1 نهمین همایش صنایع دریایی یکم لغایت سوم آبانماه 1386 نور استان مازندران HEALTH, SAFETYAND ENVIRONMENTAL MANAGEMENT SYSTEM (HSE-MS) DURING HEAVY CONSTRUCTION FOR RISK AND LIABILITY REDUCTION BY INSURANCE COVERAGE METHOD. Abdollah Ardeshir 1, Narges Amirsadoughi 2, Bahram Taheri 3 Health, Safety, Environment, and Quality assurance (HSE-Q) is very pivotal in all phases of a project regardless of the project's size or type. However, it becomes even more important if a project is either strategic or it has significant economic dimensions. HSE-Q Management System is the management system of choice in all of the huge and successful fortune 500 corporations of the world. It basically governs every single project of these corporations from the point of inception to the decommissioning phase. It is in the framework of this strategic management system which the sustainable development of a corporation and its losses due to undesired liabilities can be planned, managed and controlled. This is a very wide multidisciplinary tool of interdisciplinary subjects applicable to a very wide field of activities. Each subject will require its own detailed study and analysis. The focal point of this paper, however deals with construction phase in large construction projects, marine and offshore structures or dam construction on rivers. These projects absorb huge amount of investments and human resources, and are always faced with various types of risks; which lead to loss or damage. Risk analysis assists us to evaluate the needs for safety improvement, selecting and prioritizing remedial and corrective actions, and improving the construction quality procedure. This research deals with identification of transferable risks to insurance companies while the construction is ongoing. For this purpose, the major risks during the construction of offshore structures and dams have been studied from two different aspects, one with regard to the type of structure and second with regard to different constructional and operational components of the structure. Then, the current major risks have been reviewed apart from their types during the construction, which have been reviewed. Since the insurance is one of the risk transferring methods which is a recommended response to identified risks, the various types of risks which are transferable to insurance companies have been discussed. Also, some of the exclusions in the insurance coverage have been introduced.
2 انجمن مهندسی دریایی ایران مجموعه مقالات نهمین همایش صنایع دریایی Finally, by comparing the identified major risks during the construction and current insurance engineering practice in the world, transferable risks which could be covered with insurances are categorized. Awareness of insurance definition methods, terms and conditions enables the contractors to transfer some risks to insurance companies and strengthen themselves in acceptance and mitigation of residual risks. Introduction of insurance coverage of risks will satisfy HSE-MS requirements and inline with risk premium reduction will satisfy more safety criteria for the project. Keywords Hydraulic structure, Risk, Engineering insurances, offshore structures, water barrier, HSE-MS, premium INTRODUCTION The public perception of risk and individual rights is undergoing significant change, especially with the increasing exposure to the blame and claim culture and ongoing demands for more legislative control both in Iran, and elsewhere, particularly in the public and governmental service sectors. Many companies or government organizations now have to face such risks either through their third party exposure or from their own personnel, either as a result of accident or disaffection. The solution to this problem is adoption of a two-prong strategy, reducing the risk and then transferring as much risk as possible to third party insurers. Reduction of risks should be handled through development of a safety management and auditing system, which in turn reduces the risk insurance premiums. These risks are not only operational but to a great extent can move into the financial sector of activities, hence, requiring a robust financial risk management system. In order to specify transferable risks to insurance companies during hydraulic barrier structure construction, different possible risks should be identified. Since, different kinds of hydraulic structures encounter different types of risks during their construction; various types of these structures have been reviewed in Part A. Also, since the construction of various parts faces their own particular risks, the construction points of different parts of hydraulic structures have been studied in part B. Finally, typical risks during the construction of each structure regardless of their types have been categorized in part C.
