y v ' y v '
KHAO SAT VAOE XUAT GIAI PHAP HAN CHE YEU TO LANG PHI TRONG GIAI OOAN THI CONG
CHUNG CU" CAO TANG TAI TP.HCM
Pham Hong Luan H^ Duy Khanh
ABSTRACT
There are so many non-value adding activities, also known as waste, in construction practices and many among ttiem were unnoticed or unattended.
Previous studies have shown that there were a significant amounts of values loss due to waste in construction process and productivity improvement can be achieved by reducing or eliminating the waste and / or improved making process. This paper was conducted on the basis of research concepts of waste and waste levels construction practices in HoChiMinh city based on the principles of Lean Construction. A quantitative survey was conducted through questionnaires, which is moderated by experts and experienced people, by a group of subjects were randomly selectetJ, including individuals with functional management, consulting or supervision of construction activities in high-rise apartment building.
Eventually, it will propose some solutions to reduce the waste elements after defined the mainly cause of wastes.
TS. Pham Hong Luan Khoa ky thuat Xay dimg
Trudng Dai hoc Bach Khoa - DHQG TPHCM
Th.S Ha Duy Khanh Khoa Ky thuat Xay dung
TriTomg Dai hoc Bach Khoa - DHQG TPHCM
I . G i d i thieu
Xay dQng nganh la tao dQng o sd vat chat eho cac nganh Kien true - ky thuat khac, d d n g gdp vao viee giai quyet viec lam trong xa hdi va tdng thu nhap cua dat nQdc. Tuy nhien, ngay nay, nganh xay dQng van edn dang dUPng dau vdi nhieu khd khan nhQ nang suat lao ddng thap, thieu an toan lao ddng, dieu kien lam viec kem va t h u d n g khdng dat chat iQpng (Koskela, 1993)[4]. Hon nQa, trong thdi ky hdi nhap va canh tranh, yeu eau cai thien chat lupng san pham ludn la mdt thach thUe ddi vdi nganh xay dUng.
Van de lang phi, hay cdn gpi la eac hoat ddng khdng mang lai gia tri gia tang, tU lau duac xem la thach thQc Idn, vl the, nhieu nghien cQu dQpe thure hien de xac dinh nguyen nhan gay ra lang phi bang viee dua ra nhQng ky thuat hay nhQng cdng eu mdi vdi muc dich cai tien quy trinh, tQ d d nang cao nang suat lao ddng. NhQng ky thuat nay dQa tren nhQng triet ly va y t u d n g eua san xuat tinh gpn trong Toyota Production System TPS (Taichi Ohno,1980). Tuy nhien, giua quy trinh san xuat eua Toyota va quy trinh xay dung cd nhQng diem khac nhau, do d d m u d n ap d u n g dUpc nhQng nguyen ly eua TPS can phai hieu rd nhQng dae thu cua xay dQng, tU d d hinh thanh nen y tUdng tinh gpn trong xay dij'ng: Lean Construction - LC
Nhieu nghien cUu tren the gidi chQng td rang mdt sd iQpng dang kegia tri cua dUan bi that thoat do viec quan ly kem, thiet ke sai sdt, thi edng khdng dat chat lupng, thdi gian keo dai, thieu hijt vat tu... Chinh nhQng dieu nay tao ra sU lang phi eho lupng tien ma chung ta thuc chat phai ehi tra de hoan thanh dur an n h u ke hoach. Hpn nQa, LC dupe nhin nhan n h u la mdt eo hdi de giai quyet nhung van de lang phi hien tai cua nganh cdng nghiep xay dung va Ude lupng sU tae d d n g eua lang phi den tdng the dUan.
