SOIL ENGINEERING: TESTING, DESIGN, AND REMEDIATION phần 10 ppsx

16.3 Foundation Construction16.3.1 Drilled Pier Foundation16.3.2 Driven Pile Foundation16.4 Construction Control16.4.1 Field Testing16.4.2 Moisture Control16.4.3 Record-Keeping16.5 The T

F.H Chen, Foundations on Expansive Soils, Elsevier Science, New York, 1988.

Effects of Defects in Composite Materials, STP 836, ASTM, 1984.

P Rainger, Movement Control in Fabric of Buildings, Batsford Academic and Educational, London, 1983.

R Weingardt, All Building Moves — Design for It, Consulting Engineers, New York, 1984.

16.3 Foundation Construction16.3.1 Drilled Pier Foundation16.3.2 Driven Pile Foundation16.4 Construction Control

16.4.1 Field Testing16.4.2 Moisture Control16.4.3 Record-Keeping16.5 The Technician

16.5.1 Qualifications of a Technician16.5.2 Length of Service

References

The final product of an engineering project is a combined effort of the architect, theengineers, and the contractor For an outstanding project, the architects get the honorand credit and will be remembered We all recognize the famous architect, FrankLloyd Wright, yet the builder is seldom mentioned At the same time, if there isproblem in the project the first one to blame is the contractor It is the contractorwho uses substandard material, abuses the specification, ignores the advice of theconsultant, and causes the problems

When damage appears in a structure, foundation failure is at once suspected Thecontractor must prove that the construction complies in every respect with the planand specifications The contractor must produce evidence that foundation qualitycontrol has been followed Quality control begins with the geotechnical investigation

of the site and continues through the construction with proper construction control.The relation between contractor and geotechnical engineer can be illustrated byIrving Youger’s reply to a plaintiff when his cabbages were eaten by the defendant’s goat.You did not have any cabbages,

If you did, they were not eaten.

If they were eaten, it was not by a goat.

If they were eaten by a goat, it was not my goat.

And if it was my goat, he was insane.

Ultimately translated to a foundation failure case, the defense might be postulated as:The contractor was not negligent.

If the contractor were negligent, the geotechnical engineer was comparatively negligent.

Even if the contractor were negligent, the negligence did not cause the failure.The actual theories are more than a little like the crazy goat reference above

In the beginning, all the parties involved in the design and construction of a projectmust share the success or the failure of a project The owner hires the architect Thearchitect in turn hires a variety of engineering services, including the geotechnicalengineer The architect compiles all the information and makes a recommendation

to the owner concerning the design and construction of the project

After the design is accepted, the general contractor is selected to construct theproject The architect and the owner generally share in the responsibility of theselection since both have a vested interest in choosing a qualified contractor capable

of completing the work

In the case of geotechnical engineering, a quality assurance program is generallyaccepted as part of construction This program can include periodic or full-timeobservation and testing as well as documentation of adherence to the recommenda-tions set forth in the soil report

In the case of a subdivision development, the developer sometimes acts as bothowner and contractor The developer hires an in-house architect and sometimes anin-house engineer Most of the time, the only other engineer he seeks is the geotech-nical consultant When the owners of the residence sue the developer, the liabilitywill be entirely on the contractor and sometimes the geotechnical engineer

Pier Drilling The constructions of drilled pier foundation systems are

usu-ally subcontracted to the specialized firms The general tractors seldom interfere with the pier drilling operation,except when there is an overrun or when unexpected prob-lems are encountered

con-Pile Driving The performance of the pile-driving operation is observed by

the geotechnical engineer The general contractor is cerned about the time schedule and cost overrun

con-©2000 CRC Press LLC

16.1.2 O WNER ’ S R ESPONSIBILITY

A contractor may have faithfully performed all the obligations contained in thecontract, including those of the subcontractors — yet the building suffered damageafter occupation Should the contractor be held responsible?

