ST9302-CS 990819Kimley-Horn
and Associates, Inc.
August 19, 1999
Mr. Ken Griffin
City Engineer
City of Coppell
P. O. Box 478
Coppell, TX 75019
Re'
Sandy Lake Road
Contractor Request for
Low Profile Concrete Barrier
KHA No. 061087000
Dear Ken'
The proposed low profile concrete barrier (LPCB) is a system approved and
specified by TxDOT in high speed areas where site distances are of a concern.
Given the high frequency of cross streets, it could very well be that the use of
LPCB's is appropriate for the entire length of barriers.
The LPCB's are 26" wide at the base, 28" at the top and 20" tall. The Type 2
barriers are 33" tall, 27 1/4" wide at the base, tapered to 8" wide at the top and
approximately 9" wide at 20" above the base. Their respective dimensions are
indicated on the attached drawings.
Ed Bell Construction desires to use the LPCB's in order to facilitate concrete
delivery from the existing road. Since these paving operations require flagmen
and other traffic controls implemented by the Contractor, then I am not opposed
to the substitution of LPCB's for Type 2 barriers during the time that paving is
underway and the contractor has flagmen and additional traffic control systems
in place. The Type 2 barriers must be replaced at the completion of paving
operations if conditions so dictate.
Project safety is the sole responsibility of the contractor. The devices and
systems implemented by the contractor should be at the least in accordance with
"state of the art" and standard industry practices. Whenever new or unusual
systems are implemented, then it is appropriate for the City to request
documentation indicating their proper applications.
Ken, I am particularly concerned at the apparent creation of a condition
requiring barriers and the contractor not having barriers on site. This situation
should only occur if alternative traffic control systems are appropriate and
·
TEL 817 335 6511
MET 817 654 4266
FAX 817 335 5070
·
Suite 1100
801Cher~ Street
Fo~Woflh, Texas
76102-6803
Kimley-Horn
and Associates, Inc.
Mr. Ken Griffin, August 19, 1999, Page 2
implemented. I also have minor concerns about recommending payment for a
system that was not in place at the time it was needed. Granted, this is a
relatively small price and an appropriate safety system should be in place for
the duration of the exposure, but I am concerned at even appearing to reward
the contractor for not complying with safety precautions in a timely manner.
In the future I suggest that Coppell consider withholding payment for any
construction items which create risk conditions and for which appropriate safety
systems are not implemented in a timely manner. Payment would be released
on the regular periodic pay estimate following implementation of the
appropriate safety systems.
Please contact me at your convenience should you have any further questions.
Very truly yours,
KIMLEY-HORN AND ASSOCIATES, INC.
Lee K. Allison, P.E.
LKA:pts
Attachment
Copy to:
Stan Phillips, Inspector
Robert Weber, Ed Bell Construction
Mike Martin, Coppell Engineering
P:~610~7.00~ltr\barriers.doc
DELINEATION OF SAFETY END TREATMENTS BARRIER DELINEATION WITH SAFETY GLARE FENCE
~ // ~ will ~ installed sforti~ at I. Leith of S?ety GI~o Fe~ will ~ s~ified else~re in ~ plms. LEGEND
~_3 //// I~g~ of ~ i~ivi~l secti~s of t~=y ~rete traffic ~ ~ic~
: ~rier ~ ~i~ ~y ~e installed so ~ joint be~ ~rrier
crete ~rrier not to excee~ o s~i~ of g raters, ~ri~ refl~tors
are ~t ~essory ~n p~l/bl~s ~e instal le~. ~ ~ ~ Safety ~lare fete
REFLECTORS FOR CONCRETE TRAFFIC
APPROACH[NG*RAFF[C BARRIER, BARREL MOUNTED GUARD FENCE~
~T. s[o~s m~ szo~ AND ATTENUATORS
~-3 Ty~ C refl~t~s ~y ~ instal led usi~ ~ rivets, nuts md bolts,
~ ~ cmstr~tlm ~esive ~ butyl ~r ~esive.
Vert i ca I
j DELI~AT[~ ~-I
P~I If Ty~ C meflect~s ~e s~ified els~re in Ty~ C refl~t~s shall ~ ~e~lifi~ ~d ~11 c~fom to the
- - t~ plms a mlni~ of ~ will ~ installS, color ~ refl~fivify re~irmnts of S~ificatlm o-g-8600.
~less stated else~e in t~ plans~
~o1~ of Tyffi C refl~f~ will N f~ sm as ~ newest e~ li~, reflffit~izatJm of ~tal ~, deli~atim
~e ~vffif ~kiw ~ as dir~t~ by t~ [~J~er. ~ refl~f~s s~ m ~is sfffid ~al I
~ REFLECTORIZATION CONCRETE TRAFFIC BARRIER (OTB) LOW PROFILE CONCRETE BARRIER (LPCB)
~~~ OF METAL DRUMS ~TER[ALS~TESTSD[V[SI~
~ FOR BARREL ~OUNTED ,~s [~s~ ~,~.