Bai bao nay tap t r u n g nghien cQu viec xac nhan va d i i doan hien trang nang suat lao d d n g eac duf an chung cQ cao tang tai TP.HCM vdi nhQng mue tieu: (1) Khao sat sQ hieu biet chung eua nganh xay dQng dTPHCM vdi cac yeu t d lang phi, (2) Xac dinh cac nguyen nhan gay ra lang phi va phan loai lang phi dQdi khai niem LC, (3) Xac dinh mQe dp anh hudng cua eae yeu t d lang phi dudi eae gdc dp ehi phi va tien dp, (4) Tim hieu kha nang cai tien nang suat lao d d n g bang viee han che hoac loai tru/
yeu t d lang phi dudi eac khai niem eua LC.
2. Khai niem va cac nguyen ly cua san xua't tinh gpn
Viec tinh gpn trong san xuat thudng la giam khdng gian, nhan lUe, thiet bi va thdi gian; san xuat lap ghep; module hda eau kien;
Ung d u n g vi t i n h ; cdng nghiep hda v a t u d d n g hda... —• d d la nhQng cai tien trong cae khau, cac quy trinh duac tien hanh mdt each ddng t h d i trong san xuat —• hinh thanh nen mot p h u a n g thUe san xuat mdi - phUPng thQc"san xuat tinh gpn". Xu the phat trien nay tap trung vao n h u n g ly thuyet eo ban lien quan den quan ly san xuat va chien lupe cai tien cho quy trinh, bdi viee han che/ loai trU nhQng lang phi t d n tai. Alaredn (1995)[6] ngoai viec chi ra eO hdi cai tien sQ thQc hien cd the tap trung vao chien iQpe giam thieu/han che lang phi phai song song vdi chien iQpc cai thien gia tri gia tang eua san p h a m .
Bieu cdt Idi cua triet ly san xuat tinh gpn la SQ ket hap giQa nguyen ly va quy trinh eho hai hoat d d n g chinh: chuyen ddi va ludng cdng viec. Hoat d d n g chuyen doi la nhQng hoat d d n g true tiep tae d d n g vao nguyen-vat lieu de tao ra gia tri eho san pham cudi eung.
Hoat d d n g ve luong la nhQng hoat ddng dau vao cho hoat d d n g chuyen ddi bao g d m ludng t h d n g tin va ludng tai nguyen. D o d o , muc tieu cai tien nang suat lao d d n g bdi cac triet ly san
6 4 B^E^nilH^l 0 6 . 2 0 1 1
Bang 2. Md ta eae nguyen ly eua san xuat tinh gpn, Koskela 1992 Nguyen ly
l.Giam thieu ty trpng eua cae hoat ddng khdng dem lai gia tr| gia tang 2.Tang san iQpng dau ra bSng viec xem xet ky iQdng cac yeu eau eua khach hang 3. Giam sQ bien doi trong quy trinh
4, Giam thieu chu ky lam viee trong quy trinh
5, Don gian hda bang each giam thieu sd iQpng bQdc thQc hien va bd phan.
6, Nang cao dp linh hoat dau ra eua san pham 7, Nang cao tinh rd rang cua quy trinh
8, Tap trung sQ kiem soat vao ludng
9, Xay dung sQ cai tien lien tue vao quy trinh
10. Can bang sQ cai tien ve ludng vdi sQcai tien ve chuyen ddi.
11. Diem chuan
PhUcrng phap ap dung
- Han che phan chia cdng viee nhd hon.
- Quy trinh phai dQpc thiet ke mdt each ed trat t i i trudc khi thuc hien.
- Giam thieu nhQng xQ ly khdng can thiet.
-Thuc hien mdt thiet ke ludng edng vieeed he thdng, trong dd khach hang dQpe quy dinh eho tQng giai doan, va yeu cau cua hp dupe phan tich va xem xet ky ludng,
- Nang cao tinh minh bach va cai tien lien tue thdng qua nhu cau eua khach hang.
- SQ dung ly thuyet kiem soat t h o n g ke de tieu chuan hda cae hoat ddng thdng qua viec lay mau xac suat.