Legally, although the project has been accepted by the owner, that does notrelieve the contractor of responsibility Many buildings have suffered damage longafter occupation, and the contractor as well as the engineers and architect are sued

by the owner The arguments by the defendants are:

The contractor cannot control the maintenance of the building, and if the ownerchose to abuse the building, the responsibility should lie with the owner

The engineer, especially the geotechnical engineer, can only give tions but not insurance; it is up to the insurance company to guarantee the integrity

recommenda-of the structure

The most common maintenance negligence is described in Chapter 15

As an example: a municipal building is founded with drilled pier foundations

in an expansive soil area The front part of the building suffered damage from pieruplifting The owner sues the contractor for poor pier placement and the geotectnicalengineer for assigning insufficient dead load on the pier After many months ofinvestigation, it is suspected that water from excessive lawn watering caused thepier uplift The owner argues against the allegation

It is decided that the owner and the geotechnical engineer should inspect thesubsoil conditions under the crawl space Upon entering the limited entrance intothe crawl space, to the surprise of the owner the ground at the front portion in thecrawl space was flooded The owner agrees to drop all claims

Concrete slabs, placed directly on the ground, are much less expensive thanstructure slabs with no direct contact between slab and ground In an expansive soilarea, geotechnical engineers recommend the use of structural slab, unless the ownerassumes the risk of floor movement In such a case, all slab-bearing partition wallsshould be provided with a void at the bottom, so that uplifting of the slab will notaffect the upper structures The engineer provides the contractor with detailed plans

At a later date, the owner decides to add partitions in the basement The partitionsare placed directly on the floor with no void space underneath Consequently, thelifting of the partition walls causes severe distortion of the upper structure Theowner blames the contractor for such damage The geotechnical engineer is able todetermine that the fault lay with the owner and not the contractor

The American Institute of Architects publishes “General Conditions of the Contractfor Construction” for use by the architect The contents of this document increaseeach year; it is now over 20 pages long in closely typed form With this document,the owner and the architect sign the “Standard Form of Agreement Between Ownerand Architect.”

Before signing the contract, the architect will provide the contractor with alldesigns and drawings concerning the project These include a soil report with logs

of exploratory holes Most construction contract bid documents require a site ination before the contractor bids on the project In such cases, the contractor mustmake a prebid examination as a prerequisite to recovery for a changed condition.This duty of the bidder must involve a site inspection, but generally would notrequire an independent boring or test pit investigation.

exam-However, if the contractor does not agree with the subsoil conditions depicted

by the soil engineer, he should at his own expense conduct a separate subsoilinvestigation In almost every case, the contractor accepts the soil report provided

by the owner

Construction is a risky business Between signing of the construction contractand the ultimate completion, a number of factors invariably impact the project Thecontractor assesses the risks of such factors and includes a contingency factor in thebid to protect himself In such cases where the unanticipated subsoil conditions donot materialize, the contingency factor increases the contractor’s profit If the riskactually encountered exceeds those assumed, the contractor will generally seek toobtain relief by the filing of claims

In order to reduce the number of disputes and claims, owners have included intheir construction contracts provisions for risk-sharing by the owner and the con-tractor These risk-sharing clauses include “Changes,” “Differing Site Conditions,”and “Suspension of Works,” among others

16.2.1 D IFFERING S ITE C ONDITIONS

The contractor shall promptly, and before such conditions are discovered, notify thecontracting officer in writing of subsoil conditions at the site differing materiallyfrom those indicated in the contract

Most contracts allow two types of differing site conditions Type I applies wherethe conditions actually encountered differ from the conditions indicated on thecontract documents This includes the following:

GroundwaterRock and boulderBedrock

Man-made objectsUtilities

SoilsDiscussions on Type I differing site conditions are given in Chapter 17

The Type II differing site conditions are those conditions which are unknownand unusual when compared with conditions customarily encountered in the partic-ular type of work This category of differing site conditions is less frequently allegedand considerably more difficult to prove because the contractor must prove he hasencountered something materially different from the “known” and the usual

In one case, the site for the building of a bridge was flooded because of adiversion of the river by another contractor who was constructing a highwayupstream The court held that the diversion was a changed condition even though ithad occurred after contract award

Basically, where specifications prove impossible or impractical in terms ofachievement, the owner is held liable for the cost incurred by the contractor in trying

to perform as specified Fill placement is the portion of specifications that has causedthe most disputes Defective specification can include the following:

Compaction equipmentMoisture contentNumber of passesDegree of compaction (standard or modified)Thickness of each lift

