Paving trials

In 1964, Shell Canada conducted full scale paving trials in Oakville, Ontario and St. Boniface, Manitoba in which the in-service performance of SAS systems were compared with conventional asphaltic concrete using both well graded aggregates and poorly graded sands. The results of these trials are summarized below ... 

A summary of the number of SAS paving trials placed since 1964 are given in Table 1. 

Table 8. Sulfur-Asphalt Road Paving Trials in the Middle East...

Paving Trials. A number of sand-asphalt-sulfur test pavements were constructed in Canada without rolling the mixes. The pavements were designed so that mix durability and field performance variables could be evaluated under actual in-service conditions. 

The results tend to verify the conclusions established earlier by Shell, that as long as mix temperatures are maintained below 300°F, concentrations of H S and SO are well within the safety limits suggested by the American Conference of Governmental Industrial Hygienists [ 29]. All of the field trials conducted both in the United States and Canada utilized conventional batch type hot mix plants and paving equipment. These field sections have been under post-construct ion evaluation for more than four years and are still performing satisfactorily. 

Figure 6. Heated dump body truck developed by Shell Canada, Ltd. used for hauling sand-asphalt-sulfur paving mixtures. [Photographed at the Kenedy County Texas field trials in 1977 (28)].

Preliminary road trials with SC paving have taken place in Canada and the U.S. In Canada, Sulphur Innovations Lts., carried out paving tests with Sulfurcrete (15), and in the U.S. the Southwest Research Institute has done research and development work on Sul phi ex paving under contract to the Federal Highway Administration (15, 38, 39). 

Amato F, Nava S, Lucarelli F, Querol X, Alastuey A, Baldasano JM, Pandolfi M (2010) A comprehensive assessment of PM emissions from paved roads real-world emission factors and intense street cleaning trials. Sci Total Environ 408(20) 4309M318... 

Pasetti MF, Levine MM, Sztein MB. Animal models paving the way for clinical trials of attenuated Salmonella enterica serovar Typhi live oral vaccines and live vectors. Vaccine. 2003 21 401-418. 

PAVE and OPSITE stand out among the published randomized trials of CRT in enrolling patients irrespective of pre-implant ejection fraction. In fact, nearly half of the patients in PAVE had a left ventricular ejection fraction above 45%. Post hoc analysis of PAVE suggests that the majority of the benefit in the trial was confined to the subgroup with a pre-implant ejection fraction of less than 45% (39). However, the opposite pattern was observed in OPSITE. In that trial, the comparative benefit to biventricular pacing was greatest in those patients with normal baseline left ventricular function (40). It is possible that these discordant results reflect the play of chance. A larger trial is necessary to resolve the issue. 

Concerning the Applicatwn of Tlnt s In the pro-history of man, knowledge must have been acquired slowly and laboriously, by trial and error, of the different properties of the many materials that came to his hand. The manipulation of things and their application to everyday uses, particularly in the provision of food, fuel, clothing and shelter, brought a familiarity with their properties and paved the way for later speculations concerning their fundamental nature. 

A sharp increase in price and decrease in availability of sulfur reduced the experimental effort temporarily, but laboratory work based on the above findings continued. Pourable paving mixes were developed containing one-sized sands which could be cast in place without rolling, much as portland cement concrete is handled. Based on satisfactory laboratory findings, a test road was constructed in Richmond, British Columbia in 1970, where a sand—asphalt—sulfur mix was cast between forms (5). The success of this trial, coupled with a decrease in the price of sulfur and the forecast for a long-term world sulfur surplus, led us to initiate an extensive research and development program to exploit sand-asphalt-sulfur mixes as road base and surface materials. 

In 1964, full-scale test sections were laid in Oakville, Ontario and St. Boniface, Manitoba, using conventional asphaltic concrete paving procedures. During these trials, rolling procedures routinely used on... 

In 1970, another field trial was conducted in Richmond, British Columbia where the Thermopave was essentially cast between wooden forms without densifidation or compaction. The successful results achieved on this project indicated that unrolled S-A—S mixes had potential as a paving material, both for surfacing and as a pavement base over a weak subgrade (I). 

The first trial of the R + CHOP combination was a Phase II study in patients (mostly fronthne, some relapsed) with Indolent NHL initiated in April 1994 (Table 5) [45]. Patients received six infusions of the Mab and six cycles of CHOP. This study was intended as a pilot study to define the safety and tolerability of the combination in these patients prior to initiating cKnical trials in aggressive NHL. It paved the way for a subsequent... 

The activities found in the greenhouse were encouraging and paved the way to field trials. A new lead structure had been discovered, the substituents of which were now easily amenable to a systematic variation. 

---