- Loai bd nhQng xQ ly khdng can thiet - Giam kich thudc me/ dctt, sd khau,
- Bd tri mat b j n g hop ly de khoang each di chuyen la nhd nhat -Thay doi hoat dcpng tUtuan tUsang song song
Cd lap eae hoat ddng gia tang chinh
- Rut ngan cac ludng bang cac hoat ddng hpp nhat
- Giam thieu eae phan cua san pham bang each thay ddi thiet ke - Md-dun hda va tieu ehuan hda eae bd phan
-Tach eac mdi lien ket mdt each hpp ly -Tdi thieu hda sd lupng thdng tin can thiet.
- Cue tieu hda kich ed eua eac phan de gan nhat vdi kieh cd yeu eau - Giam dp khd khi cai dat va chuyen giao
- Huan luyen ky nang da tay nghe.
-Tao ra quy trinh c d t h e quan sat dUOc bang viec bd tri thich hap va g j n cae bien bao cho quy trinh.
-The hien eae thudc tinh c d t h e nhin thay dupc thdng qua cac phep do.
- Cung cap day du cac thdng tin cua quy trinh trong khu vQc lam viec n h u e d n g cu, vat lieu, nhan sU.
- Quy trinh san xuat phai do ludng dupe va cd b<!) phan kiem soat chat iQpng cho san pham cudi cung.
-Tang eUdng sQ hop tae giQa eac k h a u / t d e h u c ma ludng di qua.
- Nhin nhan eae nguyen nhan gay ra sQ khdng hieu qua cua quy trinh va dQa ra eae giai phap.
- Gan trach nhiem cho cac ea nhan va td chQc vdi nhiem vu cai tien.
- SQdung cac tieu chuan cung nhQ cae giai phap tdi Qu hien tai.
-Tach thdi gian cai tien cho ludng ra khdi thdi gian cai tien cho hoat ddng chuyen ddi - Giam thieu eac yeu eau eua hoat ddng chuyen ddi,
- Ap dung cac edng nghe mdi.
- Danh gia diem manh va diem yeu eua quy trinh
- Nam bat kip thdi xu the cua thi tru'dng va cac quy dinh cua c o quan chQc nang - Ket hop va sQa ddi cac thdng le tdt nhat trong quy trinh san xuat d o n vi
Nguyen ly cua san xuat tinh gpn trong eai tien nang suat lao ddng
SUgl^m bot cua luong - Giam ty trong cua gia tri khdng gia tang.
-Giam subien ddi.
-Giam thdi gian ehu ky.
- Giam sd budc thuc hien hoac cac bd phan.
SUlinh hoat cua luong -Tang gia tri dau ra.
-Tang tinh linh hoat eua dau ra, - Tang tinh rd rang cua quy trinh.
- Oiem chuan.
SU on djnh cua luong -Tap trung vao quy trinh hoan thanh.
- Xay dung sU cai tien lien tuc trong quy trinh.
- Can bang eai tien ve ludng vdi cai tien ve chuyen ddi.
Hinh 1. Phan loai cac nguyen ly ciia san xuat tinh gon xuat tinh gpn can phai chia ra rd rang bang viec tap trung vao loai trU hoac giam thieu tQng loai lang phi tdn tai ben trong hoat ddng ludng.