As an example, the specifications require that the fill be compacted to 100%modified Proctor density, where in the soil report the required density is 95%standard Proctor density The difference between modified and standard Proctordensity that may be obvious to a geotechnical engineer can cause confusion to thearchitect or the contractor The specification requirement and soil report requirementcan lead to considerable change in the cost of site preparation

Foundation construction constitutes an important portion of a project For a site withdifficult subsoil conditions such as high ground water, pockets of fill, expansive orsoft soil, etc., the cost of foundation preparation can be as high as 50% of the totalproject cost Yet both the owner and the general contractor pay more attention tothe above-ground work than the below-ground construction

In the past, construction claims on foundation work were relatively small andfrequently resolved at the field level Nowadays, claims that arise may total aconsiderable percentage of the project cost and are rarely quickly resolved at thefield level Over the years, earthwork and foundation construction claims havebecome more sophisticated in terms of technical arguments and cause and effectrelationships; these are often the prime issues at dispute

Problems with footing foundations are generally limited to conditions of theunder footing support The presence of foreign materials or the loose and uncom-pacted soils beneath the concrete footing pads can easily be corrected.

At the same time, defective piers or piles can constitute a major problem, andthe defective elements may not be detected until after the superstructure is partiallycompleted

16.3.1 D RILLED P IER F OUNDATION

It is this part of operation that gives the general contractor the greatest concern.Defective piers discovered after the building is partly completed can deal the generalcontractor a substantial financial loss Legal involvement can be prolonged, delayingthe completion and sometimes resulting in abandonment of the project

Small-diameter piers on the order of 12 in constitute the major portion ofresidential foundation systems in the Rocky Mountain area Such piers generallyare drilled without any supervision Thousands of such piers are drilled each daywith minimal complaints

Large-diameter piers, in excess of 72 in and more than 100-ft long, are used tosupport major structures in the western U.S Such piers must be handled by expe-rienced drillers under close supervision Typical specifications for large-diameterdrilled piers are as follows:

Pier Embedment — The project plans are indicative of subsoil conditionsand depths where satisfactory bearing material may be encountered Ifsatisfactory material is not encountered at plan elevation, the bottom ofany drill hole may be lowered Alteration of plan depth will be made tocomply with design requirements Raising of the foundation elevation shall

be approved by the engineer If the drilling operation reaches a point wherecaving conditions are encountered, no further drilling will be allowed until

a construction method is employed that will prevent excessive caving Ifsteel casing is proposed, the shell shall be cleaned and shall extend to thetop of the drilled shaft excavation

Cleaning of pier holes — After the completion of the drilled shaft excavationand prior to the placement of the reinforcing steel cage and concrete, allsloughage and other loose material shall be machine-cleaned from theshaft A continuous flight auger or other equipment shall be used forcleaning dry excavation where slurry or ground water is not present Whereslurry or ground water is present, the excavation shall be cleaned with abucket auger or similar type of equipment, as approved by the engineer

Reinforcing Steel — The reinforcing steel cage for the drilled shaft consisting

of longitudinal bars and spiral hooping shall be completely assembled andplaced into the shaft as a unit Spacers shall be inserted at sufficient intervalsalong the shaft to ensure concentric spacing for the entire length of shaft

Concrete Placement — Concrete shall be placed as soon as possible aftercompletion of excavation of the drilled shaft and the reinforcing steelplacement Concrete placement shall be continuous in the shaft to the top

in the specifications The engineer is to determine the adequacy and acceptability

of the drilled shaft

16.3.2 D RIVEN P ILE F OUNDATION

Specifications for pile foundations are more complicated than those for pierfoundations Instead of specifying a generalized condition, it is necessary to studyeach project separately The following case illustrates the difference between thespecified condition and the actual working condition:

Specification — The final pile design required the contractor to pre-drillthrough the compacted fill and gravel into the top of the hard clay stratum.The piles used in the design were 12 ¥ 12 in steel H-piles with 50-ton designcapacity The piles had to be driven by a steam or air-operated hammerdeveloping at least 32,500 ft/lb of energy per blow

