Comparative analysis of cast in place post tensioned and steelconcrete composite bridge bent caps. Accurately determining the cost of a construction project is a difficult task that needs experience, engineering judgment and scientific principles 3. Different methods are available for the estimator depending on the project stage and information available, and accuracy needed 3. The direct cost of the pier cap alternatives considered herein was estimated for comparison purposes. The following materials would be needed for the construction of the post tensioned bent cap concrete with a 2. Structural engineering is mainly a subdivision of civil engineering in which structural engineers are trained to understand, predict, and calculate the stability. Comparative analysis of castinplace posttensioned and steelconcrete composite bridge bent caps. The EN Eurocodes. The EN Eurocodes are a series of 10 European Standards, EN 1990 EN 1999, providing a common approach for the design of buildings and other civil. MPa grade 6. 0 reinforcing steel grade 2. The construction process would consist of the following activities 1 shoring structure placement until the cap reaches sufficient strength 2 long term closure of traffic in the roadway below the cap until the end of the cap construction process 3 form work 4 rebar cage fabrication and placement performed simultaneously with previous activities 5 placement of additional elements for prestressing tendons ducts and end anchorages, simultaneously with the previous tasks 6 concrete casting with sufficient curing time to achieve the minimum required strength to perform the next two activities 7 tendon placement, stressing and duct grouting and 8 form work and shoring structure removal. For typical moist cured concrete with type I cement, the variation of strength with time is defined in Eq. Considering the 2. MPa and a required strength at post tension jacking of 3. MPa, a minimum duration of 1. The following materials would be needed for the construction of the composite bent cap concrete with a nominal compressive strength of 4. MPa, Grade 6. 0 reinforcing steel and A7. Grade 5. 0 structural steel. The construction process would require a lower number of activities than the post tensioned cap process, as follows 1 concrete slab form work. The steel section is placed on ground and the slab formwork is placed on it, also at ground level 2 slab rebar placement also at ground level 3 slab concrete casting also at ground level. Enough curing time has to be provided prior to removing the form work. Slab form work removal and 5 lifting and placement of the composite cap in place on already built CIP columns Fig. Fig.  1. 5Lifting of composite bent cap. Considering a minimum required concrete strength of 2. MPa for lifting, from Eq. IH 3. 5E highway would have to be closed to traffic during Task 5. Because of the short time required to place the cap on its final position, only one night closure of IH 3. E would be needed. The cost of a project development can be obtained as the summation of the following costs for each of the materials and activities First is direct cost of material, labor and equipment. This cost, provided that the construction process is optimized, should not significantly vary with the construction company performing the work. And second is indirect cost of traffic closure and detour. Two sets of values were needed to estimate the direct cost 1 unit cost for each of the identified materials and activities. The unit costs used in this study were actual average costs. Quantity takeoff for each of the materials and activities. For cost estimation purposes, the previously described activities were grouped in some cases. Articles/Others/18623-RCC-Building-t1.jpg' alt='Composite Steel Concrete Structures Software Engineering' title='Composite Steel Concrete Structures Software Engineering' />The direct cost consequence of the closure of IH 3. E southbound freeway for both cap options lane closure cost and the associated indirect cost of impacted economic activity were also considered herein. For the indirect cost of traffic closure and detour, the following analysis is based on partly site specific and partly general information. The southbound lanes of IH 3. E freeway carry an average daily traffic of 1. A 1. 6 km work zone with a 2. Walnut Hill Lane and Royal Lane until the construction is complete. The travel delay cost is a summation of the following costs 1. Delay cost for passenger vehicles. This cost was based on the estimated unit value of personal travel time for passenger cars 3. The weighted average of travel time values for passenger cars considering both personal and business travel were then computed, and the delay costs for passenger cars on the northbound lanes estimated as 5. Delay cost for trucks. This cost was estimated based on the unit value of truck travel time 3. The delay costs for both single unit and combination trucks on the northbound lanes were then projected as 9. Time related vehicle depreciation cost. The hourly time related depreciation costs for vehicle types were estimated herein 3. The time related depreciation cost for passenger cars, single unit and combination trucks on the northbound lanes were then projected as 5. Freight inventory delay cost. The hourly cost of freight inventory values was obtained from literature 3. Then, the number of loaded freight trucks were estimated 3. Miscellaneous costs were estimated as 2. VOC and 1. 4,6. VOCs are the expenses incurred by road users as a result of vehicle use. Crash costs are associated with work zones and related detours, and are a function of the expected change in the crash rates due to the presence of work zones 4. Based on the above estimates, the grand total cost due to lane closures on I 3. E southbound freeway at the construction site was found as approximately 7. Gantt charts showing the time schedule of construction are presented in Figs. Asco 940 Operators Manual. The total calculated direct costs were 2. Tables 4 and 5, similar for the two alternatives. However, the lane closure cost of closing IH 3. E makes the cast in place option much less economic. It may be noted that the construction of the post tensioned cap would require 2. Fisher Rs 717 Manual Muscle there. However, the composite cap would need only 1. Bomberman 94 Pc'>Bomberman 94 Pc. Therefore, the composite alternative had a significant advantage in terms of construction and traffic disruption times. This is apparent in the total traffic disruption costs for the two alternatives, a very high 8. It is apparent that the traffic disruption cost is the major savings aspect for the latter option. The post tensioned cap option is overall 2. Fig.  1. 6Post tensioned bent cap construction schedule. Fig.  1. 7Composite bent cap construction schedule. Table 4. Post tensioned cap cost estimate. Table 5. Composite cap cost estimate. Above features an analysis performed for the city of Dallas, Texas, in one of the most heavily populated highways in the metroplex, using a Federal Highway Administration program 4. The costs associated with lane closures are multi faceted, and some are difficult to quantify. The main cost factors associated with the traffic impact were included herein. Factors such as noise and its impact on business and local communities are hard to estimate. Another associated factor is emission cost of vehicles. There is no current consensus on how to assign a dollar value to quantify the impacts of each emission pollutant type. Lifetime maintenance cost for the two alternatives were not included herein. Because of the need to periodically restore the corrosion protective coating on the steel cap section, the composite cap would have a higher maintenance cost overall than the post tensioned cap. The expected duration of the construction activities was obtained by surveying construction engineers who worked on the cap project.