3 مجموعه مقالات نهمین همایش صنایع دریایی انجمن مهندسی دریایی ایران Part A. SAFETY AND RISK ON DIFFERENT TYPES OF HYDRAULIC STRUCTURES A.1. concrete gravity dams & related risks during their construction Conventional concrete gravity dams are monolithic structures with a triangular cross-section and either a straight or a curved dam axis. They are built in individual sections, whose size is determined by controlling the hydration heat of the concrete. The major risks are the temperature of the concrete during placement, the cement content, the concrete cooling system, and the climatic conditions on site. Conventional concrete gravity dams are extremely robust structures with little exposure to earthquake or overtopping risks. Production and placement of huge amounts of high-quality mass concrete can be considered as two main activities during the construction of this type of dam, in which the occurrence of unpredicted events e.g. heavy rain, landslide, earthquake and development of subsequent structural instability and leakage due to geological changes can make the construction relatively slow and expensive. A.2.Environmental safety of Concrete arch dams and related risks during their construction Unlike concrete gravity dams, whose loadbearing capability is achieved simply by their dead load, the thin concrete shell of arch dams transmits vertical and horizontal loads into the foundation and abutments. Excellent homogeneous rock conditions as well as appropriate ground treatment measures prior to concrete placement are, therefore, imperative to achieve a sound interface between bedrock and concrete abutment. Construction of concrete arch dams is threatened by faulty design, unsophisticated construction equipment, unsafe sites and inexperienced contractors. Owing to the complexity of the works, proper scheduling and work coordination are essential for timely completion of the project. Likewise, quality control, concrete mix-design and its cooling facilities have great importance to achieve the required monolithic structure. Environmental impacts have great importance in this method. Dangers involved in difficult process of rock excavation particularly in steep flanks, faults in needed comprehensive ground treatment measures, and damage to expensive construction equipment are some of the risk factors during the construction of this kind of structures.
4 انجمن مهندسی دریایی ایران مجموعه مقالات نهمین همایش صنایع دریایی A.3. RCC Roller-compacted concrete dams and related safety assessment during their construction The roller-compacted concrete method of building concrete gravity dams was introduced to reduce costs by using less expensive concrete mixes and accelerating the construction process. Unlike the block method, the concrete is placed horizontally using conventional earthmoving equipment. It is delivered to the site surface by trucks or conveyor belts, distributed by bulldozers and compacted by vibro-rollers. In order to achieve impermeability, the dam s upstream and downstream faces are built using conventional concrete. In addition, cement mortar is placed between the horizontal RCC layers. The HSE consideration in this method is to consider the safety aspect of the project performance. Overtopping of the dam during the construction period, cracking and seepage due to faulty design, bad workmanship, and defective materials are some of the main risks in this type of dam. On the other hand, the concrete for RCC dams usually has a low cement content, which reduces the costs and minimizes the problem of hydration heat control. A.4. Rockfill dams with an impervious core & related safety factors during their construction The cross-section of rockfill dams consists of various zones of different permeability. The impervious element is usually a vertical or inclined clay core. The main dam body consists of dumped rockfill with thin transition layers of filter material on both upstream and downstream sides of the impervious clay core. The dam surface on both sides is protected with rip-rap, i.e. layers of large boulders for erosion protection. Inaccurate selection of the core material, filter zones, and rockfill material and thus an inappropriate grading curve, specialized contractors, and overtopping are some of specific risks in this type of dams. Overtopping of rockfill dams will cause considerable damage particularly to the clay core and the filter zones. The HSE aspect for this case is based on environment and safe handling of material. A.5. Earthfill dams & related risks during their construction Earthfill dams can be subdivided into homogeneous and zoned dams. Homogeneous dams are built using materials of the same grading curve and permeability throughout the dam body. Zoned dams consist of materials of differing permeability. The outer shell is of coarse material
