Can anyone explain me about Risk management in construction project site?

Understanding risk management is not a few lines of task. But in short the process of identifying, analyzing, accepting or mitigating of an uncertainty to reach to a decision. Essentially, risk management occurs anytime an investor or fund manager analyzes and attempts to quantify the potential for losses in an investment and then takes the appropriate action (or inaction) given their investment objectives and risk tolerance. Inadequate risk management can result in severe consequences for companies as well as individuals. For example, the recession that began in2008 was largely caused by the loose credit risk management of financial firms. According to PMBOK5 “Project risk is an uncertain event or condition that, if it occurs, has a positive or negative effect on one or more project objectives such as scope, schedule, cost, and quality. A risk may have one or more causes and, if it occurs, it may have one or more impacts. A cause may be a given or potential requirement, assumption, constraint, or condition that creates the possibility of negative or positive outcomes. For example, causes could include the requirement of an environmental permit to do work, or having limited personnel assigned to design the project. The risk is that the permitting agency may take longer than planned to issue a permit; or, in the case of an opportunity, additional development personnel may become available who can participate in design, and they can be assigned to the project. If either of these uncertain events occurs, there may be an impact on the project, scope, cost, schedule, quality, or performance. Risk conditions may include aspects of the project’s or organization’s environment that contribute to project risk, such as immature project management practices, lack of integrated management systems, concurrent multiple projects, or dependency on external participants who are outside the project’s direct control.”

hi - the concepts of project management is not dependant on any sector / industry. The guidelines remain the same for Banking, IT, Construction, healthcare, Aviation, etc. 

So, "Risk Management" steps does not change... just that you add / tweak based on what industry you are into. 

However, since you asked abut Construction inductry, here are some of the factors we need to pay attention to - 

• More detailed planning (ensure all vendors understand the expectations), 
• Alternative approaches (what if a vendor did not turn up with expected service / materials), 
• Protection and safety systems (to ensure safety of workers, safety standards)
• Operation reviews (reviews at regular milestones)
• Regular inspections (to ensure processes are followed effectively)
• Training and skills enhancement (workers / vendors should possess the required skills)
• Permits to work (ensure Government rules are adhered to)
• Procedural changes (Any change should go through proper channel)
• Preventive maintenance (tweak processes such that you do not land into reworking stuff)

• Building Codes accoding to the hazard prone area
• Details of BOQs
• Detail drawing of construction activity

project managing a construction site, your risk assessment includes injury to building workers. What might happen to your project schedule in the event of a serious injury and Health and Safety insisting on the project halting until they’d investigated the circumstances of the injury? In other words, have contingency plans built in to the model so that you can, literally, manage the risks. Then you can move on to identifying the measures you can take to prevent the risks actually occurring or at least reduce the impact of them should they occur. Here you need to have a clearly set out plan of action that will quickly get your project back on track. This means identifying who you are delegating responsibility to in order that the problem arising from the risk is solved or removed with utmost efficiency.

CLASS THE RISK ACCORDING TO THE ORDER OF PRIORITY AND START BY CONTROLLING THE ONCE WITH MAJOR IMPACT AND HIGH RISK.