On the Drawing Board
Reliable and quantitative nondestructive evaluation (NDE) methods for construction materials of wood, concrete, masonry and structural steel are needed. NSF program director John Scalzi...

Access Tube Characteristics and Neutron Meter Calibration
Neutron meter calibration was found to be influenced by material type, thickness and size of access tube. Meter counts were decreased by an average of 15% for a 20% increase in tube diameter...

Relationship of Soil Type and Chemicals to the Calibration of Neutron Meters
Theory of neutron scattering and moderation in matter explains many of the characteristics of calibration curves of neutron moisture probes. Characteristics include effect of atomic species...

Computation of Unsaturated Soil Parameters Using Upward Infiltration Empirical Data
The relationship between soil moisture content and hydraulic conductivity with the soil tension be defined to simulate unsaturated flow in a porous media. Direct measurements of these...

Movement of Triazine Herbicides and Metolachlor in a Sandy Soil
The movement of atrazine, cyanazine, simazine, and metolachlor was studied in an Evesboro loamy sand soil. Both no-tillage and conventional tillage treatments were used. Atrazine, simazine,...

Design of Steel Transmission Pole Structures
Design of Steel Pole Transmission Structures, ASCE Manual No. 72, provides a uniform basis for the design and fabrication of steel pole structures....

Engineering, Construction, and Operations in Space II
This proceedings, Engineering, Construction and Operations in Space II, consists of the 165 papers presented at Space 90, the Second International...

Rheological Analysis of Fine-Grained Natural Debris-Flow Material
Experiments were conducted on large samples of fine-grained material (?2mm) from a natural debris flow using a wide-gap concentric-cylinder viscometer. The rheological behavior of this...

Flume Experiments on Debris Flow
With the different characteristics of grain motion in debris flow, three layers are vertically divided, i.e., viscous collision layer, inertial collision layer and suspension layer. Both...

Unsteady Flow of Bingham Viscoplastic Material in an Open Channel
An analytic solution for transient flow of a Bingham viscoplastic material in an open channel is presented. The solution for the response to a time-varying pressure gradient predicts shear...

Some Aspects of the Mechanism of Debris Flow
As the first step of the development of a general two-phase flow model for debris flows, a simple granular model, which is considered as a special case of the two-phase flow model, is...

Armor Layer Evolution
This communication presents an analysis of celerity propagation for non-uniform materials. Based on the corresponding flow, sediment transpot and sorting/armoring equations, the celerity...

Longitudinal Surface Profiles of Granular Debris Flows
Longitudinal surface profiles of granular material flowing down an inclined plane were studied by means of theoretical analysis and laboratory experiments. There are two driving forces...

Model of Deposition of Grains from Debris Flow
Rapid deposition of grains from debris flow occurs in a channel whose slope angle decreases abruptly. A model of the deposition is presented on the basis of experiments and theoretical...

Nitrate and Bromide Transport Through a Vadose Zone in New Jersey
Ongoing field experiments on monitoring transport of Sodium Nitrate and Potassium Bromide in the vadose zone over a shallow groundwater table in the coastal plains of New Jersey are discussed....

An Experimental Study of Oil Spreading in Ice Covered Waters
In this paper the experimental procedure and some preliminary observations from a new series of experiments on the mechanism of oil spreading under fragmented ice are presented. Laboratory...

The Effect of Grain Size Distribution on the Entrainment of Interstitial Water into Overland Flow
Non-point source pollution from agricultural runoff is an important environmental problem. This experimental study considers the effect of media heterogeneity on the entrainment of interstitial...

A Mathematical Model for Transport and Mixing of Oil Slick in Rivers
A two-layer two-dimensional mathematical model for transport and mixing of oil in rivers is presented. In this model, oil in the river is considered to consist of a surface slick moving...

Design and Construction of Soil-Cement Drop Structures
Soil-cement has been used as an effective and economical slope protection material for embankment dams and stream banks. This paper describes the use of soil-cement in the construction...

Scour in Non-Cohesive Beds at Culvert Outlets
An empirical relationship was developed to estimate the depth of scour in non-cohesive material at culvert outlets. The scour depth is expressed as a function of mean particle size of...

 

 

 

 

Return to search