Intelligent Compaction of Soils—Data Interpretation and Role in QC/QA Specifications

This report describes a study of intelligent compaction (IC) technologies, within the context of actual construction projects, for its potential as a component of INDOT’s QC/QA for soils. The output from an IC-equipped roller compaction equipment is a real-time area mapping of the compacted lift stiffness as captured by the IC measure. Data was collected to evaluate the correlation between each of two IC measures—compaction meter value (CMV) and machine drive power (MDP)—and in situ embankment quality test measures, the chief in situ test being the dynamic cone penetrometer (DCP) test which INDOT uses for soil embankment acceptance testing. Researchers sought to understand how well the IC measures might assess embankment quality as currently evaluated by the in situ measures. Window-averaged IC measures were compared with the in situ DCP test points. For CMV, a variable correlation was found between the average CMV and DCP values from 74 in situ locations. Also, a limited head-to-head comparison of CMV and MDP with the in situ measures provided some indication that MDP should be studied further. Lessons were learned regarding the elimination of bias in future correlation studies, critical provisions to facilitate best data quality, and important aspects of data management. IC technology holds promise for monitoring the consistency of the soil compaction effort and flagging weak areas in real time during compaction operations. However, further insight is needed regarding the correlation of the DCP measure with both types of IC measures for various soil characterizations and field moisture conditions

A Synthesis Study on Collecting, Managing, and Sharing Road Construction Asset Data

Accurate and complete construction records and as-built data are the key prerequisites to the effective management of transportation infrastructure assets throughout their life cycle. The construction phase is the best time to collect such data. Assets such as underground drainage and culverts are visible and physically accessible only during construction. For assets such as guardrails, signals, and pavement, it is safer and more efficient to collect data during construction than after construction when the road segment is open to traffic. The purpose of this project was to conduct a synthesis study to 1) assess the current status at INDOT regarding the collection of asset data during the construction phase and the use of such data in the operation and maintenance (O&M) phase, and 2) develop a framework for INDOT to leverage the construction inspection and documentation process to collect data for assets. Data needs during O&M were identified through rounds of meetings with relevant INDOT business units. The current practice in construction documentation was investigated in detail. A survey of state highway agencies (SHAs) was conducted to assess the state-of-the-practice. A practical framework was developed to leverage the construction inspection and documentation practice to collect asset data that are needed in O&M. The framework uses specific pay items—construction activities that result in physical structures—as the bridge to connect plan assets (i.e. physical structures specified in the design documents) to their corresponding counterparts in the asset management systems. The framework is composed of 1) a data needs component for determining the information requirements from the O&M perspective, 2) a construction documentation module, and 3) a mapping mechanism to link data items to be collected during the construction documentation to data items in the asset management systems. The mapping mechanism was tested and validated using four priority asset classes—underdrains, guardrails, attenuators, and small culverts—from an INDOT construction project. The testing results show that the newly developed framework is viable and solid to collect asset data during the construction phase for O&M use in the future, without adding extra workload to construction crews. The framework can reduce/eliminate the duplicate data collection efforts at INDOT, leading to savings and efficiency gains in the long term

Mixed Reality Technology Applications in Construction Equipment Operator Training

Abstract: This paper provides information on Mixed Reality (MR), and more specifically Augmented Reality (AR) and their potential applications in heavy construction equipment and operator training. Mixed Reality involves the use of special display and tracking technologies that are capable of seamlessly merging digital (virtual) content into a real environment. Conceptual designs and application scenarios of two AR systems for construction are presented: an AR-based equipment management system (AR EMS) for maintenance, and repair of heavy equipment fleet, and an AR-based operator training system (AR OTS) that trains the novice operators in a real worksite environment populated with virtual materials and instructions

Mixed Reality Benefits for Design Perception

ABSTRACT: Design visualization is key to the communication and shared perception of designs and is essential for meaningful design development and collaborations. The initial development of an Augmented Reality Computer Aided Drawing (AR CAD) system for enhancing visualization of models created in standard CAD was presented at the 17th ISARC. AR CAD features a more natural mode for changing views of the model and completely understanding the model content. Expected benefits are improved efficiency in the design detailing function, both for the individual detailer and for design collaborations where maintaining an accurate shared understanding of the design model is critical. An experimental program is under way to examine the impact of AR CAD upon a user’s perception and recall of a design model. Related experiments with desktop and immersive virtual environments have found that motion cues can indeed markedly improve spatial cognition. It is expected that we will see the same benefits in our AR CAD system, although until now such studies have not been conducted in an AR environment. This paper presents the rationale for experiments to measure the impact of AR CAD in terms of cognition cost, and it lays the foundation for further application of Mixed Reality (MR) technology to the design, construction, and maintenance phases of a facility’s life cycle. MR applications may prove promising for effective communication of designs for prefabrication, site installation, and the planning and excecution of maintenance operations

Characterizing travel time distributions in earthmoving operations using GPS data

Recent advances in sensor technology have led to enhanced data acquisition capabilities in construction sites. A wealth of data are being collected from GPSequipped heavy vehicles for a wide range of monitoring, management, and analysis purposes. The availability of detailed GPS trajectory data has opened up new opportunities for modeling and simulation of real-world construction operations. One of the emerging areas in this regard is data-driven modeling and simulation, which is a modeling framework that attempts to automatically generate discrete-event simulation (DES) models based on a rich set of observed data as well as dynamically adapt the generated model to changes in data. Within the overall framework of automatically generating a DES simulation model for earthmoving operations, this paper focuses on developing methods to convert complex movement data collected from scrapers into a modeling element of activity-cycle diagram and activity scanning modeling paradigm-based DES system. Scraper changes travel routes at every cycle and its trip patterns (e.g., travel path and speed) are very difficult to generalize using a known parametric model (e.g., theoretical probability distribution), which in turn complicates the problem of automatic model generation. To deal with this issue, this paper proposes the use of relation between travel time and travel distance with regard to coefficient of variation measures, expressed in two separate distributions, to capture information needed to construct speed and path scenarios

Desmoglein-1 is a minor autoantigen in dogs with pemphigus foliaceus

The majority of human patients with pemphigus foliaceus (PF) have circulating IgG autoantibodies that target conformational epitopes on the desmosomal cadherin desmoglein-1 (dsg1). Limited studies using immunoblot techniques suggested that the principal autoantigen in dogs with PF might also be dsg1. It was the objective of this study to test this hypothesis. A comprehensive survey of canine PF sera was conducted using a novel screening strategy that detects conformational epitopes. This method consists of the ectopic expression of canine dsg1 at the surface of human 293T epithelial kidney cells and their live screening, i.e. prior to fixation. Out of seven control human PF sera that bound to canine epidermis, three (57%) contained IgG autoantibodies that recognized ectopically expressed canine dsg1 with a membrane and punctate pattern. Out of 83 canine PF sera only five (6%) contained IgG that recognized canine dsg1. Consistent with findings for human PF sera obtained in this study, autoantibody binding was conformation- and glycosylation-dependent as demonstrated by calcium chelation with EDTA and tunicamycin or wheat germ agglutinin treatment, respectively. In conclusion, these studies establish canine dsg1 as a minor autoantigen for canine PF. Antigenic epitopes appear to be conformation- and glycosylation-dependent