Piles had to be driven to an elevation –50 ft unless a resistance of 15 blowsper in was recorded before the tip elevation had been reached If therewas any difficulty attaining the specified tip elevation, the engineer was

to be immediately informed and an alternate procedure was to be adoptedupon his recommendation

Construction phase — The contractor wrote to the owner requesting thatpre-drilling be eliminated The geotechnical engineer agreed to the changebut the responsibility for driving the piles without pre-drilling has to beleft to the piling subcontractor

A test pile was driven with 32,500 ft/lb of energy per blow to tip elevation–51 ft and final blow count 200 blows per foot (16.7 blows per in.) Thepile was loaded to 150 tons and settled 0.5 in It was subsequently loaded

con-A very heavy hammer rated 44,000 ft/lb of energy was brought in Thehammer was much heavier than the specified hammer The job was even-tually completed

The contractor claimed that the 45 days’ delay in completion of the pile-drivingcontract caused a 66-day delay in the project completion The change of conditionclaim exceeded the initial contract amount.

The above case indicates the importance of a thorough geotechnical tion, necessary before a specification is prepared and before the contract is drawn up

General and detailed specifications and drawings describe the conditions that must

be met by the contractor They are the technical basis for all matters regarding theproject, and the contractor is obligated to follow all stated requirements Any changes

to the plans and specifications must be authorized by the designers

The foundation phase of the project is generally covered up The adequacy ofthe performance must be determined during the construction Therefore, most con-tracts provide a section on “Field Inspection.” The owner asks the geotechnicalconsultant to provide an “inspector” to control the performance of the contractor.Contract wording is crucial To the lay person, the distinction between on-siteinspection, supervision, and observation may seem slight, but selecting the correctwording for your contract could determine the outcome of litigation As a generalrule, the architect or engineer on a project does not undertake the day-to-day over-seeing of construction activity; rather, they are responsible for periodic observation.Many contracts nonetheless call for the architect or engineer to supervise duringthe foundation construction phase, and courts have stated that the duty of supervisiongoes far beyond what is normally envisioned by the architect when entering into acontract It is the engineer’s responsibility to ensure that the contract correctly reflectsthe scope of service the consultant anticipates performing

Today we understand that “inspect” is a dirty word Attorneys argue that to

“inspect” implies “warrantee.” Therefore, the geotechnical consultant must beresponsible for the performance of the contractor We now elect to use such words

as “observe,” “examine,” “oversee,” or “supervise.” No matter what word we choose

to use, lawyers may find loopholes where they are able to drag the field person intothe dispute

16.4.1 F IELD T ESTING

In most circumstances, testing is done with a nuclear moisture-density gauge Sandcones and balloon methods are less commonly used The sand cones are sometimesutilized to correlate the accuracy of the nuclear gauge, as described in Chapter 9.Testing frequency is often defined in the specifications Any departure from thetesting frequency must be with the consent of the architect If testing frequency isnot specified, a sufficient number of tests should be taken to demonstrate the densityand moisture content to each layer of fill A general rule of thumb is to take at leastone test for each lift per 1000 ft2 in structural fill; one test per 500 cubic yards inoverlot fill; and one test per 300 linear ft of roadway More tests should be taken atthe start of the project to establish a satisfactory construction procedure A minimum

of three tests should be performed on each visit of the technician If compaction

©2000 CRC Press LLC

problems are encountered, additional tests should be taken to isolate the problem area.Failures must be retested unless the technician is able to verify that the unsatisfactoryareas have been removed Retests should be recorded on the daily observation report

16.4.2 M OISTURE C ONTROL

Prior to placing fill on a natural ground surface, all old fill, topsoil, and vegetationshould be removed The area should then be scarified, moistened if necessary, andcompacted as specified in the plans and specifications This is done to provide auniform base for subsequent fill placement

While being compacted, the material in each layer should be at or near optimummoisture Moisture should be kept uniform throughout the layers at both the surfaceand through the depth of the fill This may require watering the material at theborrow area, watering during the placement, or mixing water with the fill afterplacement The technician should follow the moisture requirements outlined in theplans and specifications

