Ex Parte Gulbenkian

Board of Patent Appeals and Interferences

Sep 13, 2007

10370634 (B.P.A.I. Sep. 13, 2007)

The opinion in support of the decision being entered today
is not binding precedent of the Board.

UNITED STATES PATENT AND TRADEMARK OFFICE
__________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
__________

Ex parte JACQUES GULBENKIAN
__________

Appeal 2007-2596
Application 10/370,634
Technology Center 3600
__________

Decided: September 13, 2007
__________

Before ERIC GRIMES, LORA M. GREEN, and RICHARD M.
LEBOVITZ, Administrative Patent Judges.

GRIMES, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 involving claims to a
post-tensioning system for concrete structures. The Examiner has rejected
the claims as anticipated and obvious. We have jurisdiction under 35 U.S.C.
§ 6(b). We reverse the anticipation rejection, vacate the appealed
obviousness rejections, and enter new obviousness rejections under 37
C.F.R. § 41.50(b).
Appeal 2007-2596
Application 10/370,634

BACKGROUND
“Post-tensioning of concrete structures has been known in the art for
many years. In post-tensioning, tendons are placed through a concrete
structure and then tensioned using hydraulic jacks in order to place the
concrete structure under compression” (Specification 1). A pervasive
problem with post-tensioned structures “is corrosion of the tendons, which
results in degradation in the strength of the structure. In general, a filler
material such as grout or grease has been used in the prior art in order to
attempt to protect the tendons against corrosion” (id.).
The Specification discloses a post-tensioning method that uses “a
tubular structure configured and dimensioned to provide a continuous void
through a concrete structure, first and second anchor members disposed at
opposite ends of the tubular structure, and at least one stainless steel strand
extending through the tubular structure and secured under tension between
the anchor members” (id. at 2). The Specification discloses that “[t]he
anchor members are mounted to close and maintain the void with the void
being unfilled such that the strand may be easily removed and replaced for
inspection and maintenance” (id.). Using stainless steel strands “reduces or
eliminates corrosion such that the use of grout, grease or other filler
materials are not required for protection of the cables” (id. at 3).
DISCUSSION
1. CLAIMS
Claims 1-7 and 13-23 are on appeal. Claims 1 and 13 are
representative and read as follows:
1. A post-tensioning system for concrete structures,
comprising:
2
Appeal 2007-2596
Application 10/370,634

a tubular structure configured and dimensioned to
provide a continuous void through a concrete structure, said
void being unfilled;
first and second anchor members disposed at opposite
ends of said tubular structure; and
at least one stainless steel strand extending through said
tubular structure and secured under tension between said anchor
members, said anchor members being mounted to at least
substantially close and maintain said void.

13. A post-tensioned concrete structure, comprising:
a concrete member;
a tubular structure defining a void through said concrete
member;
at least one tensioned stainless steel strand passing
through said void and anchored at opposite ends of the member,
wherein said void is unfilled.

Thus, claim 1 is directed to a system for post-tensioning concrete
structures. The system has a tubular structure that provides an unfilled void
through a concrete structure, first and second anchor members at the ends of
the tubular structure, and at least one tensioned stainless steel strand that
extends through the tubular structure. The anchor members are mounted
such that they substantially maintain and close the void.
Claim 13 is directed to a post-tensioned concrete structure that
contains certain elements of the system recited in claim 1. Specifically,
claim 13’s post-tensioned structure has a tubular structure that defines a void
through the concrete member, and at least one tensioned stainless steel
strand that passes through the void and is anchored on opposite sides of the
member.
3
Appeal 2007-2596
Application 10/370,634