5 مجموعه مقالات نهمین همایش صنایع دریایی انجمن مهندسی دریایی ایران and of higher permeability; the inner zones (which may also be regarded as the core) are of fine material with a low permeability, thus guaranteeing the imperviousness of the dam. The transition between the zones is formed by filter zones to prevent the intrusion of fines into other zones. Earthfill dams are dumped in layers each cm thick and compacted according to the technical contract specifications (Proctor density). Since the optimal degree of compaction depends on the water content of the material, work must stop during rainfall. In extreme cases, placed and compacted materials exposed to heavy rainfall must be removed prior to the placement of the next layer. Therefore, Environment is the major safety factor in this case because rainfall is one of the main risks during the construction. Earthfill dams under construction are highly susceptible to water impact of any kind. Heavy rainfall may even cause deep erosion of the unprotected slopes. Overtopping of an earth fill dam, during construction would severely damage or even destroy the dam body. Part B. SAFETY ON DIFFERENT PARTS OF HYDRAULIC STUCTURE In addition to some risks related to dam types, different parts of THE STRUCTURES are exposed to some specific risks during their construction, which will be discussed in the following sections. B.1. Safety consideration for river diversion systems The construction of any offshore structure requires the temporary diversion of the river in order to create a dry environment at the bottom of the valley. The most common method is to construct cofferdams upstream and downstream of the main construction site. The water is diverted through diversion tunnels driven through the flanks of the valley. The height of the cofferdams and the diameter of the diversion tunnels are determined by the required discharge capacity. Also, some risks during the excavation operation of diversion tunnel that are related to soil type, drilling plant & methods of excavation should be considered as common risks. Faulty design is one of the substantial risks in this system. Therefore the main HSE factor is the environment. B.2. Safety due to spillways and bottom outlets In order to safely discharge flood waves, each hydraulic structure has to be equipped with a spillway system. And, the bottom outlet is another important component of that. It is used to
6 انجمن مهندسی دریایی ایران مجموعه مقالات نهمین همایش صنایع دریایی regulate the water level in the pool and even to empty the reservoir completely. Faulty design is a substantial risk in this part. The workmanship as the safety factor is important; production and placement of concrete are other main risks in this part. B.3. Grout curtain For hydraulic and static reasons, the body of a concrete or embankment structure has to be connected to a vertical cut-off wall or a grout curtain, both penetrating deeply into the bedrock. The depth of this impervious element depends on the height of the structure and thus the hydraulic head. The grout curtain can be built either prior to or during the construction works in the form of an accessible gallery to be incorporated into the dam body. Any seepage occurring through the grout curtain after impounding is discharged into the gallery through a drainage system on the downstream side of the curtain. This gallery is also used for post grouting and monitoring purposes. Environment has an offshore safety for in this case, because Soil type, chosen drilling plant & methods for gallery excavation, quality of grout materials & bad workmanship during drilling and grouting are important factors in the construction of this part. B.4. Ancillary works Often, offshore and onshore construction requires the transportation of large quantities of construction material through very difficult and hilly or even mountainous terrain. Therefore, a large number of temporary access roads form an important part of each project. Construction of these roads involves extensive slope cutting, embankment, and sometimes tunneling works. Owing to the temporary nature of the access roads, their surface is not paved and therefore exposed to rainfall and floodwater. So, rainfall can be considered as a major risk. This shows the environment imparts a large factor in risk evaluation. SECTION C. CURRENT RISKS DURING CONSTRUCTION There are many current risks during the construction of dams and pertinent structures which are mentioned in this section. Construction projects of any kind are particularly exposed to natural hazards. Torrential rainfall can cause severe flooding which may exceed the design flood of the river diversion scheme and even overtop the cofferdams. This may result in partial or total destruction of the cofferdams and cause severe damage to the dam structure under construction.
