Explosions consist mainly of pressure waves of various magnitudes rushing at very high speeds. The condition can be replicated by use of explosive charges, a technique well mastered at the University of Rhode Island (see for instance Shukla, Singh, and Zervas [1996]), or more efficiently by use of a shock tube which allows very accurate control of the process. Thus, a shock tube facility was built during the first stage of this project. In the current stage, strong blasts will be imparted to standing plates. Experiments will first be performed on homogeneous structures, such as the metals or plastics currently used in transportation containers. They will then be followed by evaluation of newer composite materials subjected to the same rigorous blasts. Of particular interest are 3D woven S-2 glass fabric preforms and composites, developed and manufactured by 3TEX, Inc. (Cary, North Carolina), that offer high strength in three directions, excellent crack suppression, damage tolerance, ballistic impact resistance, and blast mitigation properties. In this project, these woven glass fabrics are thus proposed for use in transportation. The newer composites are also of further interest in that would the materials found to be stronger, their relatively low density would result in lighter weight vehicles, and therefore present the additional benefit of saving energy.
The research aims at enhancing the reliability of transportation vehicles against sudden dynamic forces by studying their response to these damaging loads, and by developing techniques of strengthening them where vulnerable. Following, are the major objectives to be accomplished in the second stage of this endeavor:
(i) Conduct experiments using shock tube facility to determine effect of blast loading on panels
(ii) Compare the effectiveness of the various materials used in transportation in mitigating blast loading
(iii) Identify new materials and composites, such as S-2 glass fabric preforms and composites, as candidates to be used in truck panels
(iv) Test the blast loading resistance of newer composites
(v) Evaluate the properties traditional and new materials, prior to and following blast loading damage, both statically and dynamically
(vi) Correlate results from advanced 3-D dynamic numerical models subjected to the same sudden transient loadings with those obtained from experiments.
Highway
One of the main purposes of every transportation department nationwide is to improve highway safety. This is indeed essential in light of the well publicized number of human casualties quoted each year. Added to the already existing problems are new threats brought about by criminal elements skilled in the use of explosives. Consequently, this study will attempt to partially remedy against this new safety hazard by seeking materials that might shield transportation vehicles against shattering of their containers. In the latter cases, the resulting dispersion of pieces would further endanger bystanders. The newly established blast loading facility, sponsored in the first stage of this project by the URITC, will be used to test current, as well as more advanced materials for their effectiveness in shielding against explosions.
In the transportation industry, the need often arises to carry materials that may be susceptible to becoming chemically unstable due to high temperatures or sparks. These conditions may be the result of inclement weather, highway accidents, or terrorist activities. The latter scenario has become much too real for, recently, the United States has had to endure a surge of assaults of ever increasing magnitude, against its possessions both here and abroad. Hostilities, previously confined to war, and dictated by traditional rules of war, have now become random acts directed not only against military but also against civilian targets. Thus, the country must constantly be on guard to prevent or at least to minimize the impact of these unexpected attacks. It is therefore essential that scientists and engineers here use technological tools at their disposal to shield the public against these technologically savvy enemies, many of whom having had the benefit of advanced engineering education. One pattern is apparent and common to these now frequent military or terrorist strikes: they are all strategically well positioned or aimed to inflict the maximum possible amount of damage to the immediate surroundings with the unfortunate and inevitable loss of several human lives. Explosives, or some means of detonation have been observed to be the enemy’s weapon of choice. In cases where the fast moving detonation wave were to reach transport vehicles, it would cause numerous cracks and openings into the container, resulting in spills, which are environmentally detrimental, and also present a great hazard to adjacent vehicles and bystanders. Greater dangers may also surface, if parts of the container were to fly off at high speeds. In the first stage of this project, an experimental facility was developed to simulate such violent bursts of energy. In the second and final stage of the project, the newly build blast loading facility will be used to evaluate materials currently in use in the transportation industry, as well as newer composites being proposed for that purpose. The experiments to be conducted will also identify vulnerable locations of these structures, and help develop techniques of strengthening them.
Jan-Feb: Research of materials used in transportation
Feb-Jun: Fabrication of Aluminum and plastic based panel
Feb-Sep: Manufacture of various 3-weave panels
Mar-Oct: Blast loading test of materials
Jun-Nov: Post-mortem static compression and tensile test of materials
Jun-Nov: Dynamic SHPB testing of materials
Apr-Dec: Numerical evaluation
$182,983.32 ($182,983.00 Yearly)
Jim Leblanc - Thesis assistantship
Varun Batra - Thesis assistantship
Michael Conti - Thesis assistantship
This project is the second stage of a project funded by the URITC entitled:
"Experimental Evaluation of Novel Composites for Use in Transport of Explosive Materials."
3-Tex which is currrently co-sponsoring this
project will receive direct feedback on the
performance of their material.
The project will greatly benefit the transportation industry by providing it with
direct data on the blast resistance of the
materials currently in use, as well as on new advanced materials with potential use in transportation.
Safety and security Panels Highway Trucks