Minnesota Department of Transportation Overload Field Tests of Standard and Standard Installation Direct Design Reinforced Concrete Pipe Installations

1999 ◽  
Vol 1656 (1) ◽  
pp. 64-72 ◽  
Author(s):  
James J. Hill ◽  
John M. Kurdziel ◽  
Charles R. Nelson ◽  
James A. Nystrom ◽  
Michael S. Sondag
Keyword(s):  
Reinforced Concrete ◽  
Field Tests ◽  
Department Of Transportation ◽  
Direct Design ◽  
Concrete Pipe

Field Performance of Instrumented Concrete Pipe Under Deep Burial

1997 ◽  
Vol 1594 (1) ◽  
pp. 224-234 ◽  
Author(s):  
Glenn A. Hazen ◽  
Shad M. Sargand ◽  
Mohammed Haque ◽  
John O. Hurd
Keyword(s):  
Reinforced Concrete ◽  
Computer Program ◽  
Field Performance ◽  
Concrete Pipes ◽  
Deep Burial ◽  
Direct Design ◽  
Concrete Pipe ◽  
Design Calculations ◽  
Buried Concrete ◽  
Contact Pressures

Two 1.524-m-diameter, reinforced concrete pipes were instrumented to compare field results with design calculations. A computer program, Standard Installation Direct Design, developed by the American Concrete Pipe Association was used to design the pipe. Instrumented pipes were completely monitored until 11.9 m of cover had been placed. Measurements of soil contact pressures and vertical and horizontal deflections continued for 6 months. The computer-simulated and observed responses of the buried concrete pipe installations were compared. Pipe contact pressures measured at the invert were much smaller than those assumed from calculations of thrust and moment. Design moments were conservative compared with the experimentally measured values. Thrusts are difficult to calculate accurately and show large experimental variations.

Early Age Performance of Continuously Reinforced Concrete Pavement with Different Types of Aggregate

1997 ◽  
Vol 1568 (1) ◽  
pp. 35-43
Author(s):  
Yoon-Ho Cho ◽  
Terry Dossey ◽  
B. Frank Mccullough
Keyword(s):  
Reinforced Concrete ◽  
Field Test ◽  
Field Tests ◽  
Concrete Pavement ◽  
Crack Spacing ◽  
Winter Period ◽  
Thermal Coefficient ◽  
Curing Methods ◽  
Pavement Construction ◽  
New Variables

The effect of coarse aggregate on pavement performance has been attributed to the volume of aggregate used in pavement construction. The different patterns of crack development for limestone (LS) and siliceous river gravel (SRG) are a typical example of aggregate-induced variable performance in continuously reinforced concrete pavement (CRCP). An attempt was made to find a reasonable solution for pavements with SRG. As a way to solve the performance problem observed from the SRG pavement, a blended aggregates mixture was suggested. Laboratory and field tests were performed to check the feasibility of their application in pavements. From the laboratory test, a 50:50 blending ratio was suggested after considering the effect on tensile strength and thermal coefficient of expansion. Field test sections were also constructed to verify previous performance observations for the two aggregates and to provide performance data for new variables such as blended aggregates and special curing methods. Unexpectedly, the blended mixture did not improve the performance of SRG pavement; rather it experienced worse cracking than SRG alone. A controlled experiment with additional field test sections is needed to verify or disprove this finding. The only definitive finding was that selection of aggregate in the concrete pavement is a vital consideration for the design of the pavement. The CRCP8 analytical program reasonably predicted crack spacing for both SRG and LS pavements, predicting mean crack spacing of 0.99 m (3.25 ft) for SRG and 1.98 m (6.41 ft) for the limestone. These values are somewhat below the actual spacing observed at 100 days. Data collected after the first winter period will be required to calibrate the program.

