Under the Securities Exchange Act of 1934

(Name of Issuer)

(Title of Class of Securities)

(CUSIP Number)

(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)

Copy to:

Michael H. Hyer, Esq.

300 East John Carpenter Freeway, Suite 1645

Irving, Texas 75062

972-653-6141

(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. o

2

3

4

5

6

7

8

The class of equity securities to which this Schedule 13D relates is common stock, $.001 par value (the “Shares”) of U.S. Concrete, Inc. (the “Issuer”), whose principal executive offices are located at 2925 Briarpark, Suite 1050, Houston, Texas 77042. 

This Schedule 13D is filed jointly by (a) HBMA Holdings, Inc., a Delaware corporation (“HBMA”), and (b) (i) Dr. Adolf Merckle, a citizen of the Federal Republic of Germany, (ii) Ms. Ruth Merckle, a citizen of the Federal Republic of Germany, (iii) Mr. Ludwig Merckle, a citizen of the Federal Republic of Germany, (iv) Mr. Tobias Merckle, a citizen of the Federal Republic of Germany, (v) Dr. Philipp Merckle, a citizen of the Federal Republic of Germany, (vi) Ms. Jutta Breu (nee Jutta Merckle), a citizen of the Federal Republic of Germany (collectively, the “Merckle Family”) (HBMA and the Merckle Family collectively, the “Reporting Persons”).

HBMA is a subsidiary in a multi-tier corporate organization ultimately controlled by the Merckle Family.  Annex A attached hereto sets forth the name, state or other place of organization, principal business and address of its principal place of business and principal office of the HeidelbergCement corporate entities between the Merckle Family and HBMA.  HBMA is a Delaware corporation whose principal business is the ownership of subsidiary companies whose core products are cement, ready-mixed concrete, aggregates, concrete and steel pipe, brick and related products.  The address of HBMA’s principal offices and place of business is 300 East John Carpenter Freeway, Suite 1645, Irving, Texas 75062.  The name, position with HBMA, present principal occupation or employment and business address of each of the board members and executive officers of HBMA are set forth in Annex B attached hereto.

Dr. Adolf Merckle and Ms. Ruth Merckle are husband and wife.  Mr. Ludwig Merckle, Mr. Tobias Merckle, Dr. Philipp Merckle and Ms. Jutta Breu (nee Jutta Merckle) are the children of Dr. Adolf Merckle and Ms. Ruth Merckle.   The name, citizenship, business addresses and principal occupation of each member of the Merckle Family are set forth in Annex C attached hereto.

The Merckle Family owns, directly or indirectly through investment vehicles, all the outstanding shares of Spohn Cement GmbH, a corporation incorporated under the laws of the Federal Republic of Germany (“Spohn”).  The address of Spohn’s principal offices is Diekstraat 3, 25870 Norderfriedrichskoog, Germany.  Spohn is a holding company which holds approximately 53.6% of the outstanding shares of HeidelbergCement AG, a corporation incorporated under the laws of the Federal Republic of Germany (“HeidelbergCement”).  In addition, other investment vehicles owned directly or indirectly by Dr. Adolf Merckle own an additional 25.46% of the outstanding shares of HeidelbergCement.  HeidelbergCement is a corporation whose core products are cement, ready-mixed concrete, aggregates and related products. The address of HeidelbergCement’s principal office is Berliner Strasse 6, 69120 Heidelberg, Germany.  Dr. Adolf Merckle, Mr. Ludwig Merckle and Mr. Tobias Merckle are members of the supervisory board of HeidelbergCement.

HBMA is an indirect 100% owned subsidiary of HeidelbergCement.

During the last five years, none of the Reporting Persons or, to the knowledge of the Reporting Persons, none of the entities set forth in Annex A and none of the persons set forth in Annex B has been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors) or has been a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, US federal or state securities laws or finding any violation with respect to such laws.

Pursuant to Rule 13D-1(k) under the Securities Exchange Act of 1934 (the “Exchange Act”), the Reporting Persons have agreed to file one statement with respect to their beneficial ownership of Shares of the Issuer and the joint Schedule 13D of the Reporting Persons as amended from time to time is herein referred to as “this Schedule 13D.”

9

HBMA made its purchases of Shares based on the Reporting Persons’ belief that the Issuer’s Shares at current market prices are undervalued and represent an attractive investment opportunity.  At present the Reporting Persons have no plans other than to hold the Shares for investment purposes.