2. PRIOR ART
The Examiner relies on the following references:
Klein US 2,837,776 Jun. 10, 1958
Hunter US 3,437,359 Apr. 8, 1969
Lüthi US 5,469,677 Nov. 28, 1995
3. ANTICIPATION
Claims 13, 14, and 21 stand rejected under 35 U.S.C. § 102(b) as
anticipated by Klein (Answer 3).
The Examiner cites Figure 2 of Klein as disclosing a post-tensioned
concrete structure with concrete members 10, 12, 14, and 16, “a tubular
structure 26 . . . defining an unfilled void through the concrete member, at
least one tensioned stainless steel strand 17 . . . passing through the void and
anchored at opposite ends of the concrete member” (Final Rejection 2). The
Examiner states that the “anchor members 19, 21 [are] secured to the at least
one steel strand at each end of the concrete member wherein the concrete
member is compressed by the stainless steel strand” (id.).
Appellant argues that Klein’s building is not a “post-tensioned”
structure, as that term is understood by those skilled in the art (Br. 12-13).1
Rather than compressing a concrete member, Appellant argues, “Klein's
tensioned stranded wire structures 17 freely extend through vertical passages
26 of intermediate stories 12. They are anchored at lower story 10 and roof
14; however, the tension allows for the stretching of compression springs 20,
not compression of lower story 10 and roof 14” (id. at 13).

1 Appeal Brief filed August 3, 2006.
4
Appeal 2007-2596
Application 10/370,634

The Examiner responds that when claim 13 is given its broadest
reasonable interpretation it encompasses “a concrete structure subsequently
tightened to a desire[d] degree” (Answer 5). The Examiner argues that,
given that interpretation, Klein anticipates claim 13 because it discloses a
concrete structure, “i.e. the multi-story parking garage of Figure 1, wherein
the perimeter of the structure has a plurality of stainless steel strands passing
through each floor and fixed to the structure's lower story 10 and roof 14.
These stainless steel strands are then tightened by turnbuckle 18 to tension
the structure along [the] columns” (id.).
For a reference to anticipate a claim “[e]very element of the claimed
invention must be literally present, arranged as in the claim.” Richardson v.
Suzuki Motor Co., 868 F.2d 1226, 1236 (Fed. Cir. 1989). In the instant case,
claim 13 recites a concrete member with a tubular structure that defines a
void through the member. Claim 13’s concrete structure also has a
tensioned stainless steel strand that passes through the void, and is
“anchored at opposite ends of the member” (emphasis added). Thus, claim
13 requires the stainless steel strand to be anchored at the ends of the same
concrete member that has the tubular void.
Klein discloses a vertical wall construction “especially suited for large
parking garages” (Klein, col. 1, ll. 17-18). In Klein’s construction method a
building’s outer walls are constructed of serially spaced vertical stainless
steel wires that are anchored to the building’s top and bottom stories (id. at
col. 1, l. 64 to col. 2, l. 22). “The floor of each intermediate story contains a
vertical passage 26 through which the stranded wire structure freely
extends” (id. at col. 2, ll. 6-8).
5
Appeal 2007-2596
Application 10/370,634

Figure 2 of Klein shows a side view of such a structure. Wire 17
extends from the anchor 19 in a concrete member 14 at the building’s top
story, through a vertical passage 26 in a concrete member 12 in an
intermediate story, to an anchor 21 in a concrete member 10 at the bottom
story. As is evident from Figure 2, the anchors 19 and 21 are not at the ends
of the same concrete member 12 that contains the void, but are attached to
different members.
Thus, Klein does not disclose the claimed elements in the manner
arranged in claim 13. We therefore agree with Appellant that Klein does not
anticipate claim 13, and reverse the Examiner’s anticipation rejection of that
claim, and its dependent claims 14 and 21.
4. OBVIOUSNESS -- APPEALED REJECTIONS
Claims 1, 2, 7, 15-20, 22, and 23 stand rejected under 35 U.S.C. § 103
as obvious over Hunter and Klein (Answer 3). Claims 3-6 stand rejected
under 35 U.S.C. § 103 as obvious over Hunter and Klein, and further in view
of Lüthi (Answer 11).
The Examiner cites Hunter as disclosing “a post-tensioned concrete
structure that is basically the same as that recited in claims 1, 2, 7, 15-20, 22,
and 23 except that the structure lacks an unfilled void and stainless steel
strands” (Final Rejection 3). The Examiner reasons that it would have been
obvious to modify Hunter’s concrete structure to have those features “in
view of the suggestion in Klein that the concrete structure tensioned via
stainless steel strands may absorb the impact of an automobile traveling 40
M.P.H. and the unfilled void tubular structure allow for the damaged strands
to be removed and replaced” (id. at 4).
6
Appeal 2007-2596
Application 10/370,634