3. Khai niem va phan loai lang phi 3.;. Khdi niem Idng phi
TrQdc day, lang phi hau nhQ chi dQpc biet den la lang phi ve vat lieu tren edng trudng cho tat ea eac hoat ddng thUc hien. Phan Idn nguyen nhan lang phi cd lien quan den Id hdng trong he thdng quan ly, do khdng quan tam nhieu den lang phi va do cac dU an khae nhau cd mQc
dd lang phi khae nhau tren cung mdt loai vat lieu... —> mdt iQpng dang ke cac lang phi tdn tai trong quy trinh xay dUng va nhieu trong sd chung khdng duoc biet den hoac an di, Ngay nay, trong triet ly san xuat mdi, lang phi trong xay dung dupc hieu la bat ky sQ khdng hieu qua nao khi sQ dung thiet bi, vat tU va nhan iQc cho cae hoat ddng san xuat hoac sQ dung mdt lupng vdn Idn han can thiet, Lang phi bao gdm cae thiet hai ve vat chat lien quan den chi phi va nang suat do khdng dem lai gia tri gia tang eho san pham dau ra, ^ triet ly xay dung tinh gon tach cae hoat ddng thanh dem lai gia tri gia tang va khdng dem lai gia tri gia tang, Han nua, triet ly san xuat mdi nay nhin nhan cac hoat ddng khdng dem lai gia tri gia tang la lang phi va dQa ra eae nguyen ly de han che nd, dae biet la tao ra ehi phi eo hdi bdi viec han che lang phi thdi gian va mat mat gia tri tdn tai trong md hinh thdng thurdng
3.2. Phan loai Idng phi
06.2011 ^Miiiias? 6 5
Tong chi phi
Quan diem san xuat truyen thong
Quan diem san xuat tinh gpn
•o
Cai tien quy trinh
Chi phi eua tat ea cac hoat ddng
Chi phi cua eac hoat d d n g khdng dem
lai gia tri gia tang Chi phi cua cae hoat
d d n g dem lai gia tri gia tang Hinh 2, So sanh quan diem lang phi gitta san xuat thong thudng vol san xuat tinh gon
Yeu to quan ly,' quan tri Yeu [6 con nguori
\'eu to (hire tiicn' (hue Ihi Yeu to vat tu
Yeu to giao tiep,' thong tin
00°-b
Hinh 4, Lien ket nguyen nhan vol yeu to lang phi
Bang 3, Phan loai yeu td lang phi trong xay diing
#
Q l 0 2 0 3 Q4 0 5 Q6 0 7 0 8 0 9
0 1 0 O i l 012 013 0 1 4 015 0 1 6
0 1 7 0 1 8 0 1 9
1 . Lang phi chuyen doi triic tiep
Phan bd d u hoac khdng can thiet cac thiet bi tren cdng trQdng.
Phan bd dQ hoac khdng can thiet eae vat lieu tren edng trudng.
Phan bo dU hoac khdng can thiet sd luong cdng nhan tren cdng trudng.
Thu tuc hoac giao thQc lam viec khdng can thiet.
Vat lieu bi mat mat hoac thieu hut tren cdng trudng.
Vat lieu bi h u hdng trong khoang thdi gian xay d i i n g . Xu ly sai hoac cac loi trong Ung dung xay dung.
Vat lieu cho cdng viee lam lai, sQa chUa.
Tai nan tren edng trUdng (bat kha khang).
2. Lang phi thdi gian khong phu them
Dai ngudi khae de hoan thanh edng viec (thdi gian nhan rdi), Oai thiet bi sc; dupe phan phat tren cdng trudng.
Dpi vat lieu se duac phan phat tren cdng trudng, Chd dpi edng nhan lanh nghe tren edng trudng, Opi phan loai va xac nhan bdi khach hang va nha tU van, Thdi gian do cdng viee lam lai, sua chua hoac bd di, Thdi gian eho edng nhan nghi ngpi.
3. Lang phi thdi gian phu them
Thdi gian de giam sat va kiem tra eae cdng tac trong xay dung.
Thdi gian eho viec hu'dng dan va giao tiep giua cac ea nhan.
Thdi gian cho viec van chuyen cdng nhan, thiet bi va vat lieu.
