1.Introduction • The symptoms of failing productivity to help identify which site and which operations need improvement. • It provides the basic understanding necessary to decide on the implementation of productivity improvement attempts using the tools and techniques
Chapter 2A Dấu hiệu suất không hiệu (Symptoms of Failing Productivity) PGS.TS Lương Đức Long ĐH Bach Khoa TPHCM Source: Prof Olomolaiye “Construction productivity management” Longman 2002 1.Introduction • The symptoms of failing productivity to help identify which site and which operations need improvement • It provides the basic understanding necessary to decide on the implementation of productivity improvement attempts using the tools and techniques 2 Symptoms of failing productivity • Identify quickly symptoms to take timely corrective actions • On-site managers should identify the operations needing attention to bring the project back on track (as project failing behind or ahead of planned schedule and cost budgets) 2.1 How to identify which site needs improvement • Three formal assessment tools available for off-site managers to monitor project performance: o Cost monitoring reports o Progress monitoring reports o Formal site meetings How to identify which site needs improvement (2) a) Cost monitoring: • Involving observation and evaluation of cost data, comparison of observed cost data with cost targets and reporting to appropriate managers If overrun the budgeted costs then the management is alerted for closer scrutiny and subsequent corrective action • The overall profit or loss system is intended to compare the overall profit or loss at the end of contract, which is too late for any corrective action on the project • The unit costing method can be used to obtain each resource variance for each activity or bill item, and this kind of detailed system helps cost monitoring of individual operations to find out which specific operations need improvement How to identify which site needs improvement (3) Cost monitoring: • A cost effective system may lie between these two extremes (The overall profit or loss system, The unit costing method can) The contractor should select a suitable degree of sophistication depending on such factors as the size of company, the type of work undertaken, the type of contract, information needed from the system, money the contractor willing to spend • Management should guard against the possible shortcoming of schedule progress reporting 2.1 How to identify which site needs improvement (3) b) Progress monitoring • Involving comparison of actual physical progress with planned progress • Management should guard against the possible shortcoming of schedule progress reporting 2.1 How to identify which site needs improvement (4) c) Formal Site Meetings • Are one of the main channels of communication between parties during project execution • In these meetings, the contractor have to present the project progress to the client, consultant or project manager, together with sound justifications for failure to meet the planned progress, compels them to make a detailed study of their own problems • In these meetings, the opportunity given to the contractors to present reasons, justify constraints and point out requirements to be met by other parties enables them to reduce costs 2.2 How to identify which operations needs improvement (1) Some of notable symptoms: • Excessive use of labor overtime to complete a unit quantity of work • Bottlenecks in material flow • High material waste • Frequent plant breakdowns • Work fatigue • Late programme as reported by progress report • Poor quality of workmanship 2.2 How to identify which operations needs improvement (1) Some of notable symptoms: • Excessive use of labor overtime to complete a unit quantity of work • Bottlenecks in material flow • High material waste • Frequent plant breakdowns • Work fatigue • Late programme as reported by progress report • Poor quality of workmanship • Delays to and delays by subcontractors • Excessive errors and mistakes, resulting in repetitive work • Insufficient information to proceed with work • Poor site organization 10 2.2 How to identify which operations needs improvement (2) Some of notable symptoms: • Cost overrun as reported by a detailed cost monitoring system • Poor design of temporary work resulting in safety risk, wastages • Constant employee complaints on certain aspects of operation, facilities, tools or work conditions • Site congestion (obstructions, accidents and waste resource) • Safety risks resulting in slowing down of work or accident 11 2.2 How to identify which operations needs improvement (3) Most of these signals are interdependent, implying that a particular operation needing improvement most likely will have more than one signal; For example, excessive errors and mistake will frequently have excessive labour, material waste, late programme and cost overrun These signals can be picked up by the site management through the following means: -Causal observation -Cost reports -Progress reports -Internal meetings -Scientific observation -Site record 12 2.1 How to identify which site needs improvement • Identify quickly symptoms to take timely corrective actions • On-site managers should identify the operations needing attention to bring the project back on track (as project failing behind or ahead of planned schedule and cost budgets) 13 2.2 How to identify which operations needs improvement (4) -Causal observation: symptoms such as poor quality of workmanship, poor design of temporary work and site congestion are readily seen by casual observation -Cost reports -Progress reports -Internal meetings: often include problems such as bottlenecks in material flow, equipment, fatiguing work, delays to and by subcontractors, insufficient information, employee constant complaints, safety risk and so on -Scientific observations: Include field count, productivity rating, work sampling,… -Site record 14 2.3 CLASSIFICATION OF CONSTRUCTION ACTIVITIES -To reflect the true state of productivity, it is necessary to have a clear understanding of associated work elements, categorized as productive, contributory and unproductive: • Productive activities are work elements directly involved in the actual progress of construction or adding to a unit being constructed For example: pouring concrete; vibrating concrete, loading a truck • Contributory activities are work elements that not directly add to output but required and sometime essential in carrying out an operation For example: handling material at the work place, receiving instructions, reading drawings • Unproductive activities includes either being idle or doing something that is unrelated to the operation For example: walking empty handed, work carried out using wrong tools or wrong procedures, rectifying mistakes and so on 15 Productive activities in bricklaying 16 Contributory activities in bricklaying 17 Unproductive activities in bricklaying 18 ... complete a unit quantity of work • Bottlenecks in material flow • High material waste • Frequent plant breakdowns • Work fatigue • Late programme as reported by progress report • Poor quality of workmanship... complete a unit quantity of work • Bottlenecks in material flow • High material waste • Frequent plant breakdowns • Work fatigue • Late programme as reported by progress report • Poor quality of workmanship... How to identify which operations needs improvement (4) -Causal observation: symptoms such as poor quality of workmanship, poor design of temporary work and site congestion are readily seen by casual