7 مجموعه مقالات نهمین همایش صنایع دریایی انجمن مهندسی دریایی ایران Extreme rainfall often has a major impact on the stability of temporary slopes and unprotected access roads too. (This will increase the risk of health, and environment) Landslides are another natural hazard in these projects. Access roads, temporary structures, storage facilities, and construction equipments are all highly exposed to the landslide hazard if they are situated next to slip prone slopes. Also, Earthquake peril has to be taken into consideration in the design of temporary and permanent structures in any hydraulic project.(therefore loss of human life is at great risk ) Fire is not a major peril for hydraulic projects, but camps, storage facilities, workshops, and construction plant should be equipped with appropriate fire-fighting facilities. The design aspect is of particular relevance to the dam, its associated structures, spillway and the river diversion system. Most dams are located in remote areas. Therefore, the general third party liability exposure is rather low. However, since it is difficult to isolate dam construction activities from rural life, the exposure to third party residents living in the vicinity of dam construction sites, mainly because of the heavy traffic of construction machinery, is considerable.(therefore, we conclude the human health and relate risk must be taken in to consideration ). Hydraulic construction projects involve the deployment of large amounts of sophisticated and expensive plant and equipment. Heavy earthmoving machinery like excavators, dozers, graders, scrapers, dump trucks, and rollers are used for transportation, placement, and compaction of fill material for earth and rockfill dams. The same kind of machinery is used to carry out massive rock excavation works for the respective foundations and the disposal of excavated material. The main exposures are vehicles colliding or toppling over on steep and narrow access roads,(shows the health risk factors) damage caused by rockfalls and landslides, fire, and flood damage. Hydropower plants often require the construction of massive underground works, involving specialized tunneling equipment including tunnel-boring machines. This machinery is particularly exposed to the impact of tunnel collapses and fire again this shows the health and environment risk assessment, The construction of embankment dams often calls for fill materials to be specially processed. This is done in complex crushing and screening plants. Equally, concrete structures need coarse materials for the production of concrete, which are also processed in these plants. In addition, high capacity concrete-mixing plants are necessary to produce mass
8 انجمن مهندسی دریایی ایران مجموعه مقالات نهمین همایش صنایع دریایی concrete. All of these plants are exposed to natural hazards, including flood and landslide, as well as to fire. Finally, the occurrence of any unpredictable event affects project duration time. It makes the loss of profit which could have been achieved if the project had been operated on time. To summarize, some current risks during the construction of all types of hydraulic structure have been categorized herein below: Natural disasters (earthquake, flood, inundation, windstorm, frost, landslide) Fire & lightning Faulty design of body, spillway, stilling basin, diversion tunnel system, powerhouse, hydro mechanical & electromechanical equipment Damage to surrounding property & Third party liability Damage to hydro-mechanical & electromechanical equipment, machinery, plants, and instrumental tools Human error, bad workmanship, defective material Damage to all property in the site, theft, burglary Not complete performance penalties Loss of profit due to delay in operation to employer or contractor in cases that none of them have been responsible for it Any damage during maintenance period Delay penalties Safety Factor Improvement by Risk Reduction Using Proper Insurance Policy Risk transfer is one of the risk response methods and insurance is a tool for risk transferring. Each risk must have some specifications to be covered by insurance. Firstly, the total value of insured subject must be calculable. Secondly the place and time of unpredicted event must be clearly assessed or estimated. Thirdly, loss or damage shall not be due to willful act or gross negligence. Finally the contractor should observe the required safety points. Different engineering insurance policies have been submitted to cover loss or damage during construction of projects. The most common type of insurance for construction period is Contractors' All Risks (CAR) & Comprehensive Project Insurance (CPI). Their basic concepts are to offer comprehensive protection against loss or damage with respect to the contract works, construction plant, equipment and machinery, as well as the third party claims with regard to the property
9 مجموعه مقالات نهمین همایش صنایع دریایی انجمن مهندسی دریایی ایران damage or bodily injury arising in connection with the execution of construction projects, and even loss of profit due to delay in operation due a variety of causes. The CAR & CPI policies may be concluded by principal contractor or sub-contractors and usually should become effective from the commencement day of work, or after the items entered in the schedule of the policy have been uploaded at the site, and should terminate when the structure is completed or any completed part thereof is taken over or put into service. In some projects the contract is turn-key and in some cases a project should become operational and be managed under the contractor s supervision for a pre-specified duration of time. In these cases the termination date of insurance should be extended accordingly up to the final day of contractor s responsibilities. Every hazard which is not specifically excluded should be covered. This means that almost all the sudden or unforeseen losses or damages occurring during the period of insurance to the contractor s property, client s property, other public or private property, the environment, contractor s or client s personnel, or third party liabilities which are insured on the construction site will be indemnified. So, the employers or clients should be aware of insurance exclusions before the contract with insurance companies is signed. The more important causes of losses identifiable under insurance are: Flood, inundation, windstorm, Earthquake Fire, lightning, explosion Theft, burglary Bad workmanship, lack of skill, negligence malicious acts or human error Coverage for third party claims in respect of property damage or bodily injury arising in connection with the construction of dam project Material consequential damage as a result of faulty design & defective materials Plants, machinery and equipment. It covers not only the construction and erection machinery and plant but also the temporary equipment (e.g. camps, stores, scaffolding) installed at a construction or erection site and not only those belonging to the contractors but also to the insured employer. Standing charges (continuing business expenses) including the salaries and wages paid to employees plus the net profit because of delayed commencement of business operation caused by an accident.