Viee phan loai lang phi dUdi cae khai niem eua LC la theo gia tri cuia san pham dau ra nhu Bang 3 va cac nguyen nhan gay ra lang phi nhu Bang 4:
4. Thu thap va phan tich so lieu Odi t u p n g cua nghien cUu nay la eac nhan vien cd kinh nghiem triic tiep quan ly va thi edng xay d i i n g . Bang cau hdi dupc phan phat dam bao t i n h khach quan, t i n h dai dien va tinh day du de dam bao ket qua cd sU chech thap nhat. PhUdng phap lay mau phi xac suat se dupe ap duing t r o n g nghien eUu nay do nhQng gidi han nhat dinh cua nghien cUu.Cacvitrilay mau trong pham vi tai TPHCM d cac cdng trinh dupe thue hien bdi eac cdng ty xay dung tuong ddi cd tieng tren thQong trQdng. Sd iQpng nnau t h u lai la 185 bang, sd iQong mau sau khi Ipc la 128 bang, dat t y l e 8 1 % .
4.1. Ket qua phan tich thong ke mo ta a. Lang phi chuyen doi trUc tiep
Su cdng nhan la lang phi: 0 1 nhieu nhat vdi 88.1 % va 0 6 it nhat vdi 74.3%.
Kha nang kiem soat lang phi: 0 8 nhieu nhat vdi 9 1 . 1 % va Q6 it nhat vdi 83.6%.
Mdi lien he giQa edng nhan va kha nang kiem soat lang phi
Lang phi Khdng lang phi
Kiem soat d u p c 0.529 0.227
Khdng kiem soat dupc
0.166 0.078 fa. Lang phi thdi gian khong phu them Su edng nhan la lang phi: 0 1 2 nhieu nhat vdi 89.2% va 0 1 4 it nhat vdi 62.7%.
Kha nang kiem soat lang phi: 010 nhieu nhat vdi 92.9% va 0 1 3 it nhat vdi 80.9%.
Mdi lien he giQa edng nhan va kha nang kiem soat lang phi
Lang phi Khdng lang phi
K i e m soat dupc 0.555 0.224
Khdng kiem soat dupe
0.146 0.075 c. Lang phi thai gian phu them
Su edng nhan la lang phi: Q l 7 nhieu nhat vdi 67.6% va Q18 it nhat vdi 57.3%.
Kha nang kiem soat lang phi: 019 nhieu nhat vdi 86.2% va Q l 7 it nhat vdi 76.9%.
Mdi lien he giQa cdng nhan va kha nang kiem soat lang phi
Lang phi Khdng lang phi
K i e m soat dQOc 0.310 0.365
Khdng kiem soat dQoe
0.151 0.174 a r^' " I
4.2. Ket qua phan tich thong ke suy luan I. Moi tuang quan giCta cong nhan, kiem a. Moi
6 6 ^E^nini^v 06.2011
Bang 4. Phan loai nguyen nhan lang phi trong xay dQng A. Yeu to quan ly/ quan trj
A l . SQ hpp tac yeu kem giQa cac ddi tQpng d i i an.
A2. Tien dp va ke hoach cdng viec yeu kem.
A3.Thieu kiem soat/quan ly.
A4. Benh quan lieu.
B. Yeu to con ngUcti
Bl.Thieu ky nang/trinh dp nganh nghe.
82. Thieu kinh nghiem thuic te.
83. Qua it ngQdi giam sat/doe cdng.
B4. Giam sat/kiem tra qua mudn.
85. Phan bo edng nhan, thiet bi, vat t u qua kem.
C. Yeu to thirc hien/ thUc thi
CI. Phuang phap xay dung khdng phu hpp.
C2.Thiet bi loi thdi/qua cu.
C3. Thieu hut thiet bi, edng nhan, vat t u can thiet.
C4. Su Ilia chpn thiet bi han hep hoac thiet bi khdng hieu qua.
C5. Mat bang bd tri cdng trQdng yeu kem/khdng phu hpp.
C6. Tai lieu/hd sP cung cap eho edng trQdng cham/khdng du.
D. Yeu t o vat t u
D l . Phan phdi vat tQ cham t r i . 02. Chat iQpng vat tQ kem.
03. Vat tQ khdng dung vdi nhu eau cuia cdng trQdng.
D4. Tdn trQ vat tQ yeu kem.
