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The Port Mann Bridge/Highway 1 design–build project included the new, ten-lane signature bridge, the south approach in Surrey, and the north approach in Coquitlam as part of British Columbia’s Gate...

An extraordinarily ambitious and complex undertaking, the Hoover Dam Bypass stands as a testament to American ingenuity and engineering prowess.

GW597599 1 is a novel NK-1 antagonist currently under investigation for the treatment of central nervous system disorders and emesis. The initial chemical development synthetic route, derived from the one used by medicinal chemistry, involved several hazardous reagents, gave low yields and produced high levels of waste. Through a targeted process of research and development, application of novel techniques and extensive route scouting, a new synthetic route for GW597599 was developed. This paper reports the optimisation work of the third and last stage in the chemical synthesis of GW597599 and the development of a pilot-plant-suitable process for the manufacturing of optically pure arylpiperazine derivative 1. In particular, the process eliminated the use of triphosgene in the synthesis of an intermediate carbamoyl chloride, substantially enhancing safety, overall yield, and throughput.

GW597599 1 is a novel NK-1 antagonist currently under investigation for the treatment of CNS disorders and emesis. The initial chemical development synthetic route, derived from the one used by medicinal chemistry, involved several hazardous reagents, gave low yields, and produced high levels of wastes. Through a targeted process of research and development, application of novel techniques, and extensive route scouting, a synthetic route for GW597599 has been developed. This paper reports the optimisation work of the second stage in the chemical synthesis of GW597599: the development of a pilot-plant-suitable process for the manufacturing of an optically pure arylpiperazine derivative. In particular, the new process eliminates the need to purchase and store dangerous and expensive borane by generating it in situ and also the need for a chlorinated solvent, thereby improving the safety of the process and substantially reducing the overall waste. The final yield and throughput will be significantly enhanced.

This paper describes the preliminary design process for a state-of -the-art single-tower, cable-stayed solution for the signature span of the San Francisco-Oakland Bay Bridge East Span Seismic Safety Project. This design development was carried out in the spring of 1998 as part of the seismic safety improvement for the vulnerable east spans that were damaged in the Loma Prieta earthquake in 1989. Technically progressive developments include tower shear and tension links, a dual plane splayed stay cable layout, a "double-wide" steel/concrete composite deck system utilizing precast lightweight concrete, and post-tensioned steel elements. This paper describes the design issues, design philosophy, concept development and critical details of the cable-stayed option for this new bridge. (A)

Our hypothesis is that the type of instrument will affect variation in pain assessment. A sample of 269 patients administered the visual analog pain scale (VAS) and the generic quality-of-life instrument, and the SF-36 were evaluated for gender, age, the VAS score and the bodily pain domain of the SF-36 (BP-SF-36) score, primary surgical diagnosis, preoperative or postoperative status, and type of operation. Patients were grouped into preoperative (Preop) and postoperative (postop) status and those with chronic pain (CP) conditions and acute/no pain (AP) conditions. Linear regression analysis showed statistically significant (all P value ≤ 0.0006) correlations between the VAS and BP-SF-36 scores all patients, preoperative patients, postoperative patients, acute pain patients, and chronic pain patients. However, the strength of these correlations were moderate (r values between 0.51 and 0.61). Preoperative had more pain compared with postoperative patients as measured by both the VAS and BP-SF-36 ( P = 0.05). Similarly, chronic pain patients had more pain compared with acute pain patients as measured by both scales ( P < 0.0001). Although there are statistically significant associations between the BP-SF-36 and VAS, the correlations are moderate. Different instruments may measure different aspects of pain and the precision with which pain is measured in surgical patients.

The Port Mann Bridge on Highway 1 in Metro Vancouver links the cities of Surrey and Coquitlam in British Columbia, Canada. A new 10-lane 2.02 km long cable-stayed bridge is being constructed over the Fraser River to replace the existing 5-lane bridge. Twelve of the twenty-five bridge piers will be supported on driven steel pipe piles. As part of the foundation design approach, a full-scale instrumented static pile load test was performed along with dynamic pile testing. The test and reaction piles consist of 75 m long, 1,830 mm diameter by 25 mm thick, open-ended steel pipe piles driven into glacially overridden soil using an APE D-180-42 diesel hammer. A custom-built static load frame and hydraulic jacking system provided incremental compressive loads up to 53 MN on the test pile. Following the compression test, an uplift test to 29 MN was performed. The pile was restruck with a Menck MHU 500T hydraulic hammer 9 days after the uplift test. Evaluation of the pile resistance distribution included impacts of residual load and pile plugging. Pile performance during the static load test indicated that approximately 36 MN was carried in side resistance and approximately 17 MN was provided in base resistance. The static pile load test and dynamic testing of selected production piles enabled the use of increased resistance factors for final design, thereby reducing the number of piles to 255, a reduction of approximately 30 percent.

