11

Frequent Variation in Work

Changing nature of work necessitating corrective measures.

· AACE International (2019) [22]

· Amos (2004) [3]

· Mubarak (2010) [2]

· Neely (1999) [10]

12

Contentious Claims

Non-defined work scope and responsibilities, and poor documentation.

· Abdul-Malak et al. (2002) [24]

· Kululanga (2001) [25]

· Lu et al. (2015) [26]

· Stamatiou (2019) [27]

· Vidogah (1998) [28]

13

Unrealistic Planning

Inadequate pre-contract planning resulting in increased scope of effort and extensive as-planned data.

· Golparvar-Fard (2010) [8]

· Kerzner (2009) [18]

· Mubarak (2010) [2]

14

Unforeseen Site Conditions

The difficulty in taking physical measurement under inclement weather.

· Garold (2000) [4]

· Yogeswaran et al. (1998) [30]

15

Extension of Time

Measurements related to time are muddled when time changes.

· AACE International (2019) [22]

· Mubarak (2010) [2]

16

Delays and Disruptions

Progress measurement becomes distorted whenever work is interrupted and prolonged reports also delay decision making process.

· AACE International (2019) [22]

· Garold (2000) [4]

· Golparvar-Fard et al. (2009) [23]

· Kaka (1999) [17]