05. XQ ly/gia cdng vat lieu kem tai cdng trQdng.
E. Yeu to thong t i n / giao tiep E l . Thdng tin cho cdng viee bi Idi hoac sai.
E2. Thdng tin den cham hoac dQa ra quyet dinh thiic hien cdng viec qua lau.
E3. Thdng tin khdng rd rang.
Bang 5. Ket qua phan tich lang phi chuyen ddi true tiep
Cdng nhan
Kiem soat
Tan suat
Pearson Correlation Sig. (2-tailed) N
Pearson Correlation Sig. (2-tailed) N
Pearson Correlation Sig. (2-tailed) N
Cdng nhan 1 128 -0.056 0.529 128 -0.108 0.225 128
Kiem soat -0.056
0.529 128 1 128 -0.084 0.344 128
Tan suat -0.108
0.225 128 -0.084 0.344 128 1 128 Being 6. Ket qua phan tich lang phi thdi gian khdng phu them
Cdng nhan
Kiem soat
Tan suat
Pearson Correlation Sig. (2-tailed) N
Pearson Correlation Sig. (2-tailed) N
Pearson Correlation Sig. (2-tailed) N
Cdng nhan 1 128 -0.041 0.649 128 0,053 0,553 128
Kiem soat -0,041
0,649 128 1 128 -0,084 0,344 128
Tan suat 0,053 0,553 128 -0,127 0,153 128 1 128 Bang 7. Ket qua phan tich lang phi thdi gian phu them
Cong nhan
Kiem soat
Tan suat
Pearson Correlation Sig. (2-tailed) N
Pearson Correlation Sig. (2-tailed) N
Pearson Correlation Sig. (2-tailed) N
Cdng nhan 1
128 -0.073 0 . 4 1 0 128 (-0.236) 0.007 128
K i e m s o a t -0.073
0 . 4 1 0 128 1
128 - 0 . 1 0 2 0.253 128
T a n s u a t (-0.236)
0.007 128 -0.102 0.253 128 1
128
sodr \id tan sudt xay ra cua lang phi
SQ dung phan tich Pearson-r, vdi C=95%, ket qua tUSPSS n h u Bang 5, Bang 6 va Bang 7:
TQ ket qua phan tich, chi cd duy nhat mdt trQdng hop la cd mdi lien quan vdi nhau giUa sQ cdng nhan va tan suat xay ra cua lang phi thdi gian phu them, do K = 0.007 < 0.01
b. Xep hang cac yeu to lang phi theo tan sudt xay ra
SQdung thang do 5-seale: 1 -ChQa bao gid, 2-Rat hiem khi, 3-lt khi, 4-ThQdng xuyen, 5-Rat thQdng xuyen.
Phan tich bang kiem dinh t-mdt phan vdi khoang tin cay 9 5 % .
c. Xep hang cac nguyen nhan Idng phi theo mile do tdc dong
SQdung thang do 4-seale: 1 -Rat it, 2-Hai it, 3-Hai nhieu, 4-Rat nhieu.
Phan tich bang kiem dinh t-mdt phan (oneway t-test) vdi khoang tin cay 9 5 % .
d. Lien ket nguyen nhdn vdiyeu to Idng phi Muc dich cua phan tich nay la ket ndi nhQng yeu td lang phi vdi nguyen nhan gay ra nd theo kinh nghiem cua ngQdi tra Idi. Ket qua dQpc the hien nhQ Hinh 4 ben dQdi:
5. Ket luan va kien nghj
5.7. Mot so ket ludn tU ket qua phan tich so lieu
Siicdng nhan ve lang phi thi kha thap: lang phi thdi gian phu them 46.3%, tiep den lang phi chuyen ddi triie tiep 70.5% va lang phi thdi gian khdng phu them 78.6% —• cac ea nhan van chQa hoan toan hieu dQpc het cae khai niem ve ludng va eac hoat ddng khdng dem lai gia tri Qia tang va ed xu hQdng xem chung la nhQng edng viec phu them can thiet cho hoat ddng chuyen doi.
