<PAGE>
===============================================================================
+----------+
| FORM 4/A | U.S. SECURITIES AND EXCHANGE COMMISSION
+----------+ WASHINGTON, D.C. 20549
[_] Check this box if
no longer subject STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP
to Section 16.
Form 4 or Form 5 Filed pursuant to Section 16(a) of the Securities
obligations may Exchange Act of 1934, Section 17(a) of the
continue. See Public Utility Holding Company Act of 1935 or
Instruction 1(b). Section 30(f) of the Investment Company Act of 1940
(Print or Type Responses)
- --------------------------------------------------------------------------------
1. Name and Address of Reporting Person*
FOSTER VINCENT D.
- --------------------------------------------------------------------------------
(Last) (First) (Middle)
1300 POST OAK BLVD, SUITE 1220
- --------------------------------------------------------------------------------
(Street)
HOUSTON TX 77056
- --------------------------------------------------------------------------------
(City) (State) (Zip)
2. Issuer Name and Ticker or Trading Symbol U.S. CONCRETE, INC. (RMIX)
-----------------------------------
3. IRS or Identification Number of Reporting Person if an entity
(Voluntary)
--------------
4. Statement for Month/Year DECEMBER 1999
---------------------------------------------------
5. If Amendment, Date of Original (Month/Year) JANUARY 3, 2000
---------------------------------
6. Relationship of Reporting Person(s) to Issuer (Check all applicable)
[X] Director [ ] Officer [ ] 10% Owner [ ] Other
(give title below) (specify below)
----------------------------------------------------------------
7. Individual or Joint/Group Filing (Check Applicable Line)
_X__ Form filed by One Reporting Person
____ Form filed by More than One Reporting Person
TABLE I--NON-DERIVATIVE SECURITIES ACQUIRED, DISPOSED OF, OR BENEFICIALLY OWNED
<TABLE>
<CAPTION>
- ------------------------------------------------------------------------------------------------------------------------------------
1. Title 2. Trans- 3. Trans- 4. Securities Acquired (A) 5. Amount of 6. Owner- 7. Nature
of action action or Disposed of (D) Securities ship of In-
Security Date Code (Instr. 3, 4 and 5) Beneficially Form: direct
(Instr. 3) (Month/ (Instr. 8) Owned at Direct Bene-
Day/ ----------------------------------------------- End of (D) or ficial
Year) Month Indirect Owner-
Code V Amount (A) or Price (Instr. 3 and 4) (I) ship
(D) (Instr. 4) (Instr. 4)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C>
Common Stock 12/29/99 P 1,000 A $6.25 D
- ------------------------------------------------------------------------------------------------------------------------------------
Common Stock 12/30/99 P 2,000 A $6.1875 D
- ------------------------------------------------------------------------------------------------------------------------------------
Common Stock 363,790 D
- ------------------------------------------------------------------------------------------------------------------------------------
Common Stock 09/30/99 P 42,450 A $8.125 I By Main Street
Merchant
Partners II, L.P.
- ------------------------------------------------------------------------------------------------------------------------------------
Common Stock 12/31/99 P 33,334 A $6.00 I By Main Street
Merchant
Partners II, L.P.
- ------------------------------------------------------------------------------------------------------------------------------------
Common Stock 105,784 I By Main Street
Merchant
Partners II, L.P.
- ------------------------------------------------------------------------------------------------------------------------------------
Common Stock 300 I Custodian Under
TX UGMA
- ------------------------------------------------------------------------------------------------------------------------------------
Common Stock 10,000 I By General
Partnership
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
</TABLE>
Reminder: Report on a separate line for each class of securities beneficially
owned directly or indirectly.
* If this form is filed by more than one reporting person, see Instruction
4(b)(v).
<PAGE>
FORM 4 (continued)
TABLE II--DERIVATIVE SECURITIES ACQUIRED, DISPOSED OF, OR BENEFICIALLY OWNED
(e.g., puts, calls, warrants, options, convertible securities)
<TABLE>
<CAPTION>
- -----------------------------------------------------------------------------------------------------------------------------
1. Title of Derivative 2. Conver- 3. Trans- 4. Transac- 5. Number of Deriv-
Security (Instr. 3) sion or action tion Code ative Securities
Exercise Date (Instr. 8) Acquired (A) or
Price of (Month/ Disposed of (D)
Deriv- Day/ (Instr. 3, 4, and 5)
ative Year)
Security
---------------------------------------------------
Code V (A) (D)
- -----------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C>
- -----------------------------------------------------------------------------------------------------------------------------
- -----------------------------------------------------------------------------------------------------------------------------
- -----------------------------------------------------------------------------------------------------------------------------
- -----------------------------------------------------------------------------------------------------------------------------
- -----------------------------------------------------------------------------------------------------------------------------
- -----------------------------------------------------------------------------------------------------------------------------
- -----------------------------------------------------------------------------------------------------------------------------
- -----------------------------------------------------------------------------------------------------------------------------
- -----------------------------------------------------------------------------------------------------------------------------
- -----------------------------------------------------------------------------------------------------------------------------
</TABLE>
TABLE II--DERIVATIVE SECURITIES ACQUIRED, DISPOSED OF, OR BENEFICIALLY OWNED
(e.g., puts, calls, warrants, options, convertible securities)--CONTINUED
<TABLE>
<CAPTION>
- ------------------------------------------------------------------------------------------------------------------------------------
6. Date Exer- 7. Title and Amount of 8. Price 9. Number 10. Owner- 11. Na-
cisable and Underlying Securities of of Deriv- ship ture
Expiration (Instr. 3 and 4) Deriv- ative Form of In-
Date ative Secur- of De- direct
(Month/Day/ Secur- ities rivative Bene-
Year) ity Bene- Secu- ficial
(Instr. ficially rity: Owner-
-------------------------------------------- 5) Owned Direct ship
Date Expira- Amount or at End (D) or (Instr.
Exer- tion Title Number of of Indi- 4)
cisable Date Shares Month rect (1)
(Instr. 4) (Instr. 4)
- ------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C>
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------------------------------------------
</TABLE>
Explanation of Responses:
**Intentional misstatements or omissions of facts constitute Federal Criminal
Violations.
See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed.
If space provided is insufficient, see Instruction 6 for procedure.
Potential persons who are to respond to the collection of information contained
in this form are not required to respond unless the form displays a currently
valid OMB Number.
/s/ VINCENT D. FOSTER January 7, 2000
------------------------------- -----------------
**Signature of Reporting Person Date