~ GUARD FENCE Surf~e ~t AUSTIN, TX
SPECIFICATJ~ REFERENCE TA~E
~TE~[ALS AND TESTS OJVISI~ SPEC[F[CAT[~S
~ ~ -- ~ EPOXY O-g-6~O0
~ 8fri~8 FLAT ~FACE REFLECTJ~ SHEETJ~, TYPE C
~ (~IGM ~ECJFIC INTENSITY) O-g-8~
DELI~AT~ A~ ~JECT ~KER D-9-86~
tim of ~tal ~ us~ to ~t ~rel ~ted ~d f~. flexible-reflective r~ay ~k~ 900~ ~~ ~ ~TATI~
iz~ ~ ~ refl~t~ized ~ite strips, I00 to 200 ~ ~i~. WORK ZONE
T~ first reflect~ized stri~ s~ld st~t within f~ i~s of
~ite s~i~ m eo~ ~ If ~e is o ~-reflect~iz~ s~e Bottler reflectors ~ill ~ instoll~ rely m ~rlers ~si~t~ f~ refl~f~izotlm os cequiced else~e in t~ pl~s.
S~cificotlm D-9-83~ T~ C (High ~iflc [nfmsify).
All drm m ~oj~t ~ill ~ ~. U°xi~ s~ing of refl~t~s is 12 raters f~ CT8 md 6 raters f~ LPCB. ~t refl~t~s to ~rler wi~ cmstructlm o~sive ~ butyl r~r o~slve. ~T~T *~il 1992
I
1-97
APPROACHING TRAFF[C
80TH SLOES ONE SIDE
OU-3
DELINEATION OU-I or
Verti co I
Panel
2"
TROUGH FOR BOLT
REMOVAL AND INSERTION --~
CONNECTION BOLT HOLE
H2 BARS
Vl BARS
Vt BARS
CONNECTION
BOLT HOLES~--.
H2 BARS
20'I 0" USUAL
10'- 0"
10"
30"
V2 BARS
DRAINAGE SLOT
50" 24"~-
11~'' STL. DRNN PIPE
(HOLE GOES THROUGH TO
DRNNAGE SLOT).
~)
H1 BARS
--H1 BARS
PLAN VIEW - TYPE 1
(SYMMETRICAL ABOUT CENTER LINES)
1 V2" NOM. DIA. STL. B ~
--. LIFTING PIPE (LOCATED
o.I
4'- 0" FROM EACH END
SEGMENT).
~DRAJN 2" MAX.
12"
-- Vl BAR
NOTE: CONCRETE ON BOTTOM HALF OF PLAN VIEW
IS REMOVED IN ORDER TO SHOW DETAILS
,--Vl BARS SPACED AT
12" C-C MAXIMUM.
A
ELEVATION - TYPE
(SYMMETRICAL ABOUT CENTER LINES)
4"
SECTION A-A
TROUGH FOR BOLT
REMOVAL AND INSERTION.
WELDED WIRE FABRIC
.3 x 12 - D20 x D20
60 KSIMIN. YIELD
STRENGTH (ASTM A497) ~ .3 ~/4"
SECTION B-B
12" 12"
SIDE VIEW
NOTE: THIS FABRIC OPTION CAN BE USED IN PLACE OF
V1, V2 AND H1 BARS. THE H2 BARS SPECIFIED
ARE STILL REQUIRED.
WELDED WIRE FABRIC OPTIONAL REINFORCING
.38"
NOTE: ALL BENDING OF SHEAR REBAR IS
AT A 2" RADIUS, UNLESS SPECIFIED
OTHERWISE.
4" 15" 4" 21"
H2 BAR(e 5)
(GRADE 60 MIN,)
NOTE: H2 REBAR IS TO BE BENT
AT A 3" RADIUS,
v2 BAR(,, 4) Vl BAR( ,m 4)
REINFORCING STEEL DETAILS
1 ~/z" NOM. DIA. STL.
PIPE FOR CONNECTION
~, 14" /-BOLTS.
2" COVER ~ , 10" ?' 10"
'--~-_ H2 BARS
2" COVER
i ~ 7". '-TROUGH FOR
~ BOLT REMOVAL
V2 BAR ' AND INSERTION.
SECTION A-A
1 I/2" NOM. DIA. STL.
LIFTING PIPE.
28"
./.,, Fco v R'. '.
i~ ~.~ ' ~'"~,-v~ BAR
26"
SECTION B-B
STANDARD
THREADING
26"
STANDARD
USS WASHER,-
GRADE 5. ,,
1 V4" HEX. NUT ~-
CONNECTION BOLT
GENERAL NOTES
1. BARRIER LENGTH SHALL BE 20 FEET ( / ~t INCH) UNLESS OTHERWISE SPECIFIED IN THE PLANS.
2. ALL CONCRETE, REINFORCEMENT, ANCHOR BOLTS,
BLOCKING, ETC., AS SHOWN ARE CONSIDERED AS
PART Of THE BARRIER FOR PAYMENT.
3. ALL CONCRETE SHALL BE CLASS A, C, OR H, UNLESS
OTHERWISE SPECIFIED.
4. ALL REINFORCING STEEL SHALL BE GRADE 40, UNLESS
OTHERWISE SPECIFIED.