DQa tren Bang 8, cae yeu t d lang phi eua hoat ddng chuyen doi triic tiep (05,06) la xay ra nhieu nhat |i = 3.328, tiep theo la lang phi thdi gian phu them (Q18) vdi p = 3.313 va lang phi thdi gian khdng phu them (Q12) vdi p = 3.250
—> eae lang phi ve ludng d mdt mQe dp thap va do dd, quy trinh "trdi chay" kha tdt nhQng yeu to lang phi tac ddng nhieu nhat lai la hoat ddng chuyen ddi triic tiep nen nang suat cua tdng the d u an bi anh hQdng dang ke.
Diia vao Bang 9, nhdm yeu t d ve quan ly/
quan tri (A2, A3, A4) la tae ddng manh nhat vdi p = 2.711 va nhdm yeu td ve giao tiep va thdng tin (El, E3) la it tae ddng nhat vdi \i = 2.383. Hon nQa, dua vao Hinh 4, yeu td ve quan ly/ quan tri dupe cdng nhan la nguyen nhan ehi phdi eho tat ca eac trudng hop (10/19) -^ de giam thieu hoac loai bd yeu td lang phi va eai thien nang suat cua quy trinh xay diing can tap trung nhieu nhat vao each thQc quan ly/ quan tri.
Chi cd mdt trudng hpp la cd mdi tuong quan nghich chieu nhau (r=-0.236) giQa edng nhan va tan xuat xay ra eua lang phi thdi gian khdng phu them, tham chi la ty le cdng nhan
06.2011 ^Klil'TiatT 6 7
Bang 8. Xep hang eac yeu t d lang phi theo tan suat xay ra
#
1 2 3 4
18 19
Bien 0 5 0 6 Q18 0 1 2
0 1 6 0 9
N 128 128 128 128
128 128
M e a n 3.328 3.320 3.313 3.250
2.875 2.820
SD 0.906 0.896 0.876 0.988
1.004 0.909
SEM 0.080 0.079 0.077 0.087
0.089 0.080
Loai lang p h i Chuyen d o i trQc tiep Chuyen ddi true tiep Thdi gian p h u t h e m Thdi gian k h d n g p h u t h e m
Thdi gian k h d n g phu t h e m Chuyen ddi true tiep Bang 9. Xep hang cae nguyen nhan lang p h i t h e o mQe d p tac d d n g
#
1 2 3 4 5
22 23
Bien A3 A2 A4 B4 B5
E3 El
N 128 128 128 128 128
128 128
IVIean 2.711 2.695 2.688 2.688 2.664
2.383 2.367
SD 0.862 0.740 0.847 0.801 0.806
0.861 0.886
SEM 0.076 0.065 0.075 0.071 0.071
0.076 0.078
Loai nguyen nhan Quan ly Quan ly Quan ly Con n g u d i Con ngUdi
Giao t i e p / t h d n g t i n Giao t i e p / t h d n g t i n
va kha nang kiem soat lang p h i rat cao - • cac yeu t d lang p h i hoac tan suat xay ra lang phi khi thuc hien d i i a n ed t h e dUpc cdng nhan cao bdi cae d d i t u a n g khao sat n h u n g khdng bat bupc phai kiem soat duac c h u n g va ngupc lai
5.2. Mot so gidi phap de xuat de han che yeu to Idng phi
Oiia vao cac ket qua phan tich, eac yeu to lang p h i khi t h i i c hien cae d i i an chung cQ cao tang ed t h e dQdc han che hoac loai bd theo m d t sd giai phap kien nghi nhQ sau:
Giai phap 1:
Tac dong vao nhom yeu to c o n ngu-di
Giai phap 2:
T a c dong vao nhom quan l y / q u a n trj
Ly do
- DQa vao Hinh 4, yeu t d con ngQdi la nguyen nhan chinh gay ra cho hau het cac yeu t d lang phi, chiem 10/19 yeu t d . - Han nQa, dua vao Bang 9, yeu t d eon ngudi lai ed tae d d n g xep thQ hai den nang suat xay d u n g
- Oua vao Hinh 4, yeu t d quan ly/ quan tri la nguyen nhan chinh gay ra xep thQ hai cho cae yeu t d lang phi, chiem 6/19 yeu t d . - Hpn nQa, dQa vao Bang 9, yeu t d quan ly/ quan tri lai ed tac d d n g xep thQ nhat den nang suat xay dQng
Noi d u n g
- Nang cao t r i n h d p chuyen m d n cua cac can b p quan ly va ky thuat khi thQc hien d i i a n .
