Cơ sở tính toán các thông số cơ bản của máy rung hạ cọc cừ

ca sd TiNH TOAN CAC THONG S6 CO BAN CUA MAY RUNG HA COC CLf PGS.TS Tran Van Tuan ThS Nguyin Van Tinh Khoa Co Xay dt/ng Trudng Dai hgc XSy dung Tom tat BSi bSo dua m md hinh ca hgc, phuang trinh vi phSn vS Idi giSi cho vipc coc cu bing mSy mng Hudng din dch tinh chgn mdt sd thdng sd chinh cda mSy mng cgc cu DSc biet IS tinh cimg cda Id xo - chi tidt dd hdng cin thay thi tmng quS trinh su dung Summary: Ttie paper pmsents a mechanical model, drftemntial equations and nsso/uf/o/JS for piling by vibmtory machines This paper also pmsents instmctions on how to select a number of pammeters of the vibmtory piling machine and, especially, calculate the hardness of spring which is usually damaged during its use and needs to be mplaced Oat vdn de Md hinh co hpc md la qud trinh cpc vin cdn chua di den thda mdn su phu hprp giira thue tiin vd ly thuyet [3] Bdi bdo ndy trinh bdy ca sd tinh todn cdc thdng sd ca ban cda mdy rung cpc cir; dde bipt trinh bdy phuang phdp xdc djnh gid tri dd cd'ng cua d c Id xo liPn ket ddi vdi loai mdy rung cd liPn k i t mlm vdi d i u cpc MP hinh c a hoc coc CUP Mpt cae md hinh dpng lue hpe dan gian, mp ta khd day dd d c dpc thu cda qud trinh hg cpc bing rung dpng dupc trinh bdy d hinh Coi epc (1) Id tuyet ddi cd'ng vd bj kep chpt bdi gudc ma sat (2) vd gude dupc gdn vdi Id xo (3); giira cpc vd gudc ma sdt d lire ma sdt khP tde dung, gid tri tuypt ddi cda luc ma sdt dd bdng O^ luc ndy nhim md hinh hod lire d n bPn d a thdn cpc; luc d n d i u coc duoc mP hinh hda bdng Id xo (4) vd phao Hinh a) Md hinh ddng luc cgc bSng mng (5), giOa phao vd ndn d l t tdn tai lire ma sPt d ddng; b) Sad6 djch chuyin eua cgc dudi tSc gid tri tuypt ddi bing O' Hinh l b nhin Id IrPn dung cua It/c kich mng dtiu hoS F(t) 20 TAP CHf KHOA HOC CONG N G H XAY DUNG Sd06- 12/2009 xudng Id sa dd phd cda djeh ehuyin cpc dudi tac dung lue kich rung dieu hod F(t); dd thj d giQ'a bilu diln su phu thupc giu'a luc d n Q° vd djch chuyen eua cpc (x); dd thj d cudi bieu diln su phy thudc giQ'a luc d n Ql vd dich chuyen cua cpc (x) Ld xo chi chju ndn, cho nPn trPn cdc dd thj chi d djch ehuyen cua cpc d'ng vdi khoang thdi gian t,-t2 vd XyU md lue d n d mui bdng MP hinh trdn, dd r l t dan gian song vipc giai nd lai rat phice tap; mdt khde vipc giai gdp khd khdn cdn tinh chit khdng ddng nhit cda nen dat Theo [3], de giai bdi todn xdc djnh d c thdng sd ea ban cda mdy rung cd the sd' dyng phirang phdp tuyen tinh hda phuang trinh vi phdn ehuyin dpng cda may cung cpc vd dp dyng gia thuyet eong suit Idn nhat hp epc Phuvrng trinh vi phan vd Id'i gldl Td' phuang phdp tuyen tinh hod phuang trinh vi phdn ehuyen ddng cda mdy eung epc, theo [3] cd t h i vilt: nix-i-bx-i-cx = mor(»^cos(Bt = F3COscot dd: x Id tpa dp eua epe so vdi vj tri edn bing ddng cpc; m Id khdi lucng dao dpng cda cpc vd cdc phin Id dao dpng kPm theo; t IP thdi gian; b Id