16.4.3 R ECORD -K EEPING

It is important that all correspondence between the geotechnical engineer and thearchitect, the owner, the strucural engineer, the contractor, and any other individualsrelated to the project be kept Even a note or a reminder that initially appears to be

of no consquence may turn out to be an important document in a court of law

A geotechnical consulting firm was sued by the government for failure to pointout what was specified in the defective piers during inspection and for changing thesize of the pier from the plan Upon research on several-year-old records, the firmfound the following document:

“… the owner shall employ a soil engineer to inspect the bearing material, and the piers shall be inspected by the architect immediately prior to placing of concrete…”Also a note from the structural engineer that reads:

“… the contractor had asked for a substitution to use 10-in round piers instead of 8-inch Upon checking the structure engineer approved the change…”

These two records clear the geotechnical engineer of a very serious ity The importance of record-keeping is thus obvious Some even claim that therecords should be kept as long as 10 years after the completion of a project

The technician is the consultant’s representative The technician’s primary role is tosee that the work conforms to the intent of the plans and specifications The tech-nician is primarily interested in results rather than methods, but because methodsaffect results, he or she must be able to detect improper procedures and suggestmore appropriate ones The technician also has the obligation to keep the job moving

smoothly and avoid interference with the construction schedule The observationsmade by the technicians call for tact and judgment Technicians provide advice andmake recommendations to the owner If defects are found in the construction, it isthe technician’s duty to notify the owner so that the error can be corrected As part

of that duty, the technicians keep the contractor apprised of his or her advice to theowner Understanding of the contractor’s problems will ensure a cooperative rela-tionship between the contractor and the technician, but the technician’s primaryresponsibility is to the client

16.5.1 Q UALIFICATIONS OF A T ECHNICIAN

To be a technician, one must be tactful, honest, restrained, firm, alert, and patient

He or she must be knowledgeable about construction procedures, material, andequipment, and use good judgment based on experience, education, and training

A technician may have risen from the ranks of the construction workmen and,

by implication, have little or no academic training All technicians should beacquainted with common construction practices, understand project specifications,and be able to interpret contracts and drawings The technician must be able to makereports and maintain a diary of his observations that includes any warnings andinstructions given to the contractor Such records may turn out to be part of defen-dant’s argument in a court of law

The contractor’s foreman with years of experience can usually tell if the nician has previous experience With an inexperienced technician, the foreman mightwell be able to short-cut any operation without the knowledge of the technician

tech-16.5.2 L ENGTH OF S ERVICE

Geotechnical services are provided on a full- to part-time basis, as determined bythe person who fills out the job order On full-time projects, the technician isresponsible for observation of all work performed On part-time projects, techniciansmust know the extent of the work being performed since their last visit in order toperform the appropriate tests The technician should be satisfied that the workcompleted in his or her absence is satisfactory and watch for errors and deficienciesmade during that time If he or she has any doubt, additional testing should beperformed to verify the extent of any deficiencies

In order to save costs, most owners only allow part-time inspections Part-time orthe so-called “on call” service can be very dangerous A satisfactory report issued bythe technician at that particular visit can be taken as a blanket statement that the entireproject is satisfactory

REFERENCES

Chen and Associates, Field Manual, revised by Kumar and Associates, 1998.

S J Greenfield and C.K Shen, Foundations in Problem Soils, Prentice-Hall, Englewood Cliffs,

NJ, 1992.

Byrum C Lee, Construction Litigation.

17.1.3 Potential Plaintiffs17.2 Scope of Liability Suits17.2.1 Frivolous Suits17.2.2 Contingency Fee17.2.3 Comparative Negligence17.2.4 Joint and Several Liability17.2.5 Punitive Damages

17.3 Change of Conditions17.3.1 Drill Logs17.3.2 Depth to Bedrock17.3.3 Specifications17.4 Expert Witnesses17.4.1 Standard of Care17.4.2 Ethics and Egos17.5 The Outlook

References

Suits against professionals are generally categorized under the term “malpractice.”The legal standard for determining professional negligence requires proof that aperson who is considered by the community to be a professional (as determined byeducation, training, licensing, and/or experience) has failed in rendering service tomeet the standard of ordinary care

Engineers, as professionals, are held to a standard of ordinary skill in theirrendering of service The services of experts are sought because of their specialskills They have a duty to exercise the ordinary skill and competence of members

of their profession and a failure to discharge that duty will subject them to theliability of negligence

