Construction of an Abutment - Coursework Example

NAME OF THE STUDENT DATE OF ADMISSION NAME OF THE INSTITUTION UNIT CODE PROJECT MANAGEMENT CONSTRUCTION OF AN ABUTMENT An abutment is a retaining structure normally designed and put up at the edge of a bride to act as support. They often necessary to act as resistant as well as transfer excess weight that may be caused by the lateral earth pressure (Goel & Chopra 2007). Ideally, due to the ongoing projects at Toll Bar End, an abutment with a double pile foundation will be the most appropriate one considering the fact that the area has an A45 Stonebridge highway that is westbound between Toll bar and Stivichall and needs widening as from the Northern Kerb line. With the proposal of having an underpass linking A45 Stonebridge Highway to the A46 Coventry Eastern Bypass at Toll bar End junction, according to Ahmed & Rajaratnam (2000), a retaining wall with abutments at both sides should be constructed in such a way that highway is able to withstand the pressure of the motorists plying the route especially next to the underpass structure. Components of such an abutment includes:- The Back wall:-These are vertical walls that support sprouting from the abutment seats and act as support for the expansion joints of the bridge (Bratley & Schrage 2011) The Footing heel & Toe The Stem The beam seat Bridge Abutment Design Checking of the Stability Determination of the critical reaction from the beam seat; It involves the calculation of the nominal loading on each 1m length of the abutment beam Estimating the length of the back wall; this will depends on the recommended maximum height of the trucks and motor vehicles to use the underpass Estimation of the footing; the footing heel and toe depends on the width of the highway to be constructed Retaining wall and the beam seat design The loads especially the backfill load which will be as a result of the pressure exerted by the external materials such as trucks will be calculated at –rest lateral earth pressure before the construction commences As stated by Thomopoulos (2011), the limit state, which is the inability for the abutments to function, should be taken into consideration too during the construction of the abutment stem (wall). The limit state can either be an ultimate limit state or serviceability limit state. The ultimate limit state is whereby an abutment experiences distress and structural damage as a result of sliding, overall instability or overturning. On the other hand, serviceability limit state is encountered when the abutment is unable to perform its intended design purpose fully due to too much deformation or deteriorations which may be caused by vibration, cracking or the lateral movement pressures. Setting up of the abutment structure Work Breakdown Structure for the Construction of the Bridge Abutment The construction phase will be implementation as indicated in the Work Breakdown Structure (WBS) below:- Estimation of the footing Activity Schedule and Duration & Labour Resource estimation The construction of the bridge abutment in the A45 Stonebridge Highway will require a number of resources including casual labour, equipment and material supplies to be used in the process In estimation of required resources, three areas must be taken into consideration, these includes the inputs, tools and techniques as well as the anticipated output. Input Methods & Tools Output Enterprise Environmental requirements Judgment of the Experts Duration of each activity estimate Firm process assets Analogous estimation Activity based updates Alignment of the project scope Parametric estimation List of construction activities Three-point estimates Activity based updates Reserve analysis Activity resource requirements Resource calendar Project management plan Ideally, duration estimates are often carried based on the fact that there are adequate resources to enable completion of the project in que For instance, in the construction of the bridge apartment in the A45 Stonebridge Highway, all the necessary resources have been mobilized hence the project is expected to take 10 hours in every working day. The casual labors will be working 5 days in a week Determination of the limit States of the Bridge abutment Current Activity Previous Activity Duration Labour Earliest Started Date Determination of the critical reaction from the beam seat 10 100 02/11/2015 Estimating the length of the back wall Estimation of the footing Determination of the critical reaction from the beam seat Estimating the length of the back wall 7 10 70 100 16/11/2015 25/11/2015 Back fill load calculation at “at-rest” lateral earth pressure Estimation of the footing 7 70 09/12/2015 Determination of the limit States of the Bridge abutment Back fill load calculation at “at-rest” lateral earth pressure 5 50 04/01/2016 Setting up of the Abutment Structure Determination of the limit States of the Bridge abutment 5 50 11/01/2016 Precedence Diagram This is a diagram showing nodes representing activities connected by arrows which indicates the dependencies. It normally works in such a way that an activity begins only after completion of the previous activity. For instance activity (1.1) has to be completed before the commencement of activity (1.2) 1.1 1.2 1.3 Path 1 R 2.1 2.2 2.3 Path 2 ES-Earliest Start time of an activity EF-Earliest Finish time of an activity LS-Latest Start time of an activity LF-Latest Finish time of an activity Therefore, Float will be as follows:- Path 1 (Longest critical path duration-Shortest critical path duration) (10 + 7 + 10)- (7+4+7) =9 days Path 2 (Longest critical path duration-Shortest critical path duration) (7+5+5)- (4+3+3) =7 days PART 2 a) Gantt Chart (Attached-Gantt Chart-PM) b) Precedence Diagram Current Activity Previous Activity Duration Labour Earliest Started Date Determination of the critical reaction from the beam seat 10 100 02/11/2015 Estimating the length of the back wall Estimation of the footing Determination of the critical reaction from the beam seat Estimating the length of the back wall 7 10 70 100 16/11/2015 25/11/2015 Back fill load calculation at “at-rest” lateral earth pressure Estimation of the footing 7 70 09/12/2015 Determination of the limit States of the Bridge abutment Back fill load calculation at “at-rest” lateral earth pressure 5 50 01/01/2016 Setting up of the Abutment Structure Determination of the limit States of the Bridge abutment 5 50 08/01/2016 1.1 1.2 1.3 Path 1 2.1 2.2 2.3 Path 2 c) New Completion Date (Attached-Gantt Chart-PM 2) d) Five ways to Amend the Project (Attached-Gantt Chart-PM 2) Usage of the shortest time period to complete a given activity: The time taken in every activity will have to be reduced so as to have enough time for the succeeding activities The available work force can be combined so as to have a maximum output in one activity before proceeding to the next activity, that is, Project Manager A and B both pool their teams together to have one activity acted upon at once. The project managers can outsource some activities such as transportation of materials to the construction site in order to enable them get ample time to work on the necessary activities The team managers should hire or buy effective and enough working tools to enable the casual labors work with speed in order to complete the job within the shortest time possible The project management should consider increasing the workforce based on the ground that the project owner is aware of the delay that the contractor was subjected to, prior to the project commencement. \ BIBLIOGRAPHY Ahmed, F., & Rajaratnam, N. (2000). Observations on flow around bridge abutment. Journal of engineering mechanics, 126(1), 51-59. Bratley, P., Fox, B. L., & Schrage, L. E. (2011). A guide to simulation. Springer Science & Business Media. Clark, W. (1952). The Gantt Chart. London. Goel, R. K., & Chopra, A. K. (2007). Evaluation of bridge abutment capacity and stiffness during earthquakes. Earthquake Spectra, 13(1), 1-23. Golany, B., & Shtub, A. Work Breakdown Structure. Handbook of Industrial Engineering: Technology and Operations Management, Third Edition, 1263-1280. Hartley, H. O., & Wortham, A. W. (1966). A statistical theory for PERT critical path analysis. Management Science, 12(10), B-469. Maloney, J. (2012). Work Breakdown Structure. Maylor, H. (2001). Beyond the Gantt chart: Project management moving on. European Management Journal, 19(1), 92-100. Meyringer, M. (2006). U.S. Patent No. 7,050,056. Washington, DC: U.S. Patent and Trademark Office. Thomopoulos, N. T. (2011). Mixed model line balancing with smoothed station assignments. Management science, 16(9), 593-603. Read More