giam chin quy ddi cua dat vd ca hp mdy - cpc; e Id dp cirng quy ddi eua dat vd hp mdy - cpc duae xde djnh nhd g i i thuyet cdng suit Idn nhit hg cpc; co Id t i n sd gde eua lye gPy rung; m^r Id mo men qudn tinh ITnh gdy rung Nghipm cua phuang trinh vi phdn (1) nhu sau: X = XjCOsCco t - i p ) X = -coXjSin((nt-(p) ,„, 2hco , , (p = arctg —z 5-; b = 2hm ; dP: co„ - c o F, cos (3) ; «„ = /— Id tan sd dao ddng riPng eua hp mdy - epe sin cp = J(coJ-co^)'+4hV ^'" Cdng d n thilt de tri dao ddng mpt chu ky dupc xdc djnh nhu sau: A= J F(t)xdt =-FJXJCO J cos CO t.sin(co t-cp)dt 0 A = 7iF,XjSin(p (4) Cdng suit trung binh ddng ca eung d p cho he rung dupe tinh nhu sau: N,b= —= A ; ^ = - F x , cosincp I dd: T = — itt (5) I Id ehu ky dao dpng Thay x Id' d n g Ihipc (3) vdo bieu thu'c (5) ta cd: CO TAP CHf KHOA HOC C O N G NGHE XAY DUNG Sd06 -12/2009 21 ^j^_ F.cDsin2(p 4m(coJ-CB^) (6) Xet bieu thu'c (6) vd phai dat eye tri neu: sin2cp = l hode: cOo >co sin 2cp = - cOo < co (7) (8) Trudng hpp (7) xay

Hinh Dd thj cda hSm C2 = f(n) NhSn xit: Tdc dp quay cda dpng ca edng Idn thi dp cd'ng cua Id xo d n g Idn Do dd khPng nPn chpn n qud Idn 26 TAP CHf KHOA HOC C O N G N G H XAY DUNG sd06 -12/2009 1.8>10 : c2(N/m) 1.6>10 1.4>10 1.2>10 L>i.O S>10 6>i0 rn2(kg) 4>10 200 400 £00 800 1000 Hinh Dp thj eda hSm Cz = ftm^) NhPn xit: C2 g i n nhu ty ip thupn vdi m2 dd khdng nPn tdng mjquP ldn K i t luan Bdi bdo dd dua md hinh ea hpc, phyang trinh vi phdn vd ldi giai eho viPe hg epe cd" bdng mdy rung Hudng d i n edeh finh chpn mpt sd thPng sd ehinh eua mdy rung hg cpc ed' Ope bipt Id tinh dp cd'ng cua Id xo - ehi lilt de hdng d n thay the qud trinh sd- dung Bdi bdo Id tdi lipu tham khao rlt bd Ich cho vipe khai thdc, su- dyng, Hnh todn, thilt k l vd e h l tgo mdy rung hg cpc cd Tdi li^u tham khdo Trin Vdn Tuin, Luu Od-c Thgch, Phan Vdn Thio Ca sd ly thuyit tinh toSn cdng suit cho cSc ea ciu gSy rung Tuyin tPp cdng trinh khoa hpc Sd 2-1995, trang 230 -238 Trin Vdn Tuin Ca sd ky thuSt rung xSy dung vS sSn xuit vpt li$u xSy di/ng Nhd xult ban Xdy dyng - 2005 BaywaH B A., 1/1.H BbixoBCKnii Bu6pau,uoHHbie uaiuuHbi u npou,eccbi a empoumenbcmee MocKBa, 1977 M.M CwopoflMHOBa Cneu,uanbHbie uawuHbi u ododypoeanusi dnn ycmpoucmea ocHoeanuu (pynbdai^eHmoe MoeKBa,1972 TAP CHf KHOA HOC C O N G N G H E X A Y DUNG Sd06-12/2009 27 ... vd khdi lupng mdy rung (m = mc-*- mmr) + Tilp den tinh todn theo cdc cdng thdc sau: - Md men qudn tinh tinh : - T i n sd rung: mor = l,06mx3 j.,.,j x, =coXj (12) - Cdng suit rung tinh chpn sa... J F(t)xdt =-FJXJCO J cos CO t.sin(co t-cp)dt 0 A = 7iF,XjSin(p (4) Cdng suit trung binh ddng ca eung d p cho he rung dupe tinh nhu sau: N,b= —= A ; ^ = - F x , cosincp I dd: T = — itt (5) I... Tinh chpn cdc thdng sd chinh cua may rung h? cpc Tu- ly thuyet vd qua thyc nghipm, tdc g i i [3] dd de xult cdch tinh ehpn sa bp ede thPng so chinh cua mdy rung hg epc nhu sau: -" Trudc hit ehpn