Shdid C.A.,New York University |
Hajali M.,Pure Technologies
Journal of Computing in Civil Engineering
Drilled shaft foundations are increasingly being used to support various types of buildings and infrastructure facilities. The load carrying capacity of these drilled shafts is largely dependent on their diameter. The large loads carried by such structural elements make quality control and assurance of their diameters during construction extremely critical. Current methods adopted by the industry for measuring drilled shaft diameters during construction depend on discrete points of concrete volumetric measurements that lack both accuracy and continuity. An empirical model is developed and presented in this paper for computing the diameter of drilled shaft foundations that overcomes these limitations. The model is developed using signal processing performed on cross-hole sonic logging (CSL) experimental data obtained from three drilled shaft specimens. The model is validated using experimental data obtained from two separate specimens. The research reported in this paper demonstrates that there exists a high correlation between the maximum amplitude of CSL signal frequency and thickness of concrete. The results show that the model is capable of accurately computing the diameter of drilled shafts, with an absolute average error of 2.42%. © 2015 American Society of Civil Engineers. Source
Abi Shdid C.,New York University |
Hajali M.,Pure Technologies
Structure and Infrastructure Engineering
Drilled shafts are a common type of deep foundations used to support a wide array of infrastructure facilities such as bridges, high mast lighting, tanks and communication towers. The deep inaccessible subterranean nature and the construction procedures of drilled shafts result in various types of anomalies; most critical of which being necking and voids. This necking or voids translates to loss of concrete cover around the longitudinal bars and its subsequent exposure to the surrounding soil, leading to corrosion. An experimental study using large-scale drilled shaft samples is presented that evaluates the effect of different percentages of rebar corrosion on the axial load capacity of drilled shaft foundations. Results show that the presence of corrosion in the longitudinal bars affects both the strength and buckling capacity of a shaft, and that a 25% necking or void area will result in more than 60% of axial capacity loss of the shaft over a time period of 20 years. © 2014 Taylor & Francis. Source
Bell G.E.C.,Schiff Associates |
Paulson P.,Pure Technologies
Pipelines 2010: Climbing New Peaks to Infrastructure Reliability - Renew, Rehab, and Reinvest - Proc. of the Pipelines 2010 Conference
Monitoring and condition assessments methods have struggled with discerning the differences between various degradation activities on Prestressed Concrete Cylinder Pipe (PCCP). The accumulated damage due to wire breaks can be estimated and assessed using electromagnetic methods. Wire break activity can be monitored using acoustic methods. Previous work with acoustic methods indicates that it may be possible to determine post wire break, slips and mortar delaminations from acoustic data i. Recent work i indicates that it may be possible to harvest condition assessment information from acoustic data. In this work, above grade sections of PCCP are instrumented and wires systematically cut while acoustic and mechanical distortion data were collected. Instantaneous changes along with relatively long term relaxation of the pipe were monitored. Advance acoustic data process were applied and results correlated with mechanical measurements and observations including, wire breaks (WB), apparent wire slips (WS) and delaminations (DLAM) of the mortar coating. Results of the testing on an instrumented aboveground 48-inch lined cylinder PCCP show that WBs can be distinguished from other mechanical/structural degradation activity including WSs and DLAMs based on the amplitude, time domain characteristics and frequency spectra. The conclusion is therefore that by using acoustic monitoring detections of the early, intermediate and advanced stages of PCCP degradation leading up to failure can be measured, discriminated and acted upon. © 2010 ASCE. Source
Pure Technologies | Date: 2016-05-17
computer software for data acquisition and analytical software that monitors structures to collect data for non destructive testing of structures; instrumentation to acquire data for non destructive testing of critical infrastructure; hardware, namely, electronic sensors for data collection and non destructive testing and analysis of pipelines and computer software for use in real time monitoring. consulting services, namely, acquisition and interpretation of data, providing review and analysis of results, along with recommendations for further action; installation of apparatus for monitoring the physical integrity of structures and interpreting the results; installation services, namely, installation of monitoring equipment which seeks to find rupture of reinforcement in building structures; installation of inspection apparatus for locating defects in pipelines, bridges and physical structures; analysis of data derived from apparatus used for monitoring the physical integrity of infrastructure; engineering services including pipeline inspection, leak detection, and condition assessment of pipelines; training services, namely, training in the installation, operation and monitoring of the computer programs, computer hardware, monitoring systems and inspection technologies for consumers; pipeline inspecting services; detection and location of leaks, stress, corrosion, cracks, broken wires, broken bars, delamination, gas, air pockets in pipework systems; inspection, assessment, monitoring and management of water, wastewater and oil and gas pipelines, bridges and cable support systems; engineering services in the area related to pipeline asset management; consulting services in the area of assessment and non-destructive testing of pipelines; project management services in the field of water, wastewater and oil and gas pipelines; technical analysis and evaluation of measured inspection data from non-destructive testing of physical structures; services for detection and location of leaks, stress, corrosion, cracks, broken wires, broken bars, delamination, gas, air pockets in pipework systems and pipelines.
Pure Technologies | Date: 2016-03-31
computer hardware and software used for non-destructive testing and analysis of metallic pipelines and cylinders.