نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Construction Methods By Ruqaya ALZubaidi

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Chapter 1 Project Planning and Management

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Chapter 1 Project Planning and Management General Information: This chapterdeals with the Planning that is necessary both prior and during the actual construction on an engineering project. Such planning is necessary in order to construct the project within cost and on time. Items need to be planned are: 1. Identification of specific activities of work required and the relationship between them (precedence relationships). 2. The proper sequencing of the specific activities of work so as to complete the project in optimum amount of time. 3. The time of delivery of materials and installed equipment. 4.The types, quantities and duration of construction equipment used.

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Chapter 1 Project Planning and Management 5. The classification and numberof workers needed and periods of time they'll be needed. 6. The amount and timing of financial assistance needed. Construction Activities: Most construction project are divided into specific activities of work, each with specific objective and length of time to accomplish. Each activity has a specific beginning and ending point and may require a specific piece of equipment or a specific trade classification, for example, the construction of a reinforced concrete retaining wall might be divided into the following activities: 1. Lay out site. 2. Excavate earth (machine). 3

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Chapter 1 Project Planning and Management 3. Excavate earth (hand). 4. Build and erect forms. 5. Placing reinforcing steel. 6. Place concrete. 7. Cure concrete. 8. Remove forms. 9. Finish concrete surface. 10.Clean-up site.

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Chapter 2 Factors Affecting the Selection of Construction Equipment

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Ch. 2 Factors Affecting the Selection of ConstructionEquipment The Cost of Owing and Operating Construction Equipment: There are several methods of determining the probable cost of owning and operating construction equipment. No known method will give exact costs under all operating conditions. At best the estimate is only a close approximation of the cost. Kept records for equipment previously used should give information which may be used as a guide for the particular equipment it was used under the same conditions. Factors that affect the cost of owning and operating construction equipment include: 1. The cost of the equipment delivered to the owner. 2. The severity of the conditions under which the equipment is used. 3. The number of hours the equipment is used per year. 4. The number of years the equipment is used. 5. The care with which the owner maintains and repairs the equipment. 6

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Ch. 2 Factors Affecting the Selection of ConstructionEquipment 6. The demand for used equipment when it is sold, which will affect the salvage value. When it is necessary to estimate the cost of owning and operating construction equipment prior to purchasing it, cost records, based on past performance generally will not be available, therefore the following costs should be considered: Ownership Costs: 1.Depreciation cost. 2.Investment Cost. Depreciation: Is the loss in value of a piece of equipment over time, generally caused by wearand tear from use, the profitable owner of equipment must recover this loss during its useful life.

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Ch. 2 Factors Affecting the Selection of ConstructionEquipment the depreciation can be calculated; the most commonly used methods are the following: 1. Straight-line (SL) method. 2. Sum-of-the-years (SOY) method. 3. Declining-balance method. Straight-line method (SL): The equations used are: − Depreciation rate Rm= 1/N − Annual depreciation amount Dm= Rm (P _S) − Book value at year m, BVm = P _ mDm

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Ch. 2 Factors Affecting the Selection of ConstructionEquipment Sum-of-the-years method (SOY): Rm = N _m + 1/SOY SOY = N(N + 1)/2 Dm = Rm (P – S) BVm = P – mDm Declining-balance method: 1. Depreciation rate, R: For 1.25 declining balance (1.25DB)method, R = N /1.25 For 1.50 declining balance (1.50DB)method, R = N / 1.50 For 1.75 declining balance (1.75DB)method, R = N /1.75

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Ch. 2 Factors Affecting the Selection of ConstructionEquipment 2. The allowable depreciation Dm for any year m and any rate R would be: Dm = (BVm-1)R Operating costs 1. Maintenance cost. 2.Repair parts cost. 3.Lubrication and fuel.

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Chapter 4 Tractors and Related Equipment

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Ch.-4 Tractors and Related Equipment Types of Tractors: In selecting a tractor several factors should be considered such as the following: 1. The size required for a given job. 2. The kind of job for which it will be used. 3. The type of footing over which it will operate. 4. The firmness of the haul road. 5. The smoothness of the haul road. 6. The slope of the haul road. 7. The length of the haul road. 8. Finally, the type of work it will do after this job is completed.

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Ch.-4 Tractors and Related Equipment Major Types of Tractors : Crawler Tractors and, Wheel Tractors. Gradability : Gradability is defined as the maximum slope (expressed as a percent) that a crawler or wheel-type tractor (or related equipment) may move up at a uniform speed.

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Ch.-4 Tractors and Related Equipment Bulldozers: The term bulldozer may be used in a broad sense to include both a bulldozer and angledozer. Uses of Bulldozers: 1) Clearing land of timber. 2) Opening up roads through mountains and rocky areas. 3) Moving earth for haul distances up to approximately 100m. 4) Helping load tractor-pulled scrapers. 5) Spreading earth fill. 6) Clearing construction sites. 7) Maintaining haul roads.

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Ch.-4 Tractors and Related Equipment Front-End Loaders: Front end loaders are used extensively in construction work to handle and transport bulk materials, such as earth and rock, to load trucks, to excavate earth, as bulldozers….etc. they are satisfactory and economical when used for such purposes.

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Chapter 5 Soil Stabilization and Compaction

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Ch. 5 Soil Stabilization and Compaction Soil Stabilization and Compaction Soils are used to support structures, to support pavement for highways, airport and dams. Some types of soils may be used in their natural state, while others may be excavated, processed, and compacted in order to serve their purpose, so the properties, characteristics, and behavior of soil must be known in order to design or construct projects involving the use of soils. Soil Stabilization Stabilization may be applied to the soil in its natural position or as it is placed in a fill. Also, stabilization may be applied to the sub grade, sub base, or base materials.

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Ch. 5 Soil Stabilization and Compaction Methods of Soils Stabilization Include the Following Operations:- 1.Blending and mixing heterogeneous soils to produce more homogenous soils. 2. Stabilizing soils with hydrated lime. 3. Asphalt-soil stabilization: Asphalt such as Mc-3 or Rc-3 are mixed with granular soils, in amounts of 5 to 7 percent of the volume of soil. 4. Cement-soil stabilization

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Ch. 5 Soil Stabilization and Compaction Specifications for Compacting Soils Specifications may be one of the following types: - Method only. - Method and end result. - Suggested method and end result. -End result only. Types of Compacting Equipment:- Compaction is attained by applying energy to a soil by one or more of the following methods: 1. Kneading action

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Ch. 5 Soil Stabilization and Compaction 2. Static weight 3. Vibration 4. Impact

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Ch.-5 Excavation Equipment Excavation Equipment The equipment includes the following: Power shovels Backhoes Cranes Trenching machines Wheel-mounted belt loaders

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Ch.-5 Excavation Equipment Optimum Depth of Cut The optimum depth of a cut is the depth which produces the greatest output and at which the dipper comes up with a full load without undue-crowding. The optimum depth of cut varies with class of material (soil) and the size of dipper. The Output of Power Shovels: The output is affected by numerous factors such as the following: 1. Class of material. 2. Depth of cut. 3. Angle of swing.

نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Ch.-5- Excavation Equipment 5. Job condition. 6. Management condition. 7. Size of hauling units. 8. Skills of operator. 9. Physical condition of the shovel.