Appellant argues that Klein’s teachings are not applicable to Hunter’s
post-tensioning methods because Klein uses the wire strands to absorb the
impact of automobile collisions, not to compress concrete structures (Br.
16). Appellant’s argument raises serious questions as to whether the
Examiner’s combination of Hunter and Klein is adequate to establish a
prima facie case of obviousness. However, because we believe that the
Examiner has not relied on all of Hunter’s pertinent disclosures, we vacate
the Examiner’s rejection of claims 1, 2, 7, 15-20, 22, and 23 over Hunter and
Klein, and enter a new ground of rejection set forth below.
The Examiner’s obviousness rejections of claims 3-6 ultimately rely
on the same combination of Hunter with Klein (see Answer 3). We also
vacate those rejections in view of the new ground of rejection set forth
below.
5. OBVIOUSNESS -- CLAIMS 1, 2, 7, AND 13-23
Under the provisions of 37 C.F.R. § 41.50(b), we enter the following
new ground of rejection: claims 1, 2, 7, and 13-23 are rejected under 35
U.S.C. § 103 as obvious over Hunter.
Hunter discloses a post-tensioning system for concrete structures that
has “a tendon and anchor assembly [with] a wire head on each wire of the
tendon in a particular configuration and with a specific controlled
relationship with the anchor seat such that the entire force of the wire head
against the seat is in the direction parallel to the longitudinal axis of the
wire” (Hunter, col. 3, ll. 54-58). Figure 1 shows an example of Hunter’s
post-tensioning assembly, in which “[t]he tendon is formed of a plurality of
wires 14 extended through an anchor member 10 . . . . The tendon extends
7
Appeal 2007-2596
Application 10/370,634

through the concrete slab 24 being post-tensioned within a conduit 21 and
through the bearing plate 22 which is in bearing engagement with the
concrete slab” (id. at col. 3, ll. 62-70).
Hunter’s Figure 1 shows the conduit having a socket structure, as
recited in claim 7, where it meets the bearing plate 22. The anchor member
10 appears to substantially close the end of the conduit’s socket structure, as
recited in claims 1 and 17. Hunter also teaches that post-tensioning uses
“tendons [that] are extended through bearing plates which are positioned
against opposite edges of the slab” (Hunter, col. 1, ll. 59-61). Thus, Hunter
teaches “anchor members disposed at opposite ends” of the structure (claim
1) or “anchored at opposite ends of the member” (claim 13).
Hunter’s conduit meets the limitations in independent claims 1, 13,
and 17 requiring a tubular structure that defines a void. Because Hunter
does not disclose that the conduit has anything in it, other than the tendon,
Hunter also meets the limitation that the void is unfilled.
To form the tendons, Hunter discloses wire made of “normally .8
carbon, .7 manganese, .2 silicon analysis, hot rolled, cold drawn steel” (id. at
col. 4, ll. 13-15). Thus, Hunter differs from the claims in that Hunter does
not use stainless steel.
Recently addressing the issue of obviousness, the United States
Supreme Court reaffirmed the conclusion “that when a patent ‘simply
arranges old elements with each performing the same function it had been
known to perform’ and yields no more than one would expect from such an
arrangement, the combination is obvious.” KSR Int'l v. Teleflex Inc., 127 S.
Ct. 1727, 1740 (2007) (quoting Sakraida v. AG Pro, Inc., 425 U.S. 273, 282
8
Appeal 2007-2596
Application 10/370,634

(1976)). The Court also stated that it is obvious to choose from among
known equivalents:
When there is a design need or market pressure to solve a
problem and there are a finite number of identified, predictable
solutions, a person of ordinary skill has good reason to pursue
the known options within his or her technical grasp. If this
leads to the anticipated success, it is likely the product not of
innovation but of ordinary skill and common sense. In that
instance the fact that a combination was obvious to try might
show that is was obvious under § 103.
Id. at 1742.
In the instant case, having been advised by Hunter that carbon steel
was useful for making pre-tensioning tendons, one of ordinary skill would
have reasoned that stainless steel would be equivalently useful for the same
purpose. We therefore conclude that the claimed use of stainless steel
tendons in post-tensioned concrete structures would have been obvious to
one of ordinary skill at the time the invention was made.
Hunter also does not appear to disclose post-tensioning adjacent
concrete members, as recited in claims 16 and 22. However, being informed
by Hunter that compressing concrete slabs with anchored tendons reinforces
the slabs, one of ordinary skill would have reasoned that compressing
“stacks” of adjacent slabs would reinforce all of the compressed members.
We therefore conclude that using post-tensioning to reinforce adjacent
concrete members in the manner recited in claims 16 and 22 would have
been obvious to one of ordinary skill at the time the invention was made.
We therefore conclude that one of ordinary skill would have
considered claims 1, 2, 7, and 13-23 obvious over Hunter.
9
Appeal 2007-2596
Application 10/370,634