10 انجمن مهندسی دریایی ایران مجموعه مقالات نهمین همایش صنایع دریایی The increase in cost of working, i.e., the additional expenditure necessarily and reasonably incurred for avoiding or diminishing a reduction in turnover, revenue or rentals Property belonging to or held in care, custody and control by insured Inland transit The cost of removal of debris is indemnified only if a separate amount for this cover has been included in the total sum insured. In addition, it is possible to extend the period of cover age to include a maintenance period. The cover provided by CAR insurance is subject to a few standard exclusions which the international insurance market usually applies. Also, they are related to project conditions. The exclusions are named in the policy and essentially comprise: Loss or damage due to war or warlike operation, civil commotion of any kind as well as acts on the part of strikers and locked-out persons Loss or damage due to nuclear reaction, nuclear radiation or radioactive contamination Loss or damage due to willful acts or negligence of insured or of his representatives Consequential loss of any kind or description whatsoever, including penalties, losses due to delay, lack of performance, loss of contracts Loss or damage due to faulty design. However, the consequential material damage is covered. The cost of replacement, repair, or rectification of defective material and/or workmanship. However, the consequential material damage is covered. Specially, in hydraulic projects the insurers shall not indemnify the insured in respect of cost resulting from: Measures which become necessary to improve or stabilize ground conditions or for additional sealing or waterproofing Loss or damage caused by the breakdown of dewatering system if such loss or damage could have been avoided by the availability of standard facilities Dewatering unless necessary to reinstate identifiable loss or damage Loss or damage caused by subsidence due to insufficient compaction Alteration in the drilling method or due to unforeseen ground condition during the construction of underground structures Removing material which has been excavated or due to over break in excess of the design profile and/or for refilling cavities resulting there from.
11 مجموعه مقالات نهمین همایش صنایع دریایی انجمن مهندسی دریایی ایران The abandonment or recovery of tunnel-boring machines Deviation from the schedule direction of tunnel drilling Conclusion The major risks associated with construction or operation of any offshore or onshore hydraulic structures, fixed or moving such as dams, harbor structures, offshore rigs and platforms, bridge piers, etc, while very diverse, share many common features. There are some risks which are predictable in all kinds of these structures apart from their types and parts. In this study we indicated the importance of management of risk factors within the framework of a properly designed HSE Management System. In each step the major risks related to Health (H), Safety (S), and Environment (E), and related damage during the construction and operation of projects should be evaluated. The nature of the concrete and embankment dams are so different that makes them encounter different kinds of risks during construction. On the other hand, the construction of various parts of each hydraulic structure faces to related special perils. It is possible to transfer some risks with the required specifications to insurance companies in order the contractor to be able to concentrate on residual risks. Some exclusion which the insurer declares in the insurance documents should be considered. The transferable risks are realized by comparing the identified risks and coverage's that insurance companies are submitted to accept. Now, due to more environmental awareness and summits such as Kyoto summit the risk reduction on the environmental portion of the HSE on these type of project during construction or operation phases has greater weight which must be taken into detailed consideration. REFERENCE 1. Williams, C. A., Smitt, M. L., and Young. P. C. Risk Management and & Insurance, McGraw- Hill, (2005). 2. Wright, John.Construction Insurance, Practice, Law, Reinsurance, and Risk management. (2005). 3. Project Management Institute. Guide to Project Management Body of Knowledge. PMI. (2004). 4. Technical Insurance References, Munich Reinsurance Company, (2005). 1. Dr. Abdollah Ardeshir, Amirkabir Univ. of Technology 2- N arges Amirsadoughi, MS in construction management, MahabGhodss Consulting co. 3- Bhram Taheri, Amirkabir University Research Member, Consulting Engineer.