A dramatic new concrete arch joins the setting of the historic Hoover Dam, spanning the Black Canyon between the States of Arizona and Nevada, USA. This 1060 foot (323 m) long arch span is the 4th longest concrete arch in the world, and the longest in the United States. The scale of concrete construction for the bridge is impressive. Four form travelers advanced to the crown of the cast-in-place arch supported by 88 carefully tuned stay cables, while precast segmental construction was used for the tallest precast columns erected to date.

Diffuse reflectance FT-IR has been used to investigate the chemical processes involved in the deactivation of Na/K 2 CO 3 propene dimerisation catalysts and their reactivation by treatment with hydrogen (hydriding). The data show that deactivation of the catalyst is due to the buildup of an involatile unsaturated hydrocarbon material on the surface of the Na/K 2 CO 3 catalyst. The deactivating hydrocarbon material is removed from the deactivated catalyst by hydriding at elevated temperatures, the rate of removal increasing with temperature. Hydriding initially produces propene, some of which subsequently undergoes hydrogenation to propane. Deuteriding produces a partially deuterated propene, which is converted to a partially deuterated propane with time. The origin of the deactivating hydrocarbon material is probably by polymerisation of the equilibrium mixture of methyl acetylene and allene, which are formed by secondary processes during the dimerisation of propene. Breakdown of the polymer backbone appears to be the process by which propene is formed during hydriding.

Diffuse reflectance FT-IR has been used to investigate the chemical processes involved in the deactivation of Na/K 2 CO 3 propene dimerisation catalysts and their reactivation by treatment with hydrogen (hydriding). The data show that deactivation of the catalyst is due to the buildup of an involatile unsaturated hydrocarbon material on the surface of the Na/K 2 CO 3 catalyst. The deactivating hydrocarbon material is removed from the deactivated catalyst by hydriding at elevated temperatures, the rate of removal increasing with temperature. Hydriding initially produces propene, some of which subsequently undergoes hydrogenation to propane. Deuteriding produces a partially deuterated propene, which is converted to a partially deuterated propane with time. The origin of the deactivating hydrocarbon material is probably by polymerisation of the equilibrium mixture of methyl acetylene and allene, which are formed by secondary processes during the dimerisation of propene. Breakdown of the polymer backbone appears to be the process by which propene is formed during hydriding.

A practical enantioselective synthesis of lamivudine 1 is described. A highly effective dynamic kinetic resolution of the 5-hydroxyoxathiolane, followed by chlorination and introduction of cytosine provides an efficient synthesis of lamivudine.

R f search has produced two major procedures for assessing creep and shrinkage; the ACI 209 method' and the CE$-FJP method.' Laboratory research into concrete creep and shrinkage has been conducted for decades, and excellent analytical procedures for evaluating structures for creep and shrinkage have been presented in the literature.'-5 Creep and shrinkage are factors in the design of a variety of bridge details. (The focus here will he on creep, for its treatment is somewhat more involved than that of shrinkage. However, the conclusions apply to both as elements of time dependent deformations.) Creep affects the setting of bearings and the size of sliding plates or laminated bearing pads, it affects the size and setting of expansion joints, and it affects the amount of girder shortening due to prestress and the corresponding loss of prestress, thereby also affecting the secondary moments in a prestressed girder bridge. The amount and character of creep influences the redistribution of forces in certain , structures where the statical system changes during construction, and can, therefore, play a major role in stress distribution for cornposite construction. Creep must be considered in the context of the entire design. The major effects of creep in concrete bridge structures can be summarized in three categories: — Camber and deflection Prestress loss — Stress redistribution Where stress and strength is concerned, it is general practice to base engineering design on a conservative upper bound of demand, not on average demand. However, with creep we have an interest in both. Camber and deflection control i ,or a free cantilever bridge