- Oao tao ky nang da tay nghe (Multi-skilled) eho edng nhan va nhan vien de dap Qng t d t yeu eau eua edng viec khi can thay d o i .
- Phan b d edng nhan kip t h d i va day duj de edng viec k h d n g bi gian doan.
- T a n g cudng s U p h d i h o p giQa can b d ky t h u a t va ddc edng de cdng viec dupc trien khai t d t n h a t . . .
- Nang cao t r i n h d p chuyen m d n eua cac can b p khi thue hien d u a n , dac biet la kha nang quan ly d i i a n .
- Chuan bi t d t ke hoach vat tQ, nhan edng va t h i e t bi trQdc va trong khi t h i i c hien d i i a n .
- Lap tien d p va ed ke hoach t h i i c hien rd rang, d a m bao ngan sach.
- Phdi h p p va t h d n g t i n kip t h d i d e n eac b d phan khac...
TAI LIEU THAM KHAO
1, Adrian, James.),, "Construction Productivity Improvement."
Elsevier Science Publishing, NewYork,pp 45-51,1987, 2, Koskela, Lauri, "Application of New Production Philosophy to Construction"Tech, l^ep. No 72, CIFE, Stanford, California, 1992, 3, Alarcon, Luis, F„ (1993), "Modeling Waste and Performance in Construction," Proceedings of the 1st Conference of the International Group for Lean Construction, Alatcbn (ed,), A,A, Balkema, Rotterdam, The Netherlands, 1997,
4, Koskela, Lauh (1993),"Lean production in construction,"
Proceedings of the 1 st Conference of the International Group for Lean Construction, Alarcon (ed,), A,A, Balkema, Rotterdam, The Netherlands, 1997,
5, Alarcon, Luis, F„ (1994), "Tools for The Identification and Reduction of Waste in Construction Projects" Proceedings ofthe 1st Conference ofthe International Group for Lean Construction, Alarcon (ed,), A,A, Balkema, Rotterdam, The Netherlands, 1997, 6, Alarcon, Luis, F„ (1995), "Training field Personnel to Identify Waste and Improvement Opportunities in Construction,"
Proceedings of the 1 st Conference of the International Group for Lean Construction, Alarcon (ed,), A,A, Balkema, Rotterdam, The Netherlands, 1997,
7, Serpen, Alfredo, Venturi, Adriano & Contreras, Jeanette, (1995),
"Characterization of waste in building construction projects," In Lean Construction, Alarcon (ed,). A,A, Balkema, Rotterdam, The Netherlands, 1997,
8, Formoso, C,T, Issato, E,L, Hirota E,H, "Method for Waste Control in the Building lndustry,"Proceedings ofthe 7th Conference ofthe International Group for Lean Construction, Berkeley, California, USA, July, 1999,
9, Formoso, Carlos e t afMaterial Waste in Building Industry: Main Causes and Prevention," In Journal of Construction Engineering and Management, July/August, pp, 316-318,2002, 10, Wright, Gordon, Love,"Lean Construction Boosts Produrtivity,"
In Building Design & Construction, 41(12), pp,29-32,2000, 11, Koskela L,, Lauri, "An Exploration toward a Production Theory and Its Application to Construction" Proceedings of the 7tli Conference of the International Group for Lean Construction, Canada, 2000,