Over the years, earthworks and foundation claims have become considerablymore sophisticated in terms of technical arguments, and they are prime issues ofdispute resolution Analyzing and evaluating the facts, in a straightforward andunderstandable way, and presenting an effective defense against these claims requirespecial skills The effectiveness of these efforts governs the success or failure of therespective parties

17.1 LIABILITY CLAIMS

The frequency of claims for design professionals has increased dramatically in thelast 40 years In 1960, there were 12 claims per 100 firms; today, the numberincreased to more than 50

3 The problem of increasing premiums is compensated for by higher ibles and less coverage

deduct-4 The number of firms “going bare” has hit a new record More than 23%are uninsured, up from 19% in 1986

5 Engineering firms turned down 69% more work in 1996 than in 1995because of potential liability exposure

6 Consulting engineering firms have learned that promising new approaches

to engineering solutions can become lightning rods for lawsuits if notsupported by a long record of results

The trend of liability claims is such that:

1 The larger the firm, the greater the exposures

2 Suits are usually filed against the most competent, most successful firms.The incompetent and the one-man firm are seldom involved in litigation

3 More suits are filed against firms with large insurance coverage This iswhat is commonly known as the “deep pocket” phenomenon

It has been suggested that suits against engineers will keep the engineers ontheir toes so that it is possible to screen out the incompetent engineers and keep thebest in the profession In fact, engineers today exercise much more care in avoidingand preventing liability problems than two decades ago Most suits against engineersare not based on technical errors but on minor details involving inconsistencies fromwhich attorneys create big issues

Prior to 1970, geotechnical engineers ranked number one among design als as to the frequency of being sued Owners found that it was easy to blamefoundation movement on structural distress At the same time, it was difficult toprove that the distress is not foundation-related In fact, all insurance companiesrefused to insure geotechnical engineers because of the high risk

profession-©2000 CRC Press LLC

Finally, the Association of Soil and Foundation Engineers, Inc (ASFE) wasfounded The ASFE devoted a substantial portion of its time to development of aliability loss prevention program Geotechnical engineers found that the in-housequality control programs such as those listed below can certainly discourage suits

1 Failure to supervise inexperienced employees — A major portion ofminor error is the work of inexperienced employees Most geotechnicalclaims involve field control Field supervisors sign reports that relieve theresponsibility of the contractors

2 Design changes — Because of the changes requested or required by theowner, the design professional subjected himself to unreasonable timeschedules that do not permit adequate review and checking

3 Contract specification — Architects use out-of-date specifications that

do not reflect actual project conditions Contracts that fail to adequatelydefine the duties and responsibilities of the professional and his profes-sional function create an unnecessary and unwarranted exposure to claims

4 Certification — Typical of the documents being used are those thatrequire consulting engineers to certify their findings “Certify” is a treach-erous word Virtually all professional liability insurers interpret it to be

“a promise made in writing.” As such, it creates a contractual liability,and therefore it is uninsurable

5 Language — Some of the most severe claims brought against engineeringfirms have been the result of simple typographical errors that were notcaught either by the typist or by the person reviewing the report Mostengineers are aware that one does not “inspect” the projects; one only

“examines.” By inspection, one virtually takes over the responsibilities ofthe contractor In report language, one must be very careful in using suchwords as “may” or “can,” and how often one uses the word “determine”instead of “evaluate.”

With the loss prevention program, members of the ASFE are able to drasticallyreduce liability suits Today, the high-test percentage of lawsuits is filed against civilengineers (41%), followed by structural (11%), and mechanical (9%) engineers Theinsurance cost of geotechnical engineers is even lower Insurance companies arenow soliciting business from the geotechnical engineers

17.1.3 P OTENTIAL P LAINTIFFS

While most professionals, such as doctors, lawyers, or dentists can be sued only bytheir clients for their failure to properly perform (in rare cases, a third party), theengineer must protect himself and defend his professional conduct against claims by:The client

A subsequent purchaserThe general contractorSubcontractorsThe contractors’ or subcontractors’ employees

Governmental or quasi-governmental agenciesMembers of the public

Other professional parties to the performance of the work, such as architects,structural engineers, landscape architects, etc