5. CHAMFER ALL EDGES ~41NCH, AS DIRECTED BY THE ENGINEER.
6. STEEL PIPE SHALL BE HOT DIP GALVANIZED IN
CONFORMANCE TO ASTM DESIGNATION A123. BOLTS. NUTS
AND WASHERS SHALL BE HOT-DIP GALVANIZED TO ASTM
DESIGNATION A15`3.
FOR CONTRACTORS INFORMATION ONLY
(TYPE 1)
APPROX. QUANTITI[S 20 FT. SECTION
CONCRETE CY 2.6
REINFORCING STEEL LBS .3.30
TOTAL BARRIER WT. LBS 11000
7. BOLTS SHALL CONFORM TO ASTM A.36. NUTS SHALL
CONFORM TO A.307 REQUIREMENTS AND SHALL BE TAPPED
OR CHASED AFTER GN_VANIZING. BOLTS AND NUTS
SHALL HAVE CLASS 2A AND 2B FIT TOLERANCES.
B. THE BARRIER SHOULD BE LIGHT IN COLOR AND SHOULD BE
SUPPLEMENTED BY DELINEATION AS DETAILED ELSEWHERE
iN THE PLANS.
TEXAS OEPARTMENT OF TRANSPORTATION
LOW PROFILE
CONCRETE BARRIER
(PORTABLE AND PRECAST)
j~ T.I'TT _~LF ! LL!;ZLF
Configurations of welded~ fabric other than as shown in the WWF Detail
will be permitted when the conditions tabulated below are satisfied,
DESCRIPTION LONGITUDINAL WIRES VERTICAL WIRES
1. Wire type Deformed Smooth or Deformed
2. Minimum (cumulative 0.1.35 sq. in. per longitudinal
total) wire oreo 1.24 sq. inch foot (req'd only in end
.3'-4 "of precost sections)
5. No. of wires
Minimum 6 4 at 12 "C-C ea. precost end
Maximum 14 12 at 4 "C-C ea. precast end
Minimum radius t~o
4. Bending radius n/a
vertical wire dlometers
5, Wire placement
o. Top wire Not tess than 4 nor more
than 5 vertical wire dia.
from the upper bends in n/a
the vertlcolwires
b. Bottom wire 4" ( +_ ~/~"
from bottom of barrier n/o
c. Other wires Uniformly and symmetrically Minimum spoclng 4
spaced along faces of barrier Maximum spacing 12
6. Maximum wire The smaller wire shall have an area
size differential of 40 9'0 or more of the larger wire.
End of
barrier
30'-0 "usual
11~4" 7"
7" ~ i 11~4" · I I~ typical ' ]~ ' I '
S bors
S bars
ELEVATION OF BARRIER
Additionalverticolsteelshallbe provided os necessary
to properly position steelond stabilize rebor cage.
/ t~ / S bors
~.. 1~/4 clear
\ ~ sides &
/ p (typ )
SECTION NEAR
ENO or BmRI~R
l'-g
BARS S
(#)
(GFode 300)
OETNLS OF REBAR OPTION
Min four
vertical ....
wire D .~ Verticolwelded wires
MD or MW 90, approx.
length 6.5 q',our at
12 "required at each
[qually ~ end of precost concrete
spaced
traffic borders.
I/~,,
~1 I/2" max Longitudinal
........... wires ten MD 80
END VIEW
Note : DetoU shown is for MD80 longitudinal
wires and MD or MW 90 vertical wires.
Other size and spoclng comblnotlons
meeting the tabulated conditions
may be used.
. ",.~ Ver tlcol steel member
nearest end of barrier
2" may be welded wire
rr~ n or tied bar.
Sufficient welded wire or auxiliary tied
bar shall be placed vertically at locations
as necessary to provide for cage stability.
M~nlmolly age oddltlonal vertical steel
reinforcement shall be located at the
mldpo[nt ( t )+.-of" the barrier.
ELEVATION VIEW
DETAILS OF WELOEO WIRE FABRIC OPTION
2"
End of
barrier
'~'-...~ V bors
I/2" rain 1.4 -.
w, max
VERTICAL WIRE DETAILS
OETNL OF BARRIER SHN3E
x When 1 'ACP is not used for
lateral support these dimensions
shall be adjusted accordingly.
- 1 "ACP or equlvolent
lateral support at
permanent barrier
locations
GENERAL NOTES
1. Where used r~bar reinforcement shall
conform to ASTM A-615 (Grade 500).
2. Barrier length sholl be ..tO ft. unless +-
otherwise specified in plans.
~1 concrete reinforcement joint ,
connection systems g~out and, etc.
as shown are considered as part of
the barrier for payment.
R : Radi us
D = Dameter
Approximate P.L.F. quantities
Concrete CY, 0.112
Rebar LB. 6.62
Welded wire
fobrlc LB. 4.82
~ For Contractor's information only
Weight of one 50 ft. unit Appro-~imotely 7 Tons
Texas Department of Trons~rtatlon
Design D/vis/on tRoadway)
PRECAST CONCRETE
TRAFFIC BARRIER
TYPE 2
PCTB(2)-96
FILE
~_'
i