ks (also called kB) Read the entire page →
From page 18... ... 18 Evaluating Mechanical Properties of Earth Material During Intelligent Compaction system determines the drum inertia and the eccentric force by measuring the vertical drum acceleration and eccentric mass position, whereas the frame inertia is neglected. The vertical drum displacement amplitude, zd, is determined by the spectral decomposition and integration of the measured peak drum accelerations (Anderegg and Kaufmann 2004) Read the entire page →
From page 19... ... Construction Quality Management Using Intelligent Compaction 19 Current Backcalculation Techniques Backcalculation (also called system identification or inversion) is an optimization process performed to inverse map a known relation established by discrete or continuous data points. Read the entire page →
From page 20... ... 20 Evaluating Mechanical Properties of Earth Material During Intelligent Compaction In the inverse process, the calculated responses are compared to the measured responses so that the new mechanical properties are determined by a parameter identification routine. Optimization is achieved through an iterative process until the differences between the calculated and measured deflections stay under a certain error criterion. Read the entire page →
From page 21... ... Construction Quality Management Using Intelligent Compaction 21 either mean ICMV (Option 2a) or spatial percentage change in ICMV (Option 2b) Read the entire page →
From page 22... ... 22 Evaluating Mechanical Properties of Earth Material During Intelligent Compaction Reference FHWA Soils AASHTO GPS verbiage HPPS 1 RTK-GPS GPS verification tolerance 12 inch 6 inch Temperature verification tolerance (for asphalt) NO 5°F Require alignment files NO YES 2 Departmental approval of rollers NO YES Roller vendors listed NO NO Test strip required YES YES Pre-construction mapping YES 3 NO Veta software required YES YES IC training 4-8 hours 4 Required 5 IC training includes Veta YES NO 6 Data submittal Daily Daily IC-based acceptance NO 7 NO Basis of payment Lump sum Lump sum and partial 8 1HPPS is intended to include all positioning technologies including GPS, laser, cellular signals, and so forth. Read the entire page →
From page 23... ... Construction Quality Management Using Intelligent Compaction 23 The "Special Note for Intelligent Compaction of Aggregate Bases and Soils" of the Kentucky Transportation Cabinet (KYTC) follows the FHWA guidelines and specifies the use of RTK-GPS. Read the entire page →
From page 24... ... 24 Evaluating Mechanical Properties of Earth Material During Intelligent Compaction Pre-Approval of IC System Requirements and Quality Control Rollers Types, Vendors and Department Approval. Agency specifications typically require that contractors submit documentation of the roller supplier, make, and roller model, along with the number of IC rollers to be provided for the project. Read the entire page →
From page 25... ... Construction Quality Management Using Intelligent Compaction 25 Conventional Spot Testing. IC technology is currently used for quality control, but the acceptance is still based on the geomaterial density and sometimes on moisture measurements made with the NDG. Read the entire page →
From page 26... ... 26 Evaluating Mechanical Properties of Earth Material During Intelligent Compaction the appendices regarding contractor personnel and provides a checklist to approve IC rollers. Like the pavement profiler certification, this certification is not trivial, and it may be costly to establish and operate. Read the entire page →

From page 12...

... 12 Construction Quality Management Using Intelligent Compaction Introduction Technological improvement of construction technologies has resulted in the popularity of the IC techniques. Even though the basic concept of IC was developed in the early 1970s (Adam and Pistrol 2016)