6. OBVIOUSNESS IN VIEW OF HUNTER AND LÜTHI
Under the provisions of 37 C.F.R.§ 41.50(b), we enter the following
new ground of rejection: claims 3-6 are rejected under 35 U.S.C. § 103 as
obvious over Hunter and Lüthi.
Claim 3 recites “[t]he post-tensioning system according to claim 2,
further comprising a cover member disposed over each anchor member.”
Claims 4-6 limit claim 3’s anchor member to a flexible rubber boot, a
poured concrete cap, and a steel cap, respectively.
As discussed above, Hunter renders the post-tensioning system of
claim 2 obvious. Hunter does not disclose a cap over the anchoring
assembly, as recited in claim 3.
However, Lüthi discloses a “stressing anchorage with which optimal
corrosion protection is achieved” (Lüthi, col. 3, ll. 11-13). Lüthi discloses
that the corrosion-protecting device includes a “cap 24 of metal or preferably
of plastic” that covers the anchorage assembly (id. at col. 6, ll. 17-18; see
also Figure 1).
A person of ordinary skill, recognizing from Lüthi that an isolating
cover over a post-tensioning anchorage assembly would protect the
assembly from corrosion, would have recognized the desirability of covering
Hunter’s post-tensioning anchorage assembly in the same manner.
Moreover, one of ordinary skill, recognizing from Lüthi the importance of
isolating the anchoring assembly from outside corrosive forces, would have
considered it desirable to use any material that would accomplish that
isolation, including the rubber of claim 4, the concrete of claim 5, and the
10
Appeal 2007-2596
Application 10/370,634

steel of claim 6. We therefore conclude that one of ordinary skill would
have considered claims 3-6 obvious in view of Hunter and Lüthi.
SUMMARY
We reverse the Examiner’s rejection of claims 13, 14, and 21 under 35
U.S.C. § 102(b) as anticipated by Klein.
We enter a new ground of rejection of claims 1, 2, 7, and 13-23 under
35 U.S.C. § 103, as being obvious over Hunter.
We enter a new ground of rejection of claims 3-6 under 35 U.S.C.
§ 103, as being obvious over Hunter and Lüthi.
TIME PERIOD FOR RESPONSE
This decision contains a new ground of rejection pursuant to 37
C.F.R. § 41.50(b) (effective September 13, 2004, 69 Fed. Reg. 49960
(August 12, 2004), 1286 Off. Gaz. Pat. Office 21 (September 7, 2004)). 37
C.F.R. § 41.50(b) provides “[a] new ground of rejection pursuant to this
paragraph shall not be considered final for judicial review.
37 C.F.R. § 41.50(b) also provides that the Appellant, WITHIN TWO
MONTHS FROM THE DATE OF THE DECISION, must exercise one of
the following two options with respect to the new ground of rejection to
avoid termination of the appeal as to the rejected claims:
(1) Reopen prosecution. Submit an appropriate
amendment of the claims so rejected or new evidence relating
to the claims so rejected, or both, and have the matter
reconsidered by the Examiner, in which event the proceeding
will be remanded to the Examiner . . . .

(2) Request rehearing. Request that the proceeding be
reheard under § 41.52 by the Board upon the same record . . . .

11
Appeal 2007-2596
Application 10/370,634

REVERSED, 37 C.F.R. § 41.50(b)

lbg

MORGAN, LEWIS & BOCKIUS, LLP
2 PALO ALTO SQUARE
3000 EL CAMINO REAL
PALO ALTO CA 94306
12