The Reporting Persons do not have any current plans or proposals that relate to or would result in any of the actions set forth in items (a) through (j) of Item 4 of the instructions to Schedule 13D, although the Reporting Persons reserve the right to develop such plans or proposals.

Depending upon overall market conditions, other investment opportunities available to the Reporting Persons, and the availability of Shares at prices that would make the purchase of additional Shares desirable, the Reporting Persons may endeavor to increase their position in the Issuer through, among other things, the purchase of Shares or options on such Shares on the open market, in private transactions, through a tender offer or otherwise, on such terms and at such times as the Reporting Persons may deem advisable. Subject to a number of factors, the Reporting Persons may also decide in the future to propose one or more representatives for election to the board of directors of the Issuer or to propose other matters for consideration and approval by the Issuer’s stockholders or board of directors.  Such other matters may include transactions involving a sale of assets of the Issuer or a merger involving the Issuer in which HBMA or an affiliate may be a participant and which may involve a change of control of the Issuer.

(a)           The responses of the Reporting Persons to Rows (7) through (11) and (13) of the cover pages to this Schedule 13D are hereby incorporated by reference. The percentages set forth in this Item 5 are calculated based upon the number of Shares (excluding those held in treasury) outstanding of 39,745,828 as of May 6, 2008 as set forth in the Issuer’s Quarterly Report on Form 10-Q for the quarter ended March 31, 2008.

HBMA owns 3,233,451 Shares (the “HBMA Shares”) representing 8.1% of the outstanding Shares of the Issuer.  Neither the Merckle Family nor any of the entities listed on Annex A other than HBMA directly own any Shares or other equity securities of the Issuer.

Since HBMA is an indirect wholly-owned subsidiary of HeidelbergCement, HeidelbergCement may be deemed to beneficially own the HBMA Shares.  All the entities described on Annex A as middle-tier subsidiaries of HeidelbergCement are parent entities of HBMA, all of which may be deemed to beneficially own the HBMA Shares.

Spohn owns approximately 53.6% of the outstanding shares of HeidelbergCement.  Spohn is directly or indirectly through investment vehicles wholly owned by the Merckle Family.  In addition, other investment vehicles owned by Dr. Adolf Merckle own an additional 25.46% of the outstanding shares of HeidelbergCement.  Therefore, the members of the Merckle Family may be deemed to be the beneficial owners of the HBMA Shares by virtue of their ownership of Spohn and HeidelbergCement.  Spohn may be deemed to beneficially own the HBMA Shares by virtue of  its ownership in HeidelbergCement.

(b)           Each Reporting Person may be deemed to share the power to vote or direct the vote and to dispose or to direct the disposition of the HBMA Shares which may be deemed to be beneficially owned by such Reporting Person as indicated in rows (7) through (11) and (13) of the cover pages to this Schedule 13D.

10

Spohn may be deemed to share with HeidelbergCement, all middle-tier subsidiaries between HeidelbergCement and HBMA, and HBMA the power to vote or direct the vote and to dispose or direct the disposition of the HBMA Shares.

Members of the Merckle Family may be deemed to share with Spohn, HeidelbergCement, all middle-tier subsidiaries between HeidelbergCement and HBMA, and HBMA the power to vote or direct the vote and to dispose or direct the disposition of the HBMA Shares.  Each member of the Merckle Family may be deemed to share with the other members of the Merckle Family the power to vote or direct the vote and to dispose or direct the disposition of the HBMA Shares.

(c)           Information on transactions in the Shares effected by the Reporting Persons during the sixty day period prior to the date of this Schedule 13D is set forth in Annex D.  All transactions were purchases by HBMA effected in the open market.

(d)           Except as described in this Schedule 13D, no other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the HBMA Shares owned by the Reporting Persons.

(e)           Not applicable.

11

ANNEX A

Corporate Entities

HeidelbergCement AG Middle-Tier Subsidiaries

12

13

ANNEX B

Board of Directors and Executive Officers of HBMA Holdings, Inc.

The name, present positions with HBMA, present principal occupation or employment and business address of each of the board members and executive officers of HBMA Holdings, Inc. are set forth below.  All persons named in the table below are citizens of the United States.

¹Lehigh Hanson, Inc. is a downstream subsidiary of HBMA Holdings, Inc.

14

ANNEX C

Members of the Merckle Family

The name, present principal occupation or employment and business address of each of the members of the Merckle Family are set forth below.  All persons named in the table below are citizens of the Federal Republic of Germany.

15

ANNEX D

HBMA Shares

¹All purchases were made on the open market.

16

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, the undersigned certifies that the information set forth in this statement is true, complete and correct.

17