Independent groups such as conservation societies and material or componentsuppliers

This large group of potential plaintiffs creates a special problem for engineers.For geotechnical engineers, the list of potential plaintiffs can be even longer

Almost all liability suits against an engineer start with the familiar sentence that theengineering firm has not met the “standard of care.” Before the turn of the century,engineers were considered immune from liability for their errors By 1900, thisimmunity from negligence liability was largely lost, and architects and engineerswere made to pay damages if they violated their professional duties to a client.The key confusion as to the term “standard of care” is as follows:

1 What constitutes “ordinary skill and competence”? What is considered

“ordinary” to one may not be so ordinary to others

2 What constitutes “fallacy”? In engineering, the concept of “fallacy”implies designs below the factor of safety Most of the suits filed todayare far less serious in nature

3 The term “service” should be emphasized Those who hire engineers arenot justified in expecting “infallibility,” but they can expect reasonablecare and competence They purchase services, not insurance

Professional liability is, in fact, an objective standard imposed upon the sional and measured by a reasonably prudent practice for those engineers in similaractivities and in the same geographic area Thus, it is obvious that the standard changesfrom time to time and from place to place What is acceptable practice today maynot be acceptable tomorrow or may not be acceptable today in another community

profes-17.2.1 F RIVOLOUS S UITS

One of the primary concerns of the design professionals in private practice is thedebilitating financial drain resulting from lawsuits that have no merit or factual basis.Such unfounded lawsuits are commonly referred to as shotgun suits or frivoloussuits, e.g, the plaintiff names anyone and everyone even remotely connected withthe occurrence that caused the injury

After expending a great deal of effort, the engineering community in Coloradosucceeded in enacting a bill to limit frivolous suits However, the presiding judge isthe only one who can decide whether the case is frivolous It has been very rare thatthe status of frivolous suits has been applied

©2000 CRC Press LLC

One way to combat this type of lawsuit is by counter-claiming against both theattorney and the client Another way is counter-claiming for abuse of the civilprocess Both approaches are discouraged by the attorney, as well as by the insurancecompany They prefer to settle the case first Consulting engineers cannot afford tospend the time and money to fight frivolous suits

Of course, the best strategy might be for Congress and the state legislators toadopt the English system of forcing losers in civil suits to pay the winner’s legalfees plus court fees

A geotechnical firm made a foundation recommendation for a new jail in ming After completion, an inmate escaped from his cell and commandeered apickup Upon reaching Montana, the inmate shot and killed the pickup owner Thefamily of the deceased sued the Governor of Wyoming, the jail warden, the architect,the engineer and the geotechnical consulting firm Of course, this was a frivoloussuit The engineer and especially the geotechnical engineer had nothing to do withthe jailbreak, yet it took several months and several thousands of dollars in attorneyfees before the suit was dismissed

Wyo-In Aspen, Colorado, a developer used a soil report for a site apart from hisdevelopment without the knowledge of the geotechnical firm When problemsemerged from his development, he sued the consulting engineer for improper soilinvestigation Again, in order to dismiss such a ridiculous suit, considerable attorneyfees are required to comply with the legal procedures

A design professional who becomes an undeserving defendant, frequently covers that the plaintiff is quite willing to drop the suit for a settlement figure ofseveral thousand dollars Frustrated, angry, and convinced that he is the victim ofextortion but recognizing the harsh realities of the cost of the defense, the designprofessional may accept a settlement offer for purely economic reasons

dis-Such “legal blackmail,” if not put to a stop, actually encourages as much as 35%

of lawsuits against engineers

17.2.2 C ONTINGENCY F EE

Under the current system, if the person bringing suit wins, the attorney receives acontingency fee of about 33% of the award If the person bringing the suit loses,the attorney receives nothing

The argument in favor of this system is that people who otherwise cannot afford

a lawyer can readily obtain one On the other hand, in the case of engineeringmalpractice, such a system encourages owners to sue upon the discovery of a slightfault in the construction The owners understand very well that the damage is slightand that it could have resulted from other causes But his attorney encourages him

to sue by saying “What have you got to lose? If you win, you get two thirds of theaward; if you lose, you don’t have to pay me anything.” The greed factor encouragesthe lawsuit If the contingency fee system is eliminated or modified, it is believedthat more than half of the suits against engineers would not take place Furthermore,the contingency fee system offers the attorney an incentive to sue for greater awardsbecause larger settlements mean larger fees It is seen over and over that home

owners sue the builder, the architect, and the soil engineer, when such suits wouldnever take place without a contingency fee arrangement.