Simple Model of Forward Visibility for Snowplow Operators Through Snow and Fog at Night

1997 ◽  
Vol 1585 (1) ◽  
pp. 19-24 ◽  
Author(s):  
John Bullough ◽  
Mark S. Rea
Keyword(s):  
New York ◽  
New York State ◽  
Field Tests ◽  
Line Of Sight ◽  
York State Department ◽  
Light Sources ◽  
Department Of Transportation ◽  
Narrow Beam ◽  
York State ◽  
Beam Type

Backscattered light reflected from falling snow, rain, and fog impairs visibility and can hinder performance of snowplow operators. New York State Department of Transportation snowplow operators cite backscattered glare as an important problem, and many drivers use their own “solutions” to counteract it. A literature review yielded two important conclusions: backscattered light from a lamp in fog and falling snow is reduced, and visibility is improved ( a) as the lamp is moved away from the operator’s line of sight and ( b) with a narrow-beam lamp. Field tests of lighting configurations during inclement weather were conducted to determine the effects of beam type and displacement from the operator’s line of sight on visibility, glare, and satisfaction. On the basis of these data and the literature, a simple mathematical model was developed that predicts the forward-visibility ratings of snowplow operators. This model can be used to guide specifiers in selecting light sources and mounting locations for snowplow operations.

scholarly journals Experimental Campaign to Verify the Suitability of Ultrasound Testing Method for Steel Fiber Reinforced Concrete Fortification Structures

2021 ◽  
Vol 11 (18) ◽  
pp. 8759
Author(s):  
Eva Zezulová ◽  
Kamila Hasilová ◽  
Petr Dvořák ◽  
Branislav Dubec ◽  
Tereza Komárková ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Reinforced Concrete ◽  
Steel Fiber ◽  
Field Tests ◽  
Fiber Reinforced Concrete ◽  
Blast Load ◽  
Fiber Reinforced ◽  
Steel Fiber Reinforced Concrete ◽  
Testing Method ◽  
Ultrasound Testing

Fortification structures, both military and civilian, are designed to resist a blast explosion to some extent. Their technical condition after a blast load must be assessed in a fast and reliable way to enable the users’ decision about the future use of the structure. Preferably, for the assessment of the protective structure, the non-destructive testing method should be used. To assess the suitability of ultrasound testing method for fortification structures built from steel fiber reinforced concrete, an investigation in a laboratory and in situ was conducted, together with numerical simulation and statistical evaluation. The numerical simulation of the blast load of a steel fiber reinforced concrete slab was conducted using multiphysics simulation software with the aim to verify basic parameters of the field experiment. During the field tests, several slabs were loaded by plastic explosive and changes in the structure of the slabs, before and after the blast load, were examined using the ultrasound pass-through method. After the field tests, the slabs were subjected to a destructive laboratory test to determine their residual strength. Subsequently, the data sets obtained from the measurements were tested using functional data analysis. The results from the ultrasound pulse method show that specimens after a dynamic blast load can in some cases increase the strength of their cement matrix.

Lap Weld Strength of Reinforced Concrete Pipe Cages

2017 ◽  
pp. 1-17
Author(s):  
George Hand ◽  
David Schnerch ◽  
Kimberly L. Spahn
Keyword(s):  
Reinforced Concrete ◽  
Weld Strength ◽  
Concrete Pipe

Application of Cement Based Materials for Critical Infrastructure Protection

2015 ◽  
Vol 796 ◽  
pp. 99-110
Author(s):  
Jiří Štoller ◽  
Petr Dvořák
Keyword(s):  
Reinforced Concrete ◽  
High Performance ◽  
Critical Infrastructure ◽  
Field Tests ◽  
Plain Concrete ◽  
Lessons Learned ◽  
Fibre Reinforced Concrete ◽  
Critical Infrastructure Protection ◽  
Infrastructure Protection ◽  
Cement Based Materials

The article describes the characteristics of a selected cement based materials and the possibilities of their use for critical infrastructure protection. The material properties were studied during field tests on slabs made from different materials – plain concrete, fibre reinforced concrete and high performance fibre reinforced concrete. In the article there are also presented lessons-learned of the research team of the military structures laboratory, which is run by the Department of Engineer Technologies at the University of Defence.

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