A Gallup survey indicated that 32% of respondents said lawyers should becompensated through contingency fees; almost twice that number believe that law-yers should receive a fixed fee in advance, regardless of whether the case is won.Others believe that lawyers’ fees should be based on the number of hours the lawyersactually work on the case

17.2.3 C OMPARATIVE N EGLIGENCE

As a general rule, when an accident occurs on a construction site, everyone connectedwith the project is brought into the resulting suit Under the contributory negligentrule, the plaintiff should not recover damages that they caused themselves by retain-ing the 50% cutoff for recovery

In comparative negligence jurisdictions, the plaintiff’s own negligence may notbar him from obtaining any recovery at all The owner, however, is only able torecover a judgment for the percentage of the claim that corresponds to the degree

of capability of the defendant for the injuries

In most cases, the design professional’s degree of capability will be found to berelatively small compared to that of the construction contractors and owners Accord-ingly, the change from contributory negligence to comparative negligence, in manycases, will result in a smaller judgment against engineers

It is difficult to assign the percentage of negligence In most cases, geotechnicalengineers are not involved with projects, except for the initial soil reports And inmany cases, the actual construction is essentially different from the preliminaryconcept Yet when the geotechnical engineers are brought into the suit, they cannotescape a percentage of negligence The smallest share is about 5% For a multimil-lion-dollar suit, this 5% can be a considerable amount

17.2.4 J OINT AND S EVERAL L IABILITY

Another major issue is the “joint and several liability” rule This rule, dating fromthe 19th century, holds that where several defendants, either in concurrence orindependently, cause damage to the plaintiff, the plaintiff can recover entire damageawards from any one defendant, usually the one with the “deep pockets.”

An example of comparative negligence is one with the general contractor’s share

at 80%, the structural engineer at 15%, and the geotechnical engineer at 5%, butthe preliminary outcome changed It turned out that the contractor declared bank-ruptcy, the structural engineer carried no insurance, and the geotechnical engineercarried high insurance, so the 5% firm had to pay for the total damage Of coursethis is an extreme case, but it happens Fortunately, many states under “tort reform”have written off this rule A party is now required to pay its share of fault, as assigned

by the jury

Judgments for punitive damages are a major cause of a high increase in courtcases The large amount that may be paid under these categories caused somelawsuits to go to trial that otherwise might have been settled voluntarily.

A basement house was flooded from the rise of perched water The builderinstalled a drain system with a sump pump and repaired the damage with a newcarpet The housewife demanded punitive damages She brought her three children,aged 3 to 10, into court During the testimony, she fainted, and her three childrenrushed to the witness box to console her The entire drama impressed the jury thatthe full punitive request was awarded

The change of conditions clause, or as it is now often called, the differing siteconditions clause, is one of the most significant risk allocation clauses found in aconstruction contract Without the clause, the contractor bears most of the financialrisk associated with the encountering of onerous job-site conditions unforeseeable

at the time of bidding With the clause, the owner accepts that risk

On the other hand, for a highly competitive bidding contract, some contractorsmay intentionally lower the bid in order to get the contract They expect to recoverany loss through arguing about the site conditions; with the change of conditionsawarded to them, they may gain financially

There is no limit to the factual situations giving rise to a changed condition.Typical of the conditions that have been found to qualify as changed conditions thatconcern geotechnical engineers are:

1 The presence of rock or boulders in an excavation area where none orfew were shown on the drill log

2 The encountering of rock or boulders in materially greater quantities or

at different elevations than indicated in the drill log available to bidders

3 The encountering of ground water at higher elevations or in quantities inexcess of those indicated in the data furnished to the bidders

4 The difficulty in adopting a drilled pier system as recommended

5 The elevation of bedrock

6 The necessity of using casings to complete the drilled piers